AeroElectric-Archive.digest.vol-lz
October 15, 2013 - October 26, 2013
how it works in any airplane.
ECU (back up): It contains a duplicate motherboard accessed via a
toggle switch on the control panel...no change in electrical load.
2. One serviceable fuel pump w/ an unclogged filter. Fuel pump draws 5.7
amps.
Fuel pump (back up): I have a second pump (same rating as first) w/
separate filter.
I BELIEVE that's all I need to keep the engine running...total load: 22.2
amps. (Round it up to say 25 amps?...what have I missed?)
REAL numbers that I believe will prove to be
much smaller. 250 Watts demand by an engine
that's fitted with only 550 Watts of alternator
seems out of whack. Are these engines flying
now? What's the change that the supplier of
this engine could be persuaded to get some
real numbers off of a customer's airplane . . .
or perhaps his own?
If this electrical load for the engine is routed thru a (always hot?)
battery bus,
would we then want to tally up additional loads on an endurance bus as a
back up to everything deemed essential which would be normally drawing from
the EXP Bus in the event that the EXP fizzles?
You're talking dual failure in the span of time
needed to use all fuel aboard. The only reason
you need to run the engine battery-only is if
the alternator quits. If this were a Part 23
aircraft, we don't consider dual failures as
part of the cert process. If the guys behind
the desks don't worry about it . . . well . . .
they're paid to worry. We get to do our own
FMEA based mitigation of risk.
And how do we provide the juice if the alternator fizzles as well?
Note: regarding batteries: the Odyssey PC680 capacity is 16 ah, providing 24
"reserve minutes @ 25 amps"...see:
http://www.odysseybatteries.com/mainpages/batteries.htm
Assuming dual batteries and both battery states of 75%, I figure 24 ah
available which would give 36 "reserve minutes" @ 25 amp draw.
Does that sound right to you?...or am I getting way ahead of myself?
Just a little . . . and if the numbers you've
been offered are real, then alternator failure
on your airplane would be an emergency situation.
30 minutes of battery-only endurance comes with
severe pucker-factor. Are you really sure you want
to fly this engine under that kind of risk?
A rhetorical question at this stage of the
design . . . I can't imagine an automotive manufacturer
willing to toss off that kind of energy budget just
to keep the engine running. I'll bet that engine
in a car would run for hours on a good battery
if all other loads were eliminated.
Let's talk with your engine guy.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
>I missed the original post, so I might not have all info needed for
>a reply, but here goes: not having a diode across a relay's coil (as
>purchased) is more the norm than the exception. Diodes for the job
>described are dirt cheap (pennies, last time I checked) & available
>anywhere you can buy electronic components. If the contactor does
>what you need it to do, just add the diode.
Don't 'replace' . . . modify. Diodes are cheap,
readily available and non-critical as to electrical
ratings. My personal favorites are the 1N540X SERIES
devices where X can be any digit.
Radio Shack will sell you two of these in a blister
pak of two for about $2. See:
http://tinyurl.com/n6wq2bx
Everyone who claims to be in the electronics parts
business will have them at similar or cheaper prices.
These are all electrically VERY robust . . . smaller
devices would suffice electrically. But they are
mechanically robust too. Easier to work with and
less subject to installer-damage.
Here's a couple of articles on the topic . . .
http://tinyurl.com/nva2xdy
http://tinyurl.com/25wjo7w
There's a lot of ol' mechanic's tales and hangar
mythology about system spikes loose in the wild.
If anyone encounters a convincing tale that
give you the urge to spend more money or to rip
out part of an existing system, let's talk about
it here first.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 03:52 PM 10/15/2013, you wrote:
>On Oct 15, 2013, at 9:22 AM, Robert L. Nuckolls, III wrote:
>
>> > How many pumps?
>>
>> My engine is designed to run on one pump;
>> I have a back up pump as well; each pump has it's own filter; the
>> back up is intended to handle failure or clogging of the first
>> pump. The hi pressure pumps draw 5.7 amps each. Both pumps should
>> be able to be energized by either battery...and...it seems to me
>> that I should want to toggle switch from one pump to the other.
>>
>> Why all this layered 'redundancy'. Under what conceivable
>> condition can you imagine that you'll be siting in the
>> cockpit with a stumbling engine flipping switches to see
>> what combination of positions gets the engine back?
>
>Bob...to answer your question, a clogged fuel filter is eminently
>conceivable to me...to
>provide a back up pump with separate filter seems fundemental...to
>be able to switch from one pump to another seems straightforward enough.
Okay, each pump has one switch closing a feed
thru a fuse from one battery. Since you have two batteries,
then standby pump from the main battery through
one fuse and a switch, main pump from the engine battery
through one fuse and a switch. Noting is gained
by making offering dual power sources to each pump.
>I'm simply mystified as to why you imply that "this layered
>'redundancy' " would create rather than solve problems or confusion
>if the engine starts sputtering.
The more switches and switch positions multiplies
possible combinations of operating conditions . . .
EACH presenting a new endurance mode calculation.
If your 20+ amps endurance numbers are real, then
alternator failure is a TENSE condition no matter
how many options there are. Likelihood of making
a poor decision goes up with the square of tension.
Liklihood of having a pump failure on top of an
alternator failure is exceedingly remote and not
generally considered in a Part 23 airplane. So this
says a simple, totally independent substitute for a
main pump that has failed for any reason is
sufficient.
Let's see what the real energy budget is and see
what it takes to offer at least an hour of flight
on batteries nearing end of service life.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | New electrical architecture with ENGINE BUS |
At 11:19 PM 10/14/2013, you wrote:
>
> > Attached is an electrical drawing with an ENGINE BUS.
>
>Joe, I know this has been addressed on the list before, but can you remind
>me what software you use to produce such drawings?
>\
TurboCAD will open, edit, save and print the
AutoCAD drawings on my website. It will also
import DXF files from other CAD platforms.
The price is right too . ..
http://tinyurl.com/kuj6vqx
Another bargain is NanoCAD from this
site.
http://tinyurl.com/9yl3ug5
This is a freeware look-alike for AutoCAD.
I don't have it installed on this machine
but I did try it out about two years ago.
Not a 100.0% clone for behavior but very
close. The vast majority of "things" that
are part of my AutoCAD habits embedded
after 20 years played seamlessly on
NanoCAD. The few hiccups were easily
managed . . . it's a very intuitive
program.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Copper Foil width for VOR antenna |
At 04:26 PM 10/15/2013, you wrote:
>
>Thx... I am actually thinking of using the braid only as the antenna
>material... as part of making a proper balun one would only use the
>braid to connect to the antenna elements anyway while the center
>cnnductor is not connected... this should avoid the problem you are
>describing... as long as i can successfully slide about a 16" long
>undisturbed braid-external shielding up on the stripped coax to
>avoid the large resulting gap.
>
>Water will not get into this setup as it will be saturated with epoxy.
The problem with embedded antennas is the potential for
fatigue failure of the conductors if the composite
structure flexes. This can produce hairline fractures
in foil or wire antennas bonded to a composite surface. It can
make your antenna conductors look like the wires in a strain
guage . . . that stretch and compress as the surface responds
to structure flexing.
RF bandwidth of the wider foil is attractive but as mentioned
here, insignificant with respect to performance. Consider an
ALL COAX antenna assembly. Balun is optional . . . cool
but performance difference is very small. Making the
antenna elements from coax braid FLOATING INSIDE a piece of 1/4"
Nylon tubing will get you a simple antenna material,
adequate performance and the tubing isolates the antenna
from structure so that flexing doesn't mechanically irritate
the elements.
Bob . . .
________________________________________________________________________________
| From: | "Fisher Paul A." <FisherPaulA(at)johndeere.com> |
| Subject: | Re: Copper Foil width for VOR antenna |
Just another data point. I used Mr. Weir's antennas in my Q-200 (fully composite
structure). The vertically polarized comm antenna in the tail and the horizontally
polarized VOR antenna in the main wing. Both were installed exactly
as Mr. Weir describes using his kit including the copper foil. Both antennas have
given satisfactory performance for 23+ years and ~1,500 flight hours.
Paul A. Fisher
Q-200 N17PF
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III
Sent: Tuesday, October 15, 2013 10:10 PM
Subject: Re: AeroElectric-List: Re: Copper Foil width for VOR antenna
-->
At 04:26 PM 10/15/2013, you wrote:
>
>Thx... I am actually thinking of using the braid only as the antenna
>material... as part of making a proper balun one would only use the
>braid to connect to the antenna elements anyway while the center
>cnnductor is not connected... this should avoid the problem you are
>describing... as long as i can successfully slide about a 16" long
>undisturbed braid-external shielding up on the stripped coax to avoid
>the large resulting gap.
>
>Water will not get into this setup as it will be saturated with epoxy.
The problem with embedded antennas is the potential for
fatigue failure of the conductors if the composite
structure flexes. This can produce hairline fractures
in foil or wire antennas bonded to a composite surface. It can
make your antenna conductors look like the wires in a strain
guage . . . that stretch and compress as the surface responds
to structure flexing.
RF bandwidth of the wider foil is attractive but as mentioned
here, insignificant with respect to performance. Consider an
ALL COAX antenna assembly. Balun is optional . . . cool
but performance difference is very small. Making the
antenna elements from coax braid FLOATING INSIDE a piece of 1/4"
Nylon tubing will get you a simple antenna material,
adequate performance and the tubing isolates the antenna
from structure so that flexing doesn't mechanically irritate
the elements.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | EXP 2 Bus workaround |
At 09:51 PM 10/15/2013, you wrote:
>Bob,
>A friend of mine is running a Mazda engine on a test stand and is
>using a lot of the same controller, injectors, coils, etc that Fred
>is using. I asked him for some amperage load information and this
>is what he measured on his running engine:
>
>"I went out and measured the current requirements of the various
>systems on my Renesis test stand which has an EC2 and GM D585
>ignition coils. System voltage was 15V with a battery charger
>attached and the CAS was driven to be equivalent to an engine RPM of
>5000. When the EC2 is powered up, there are also a tach, 2 VDO
>temperature gauges, an O2 gauge, a voltmeter, and an electronic fuel
>pressure gauge powered as well.
>
>The results for the individual systems are:
>EC2 and gauges: 0.8 A
>2 leading coils: 2.4 A
>2 trailing coils: 2.4 A
>2 primary injectors 0.7 A
>2 secondary injectors: 0.7 A
>1 Mazda stock RX7 fuel pump: 3.8 A
>
>Total in normal running config: 10.8 A
>
>The fuel pumps that RWS sold draw very close to the same current
>that the Mazda one does."
>
>This hopefully will shed some light on the load that Fred will be
>experiencing on his engine
Aha! Numbers! Thank you for taking the
time to go measure. Are these numbers
RPM dependent? Another constellation of values
at 4000 would be very interesting.
I am reminded of a remark by Lord Kelvin who said . . .
"In physical science a first essential step in the direction
of learning any subject is to find principles of numerical
reckoning and practicable methods for measuring some quality
connected with it. I often say that when you can measure what
you are speaking about, and express it in numbers, you know
something about it; but when you cannot measure it, when you
cannot express it in numbers, your knowledge is of a meagre
and unsatisfactory kind; it may be the beginning of knowledge,
but you have scarcely in your thoughts advanced to the stage
of science, whatever the matter may be."
Okay, how would numbers like this (remember, these
are exemplar, i.e. similar numbers) drive the thought
processes for architecture for Fred's airplane with
an EXP=Bus installed? The real numbers for Fred's
engine may not be available until he can run the engine.
Bill's numbers do give reason to believe that Fred's
Plan-B design goals may not be so limited as originally
thought.
With two, PC-680 batteries on board, Fred's airplane
carries 32 a.h. of capacity at a 20 hr rate when new.
Consulting the discharge curves for a PC680 we see . . .
Emacs!
Assuming Fred's real engine demands are on the order of 10A,
then a new PC680 will sustain flight for about 1.2 hrs. Running
BOTH batteries in parallel would load each battery to the tune
of 5A for an endurance of 2.7 hours. Hmmmm . . . this gives
us numbers for consideration that might lead to a design that
eliminates the word "emergency" from the description of an
alternator failure event.
This line of reasoning becomes more focused when we
get real numbers from the folks who manufactured Fred's
engine but the process is moving in the right direction.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Relay for Critical Power Feed |
| From: | Thomas E Blejwas <tomblejwas(at)yahoo.com> |
Thanks Eric. I was also missing the inherent redundancy in the bridge diode.
If the diode through which current is flowing fails, switching to the other power
source (if it isn't already on) restores current. The two buses might be
connected, but that would not prevent power to the critical component.
I will save the relay arrangement I described for switching between my fuel pumps.
If both are inadvertently energized, the pressure will exceed the capabilities
of my fuel regulator. The relay arrangement will prevent that.
Tom
Sent from my iPad
________________________________________________________________________________
| Subject: | Re: Relay for Critical Power Feed |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
I claim this is a better way to go and have sold lots of these to Aeroelectric
builders doing Z-19
http://www.periheliondesign.com/powerschottkydiodes.htm
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410702#410702
________________________________________________________________________________
| Subject: | Re: New electrical architecture with ENGINE BUS |
| From: | Sacha <uuccio(at)gmail.com> |
>> can you remind
>> me what software you use to produce such drawings?
>
> TurboCAD
> NanoCAD
> DraftSight
Joe/Jan/Bob
Thank you. I've downloaded nanoCAD and will give it a try.
I'm planning on using it to produce a diagram of the wiring on my Kitfox (which
did not originate from a very carefully thought out plan) and then presenting
it to the list to for advice on modifying it.
Sacha
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 16, 2013, at 9:25 AM, Robert L. Nuckolls, III wrote:
> This line of reasoning becomes more focused when we
> get real numbers from the folks who manufactured Fred's
> engine but the process is moving in the right direction.
Bob...I cannot get any additional data from my engine guy w/ regard to
the electrical power draw at cruise rpm (or for any other rpm for that
matter) unless something can be gleaned from a video of the dyno
readout:
http://www.youtube.com/watch?v=epgQaA4SXe8
...frankly, I can't read a thing from the out of focus monitor...
Fred
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 02:48 PM 10/16/2013, you wrote:
>On Oct 16, 2013, at 9:25 AM, Robert L. Nuckolls, III wrote:
>
>> This line of reasoning becomes more focused when we
>> get real numbers from the folks who manufactured Fred's
>> engine but the process is moving in the right direction.
>
>Bob...I cannot get any additional data from my engine guy w/ regard
>to the electrical power draw at cruise rpm (or for any other rpm for
>that matter) unless something can be gleaned from a video of the dyno readout:
>
><http://www.youtube.com/watch?v=epgQaA4SXe8>http://www.youtube.com/watch?v=epgQaA4SXe8
>
>...frankly, I can't read a thing from the out of focus monitor...
>
>Fred
Which engine are we talking about? Is there
no supplier support? Is there a user's forum
of individuals who are already flying?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: New electrical architecture with ENGINE BUS |
At 01:48 PM 10/16/2013, you wrote:
>
> >> can you remind
> >> me what software you use to produce such drawings?
> >
> > TurboCAD
> > NanoCAD
> > DraftSight
>
>Joe/Jan/Bob
>
>Thank you. I've downloaded nanoCAD and will give it a try.
>I'm planning on using it to produce a diagram of the wiring on my
>Kitfox (which did not originate from a very carefully thought out
>plan) and then presenting it to the list to for advice on modifying it.
>Sacha
All of the z-figures are available in both
pdf and dwg formats. NanoCAD will open, edit,
print and save the .dwg drawings. So you can
start with a almost-but-not-quite drawing
and modify to meed your needs.
Have you used a cad program of any kind
before?
Bob . . .
________________________________________________________________________________
| Subject: | Re: Copper Foil width for VOR antenna |
| From: | "p32gxy" <p32gxy(at)gmail.com> |
I am loving the idea of a protective sheath/tube to achieve mechanical isolation...
Unfortunately, i don't see how I can make use of this approach without either drilling
holes in the spar or messing up the wing's shape/airflow
The VOR antenna I can install has to be flat so that it integrates into the wing
surface. Don't want to be compromising the wing skin... moving the antenna is
also not an option because the only place I can keep the tips away from "metal"
antennae like structures is in the outboard 1/3 of the wing.
I am all open to suggestions and will consider anything and everything including
novel designs and unusual shapes as I am finding that the 22.8" per leg of the
V shaped antennae is hard to place without interference.... please keep them
comming.
Thx.
nuckolls.bob(at)aeroelect wrote:
> At 04:26 PM 10/15/2013, you wrote
> The problem with embedded antennas is the potential for
> fatigue failure of the conductors if the composite
> structure flexes. This can produce hairline fractures
> in foil or wire antennas bonded to a composite surface. It can
> make your antenna conductors look like the wires in a strain
> guage . . . that stretch and compress as the surface responds
> to structure flexing.
>
> RF bandwidth of the wider foil is attractive but as mentioned
> here, insignificant with respect to performance. Consider an
> ALL COAX antenna assembly. Balun is optional . . . cool
> but performance difference is very small. Making the
> antenna elements from coax braid FLOATING INSIDE a piece of 1/4"
> Nylon tubing will get you a simple antenna material,
> adequate performance and the tubing isolates the antenna
> from structure so that flexing doesn't mechanically irritate
> the elements.
>
>
> Bob . . .
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410717#410717
________________________________________________________________________________
| Subject: | Re: New electrical architecture with ENGINE BUS |
| From: | "user9253" <fransew(at)gmail.com> |
I used one of those free CAD programs for awhile. When I went to view one of my
drawings at a later date, I could not open it because the program license had
expired after one year. It was necessary to register again to get another free
license to use the program for one more year. What if I did not happen to
have an internet connection? Or what if the company goes out of business? Then
I would not be able to open my drawings. So I acquired TurboCAD. I can open
my drawings whenever I want without depending on the internet or the software
manufacturer.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410719#410719
________________________________________________________________________________
| From: | rayj <raymondj(at)frontiernet.net> |
| Subject: | Re: Copper Foil width for VOR antenna |
A technique used by some boat builders to form pillow blocks for prop
shafts is to coat the shaft with wax of sufficient thickness to assure
clearance between the block and the shaft when the wax is removed.
WARNING, I HAVE NOT TRIED THE TECHNIQUE DISCUSSED BELOW. IT IS ONLY
SPECULATION!!!!!
A similar approach might be applied to the copper strip in the matrix.
Coat it with several layers of wax or mold release before imbeding it in
the matrix. The theory is that the wax will prevent the matrix from
bonding to the copper, effectively creating a space on either side of
the copper allowing it to move slightly to avoid being stressed when the
matrix is deformed. The downside is that it is functionally a
delamination. Whether or not that is acceptable would have to be
decided by the builder.
Raymond Julian
Kettle River, MN.
"And you know that I could have me a million more friends,
and all I'd have to lose is my point of view." - John Prine
On 10/16/2013 06:27 PM, p32gxy wrote:
>
> I am loving the idea of a protective sheath/tube to achieve mechanical isolation...
> Unfortunately, i don't see how I can make use of this approach without either
drilling holes in the spar or messing up the wing's shape/airflow
>
> The VOR antenna I can install has to be flat so that it integrates into the wing
surface. Don't want to be compromising the wing skin... moving the antenna
is also not an option because the only place I can keep the tips away from "metal"
antennae like structures is in the outboard 1/3 of the wing.
>
> I am all open to suggestions and will consider anything and everything including
novel designs and unusual shapes as I am finding that the 22.8" per leg of
the V shaped antennae is hard to place without interference.... please keep them
comming.
>
> Thx.
>
>
> nuckolls.bob(at)aeroelect wrote:
>> At 04:26 PM 10/15/2013, you wrote
>> The problem with embedded antennas is the potential for
>> fatigue failure of the conductors if the composite
>> structure flexes. This can produce hairline fractures
>> in foil or wire antennas bonded to a composite surface. It can
>> make your antenna conductors look like the wires in a strain
>> guage . . . that stretch and compress as the surface responds
>> to structure flexing.
>>
>> RF bandwidth of the wider foil is attractive but as mentioned
>> here, insignificant with respect to performance. Consider an
>> ALL COAX antenna assembly. Balun is optional . . . cool
>> but performance difference is very small. Making the
>> antenna elements from coax braid FLOATING INSIDE a piece of 1/4"
>> Nylon tubing will get you a simple antenna material,
>> adequate performance and the tubing isolates the antenna
>> from structure so that flexing doesn't mechanically irritate
>> the elements.
>>
>>
>> Bob . . .
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=410717#410717
>
>
________________________________________________________________________________
| Subject: | Re: Copper Foil width for VOR antenna |
| From: | "p32gxy" <p32gxy(at)gmail.com> |
raymondj(at)frontiernet.n wrote:
> A technique used by some boat builders to form pillow blocks for prop
shafts is to coat the shaft with wax of sufficient thickness to assure
clearance between the block and the shaft when the wax is removed..
>
Well... I have been thinking of something similar... except using copper foils such as http://www.mcmaster.com/#9053k12/=oyvy3i and putting it between 2 layers of PTFE tape such as http://www.mcmaster.com/#76475a43/=oyw325 before covering the thing with 1 ply of 3oz glass.
This approach, I think, would create a non-stick copper foil 'assembly' to which
epoxy would not stick... effectively the copper tape would not be bound to the
wing skin. The push-pull on the copper foil should be much reduced...
The "de-lamination" should not be an issue as the covering fiberglass layer only
has the purpose of keeping the tape in place... no structural impact as i understand
it.
The only place to be fixed would be where the coax attaches as the leads would
have to penetrate the wing skin through very small holes.
I don't mind spending a bit more money upfront rather than fixing broken VOR antennae
later :-)
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410726#410726
________________________________________________________________________________
| From: | rayj <raymondj(at)frontiernet.net> |
| Subject: | Re: Copper Foil width for VOR antenna |
The only potential problem I see with that is that the epoxy might be
drawn in between the 2 pieces of plastic by capillary action or if it's
vacuum bagged, and then bond to the copper. You might be able to get
some thin wall HDPE tubing that will pull down flat if you vacuum bag
it. I wonder if you could just put some grease on it. I suppose a
couple of test layups will answer most of the questions.
I just had another thought. Could you lay a thin piece of styrofoam in
and then dissolve it and slide the foil in? Then just fill the slot,
leaving the copper anchored at one end.
Good luck, I look forward to hearing what your solution is.
Raymond Julian
Kettle River, MN.
"And you know that I could have me a million more friends,
and all I'd have to lose is my point of view." - John Prine
On 10/16/2013 10:15 PM, p32gxy wrote:
>
>
> raymondj(at)frontiernet.n wrote:
>> A technique used by some boat builders to form pillow blocks for prop
shafts is to coat the shaft with wax of sufficient thickness to assure
clearance between the block and the shaft when the wax is removed..
>>
>
>
> Well... I have been thinking of something similar... except using copper foils such as http://www.mcmaster.com/#9053k12/=oyvy3i and putting it between 2 layers of PTFE tape such as http://www.mcmaster.com/#76475a43/=oyw325 before covering the thing with 1 ply of 3oz glass.
>
> This approach, I think, would create a non-stick copper foil 'assembly' to which
epoxy would not stick... effectively the copper tape would not be bound to
the wing skin. The push-pull on the copper foil should be much reduced...
>
> The "de-lamination" should not be an issue as the covering fiberglass layer only
has the purpose of keeping the tape in place... no structural impact as i
understand it.
>
> The only place to be fixed would be where the coax attaches as the leads would
have to penetrate the wing skin through very small holes.
>
> I don't mind spending a bit more money upfront rather than fixing broken VOR
antennae later :-)
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=410726#410726
>
>
________________________________________________________________________________
| Subject: | Re: New electrical architecture with ENGINE BUS |
| From: | Sacha <uuccio(at)gmail.com> |
>> NanoCAD will open, edit, print and save the .dwg drawings. So you can sta
rt with a almost-but-not-quite drawing and modify to meed your needs.
Thanks, I'll do that. I have to first figure out what my setup actually is. T
he wiring was mostly five by a friend of mine who's been flying for 30+ year
s and who built a few planes before, including one of his own designs.
We discussed certain things like OV protection and the ability to turn the A
lternator off (which he considered unnecessary on a Rotax 912 while using it
s inbuilt generator, but which I insisted on) but I didn't make a note of al
l the schematics at the time. I'll have to sit down and write it all out.
>> Have you used a cad program of any kind before?
No. I tried poking around last night and was able to open the Dwg files on t
he aero electric site. It took me a while to figure out how to simply copy a
nd paste items and then I had to scale them to make them fit what I had draw
n... Seems like i might save done time with some decent training material. A
re you aware of any?
I'm considering buying TurboCAD but most of the stuff on ebay US doesn't shi
p to Italy so it would be a bit convoluted to do so. It's so difficult to ge
t hands on stuff here compared to the US where you can just order and get it
overnight!
>
________________________________________________________________________________
| From: | "The Kuffels" <kuffel(at)cyberport.net> |
| Subject: | Re: Copper Foil width for VOR antenna |
<< don't see how I can make use of this approach without either drilling
holes in the spar or messing up the wing's shape/airflow >>
We have reached the point where we need more information. Are you talking
Rutan moldless composite construction or premolded skins a la
Lancair/Glasair?
In the case of the former and you have not laminated the wing skins yet,
there is no problem. Do what you would have to do with the coax anyway, cut
a groove in the foam for the tubes with the braids inside. Make the
grooves deeper than needed and cover with microbaloon slurry and a temporary
layer of peelply. This forms a surface for glassing with no delamination
areas or profile distortion.
With premolded wing panels you glue the tubes to the undersurface. With
braid as my antenna elements, I would have no qualms about just ShoGooing
them to the panel undersurface. The ShoGoo remains flexible enough to not
stress the wires. For routing the feedline, structural theory says there is
little problem drilling a small hole in the middle of the vertical shear
web, particularly outboard. But don't get too compulsive about routing the
end of the coax/balun directly away from the Vee. Even bent 90 degrees to
the Vee you won't see much, if any, difference.
<< 22.8" per leg of the V shaped antennae is hard to place without
interference >>
The purpose of making the legs Vee shaped is to remove the null reception
points off the ends of a straight dipole. But you don't need 45 degree
bends to do this. A much shallower angle will still give adequate
performance. And there is no problem with curlling the tips somewhat near
the leading edge.
Understand we don't need the last db of signal strength in this application.
In a composite fuselage a 23" length of wire dangling from the center
conductor on the back of the radio would still give "adequate performance".
Tom Kuffel
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | To CAD or not to CAD . . . that is the question |
I tried poking around last night and was able to open the Dwg files
on the aero electric site. It took me a while to figure out how to
simply copy and paste items and then I had to scale them to make them
fit what I had drawn... Seems like i might save done time with some
decent training material. Are you aware of any?
That, my friend, is the $64K question.
We've had these discussions about the use
of CAD for doing wiring diagrams many times
over the years here on the List. I've always
encouraged individuals to acquire and become
reasonably conversant in some kind of CAD
program . . . but that advice is 'colored'
by my own utilization of AutoCAD which dates
back to 1988 or so running AutoCAD v2.17 on
a 4MHz PC-XT with 64K of ram, 20M HD, 9"
amber screen and a dot-matrix printer.
My comfort level with AutoCAD for the tasks
I do is very high. At the same time
I can tell you that I use less than 5% of its
capabilities. AutoCAD and clones understand
hundreds of commands . . . I can give you a list
of commands . . . about 50 . . . that suffice
for 99% of my drawing needs for the past 25
years. So yeah, I have a "training manual"
that is a subset list of the total command set.
Backing off a bit, let's consider the complexity
of your drawing task. Whether you use CAD to
produce the final wire-book or not, your
gathering of bits and pieces into recipes
for success is STILL best accomplished
on paper with pencil. Multiple sheets of
paper.
Do your wirebook with a #2 pencil on a good
quality bond paper punched to fit a binder
of your choice. NEAT doesn't count. Get all
the parts, wires and layout down on paper
as the draft. Keep a soft eraser handy
(we call 'em Pink Pearls) to make clean
changes to your deliberations.
Do one-page-per-system. Landing light on one
page, starter on one page, alternator on
one page, etc. etc. No single page need
be very complex or cluttered with information.
When the details are all recorded, NOW decide
whether you want to convert it to a CAD
drawing.
Trying to do original work in CAD without
a high comfort level is like learning
to operate an 18-wheel truck to move some
materials around to build a tool shed for
your back yard. The CREATIVE efforts for
getting the simple-ideas of an electrical
system on paper are diluted and confused
by trying to describe your thoughts and
observations in a new language that commands
a very complex tool.
If you decide to jump to CAD, fine. Make
that a separate task for learning the language
that drives the new tool. Alternatively,
consider taking your 'draft' sheets and
using a indelible pen (I like ultra-fine
Sharpies) to convert your drafts to finished
drawings. Make a copy of your pencil draft
and convert it to hard lines with the
ink pen. If you like the first one, then
do it a second time on your pencil copy.
Then use the eraser to remove your pencil
draft.
Virtually all schematics I post to the List
or my website are evolved with this process.
http://tinyurl.com/k7cvegw
When you're working on your wirebook, the
end product can look even better than these
quickly crafted sketches.
I am reluctant to discourage anyone from acquiring
CAD skills . . . but I question the return on
investment for $time$ it takes to acquire
useful competency with a very powerful tool.
The job might be reduced to a couple
of hours with an pencil, good paper, ink pen
and a Pink Pearl.
Sometimes the best way to drive the nail
is with a hammer. But I will dig up and post
that list of CAD commands that any wannabe AutoCAD
driver will find useful as a study guide. It
is indeed a powerful tool. It has greatly enhanced
my own career path.
Hmmm . . . this might be expanded inot a good
article for KitPlanes . . .
Bob . . .
________________________________________________________________________________
| Subject: | Re: Copper Foil width for VOR antenna |
| From: | "user9253" <fransew(at)gmail.com> |
When the wires at each end of 300 ohm TV antenna twin lead are connected together,
the twin lead will have the same bandwidth as copper tape. Jim Weir has used
twin lead for some of his antennas.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410758#410758
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | EXP 2 Bus workaround |
Bob wrote:
> Which engine are we talking about?
...engine is from RAM Performance...it is a 140 hp multiport EFI
version of the dual port 115 hp EFI engine based on the Subaru EA81
block. Though the 115 hp engine was manufactured in runs of 50, the
multiport versions were (are?) custom made to order.
> Is there no supplier support?
...not much at present...company has relocated from Ohio to N.
Carolina...website is down, but owner, Ron Carr is available by phone.
> Is there a user's forum of individuals who are already flying?
...not that I am aware of, although I've found many favorable
endorsements on the web of Ron's knowledge and work on the web
....since the floods in CO, I've lost touch w/ Glenn Crowder who
is flying a Europa w/ a Sube which Ron rebuilt a few years ago.
It's probably fair to say that I have somewhat of an orphan
engine..
Back to the issue of the electrical load of the engine...for the
purposes of this discussion, I am quite content to use the figures Bill
Bradburry has posted, namely:
> EC2 and gauges: 0.8 A
> 2 leading coils: 2.4 A
> 2 trailing coils: 2.4 A
> 2 primary injectors 0.7 A
> 2 secondary injectors: 0.7 A
> 1 Mazda stock RX7 fuel pump: 3.8 A
>
> Total in normal running config: 10.8 A
Fred
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
At 07:52 PM 10/16/2013, you wrote:
>Hi Bob,
>After taking the EAA Sportair avionics workshop and learning about
>you, I'm now trying to identify the best wire-cutting and crimping
>tools to buy and I had a few questions I'd really like your opinion
>on, because I'm willing to spend on high quality tools but I'm not
>aware of the brands/models to consider .
>"Ideal Industries" makes a wire stripper called "Custom
>Stripmaster"; for avionics and mil-spec work with 'die-type' blades,
>described in your article. If I'm willing to spend $191, is this the
>best one to get, and are there other brands worth considering?
>Also, for terminal crimping I'm looking at 'Klein Tools T1710
>Compound-Action Ratcheting Crimper - Insulated Terminals' which
>crimps 10-22 AWG insulated terminals to "meet or exceed MIL-SPEC
>pull-out tests", costs $239.16. Is this a good choice or are there
>other mil-spec brands to consider?
>Your advice will be greatly appreciated.
Those tools are certainly top-notch and would serve
you well. If money is not a severe constraint, then
by all means acquire these tools. You're talking
$450 for some tools that may not see much service
after you've finished your airplane. Know that there
are many terminals being installed with much less
expensive tools. See:
http://tinyurl.com/kfk6jss
With some practice, Tefzel wires can be stripped with
a simple, $5 flush-cutter . . .
http://tinyurl.com/lv8jwe7
If you have the money to invest in top
shelf tools, go for it. But if learning to
do the job with $50 worth of tools leaves
you $400 to invest in an upgrade to your
GPS . . . or perhaps some nifty vaccinations
against Dark Panel Syndrome for the flight
bag . . .
http://tinyurl.com/d5mrjgh
. . . then perhaps a more detailed review
of your purchase goals is in order.
Join us on the AeroElectric-List . . . a forum
of about 1600 builders who are wrestling with
these same questions and many more every day.
http://tinyurl.com/57wytb
I think you'll find that time spent in this
forum will be very useful to you in the fabrication
of your airplane.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | A study guide for AutoCAD and clones |
Here is a re-posted note I published last year
on shortcuts in AutoCAD/NanoCAD and a study guide
for 99% of all the commands you'll ever need . . .
---------------------------------------------------------------
At 04:17 AM 6/16/2012, you wrote:
>
>I made drawings using Solid Edge. Months later when I tried to open
>the drawings, Solid Edge said that my license had expired. It would
>not let me look at my drawings unless I renewed my license
>(free). This happened again the following year.
> I got to thinking, what will happen if Solid Edge changes their
> licensing policy or if they go out of business? I will not be able
> to access my drawings. So I switched to TurboCad, although it is
> not very intuitive. I prefer programs that are easy to learn
> without having to read the help files.
>Joe
NanoCAD (or any of the AutoCADS) are
excellent solutions. They understand English.
If you want to draw a line say "line" and
then enter a from (intersection, nearest, tangent
midpoint, etc) then a to (same constellation of
options) while guiding to those terminations with
the mouse.
Further, AutoCAD and nanoCAD have .pgp 'overlay' files
that you can edit with an ordinary text editor like
notepad.
A, *ARC
AA, *AREA
AL, *ALIGN
AR, *ARRAY
BL, *BLOCK
BR, *BREAK
CI, *CIRCLE
C, *CHANGE
CH, *CHAMFER
CO, *COPY
D, *DIMSTYLE
DDI, *DIMDIAMETER
DED, *DIMEDIT
DI, *DIST
DT, *DTEXT
E, *ERASE
ED, *DDEDIT
EL, *ELLIPSE
EXIT, *QUIT
F, *FILLET
H, *HATCH
I, *INSERT
L, *LINE
LA, *LAYER
LE, *QLEADER
LI, *LIST
LT, *LINETYPE
LTS, *LTSCALE
M, *MOVE
MI, *MIRROR
O, *OSNAP
P, *PAN
PE, *PEDIT
PL, *PLINE
PG, *POLYGON
PU, *PURGE
R, *REDRAW
RE, *REGEN
RA, *RECTANGLE
RO, *ROTATE
S, *STRETCH
SO, *SOLID
T, *TRIM
V, *VIEW
WB, *WBLOCK
XP, *EXPLODE
XT, *EXTEND
Z, *ZOOM
When you enter the short command, the cad program
interprets it for the full command. I found
that I could draw left-handed with the mouse
while one-hand typing with the right and
go through the 'dance moves' with greater
rapidity than by accessing all those little
tool-bar boxes (most of which I didn't need/
use). In fact, I can turn all the tool-bars off
and have the full, un-clutered screen to work
on.
Aside from the isometric drawings I made for
illustrating the 'Connection, I've not found a
strong need for 3d drawings. If you need that
capability, I'm not a good source for advise.
Your personal .pgp file becomes a good teaching
tool too. Out of hundreds of commands that the
CAD program understands, editing your overlay file
down to those you use 99% of the time make the .pgp
file a sort of syllabus for a short course in
AutoCAD. Search the 1-inch thick book of 1000
commands for how these few work . . . you'll have
99% of your dance moves learned in a very
short time.
In fact, I would recommend that anyone wanting to
get their feet wet in either AutoCAD or microCAD
cut-n-paste the list above into a new version of
a .pgp file and print a paper copy too. Hang it
on the wall behind your monitor as a reference
list. This will steepen your learning curve
greatly. You can always add/delete commands to
customize the list to your own needs but I'm
betting that becoming proficient in those
listed will get you up to speed very quickly.
Turning off all the tool bars and talking to
the program in 'English' is about as intuitive
as you can get. Over the years I've spent thousands
of dollars of both my and the boss's money on AutoCAD
and sundry upgrades. NanoCAD now does everything that used
to cost us the price of a good used car . . . for free.
Interestingly enough, NONE of those upgrades added
features that I needed for my work. Everything
I do today can be done in say AutoCAD R10 for
DOS!
There may be other applications that are as
intuitive and/or attractively priced . . . don't
know. But I can tell you that NanoCAD is an
exceedingly good value and easy to learn if you
start with the few dozen commands I listed
above.
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Battery busses in a fiberglass airframe |
All,
For weight and balance reasons, my battery-(ies) will be in the tailcone of my
Europa fiberglass airframe which includes a non-metallic firewall.
Battery ground wires will run forward to ground on the engine.
With an EFI'ed engine, I will have battery busses to carry all circuits essential
to keeping the engine running (fuel pumps, ECU, fuel injectors, and coils).
For convenience and accessibility, I want those busses forward...on the engine
side of the firewall. On a related matter, I would prefer the battery contactors
to be located on the engine side of the firewall.
I understand that customary practice is to keep the contactors adjacent to the
batteries, and to minimize the length of "hot" wires connected directly to the
batteries.
What I'm wondering is whether or not having a non-conductive airframe sufficiently
mitigates the risks which customary practice is intended to minimize...?...
Is there anyone out there who is flying a fiberglass airplane w/ rear mounted battery
and dealt with these issues?
...all comments appreciated...
Fred
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Battery busses in a fiberglass airframe |
At 03:04 PM 10/17/2013, you wrote:
>
>All,
>
>For weight and balance reasons, my battery-(ies) will be in the
>tailcone of my Europa fiberglass airframe which includes a
>non-metallic firewall.
>
>Battery ground wires will run forward to ground on the engine.
You can do this on one ground wire (between a battery(-)
common point for both batteries in tail) and a
recommended ground block on the firewall.
>With an EFI'ed engine, I will have battery busses to carry all
>circuits essential to keeping the engine running (fuel pumps, ECU,
>fuel injectors, and coils).
>
>For convenience and accessibility, I want those busses forward...on
>the engine side of the firewall. On a related matter, I would prefer
>the battery contactors to be located on the engine side of the firewall.
After studying your engine description I don't
think these 'engine busses' are going to be all
that complicated. I'm 10 minutes from hitting the
road for Wichita . . . I'll elaborate more Saturday
when I get back.
>I understand that customary practice is to keep the contactors
>adjacent to the batteries, and to minimize the length of "hot" wires
>connected directly to the batteries.
Yes.
>What I'm wondering is whether or not having a non-conductive
>airframe sufficiently mitigates the risks which customary practice
>is intended to minimize...?...
>
>Is there anyone out there who is flying a fiberglass airplane w/
>rear mounted battery and dealt with these issues?
Depends on what you mean by "dealt with these issues".
What are the perceived gains for moving the contactors?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
...not much at present...company has relocated from Ohio to N.
Carolina...website is down, but owner, Ron Carr is available by phone.
Is there any reason to believe that the hopped up
version of the engine needs any greater electrical
energy for operation than the 115 hp version?
Back to the issue of the electrical load of the engine...for the
purposes of this discussion, I am quite content to use the figures
Bill Bradburry has posted, namely:
EC2 and gauges: 0.8 A
2 leading coils: 2.4 A
2 trailing coils: 2.4 A
2 primary injectors 0.7 A
2 secondary injectors: 0.7 A
1 Mazda stock RX7 fuel pump: 3.8 A
Total in normal running config: 10.8 A
Good starting points. I'll be back Saturday.
Bob . . .
________________________________________________________________________________
| From: | "Sacha" <uuccio(at)gmail.com> |
| Subject: | To CAD or not to CAD . . . that is the question |
-->
Whether you use CAD to
produce the final wire-book or not, your
gathering of bits and pieces into recipes
for success is STILL best accomplished
on paper with pencil. Multiple sheets of
paper.
Thank you for the advice, I'm sure those words are wise ones... I'm curious
about CAD so I think I will eventually put the effort in and learn it
(thanks to the two people on the list who offered to relay a shipment of
TurboCAD to me ... I absolutely love this list...). But for the moment I
will draw everything out in pencil and paper as you suggest.
________________________________________________________________________________
| Subject: | New Aero-Electric Manual |
| From: | "H. Marvin Haught" <handainc(at)madisoncounty.net> |
Bob -
I am starting on a new project and getting my reference materials organized. I
have an old copy of the Aero-Electric Manual. When will the new edition be out
and what is the cost? I will send you a check to get one on order once copies
are available.
M. Haught
P.O. Box 419
Huntsville, AR 72740
________________________________________________________________________________
| Subject: | Re: Copper Foil width for VOR antenna |
| From: | "p32gxy" <p32gxy(at)gmail.com> |
kuffel(at)cyberport.net wrote:
>
> We have reached the point where we need more information. Are you talking Rutan
moldless composite construction or premolded skins a la
> Lancair/Glasair?
>
The wing is all finished, using premolded skins. This is a retrofit as the original
builder did not see the need to put in a VOR antenna. I only have access
to the inside of the wing through the pitot service door (small)... not a lot
of room to work with... which is the reason why I have been attracted to the copper
foil antenna which can be mounted on the "outer" surface of the wing.
Theory notwithstanding, I don't like to drill holes in structural elements... call
me crazy... unless there is absolutely no other way. For me, this thread is
about finding the other way :-)
I am even considering the Dave Morris Loop antenna (http://www.davemorris.com/MorrisComLoop.cfm), adapted to the NAV band I calculate a 29.5" diameter for the loop... I could fit such a loop on the underside of the fuselage and avoid the complications of wing based antennae...placement supposedly is not so critical as with the "V" shaped when it comes to proximity to other metal elements... then again this is all theory for me as I have no experience with loop antennae.
kuffel(at)cyberport.net wrote:
>
> The purpose of making the legs Vee shaped is to remove the null reception points
off the ends of a straight dipole. But you don't need 45 degree bends to
do this. A much shallower angle will still give adequate
> performance. And there is no problem with curlling the tips somewhat near the
leading edge.
>
>
The location and available space is less than ideal... I do try to avoid curling
the tips or getting them within 1/4 wave length of metallic wires/tubes, etc.
due to the tips being more the sensitive end of the assembly from a placement
standpoint... the best angle I'll be able to do is 120 deg between the legs.
kuffel(at)cyberport.net wrote:
>
> Understand we don't need the last db of signal strength in this application.
> In a composite fuselage a 23" length of wire dangling from the center
> conductor on the back of the radio would still give "adequate performance".
>
I am not sure i agree with the basic principle inherent in this statement (I keep
hearing a lot). While i agree that some of the "optimizations" don't have an
adequate reward ratio, I still try to do the best job I can under the circumstances.
If and when I cut corners, I want to do so fully understanding the tradeoffs
(and risks if any) so that i can make informed decisions.
Coax is a typical example... I am spending x6 the $$ to get RG400 rather than RG58U
being fully aware of all the arguments that from a sheer dB loss standpoint,
the difference will not be practically noticeable... the extra shielding however
is not just a matter of dB loss (in my eyes)... interference from strobes,
etc. comes to mind.
Thanks for all the posts... keep them coming !!!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410773#410773
________________________________________________________________________________
| Subject: | Re: Copper Foil width for VOR antenna |
| From: | "p32gxy" <p32gxy(at)gmail.com> |
user9253 wrote:
> When the wires at each end of 300 ohm TV antenna twin lead are connected together,
the twin lead will have the same bandwidth as copper tape. Jim Weir has
used twin lead for some of his antennas.
> Joe
Not familiar with this technique... theorizing here... the effective performance
depends on distance between leads, dielectric type, etc... this type of antenna
would have to be seriously tuned post installation...
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410776#410776
________________________________________________________________________________
| From: | "The Kuffels" <kuffel(at)cyberport.net> |
| Subject: | Re: Copper Foil width for VOR antenna |
<< copper foil antenna which can be mounted on the "outer" surface of the
wing... don't like to drill holes in structural elements >>
So the plan would be to drill 2 tiny holes in the wing skin and feed
pigtails through them for connection to the coax/balun? Or is it to have
the center of the Vee even with the rear edge with the cable in the aileron
slot for feeding to the wing interior perhaps via an existing gap?
<< Dave Morris Loop antenna >>
This is an excellent antenna, best if mounted horizontally as you propose.
RG-59 will work for the matching line. Depending on conditions you might
need to replace the tuning section every 10 to 15 years or so. The local
amateur radio club (see ARRL.org) can get you access to an antenna analyzer
which will tell you the condition of the antenna.
The effects of the rudder cables and elevator control are unknown. Not as
visually hidden but the top of the fuselage might work better electrically.
<< > In a composite fuselage a 23" length of wire dangling from the center
> conductor on the back of the radio would still give "adequate
> performance".
I am not sure i agree with the basic principle inherent in this statement >>
Try it, it is a simple, easy experiment.
<< RG400 rather than RG58U >>
For me the RG400 is worth the cost. Besides the lower loss and much better
shielding which you mention, RG400 is much more stable over time. I've seen
some really ratty RG58 come out of older airplanes over the years. Shocking
the radio still worked at all (see 23" dangling wire above).
Tom Kuffel
________________________________________________________________________________
| Subject: | Re: Copper Foil width for VOR antenna |
| From: | "p32gxy" <p32gxy(at)gmail.com> |
kuffel(at)cyberport.net wrote:
>
> So the plan would be to drill 2 tiny holes in the wing skin and feed
> pigtails through them for connection to the coax/balun? Or is it to have
> the center of the Vee even with the rear edge with the cable in the aileron
> slot for feeding to the wing interior perhaps via an existing gap?
>
2 tiny holes and feed pigtails to the balun which will be coiled up in an inside
space.
kuffel(at)cyberport.net wrote:
>
>
> This is an excellent antenna, best if mounted horizontally as you propose.
> RG-59 will work for the matching line. Depending on conditions you might need
to replace the tuning section every 10 to 15 years or so. The local amateur
radio club (see ARRL.org) can get you access to an antenna analyzer which will
tell you the condition of the antenna.
>
I have been researching loop antennas as I do like the small footprint, omni-directionality,
etc. What I am finding so far sounds very good... I am looking for
the gotcha... why are they not popular if they are so good?
The only answer I am able to come up with thus far is that impedance matching seems
too complicated for most people, you do need to invest in an SWR meter for
proper tuning! In other words you do need some background/experience in RF engineering.
kuffel(at)cyberport.net wrote:
>
> The effects of the rudder cables and elevator control are unknown. Not as visually
hidden but the top of the fuselage might work better electrically.
>
As i understand this particular challenge... any long conductor near the loop should
theoretically act as a reflector, which means in that direction the reception
will be affected. Worst case, one may have a dead spot if the conductive
element (rudder cable/elevator controls) are near the antenna's plane. Loop antenna
or not, the effects are the same ... am I missing something?
The top of the fuselage is indeed further removed from most elements which would
interfere with the antenna (except for the salty water in my head). Considering
that a loop antenna in that location is full wavelength with a minimum of
1dB of gain... I believe I will investigate the possibility of placing the loop
antenna there. For the loop antenna, I could use regular Tefzel wire and mount
the whole thing on the inside :-)
I will have to curve the whole antenna downward to match the curvature of the fuselage,
but this should have minimal effect on performance, especially if using
a Delta Loop (3 sided triangular loop) as this would allow me to angle the
tip backwards with the widest part of the loop placed in the widest section of
the fuselage.
kuffel(at)cyberport.net wrote:
>
> In a composite fuselage a 23" length of wire dangling from the center conductor
on the back of the radio would still give "adequate performance".
>
> Try it, it is a simple, easy experiment.
>
Technically a wet string would work... that doesn't mean I want to use wet strings
in my airplane :-)... I do find the irony in it though... millions are spent
on antenna design... when wet noodles would do the trick :-)
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410783#410783
________________________________________________________________________________
| From: | Eric Page <edpav8r(at)yahoo.com> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
Some months ago I bought a brand new Ideal Stripmaster (is the "Custom" a different
tool?) on eBay for around $30. I also got an additional die set for larger
wires for around $12. It chews up Tefzel insulation like nobody's business.
It works so well I giggled the first time I used it!
Ideal makes several models of Stripmaster, the difference being the factory-installed
die set. I just worked out the best overlap between dies/wire sizes and
purchased accordingly.
At about the same time, I bought a full-cycle ratcheting crimper with five or six
sets of quick-change crimping dies in a nice blow-mold case for around $50.
Quality appears high and it works beautifully.
I just started a 3-day trip today; I can post exact make/model on these items Fri
evening.
Eric
On Oct 17, 2013, at 12:47 PM, "Robert L. Nuckolls, III"
wrote:
>
> At 07:52 PM 10/16/2013, charluzze wrote:
>> Hi Bob,
>> After taking the EAA Sportair avionics workshop and learning about you, I'm
now trying to identify the best wire-cutting and crimping tools to buy and I had
a few questions I'd really like your opinion on, because I'm willing to spend
on high quality tools but I'm not aware of the brands/models to consider .
>> "Ideal Industries" makes a wire stripper called "Custom Stripmaster"; for avionics
and mil-spec work with 'die-type' blades, described in your article. If
I'm willing to spend $191, is this the best one to get, and are there other brands
worth considering?
>> Also, for terminal crimping I'm looking at 'Klein Tools T1710 Compound-Action
Ratcheting Crimper - Insulated Terminals' which crimps 10-22 AWG insulated terminals
to "meet or exceed MIL-SPEC pull-out tests", costs $239.16. Is this a
good choice or are there other mil-spec brands to consider?
>> Your advice will be greatly appreciated.
>
> Those tools are certainly top-notch and would serve
> you well. If money is not a severe constraint, then
> by all means acquire these tools. You're talking
> $450 for some tools that may not see much service
> after you've finished your airplane. Know that there
> are many terminals being installed with much less
> expensive tools. See:
>
> http://tinyurl.com/kfk6jss
>
> With some practice, Tefzel wires can be stripped with
> a simple, $5 flush-cutter . . .
>
> http://tinyurl.com/lv8jwe7
>
> If you have the money to invest in top
> shelf tools, go for it. But if learning to
> do the job with $50 worth of tools leaves
> you $400 to invest in an upgrade to your
> GPS . . . or perhaps some nifty vaccinations
> against Dark Panel Syndrome for the flight
> bag . . .
>
> http://tinyurl.com/d5mrjgh
>
> . . . then perhaps a more detailed review
> of your purchase goals is in order.
>
> Join us on the AeroElectric-List . . . a forum
> of about 1600 builders who are wrestling with
> these same questions and many more every day.
>
> http://tinyurl.com/57wytb
>
> I think you'll find that time spent in this
> forum will be very useful to you in the fabrication
> of your airplane.
>
> Bob . . .
________________________________________________________________________________
| From: | Jeff Luckey <jluckey(at)pacbell.net> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
My .02=0A=0AI recently bought a new wire stripper from Klein Tools:=0Ahttp:
//www.amazon.com/Klein-Tools-11063-Katapult-Stripper/dp/B0035KF232=0A=0AIt'
s a pretty standard one-squeeze unit with very good quality.- I bought mi
ne from the local electrical wholesaler for about $25.- A word of caution
- it is fairly easy to nick the copper w/ these.- You must be careful to
CENTER the wire in the proper cutting slot for your size wire.- Very oft
en I strip wire using the slot for the next size up wire.- In other words
, when stripping 22 AWG wire, I put it in the #20 slot.=0A=0AWhen you get g
ood at using this tool it is very fast.- Replacement blades are about $15
.- All-in-all a good tool at a good value.=0A=0A=0A=0A=0A=0A=0A__________
______________________=0A From: "Robert L. Nuckolls, III" <nuckolls.bob@aer
oelectric.com>=0ATo: charluzze =0ASent: Thursday, Oct
ober 17, 2013 12:47 PM=0ASubject: AeroElectric-List: Re: EAA SPORTAIR Works
"Robert L. Nuckolls, III" =0A=0AAt 07:52 PM
10/16/2013, you wrote:=0A> Hi Bob,=0A> After taking the EAA Sportair avion
ics workshop and learning about you, I'm now trying to identify the best wi
re-cutting and crimping tools to buy and I had a few questions I'd really l
ike your opinion on, because I'm willing to spend on high quality tools but
I'm not aware of the brands/models to consider .=0A> "Ideal Industries" ma
kes a wire stripper called "Custom Stripmaster"; for avionics and mil-spec
work with 'die-type' blades, described in your article. If I'm willing to s
pend $191, is this the best one to get, and are there other brands worth co
nsidering?=0A> Also, for terminal crimping I'm looking at 'Klein Tools T171
0 Compound-Action Ratcheting Crimper - Insulated Terminals' which crimps 10
-22 AWG insulated terminals to "meet or exceed MIL-SPEC pull-out tests", co
sts $239.16. Is this a good choice or are there other mil-spec brands to co
nsider?=0A> Your advice will be greatly appreciated.=0A=0A- Those tools
are certainly top-notch and would serve=0A- you well. If money is not a
severe constraint, then=0A- by all means acquire these tools. You're tal
king=0A- $450 for some tools that may not see much service=0A- after
you've finished your airplane. Know that there=0A- are many terminals be
ing installed with much less=0A- expensive tools.- See:=0A=0Ahttp://ti
nyurl.com/kfk6jss=0A=0A- With some practice, Tefzel wires can be strippe
d with=0A- a simple,- $5 flush-cutter . . .=0A=0Ahttp://tinyurl.com/lv
8jwe7=0A=0A- If you have the money to invest in top=0A- shelf tools,
go for it. But if learning to=0A- do the job with $50 worth of tools lea
ves=0A- you $400 to invest in an upgrade to your=0A- GPS . . . or per
haps some nifty vaccinations=0A- against Dark Panel Syndrome for the fli
ght=0A- bag . . .=0A=0Ahttp://tinyurl.com/d5mrjgh=0A=0A- . . . then p
erhaps a more detailed review=0A- of your purchase goals is in order.=0A
=0A- Join us on the AeroElectric-List . . . a forum=0A- of about 1600
builders who are wrestling with=0A- these same questions and many more
every day.=0A=0Ahttp://tinyurl.com/57wytb=0A=0A- I think you'll find tha
t time spent in this=0A- forum will be very useful to you in the fabrica
==============
________________________________________________________________________________
| Subject: | Re: Relay for Critical Power Feed |
| From: | Thomas E Blejwas <tomblejwas(at)yahoo.com> |
Yes, this does look like a better choice for the feed to my ECU. For my fuel pumps,
I think having each pump connected to a different engine bus is a simpler
way to go.
Tom
Sent from my iPad
________________________________________________________________________________
| From: | rayj <raymondj(at)frontiernet.net> |
| Subject: | Teledyne stripall |
Greetings,
I just picked up a used Teledyne stripall and I'm hoping someone can
help me with determining whether it works or not. It doesn't have any
blades and I'd like to verify it works before I order blades.
I assume I should have some voltage across some of the terminals. If
anyone could tell me what those values should be I would appreciate it.
If anyone could direct me to a copy of the instructions and/or a repair
manual, that would also be appreciated.
Thanks in advance.
--
Raymond Julian
Kettle River, MN.
"And you know that I could have me a million more friends,
and all I'd have to lose is my point of view." - John Prine
________________________________________________________________________________
| From: | "Sacha" <uuccio(at)gmail.com> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
I recently bought a new wire stripper from Klein Tools:
http://www.amazon.com/Klein-Tools-11063-Katapult-Stripper/dp/B0035KF232
It's a pretty standard one-squeeze unit with very good quality. I bought
mine from the local electrical wholesaler for about $25. A word of caution
- it is fairly easy to nick the copper w/ these. You must be careful to
CENTER the wire in the proper cutting slot for your size wire. Very often I
strip wire using the slot for the next size up wire. In other words, when
stripping 22 AWG wire, I put it in the #20 slot.
When you get good at using this tool it is very fast. Replacement blades
are about $15. All-in-all a good tool at a good value.
Hi Jeff,
I bought the same tool a few months ago. But I am reluctant to use it
because I have difficulty in using it properly: it strips the insulation off
the wire fine, but when I open the handles to release the wire, I find that
it holds onto the insulated part and then the "claws" then ruin the copper
strands by squashing them. Its nothing major, but then I have to go and
twist the strands together again by hand.
Do you have the same problem? Is there a way to set it so it doesn't do
that?
Sacha
________________________________________________________________________________
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
| From: | Dave Saylor <dave.saylor.aircrafters(at)gmail.com> |
I know exactly the problem you're describing. I think you'll find that if
you just release the handles a little more slowly that the grip will
release the wire before the blades can smack the freshly stripped section.
> Hi Jeff,****
>
> I bought the same tool a few months ago. But I am reluctant to use it
> because I have difficulty in using it properly: it strips the insulation
> off the wire fine, but when I open the handles to release the wire, I fin
d
> that it holds onto the insulated part and then the =9Cclaws
=9D then ruin the
> copper strands by squashing them. Its nothing major, but then I have to
go
> and twist the strands together again by hand.****
>
> Do you have the same problem? Is there a way to set it so it doesn
=99t do
> that?****
>
> Sac
>
> *_*
>
>
--
--Dave Saylor
________________________________________________________________________________
| From: | Lynn Cole <LynnCole(at)foxvalley.net> |
| Subject: | Re: Copper Foil width for VOR antenna |
Why not use some fiberglas to laminate the sheath into the wing in the
position where you want it?
-----
Lynn Cole
LynnCole(at)foxvalley.net
On Oct 16, 2013, at 6:27 PM, p32gxy wrote:
>
> I am loving the idea of a protective sheath/tube to achieve mechanical
isolation...
> Unfortunately, i don't see how I can make use of this approach without
either drilling holes in the spar or messing up the wing's shape/airflow
>
> The VOR antenna I can install has to be flat so that it integrates
into the wing surface. Don't want to be compromising the wing skin...
moving the antenna is also not an option because the only place I can
keep the tips away from "metal" antennae like structures is in the
outboard 1/3 of the wing.
>
> I am all open to suggestions and will consider anything and everything
including novel designs and unusual shapes as I am finding that the
22.8" per leg of the V shaped antennae is hard to place without
interference.... please keep them comming.
>
> Thx.
>
>
> nuckolls.bob(at)aeroelect wrote:
>> At 04:26 PM 10/15/2013, you wrote
>> The problem with embedded antennas is the potential for
>> fatigue failure of the conductors if the composite
>> structure flexes. This can produce hairline fractures
>> in foil or wire antennas bonded to a composite surface. It can
>> make your antenna conductors look like the wires in a strain
>> guage . . . that stretch and compress as the surface responds
>> to structure flexing.
>>
>> RF bandwidth of the wider foil is attractive but as mentioned
>> here, insignificant with respect to performance. Consider an
>> ALL COAX antenna assembly. Balun is optional . . . cool
>> but performance difference is very small. Making the
>> antenna elements from coax braid FLOATING INSIDE a piece of 1/4"
>> Nylon tubing will get you a simple antenna material,
>> adequate performance and the tubing isolates the antenna
>> from structure so that flexing doesn't mechanically irritate
>> the elements.
>>
>>
>> Bob . . .
>
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=410717#410717
>
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
| From: | Jeff Luckey <jluckey(at)pacbell.net> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
=0A=0AI've not had that problem, but the suggestion below is probably a goo
d one.=C2- Also, I always give the strands of a freshly stripped end a go
od twisting - it makes insertion into the wire terminal easier.=C2- I'm n
ot aware of any settings or adjustments on the tool that would help.=0A=0A
=0A-J=0A=0A=0A________________________________=0A From: Dave Saylor <dave.s
aylor.aircrafters(at)gmail.com>=0ATo: "aeroelectric-list(at)matronics.com" =0ASent: Friday, October 18, 2013 7:21 AM=0ASub
ject: Re: AeroElectric-List: Re: EAA SPORTAIR Workshop attendee has questio
n=0A =0A=0A=0AI know exactly the problem you're describing. I think you'll
find that if you=C2-just=C2-release the handles a little more slowly th
at the grip=C2-will release the wire before the blades can smack the fres
hly stripped section.=C2-=0AHi Jeff,=0A>I bought the same tool a few mont
hs ago.=C2- But I am reluctant to use it because I have difficulty in usi
ng it properly: it strips the insulation off the wire fine, but when I open
the handles to release the wire, I find that it holds onto the insulated p
art and then the =9Cclaws=9D then ruin the copper strands by sq
uashing them. =C2-Its nothing major, but then I have to go and twist the
strands together again by hand.=0A>Do you have the same problem? Is there a
way to set it so it doesn=99t do that?=0A>Sac=0A>_ =0A=0A-- =0A--Dav
========================
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | elec. noise in antennas |
All,
I have been diligent in separating antenna wiring from power wiring...in my fiberglass
airframe, I molded in conduits along the sides of the fuselage...all power
wiring on the port side...antenna wiring and pneumatics on starboard.
My port conduit is getting pretty filled, and I have ample space in the stbd conduit.
With my batteries mounted aft, I have 2AWG feed to the starter and a 2 AWG ground
wire from battery to engine.
So here's a question:
Since the feed to the starter is only passing current when the starter contactor
is closed, can I run its feed along w/ my RG58 com and xpndr antenna wires?...or
will the mere presence of the starter feed (all that metal!) alongside the
antenna wires degrade my reception and transmissions?
And...am I correct in reasoning that the 2AWG ground wire definitely needs to stay
away from those antenna wires?
thanks for your insights,
Fred
________________________________________________________________________________
| From: | John W Livingston <livingjw(at)earthlink.net> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
I believe its better not to twist the wires before insertion into a
crimp terminal. Better gas tight crimp.
JWL
On 10/18/2013 1:39 PM, Jeff Luckey wrote:
>
> I've not had that problem, but the suggestion below is probably a good
> one. Also, I always give the strands of a freshly stripped end a good
> twisting - it makes insertion into the wire terminal easier. I'm not
> aware of any settings or adjustments on the tool that would help.
>
> -J
> ------------------------------------------------------------------------
> *From:* Dave Saylor
> *To:* "aeroelectric-list(at)matronics.com"
> *Sent:* Friday, October 18, 2013 7:21 AM
> *Subject:* Re: AeroElectric-List: Re: EAA SPORTAIR Workshop attendee
> has question
>
> I know exactly the problem you're describing. I think you'll find that
> if you just release the handles a little more slowly that the
> grip will release the wire before the blades can smack the freshly
> stripped section.
>
> Hi Jeff,
> I bought the same tool a few months ago. But I am reluctant to
> use it because I have difficulty in using it properly: it strips
> the insulation off the wire fine, but when I open the handles to
> release the wire, I find that it holds onto the insulated part and
> then the claws then ruin the copper strands by squashing them.
> Its nothing major, but then I have to go and twist the strands
> together again by hand.
> Do you have the same problem? Is there a way to set it so it
> doesnt do that?
> Sac
>
> *_
> *
>
>
> --
> --Dave Saylor
> *
>
>
> *
________________________________________________________________________________
| Subject: | Re: elec. noise in antennas |
| From: | Tim Andres <tim2542(at)sbcglobal.net> |
Is this a pusher with the engine and battery aft?
In either case, some separation is good insurance, more is better where possible.
Less so if your using good coax like RG 400.
I'd suggest just do the best you can to keep them apart at least a couple of inches.
The 2AWG ground will be busy when you crank like you said, but if you have
an alternator or electronic ignition or engine monitoring system it could have
30-40 amps on it at times after start, probably 8-12 or so on it after the
battery is charged. I'd still keep apart as far as is reasonably possible.
Just one opinion...
Tim
All spelling errors are Apples responsibility.
> On Oct 18, 2013, at 11:04 AM, Fred Klein wrote:
>
>
> All,
>
> I have been diligent in separating antenna wiring from power wiring...in my fiberglass
airframe, I molded in conduits along the sides of the fuselage...all
power wiring on the port side...antenna wiring and pneumatics on starboard.
>
> My port conduit is getting pretty filled, and I have ample space in the stbd
conduit.
>
> With my batteries mounted aft, I have 2AWG feed to the starter and a 2 AWG ground
wire from battery to engine.
>
> So here's a question:
>
> Since the feed to the starter is only passing current when the starter contactor
is closed, can I run its feed along w/ my RG58 com and xpndr antenna wires?...or
will the mere presence of the starter feed (all that metal!) alongside
the antenna wires degrade my reception and transmissions?
>
> And...am I correct in reasoning that the 2AWG ground wire definitely needs to
stay away from those antenna wires?
>
> thanks for your insights,
>
> Fred
>
>
>
>
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: elec. noise in antennas |
On Oct 18, 2013, at 12:19 PM, Tim Andres wrote:
> Is this a pusher with the engine and battery aft?
Tim...to clarify, my engine is a tractor (forward) w/ battery aft...Fred
________________________________________________________________________________
| From: | "John Evens" <jrevens(at)comcast.net> |
I purchased some very nice DC-rated Mil-spec Honeywell switches
(#MS24523-23) to use as ignition switches with my Rotax powered
Kitfox. In checking the spec sheet after the fact, I see that they
have "silver cadmium oxide" contacts. Then there is a statement that
"non-arcing loads (generally less than 12v & 0.5 amps) are not
recommended" with silver cadmium oxide contacts. Can anyone tell me if
using these style switches with the silver cadmium oxide points, for
ignition (or master switches with the DPDT version), would be
acceptable & prudent?
John Evens
________________________________________________________________________________
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
| From: | Sacha <uuccio(at)gmail.com> |
> I believe its better not to twist the wires before insertion into a crimp t
erminal. Better gas tight crimp.
Yup. Also better not to touch the strands if you're going to be soldering. A
t least according to the NASA guide.
>>
>> I know exactly the problem you're describing. I think you'll find that if
you just release the handles a little more slowly that the grip will releas
e the wire before the blades can smack the freshly stripped section.
I tried doing it slower but had no success. I'll give it another try when do
wn at the hangar again.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: elec. noise in antennas |
At 01:04 PM 10/18/2013, you wrote:
>
>All,
>
>I have been diligent in separating antenna wiring from power
>wiring...in my fiberglass airframe, I molded in conduits along the
>sides of the fuselage...all power wiring on the port side...antenna
>wiring and pneumatics on starboard.
>
>My port conduit is getting pretty filled, and I have ample space in
>the stbd conduit.
There is no demonstrable value in separating antenna
coax wires and other ship's wiring. The idea that
'noise' escapes ships wiring to invade the inner-sanctum
of your coax is a poplar myth morphed into sage advice.
>With my batteries mounted aft, I have 2AWG feed to the starter and a
>2 AWG ground wire from battery to engine.
How do you know htat you need 2AWG feeders?
How long are your battery-to-firewall runs?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Switch question |
At 04:12 PM 10/18/2013, you wrote:
>I purchased some very nice DC-rated Mil-spec Honeywell switches
>(#MS24523-23) to use as ignition switches with my Rotax powered
>Kitfox. In checking the spec sheet after the fact, I see that they
>have "silver cadmium oxide" contacts. Then there is a statement that
>"non-arcing loads (generally less than 12v & 0.5 amps) are not
>recommended" with silver cadmium oxide contacts. Can anyone tell me
>if using these style switches with the silver cadmium oxide points,
>for ignition (or master switches with the DPDT version), would be
>acceptable & prudent?
>
> John Evens
Yes, I don't understand that admonition in
in the spec sheet. Did you find that on the
'net? Very few applications for toggle switches
are free of arcing. The degree by which arcing
is generated can be all over the map but in your
airplane, the worst case loads that might exist . . .
paired with the exceedingly low duty cycle for
switches in light aircraft do not pose any
threat of premature failure due to overloading.
Can you sent me a copy of the spec sheet or
a link for downloading it?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Switch question !!!OOPS!!!! |
At 04:12 PM 10/18/2013, you wrote:
>I purchased some very nice DC-rated Mil-spec Honeywell switches
>(#MS24523-23) to use as ignition switches with my Rotax powered
>Kitfox. In checking the spec sheet after the fact, I see that they
>have "silver cadmium oxide" contacts. Then there is a statement that
>"non-arcing loads (generally less than 12v & 0.5 amps) are not
>recommended" with silver cadmium oxide contacts. Can anyone tell me
>if using these style switches with the silver cadmium oxide points,
>for ignition (or master switches with the DPDT version), would be
>acceptable & prudent?
>
> John Evens
Yes, I don't understand that admonition in
in the spec sheet. Did you find that on the
'net? Very few applications for toggle switches
are free of arcing. The degree by which arcing
is generated can be all over the map but in your
airplane, the worst case loads that might exist . . .
paired with the exceedingly low duty cycle for
switches in light aircraft do not pose any
threat of premature failure due to overloading.
Can you sent me a copy of the spec sheet or
a link for downloading it?
Had a momentary case of keyboard-in-mouth disease.
Meeting design life with switches/relays with
silver-cad ASSUMES some degree of arcing to help
burn away corrosion. Non-Arcing is sometimes
referred to as 'dry contact' switching too. Switches/
and relays working in these tiny loads generally
have gold plated contacts . . . no corrosion . . .
but don't hit them with an arcing load or you
burn away the gold and convert the thing to a
really bad, dry-circuit switch.
Short answer is yes, those switches are entirely
suitable for use on your airplane. There is a
very SMALL possibility that they'll 'go open'
because they're not used enough . . . I.e.
a special application switch that is not routinely
used.
Found this in a Beechjet once. It was in some kind
of seldom used press to test function. The tech was
headed off the stockroom to get a new switch.
I told him to hold off. Got a bench supply that
I set up for 28v at 3A constant current and used
the open swicth to 'short out' the power supply.
I wiggled the switch a couple dozen times and rechecked
it with a micro-ohmmeter. Contacts were restore to like
new.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
>Hi Jeff,
>I bought the same tool a few months ago. But I
>am reluctant to use it because I have difficulty
>in using it properly: it strips the insulation
>off the wire fine, but when I open the handles
>to release the wire, I find that it holds onto
>the insulated part and then the =9Cclaws=9D then
>ruin the copper strands by squashing them. Its
>nothing major, but then I have to go and twist
>the strands together again by hand.
>Do you have the same problem? Is there a way to
>set it so it doesn=99t do that?
>Sac
Emacs!
The tool you linked is a clone of the Ideal Industries Stripmaster.
I have excerpted a few parts from the spare parts catalog. Check
your tool for Item 8 and it's associated spring Item 9. If the spring
is too weak or missing, you will experience the late release phenomenon
you describe. On old tools, the cam-notch in the latch wears and
can cause the same problem.
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: elec. noise in antennas |
On Oct 18, 2013, at 4:40 PM, Robert L. Nuckolls, III wrote:
>>
>> With my batteries mounted aft, I have 2AWG feed to the starter and a
2 AWG ground wire from battery to engine.
>
> How do you know htat you need 2AWG feeders?
> How long are your battery-to-firewall runs?
Bob...thanks for asking...
I don't in fact "know" that I need 2 AWG feeders...I used that size
solely for the purpose of emphasizing that the problem I was facing was
caused by some VERY large wires; I note however that Z-19RB calls for
2AWG feeder from battery contactor to starter contactor.
My "battery-to-firewall runs" are exactly 9 feet; firewall to starter is
another 3 to 4 feet.
Fred
PS: Thanks for dispelling one more myth!
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: elec. noise in antennas |
>I don't in fact "know" that I need 2 AWG feeders...I used that size
>solely for the purpose of emphasizing that the problem I was facing
>was caused by some VERY large wires; I note however that Z-19RB
>calls for 2AWG feeder from battery contactor to starter contactor.
>
>My "battery-to-firewall runs" are exactly 9 feet; firewall to
>starter is another 3 to 4 feet.
>
>Fred
Understand. Recall that the Z-Figures are ARCHITECTURE drawings
and that wire gauge callouts need to be validated against
the real needs of your proposed system. Let's do a little
sharp pencil work with your FAT wires:
4AWG wire has a resistance of 300 micro-ohms per foot. Your
FAT wire engine cranking loop is 24 feet log. This means
that the loop resistance in wire is on the order of 300 x
24 = 7200 micro ohms or 7.2 milli ohms. Assume a difficult
cranking event at 200A for your proposed engine. 200 x .0072
= 1.4 volts drop. You've got 2 RG batteries in parallel with
something on the order of 7 milliohms each or 3.5 milliohms
paralleled for cranking. 200A tosses off an additional 0.7
volts at the battery terminals.
A rule of thumb target for terminal voltage at the starter
is 9.0 volts. Starting with 12.5 volt battery
we give up 1.4 volts in wire at 0.7 volts at the batteries
This says we can toss off another 1.4 volts in contactors,
terminals and bolted joints. Seems like ample head-room.
Your FAT wire runs are analogous to cranking somebody else's
car on a cold morning with a 12' long set of jumper cables
fabricated from 4AWG wire. The first hi-performance set
of jumper cables I built were made of 2AWG welding cable . . .
got the cue from a service truck operator who's jumper
cables were obviously ROBUST. In subsequent years and
repeats of the jumper-cable fabrication task, I deduced
that the AAA Truck was rigged for worst case situations
involving vehicles a lot larger than aunt Minnie's
Dodge Dart. A little sharp pencil work deduced that
for us little guys, 4AWG offers adequate performance
with some left over.
Suggest you can re-size your deliberations about
space in your wiring conduits assuming the smaller
wire.
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: elec. noise in antennas |
On Oct 19, 2013, at 7:03 AM, Robert L. Nuckolls, III wrote:
>
> Understand. Recall that the Z-Figures are ARCHITECTURE drawings
> and that wire gauge callouts need to be validated against
> the real needs of your proposed system. Let's do a little
> sharp pencil work with your FAT wires:
>
> 4AWG wire has a resistance of 300 micro-ohms per foot. Your
> FAT wire engine cranking loop is 24 feet log.
Bob,
Yes...being an architect, I do keep in mind that your Z-xx diagrams are
conceptual frameworks subject to computation for sizing.
I humbly bow...no joke...to the knowledge and experience embedded in
your "sharp pencil work"...case in point...while I'm aware of the fact
that calculating resistance in the length of wire is a critical factor
when sizing wires, I would not have used the "loop" dimension...rather,
I would have used the distance from battery to starter. :-((
A question:
In your "sharp pencil work", you used 200 amps as a load for
cranking..I'm astonished that the load could be so high...even on a cold
morning. At the moment, I'm seeking the rating of my starter motor, and
have been anticipating to use that rating to determine the max. current
flow in order to size the wire to it.
Is that not the way to do it?
Fred
________________________________________________________________________________
| From: | Jeff Luckey <jluckey(at)pacbell.net> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
=0AHere we go into a deep dive:=0A=0A"I believe its better not to twist the
=0A wires before insertion into a crimp terminal. Better gas tight=0A
crimp."=0A=0ATwisting the conductors of a fresh strip probably has lit
tle effect on the "gas tightness" of the joint in a properly-crimped wire t
erminal.=C2- Getting all of the strands of the conductor into the termina
l is the goal and twisting can really facilitate this.=C2- Also, when usi
ng certain types of splicing terminal like: =0A=0A=0Ahttp://tinyurl.com/lsv
jhfy=0A=0Ait is standard practice to twist all conductors together then cri
mp the cap in place.=0A=0ANow, going deeper, the type of wire has a lot to
do with it.=C2- When working w/ high-quality aviation wire, twisting is u
sually not necessary because if you look carefully at the end of a freshly
stripped piece of MIL-W-22759 ("Tefzel") wire, it is already twisted and th
e strands tend to lie together quite nicely.=C2- =0A=0A=0Ahttp://tinyurl.
com/kqssbro=0A=0AThis is not the case w/ other types of wire - strip a piec
e of zipcord & you'll see what I mean.=0A=0ANow, it is possible that contam
inants from fingertips could be left behind on the conductor and that's pro
bably not the best thing.=C2- (When I'm doing electrical work, I try to k
eep my hands as clean as possible)=C2- I've made a whole bunch of termina
tions over the decades and I'm unaware of any problems caused by this pract
ice.=0A=0A=0A=0A"...I find that it holds onto the insulated part and then t
he =9Cclaws=9D then ruin the copper strands by squashing them.
"=0A=0AI just stripped a piece of wire w/ my Klein "Katapult" and technique
has a lot to do with it.=C2- I notice thatI pull the wire out of the cla
mping jaws as soon as it will come free by keeping tension on the wire as I
(slowly) release the tool after stripping.=C2- This pulls the wire clear
of the tool before the stripping dies have a chance to snap back and whack
the newly-stripped end.=0A=0AHere are a couple of tips:=0A1. Squeeze the t
ool fully, until it stops when performing the strip.=C2- This sets whatev
er sequencing mechanism in the tool.=0A2. Release the tool slowly (keeping
tension on the wire, as mentioned above) - duration of the release should b
e around a second.=0A3. Do some "dry runs" and watch when the wire clamping
jaws begin to move on release.=C2- If you play w/ it, you will notice th
at when operating the tool quickly, sometimes the wire-clamping jaws do not
release before the heads slap back together, hence the suggestion to slow-
down the release.=0A=0AYMMV (WTMI)=0A=0A=0A=0A-Jeff=0A=0A=0A=0A=0A_________
_______________________=0A From: John W Livingston <livingjw(at)earthlink.net>
=0ATo: aeroelectric-list(at)matronics.com =0ASent: Friday, October 18, 2013 11
:19 AM=0ASubject: Re: AeroElectric-List: Re: EAA SPORTAIR Workshop attendee
has question=0A =0A=0A=0AI believe its better not to twist the wires befor
e insertion into a crimp terminal. Better gas tight crimp.=0A=0AJWL=0A=0A
=0AOn 10/18/2013 1:39 PM, Jeff Luckey wrote:=0A=0A=0A>=0A>I've not had that
problem, but the suggestion below is probably a good one.=C2- Also, I al
ways give the strands of a freshly stripped end a good twisting - it makes
insertion into the wire terminal easier.=C2- I'm not aware of any setting
s or adjustments on the tool that would help.=0A>=0A>=0A>=0A>-J=0A>=0A>=0A>
________________________________=0A> From: Dave Saylor <dave.saylor.aircraf
ters(at)gmail.com>=0A>To: "aeroelectric-list(at)matronics.com" @matronics.com> =0A>Sent: Friday, October 18, 2013 7:21 AM=0A>Subject: Re:
AeroElectric-List: Re: EAA SPORTAIR Workshop attendee has question=0A> =0A>
=0A>=0A>I know exactly the problem you're describing. I think you'll find t
hat if you=C2-just=C2-release the handles a little more slowly that the
grip=C2-will release the wire before the blades can smack the freshly st
ripped section.=C2- =0A>Hi Jeff,=0A>>I bought the same tool a few months
ago.=C2- But I am reluctant to use it because I have difficulty in using
it properly: it strips the insulation off the wire fine, but when I open th
e handles to release the wire, I find that it holds onto the insulated part
and then the =9Cclaws=9D then ruin the copper strands by squas
hing them. =C2-Its nothing major, but then I have to go and twist the str
ands together again by hand.=0A>>Do you have the same problem? Is there a w
ay to set it so it doesn=99t do that?=0A>>Sac=0A>>_ =0A>=0A>-- =0A>--
=
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Sizing the wires |
>
>A question:
>
>In your "sharp pencil work", you used 200 amps as a load for
>cranking..I'm astonished that the load could be so high...even on a
>cold morning. At the moment, I'm seeking the rating of my starter
>motor, and have been anticipating to use that rating to determine
>the max. current flow in order to size the wire to it.
>
>Is that not the way to do it?
In the best of all worlds, you bet. But like the
quest for OPERATING numbers for electro-whizzies
on your engine, the manufacturers of those devices
are generally ignorant of operating conditions.
The 'ratings' on the box or data sheets usually
speak to limits. "Operate my gizmo at or below these
numbers and you may expect it to perform as I have
otherwise detailed in this data sheet . . . and do
it for a long time."
So a rating on your starter motor will probably
speak to some torque-RPM curve at some voltage . . .
or perhaps a family of voltages. It will also
set a limit on temperature rise. The wizard
Charles Kettering first demonstrated how you
can flog a 1 hp motor to 5 hp of output . . .
as long as you don't expect it perform for
more than a few seconds with plenty of time
to cool off between cycles.
Someplace in that array of torque-rpm vs. voltage
curves exists an envelope of demands that your
engine may place on the motor. The system
integrator that selected the motor looked at
the data, purchasing looked at the price
and between them decided to try it. It "did
the job" but it's almost a given that nobody
plotted the full family of starter demands based
on battery condition from new to soggy, plugs
from new to perhaps past recommended life, temperature,
mixtures and fuel flows all over the charts,
oil, etc. etc.
To be sure, if you plot likelihood of extremes
for those combinations, you'll get a kind of
bell shaped curve for severity of demand where
the vast majority of starts are well inside the
motor's design limits and the engine starts in
one or two blades. But the point to be made here
is that there is little or no connection between
'ratings' on your starter motor and how the
system is going to perform.
I've got a high speed data acquisition system
that I'm planning to apply to the fleet of
vehicles in my drive to get some energy demands
in real life situations. Maybe I can get that
set up before the next -10F overnight temps
hit this winter.
Given that we have no "real" numbers for your
airplane, the next best data for doing the
sharp pencil work is to assume a worst case.
Yeah, that number should be astonishing
and it's probably for come condition that
lies out at the worst case limits on the bell
curve. If we could PROVE that those limits
are un-realistically large, cool. But we
have to move forward with what we have and
strive to refine it as we go.
I've often theorized about the possibility of
doing a "Watt-Second Study" on a constellation
of flying hardware. Maybe at a series of fly-ins.
Of course, those always tend to be fair-weather
events. I'd still need to get data somewhat
displaced from the center of the bell curve.
It would be nice to have such data to relieve
the task of sizing components or predicting
performance with numbers no better than throwing
darts at a data sheet.
Having an engine that is artfully managed with
electronics is a BIG plus for a battery.
Artful software automatically accounts for many
variables in the cranking mode. Yeah, all those
byte thrashers may give you a bit better fuel
consumption but it also offers an opportunity
for getting 5+ years out of a battery.
A Beech Skipper I used to rent was pretty easy
to figure out the combination of pre-flight
prop swing, throttle setting and seconds of
primer needed to light it off very quickly.
But I recall more than one neophyte pilot flogging
that airplane's battery and starter to near
exhaustion/destruction because they had not
acquired that man-machine connection that makes
life so much simpler.
So add another variable to the constellation
of influences on starter performance . . . pilot
skills.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Relay for Critical Power Feed |
At 02:24 AM 10/15/2013, you wrote:
>Following up on automotive relays.
>Eric
>
Good data sir! Thank you.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Relay for Critical Power Feed |
Relays sat stationary on the bench during tests. Vibration in
real-world use would almost certainly alter these results just bit.
Next I did a very unscientific check of holding force. I crimped
PIDG fast-on connectors to two wires and connected them to the
normally open relay contacts. I fed 5V from a power supply, through
a 100k resistor, through these wires, with an oscilloscope probe
attached across the resistor. I set the relay coil voltage from
another power supply at 14.0V, so that the relay closed and the scope
displayed a constant 5V DC. I set the scope to trigger on a falling
slope at 4.7V. I then slapped the relay against the bench top in
every direction except pins-down, until the contacts bounced. A
typical bounce waveform is attached. I have no idea how many g it
took to bounce the contacts, but it was a pretty solid
smack. Certainly much more severe than any turbulence I care to encounter!
Eric
I delayed joining this thread because I recalled
a conversation we had here on the List some time
back about contactors opening up under vibration . . .
actually shock.
That conversation spooled up after a builder posted
a note stating that while working on his
airplane, battery-only, he dropped a tool on his
battery contactor and the EFIS rebooted. He repeated
the experiment several times and then came to the
List to inquire into the suitability of this device
to its intended task.
Of course, many tens of thousands of this style
contactor had been used as battery master control
on light airplanes for close to a century. Several
companies offered similar products but most notably,
White-Rodgers/Stancore and Cole-Hersee. The builder's
problem presented in a Cole-Hersee part he had
purchased from Van's.
I had an exemplar C-H part which I set up on the bench
not unlike Eric's experiment above. I was astounded to discover
that what I thought was a relatively light tap with a
box-wrench caused a demonstrable discontinuity in the
contactor's conductivity.
Hmmmm . . . bad contactor? I was selling W-R/S contactors
at the time so I put one of those on the same test set up
and guess what? It did it too.
"Holy contacts Batman, how can this be?"
After some thought I came to two understandings about
the nature of this phenomenon. First, striking the steel
enclosure of the contactor with a steel tool was a
shock force. In terms of g-levels it could have easily
reached the big numbers. Certainly 10Gs and 100G would
not have surprised me.
Second, why did this not manifest before? Answer, it HAD,
many, many times over the decades. But all of the
applications that made these contactors popular DID NOT
feature solid state electronics . . . particularly
fitted with microprocessors that would re-set on
microsecond notice.
Then the lights came on. At some time toward the end
of my tenure in the sales of contactors, W-R/S modified
their 70 series devices to add plastic booties over
the mounting feet.
Emacs!
I wrote to W-R/C and called a rep to see if I could
get an explanation for why those 'insulators' were
added to the mounting. Never got a satisfactory
answer . . . in fact never got any answer.
But I'll be you $5 to your donut (used to be
a dollar . . . but you know . . . inflation),
that some new electric vehicle with modern,
CPU driven controls demonstrated the same phenomenon
reported by our brother builder in his
airplane. The good folks at W-R/S couldn't do a thing
about failure of some manufacturer to do DO-160
style qualification to his fork lift controller
. . . the next best thing was to modify the contactor
for better resistance to hi-G pulses or shock.
Of course, hitting the contactor with a wrench
continues to produce the same demonstrable dis-
continuity. The difference being that the same
shocks delivered through the mounting feet are less
likely to interrupt the flow of power through
the contactor.
What's the likelihood of delivering such 10+
G shock to the contactor in your airplane?
VERY low, hence the exemplar service life of
this device in airplanes . . . even machines
fitted with electronics having twitchy reset
characteristics.
Nonetheless, the discovery was a surprise. At the
time I was engaged in some relay life issues at
Hawker-Beech and this discovery on the contactors
prompted some explorations into smaller relays . . .
particularly some mil-spec devices. Guess what?
They do it too.
I couldn't find the data plots I took on the contactor
experiments. If I run across them in the future, I'll
re-post this note alone with the data. I don't
think I recorded any data on the $high$ relays,
those investigations were never formally reported.
Bottom line is that shock . . . fast rise, short duration
high intensity transients are a special kind of
vibration that gets spec'ed separately from the
shake, rattle and roll of the airframe. This further
emphasizes the need for good practice in the design
of input power conditioning for particularly
vulnerable avionics. Design practice that should
happen INSIDE the box at the factory . . . not
outside the box at the airplane.
So the short answer to the topic question of this
thread is, yes . . . plain vanilla contactors
and relays are just as suited to control "critical"
power as they ever were. The companion question is
whether or not the designers of potentially vulnerable
systems understood and considered the wild-and-wooly
nature of DC power systems in all manner of vehicle.
I have referred numerous non-aviation clients to
DO-160 as a set of exemplar guidelines for successful
marketing of a new product.
Bob . . .
________________________________________________________________________________
| From: | JOHN TIPTON <jmtipton(at)btopenworld.com> |
| Subject: | Re: EAA SPORTAIR Workshop attendee has question |
What isn't noticed by the majority is that the strands are twisted anti clo
ckwise, so the majority who cannot resist twisting, actually 'un-twist' the
starnds=0A=0A=0A=0A>________________________________=0A> From: Jeff Luckey
=0A>To: "aeroelectric-list(at)matronics.com" =0A>Sent: Saturday, 19 October 2013, 17:43=0A>Subjec
t: Re: AeroElectric-List: Re: EAA SPORTAIR Workshop attendee has question
=0A> =0A>=0A>=0A>=0A>Here we go into a deep dive:=0A>=0A>"I believe its bet
ter not to twist the=0A wires before insertion into a crimp terminal.
Better gas tight=0A crimp."=0A>=0A>Twisting the conductors of a fresh
strip probably has little effect on the "gas tightness" of the joint in a p
roperly-crimped wire terminal.=C2- Getting all of the strands of the cond
uctor into the terminal is the goal and twisting can really facilitate this
.=C2- Also, when using certain types of splicing terminal like: =0A>=0A>
=0A>http://tinyurl.com/lsvjhfy=0A>=0A>it is standard practice to twist all
conductors together then crimp the cap in place.=0A>=0A>Now, going deeper,
the type of wire has a lot to do with it.=C2- When working w/ high-qualit
y aviation wire, twisting is usually not necessary because if you look care
fully at the end of a freshly stripped piece of MIL-W-22759 ("Tefzel") wire
, it is already twisted and the strands tend to lie together quite nicely.
=C2- =0A>=0A>=0A>http://tinyurl.com/kqssbro=0A>=0A>This is not the case w
/ other types of wire - strip a piece of zipcord & you'll see what I mean.
=0A>=0A>Now, it is possible that contaminants from fingertips could be left
behind on the conductor and that's probably not the best thing.=C2- (Whe
n I'm doing electrical work, I try to keep my hands as clean as possible)
=C2- I've made a whole bunch of terminations over the decades and I'm una
ware of any problems caused by this practice.=0A>=0A>=0A>=0A>"...I find tha
t it holds onto the insulated part and then the =9Cclaws=9D the
n ruin the copper strands by squashing them. "=0A>=0A>I just stripped a pie
ce of wire w/ my Klein "Katapult" and technique has a lot to do with it.=C2
- I notice that I pull the wire out of the clamping jaws as soon as it wi
ll come free by keeping tension on the wire as I (slowly) release the tool
after stripping.=C2- This pulls the wire clear of the tool before the str
ipping dies have a chance to snap back and whack the newly-stripped end.
=0A>=0A>Here are a couple of tips:=0A>1. Squeeze the tool fully, until it s
tops when performing the strip.=C2- This sets whatever sequencing mechani
sm in the tool.=0A>2. Release the tool slowly (keeping tension on the wire,
as mentioned above) - duration of the release should be around a second.
=0A>3. Do some "dry runs" and watch when the wire clamping jaws begin to mo
ve on release.=C2- If you play w/ it, you will notice that when operating
the tool quickly, sometimes the wire-clamping jaws do=0A not release befor
e the heads slap back together, hence the suggestion to slow-down the relea
se.=0A>=0A>YMMV (WTMI)=0A>=0A>=0A>=0A>=0A>=0A>-Jeff=0A>=0A>=0A>=0A>=0A>=0A>
=0A>________________________________=0A> From: John W Livingston <livingjw@
earthlink.net>=0A>To: aeroelectric-list(at)matronics.com =0A>Sent: Friday, Oct
ober 18, 2013 11:19 AM=0A>Subject: Re: AeroElectric-List: Re: EAA SPORTAIR
Workshop attendee has question=0A> =0A>=0A>=0A>I believe its better not to
twist the wires before insertion into a crimp terminal. Better gas tight cr
imp.=0A>=0A>JWL=0A>=0A>=0A>On 10/18/2013 1:39 PM, Jeff Luckey wrote:=0A>=0A
>=0A>>=0A>>I've not had that problem, but the suggestion below is probably
a good one.=C2- Also, I always give the strands of a freshly stripped end
a good twisting - it makes insertion into the wire terminal easier.=C2-
I'm not aware of any settings or adjustments on the tool that would help.
=0A>>=0A>>=0A>>=0A>>-J=0A>>=0A>>=0A>>________________________________=0A>>
From: Dave Saylor <dave.saylor.aircrafters(at)gmail.com>=0A>>To: "aeroelectric
-list(at)matronics.com" =0A>>Sent: Friday, O
ctober 18, 2013 7:21 AM=0A>>Subject: Re: AeroElectric-List: Re: EAA SPORTAI
R Workshop attendee has question=0A>> =0A>>=0A>>=0A>>I know exactly the pro
blem you're describing. I think you'll find that if you=C2-just=C2-rele
ase the handles a little more slowly that the grip=C2-will release the wi
re before the blades can smack the freshly stripped section.=C2- =0A>>Hi
Jeff,=0A>>>I bought the same tool a few months ago.=C2- But I am reluctan
t to use it because I have difficulty in using it properly: it strips the i
nsulation off the wire fine, but when I open the handles to release the wir
e, I find that it holds onto the insulated part and then the =9Cclaws
=9D then ruin the copper strands by squashing them. =C2-Its nothing
major, but then I have to go and twist the strands together again by hand.
=0A>>>Do you have the same problem? Is there a way to set it so it doesn
=99t do that?=0A>>>Sac=0A>>>_ =0A>>=0A>>-- =0A>>--Dave Saylor=0A>>=0A>
=0A>=======================
===================== =0A>=0A>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | To twist . . . or not to twist . . . |
At Hawker-Beech we had automated wire cutting, marking,
stripping and termination machines that produced thousands
of ready-to-install wire segments a day. None of these machines
had a 'twisting' function. The as-stripped strands were
immediately fitted with the appropriate terminal and
crimped.
A review of NASA-STD-8739.4 for the fabrication of wire
bundles and terminations, I found no example for terminating
wires were either single or multiple wires were twisted
by the installer before attaching a terminal.
Emacs!
I've never witnessed such a practice by technicians nor am I aware
of a rationale for doing so.
In fact, the 'wire nut' designed for wiring of buildings
achieves gas tight connections at the corners of a square-
wire, conical-spring. As the device is twisted
over the ends of parallel strands, the cone expands and
crawls up and over the ends of the cut strands.
An early example of this technology was not insulated.
Emacs!
A conical spring wound of round wire and fitted
with a 'handle' was simply wound onto parallel
strands. The counter-wind torque expanded the
spring up and over the strands thus increasing
the pressure that kept the wires in good contact.
Later versions deleted the handle, added insulating
cap that also served as a handle . . .
Emacs!
They also wound the spring with square wire having
a corner turned in. This sharp edge would bite into
the strands of wire thus increasing both mechanical
grip for running the spring onto the strands AND
increasing the numbers of high-pressure (gas tight)
joints between conducting elements of the connection.
None of these products would benefit from a pre-twisting
of the wires before installation. Standard practice calls
for twisting the cap on until the strands DO twist slightly,
say 1/2 turn or so. This is your installation limit indicator
that the spring is no longer climbing onto the wires and
further rotation serves only to twist the bundle which
adds nothing to the quality of the finished joint.
Therefore, the short answer for any kind of installer-
twisting of strands in a wire or wires in a bundle
seems to be "not necessary and possibly deleterious
to the finished joint."
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | To twist . . . or not to twist . . . IMAGES CORRECTED |
At Hawker-Beech we had automated wire cutting, marking,
stripping and termination machines that produced thousands
of ready-to-install wire segments a day. None of these machines
had a 'twisting' function. The as-stripped strands were
immediately fitted with the appropriate terminal and
crimped.
A review of NASA-STD-8739.4 for the fabrication of wire
bundles and terminations, I found no example for terminating
wires were either single or multiple wires were twisted
by the installer before attaching a terminal.
Emacs!
I've never witnessed such a practice by technicians nor am I aware
of a rationale for doing so.
In fact, the 'wire nut' designed for wiring of buildings
achieves gas tight connections at the corners of a square-
wire, conical-spring. As the device is twisted
over the ends of parallel strands, the cone expands and
crawls up and over the ends of the cut strands.
An early example of this technology was not insulated.
Emacs!
A conical spring wound of round wire and fitted
with a 'handle' was simply wound onto parallel
strands. The counter-wind torque expanded the
spring up and over the strands thus increasing
the pressure that kept the wires in good contact.
Later versions deleted the handle, added insulating
cap that also served as a handle . . .
Emacs!
They also wound the spring with square wire having
a corner turned in. This sharp edge would bite into
the strands of wire thus increasing both mechanical
grip for running the spring onto the strands AND
increasing the numbers of high-pressure (gas tight)
joints between conducting elements of the connection.
None of these products would benefit from a pre-twisting
of the wires before installation. Standard practice calls
for twisting the cap on until the strands DO twist slightly,
say 1/2 turn or so. This is your installation limit indicator
that the spring is no longer climbing onto the wires and
further rotation serves only to twist the bundle which
adds nothing to the quality of the finished joint.
Therefore, the short answer for any kind of installer-
twisting of strands in a wire or wires in a bundle
seems to be "not necessary and possibly deleterious
to the finished joint."
Bob . . .
________________________________________________________________________________
| Subject: | Re: To twist . . . or not to twist . . . |
| From: | Robert Reed <RobertR237(at)att.net> |
The only exception I can point out would be if anything should cause stray s
trands to separate from the bundle.
Bob Reed
Sent from my iPhone
> On Oct 19, 2013, at 5:56 PM, "Robert L. Nuckolls, III" <nuckolls.bob@aeroe
lectric.com> wrote:
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 04:01 PM 10/14/2013, you wrote:
>On Oct 14, 2013, at 12:16 PM, Ken wrote:
>
>>You are in the ballpark Fred but it's probably safe to round down
>>to 20 amps for a no alternator battery life calculation.
>
>Ken...thank you for your "3rd party validation"...at this stage of
>the game, I'd rather be conservative, and I'm looking forward to
>Bob's assessment.
I think I'm down to the last missing data point.
How do you switch between ECU modules? Do you have
a wiring diagram of this feature you can sketch or scan
to share?
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 19, 2013, at 6:09 PM, Robert L. Nuckolls, III wrote:
>
> At 04:01 PM 10/14/2013, you wrote:
>
>> On Oct 14, 2013, at 12:16 PM, Ken wrote:
>>
>>> You are in the ballpark Fred but it's probably safe to round down to
20 amps for a no alternator battery life calculation.
>>
>> Ken...thank you for your "3rd party validation"...at this stage of
the game, I'd rather be conservative, and I'm looking forward to Bob's
assessment.
>
> I think I'm down to the last missing data point.
>
> How do you switch between ECU modules? Do you have
> a wiring diagram of this feature you can sketch or scan
> to share?
>
>
>
> Bob . . .
Bob...the guts of the ECU is in a box mounted on the cockpit side of the
firewall...is is connected to a small control console mounted on the
panel via a D Sub cable. This small control panel includes a switch
which toggles between the "A" motherboard and its back up, the "B"
motherboard. In the D Sub connector, there are separate power inputs for
A and B. I have no wiring diagram explaining this feature. Here is a
photo of the panel mounted control console...the toggle switch obscures
the "A".
Check it out in the lower right of the panel...then view close up:
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
>Check it out in the lower right of the panel...then view close up:\
I guess I missed that in the original set of
photos. Do these separate inputs need to be
switched . . . or is ECU power control accomplished
from the little panel?
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 19, 2013, at 8:54 PM, Robert L. Nuckolls, III wrote:
>> Check it out in the lower right of the panel...then view close up:\
>
> I guess I missed that in the original set of
> photos. Do these separate inputs need to be
> switched . . . or is ECU power control accomplished
> from the little panel?
We will need a switch or circuit breaker between the
battery and the ECU...ditto for the fuel injectors, coils, and fuel
pumps.
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | EXP Bus workaround |
Bob...I'm not sure what you're up to, but I have been looking at the implications
of some variations under these givens; namely, that:
- Batteries aft, wired together...act as one battery
- Bat Contactors aft...ALL buses forward on either side of firewall to be determined
- EXBus serves as Main Power Distribution Bus
- Endurance Bus has alternate feed from Engine Bus
ALTERNATIVE # 2
- EXP Master Switch fed thru Contactor #1
- Starter fed from Contactor #1 and EXP Bus
- Engine Bus fed thru Contactor #2
CRITICAL IMPLICATIONS:
- If Master switch is OFF, starter cannot be energized
- If Contactor #2 fails, engine will not run
- If Bat #2 switch is turned OFF unintentionally, engine will NOT run
- Long feeder from aft contactor to Engine Bus is NOT always hot and is protected
by contactor
ALTERNATIVE # 3
- EXP Master Switch fed thru Contactor #1
- Starter fed from Contactor #2 and Engine Bus
- Engine Bus fed thru Contactor #2
CRITICAL IMPLICATIONS:
- If Master Switch is OFF, starter can still be energized thru Contactor #2
- If Contactor #2 fails, engine will not run
- If Bat #2 switch is turned OFF unintentially, engine will NOT run
- Long feeder from aft contactor to Engine Bus is NOT always hot and is protected
by contactor
ALTERNATIVE #4
- EXP Master Switch fed thru Contactor #1
- Starter fed from Contactor #2
- Engine Bus fed direct from Battery
CRITICAL IMPLICATIONS:
- If Master Switch is OFF, starter can still be energized thru Contactor #2
- If Contactor #2 fails engine will continue to run
- If Bat #2 switch is turned OFF unintentionally, engine will continue to run
- Long feeder from aft (Battery side of) contactor #2 is ALWAYS HOT and unprotected
by CB or fuse
I'm just tryin to eat the elephant one bite at a time...in doing so, I tend to
favor Alternative #4 if risk of ALWAYS HOT feed to engine bus is sufficiently
mitigated w/ a non-conductive airframe and possibly other considerations.
Fred
________________________________________________________________________________
| Subject: | Re: Relay for Critical Power Feed |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
Don't use Type-70 Stancore-White-Rodgers-Emerson-Tyco contactors in your aircraft.
The reasons are plentiful: They have a 122 deg F maximum ambient. They are
not water or fuel proof, they won't open against high currents or voltages. They
are position sensitive and have low G-withstands. Disregard the fact that
they have been used and failing for many years. There are better ways to go. Bob
N. and I have argued this for years. Here are some excerpts from the archives:
--Relay mounting. Type 70 Stancor Rodgers White Emerson Tyco. See:
http://www.alliedelec.com/Images/Products/Datasheets/BM/STANCOR/Stancor_Industrial-Control_5760005.pdf
So the manufacturer says, "mount plunger vertical, cap down". I checked
into the engineering data on this part and of course the corporate
conglomeratization has destroyed the engineering knowledge that built the
part. The manufacturer PROMISED they'd get back to me.....BUT It's not DO-160 bubela.
And it's only 122 deg F max operating temp. Etc. etc.
I spent many hours tracking down the designers of this Stancor-White-Rogers Emerson
Tyco Type-70. The only info that remains available seems to be the present
specs. The available newly produced Type-70 specs simply make it unsuitable.
Will it work, Yes. Will it fail? Yes, sooner than you'd like. It is entirely
possible that Cessna had a custom model. Is Cessna still using these? Possibly,
but certificated a/c tend to use old original technology until it bleeds. There's
no reason you should follow them.
The Kilovac Czonkas II's are made in many types. There is a marine model too that
is perfectly usable. (Blue Sea Systems p/n 9012) But I don't have stock in
Kilovac. There are many makers of newer stuff [Gigavac has come out with similar
contactors].
For my airplane, I'll use a Flaming River Battery switch if I can, and an EV200
otherwise....
ps: Guess how Kilovac and Gigavac clamp coil voltages generated from the collapsing
magnetic field? That's right...internal bidirectional zeners.
"Everything you've learned in school as "obvious" becomes less and less
obvious as you begin to study the universe. For example, there are no
solids in the universe. There's not even a suggestion of a solid. There
are no absolute continuums. There are no surfaces. There are no straight
lines."
- R. Buckminster Fuller
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410914#410914
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Relay for Critical Power Feed |
At 08:18 AM 10/20/2013, you wrote:
>
>Don't use Type-70 Stancore-White-Rodgers-Emerson-Tyco contactors in
>your aircraft. The reasons are plentiful: They have a 122 deg F
>maximum ambient. They are not water or fuel proof, they won't open
>against high currents or voltages. They are position sensitive and
>have low G-withstands. Disregard the fact that they have been used
>and failing for many years. There are better ways to go. Bob N. and
>I have argued this for years. Here are some excerpts from the archives:
"Better" is non quantitative. Just a few weeks ago
I received a failed, 70-series contactor removed from
a 70's model Cessna. The owner believed that it was
the original contactor. We did a tear down and discovered
that indeed, the contacts had become intermittent due
to corrosion on contacts exacerbated by ingress of moisture.
Mechanically the device was intact and functional . . .
after 30+ years of service.
Emacs!
Here's the mating set of contacts . . .
Emacs!
For a device that has been operated for 30+ years
"outside the spec sheet" envelope of limits it looks
pretty good to me. Would this Cessna owner be well
advised to install something "better"?
If "better" means that some other device will not succumb
to moisture (sealed contact chamber) and it has higher
ambient temperature ratings, then yes, this carry-over from
the 1940's has some peers with improvements that have
evolved over time . . . often crafted to meet the needs
of a more antagonistic environment.
But when cherry-picking of features that are "better"
becomes a driving force in our decision making processes,
then other authors on this List could opine that one
should avoid the IO-360 in favor of some newer
technology. Or perhaps we are well advised to abandon
panel mounted switches . . .
We gave up these switches
Emacs!
in favor of these . . .
Emacs!
For reasons that are fairly obvious. But consider
the constellation of simple-ideas that come with
the use of this part in your airplane:
Emacs!
There are 10 new metallic joints added to every
current carrying path by the use of these switches.
That's a fist-full of new opportunities for failure.
But each opportunity for failure is exploited by
environmental conditions and craftsmanship of the
installer.
These switches HAVE suffered some interesting
failures . . .
Emacs!
Question: Have switches of this genre ever bubbled
to the surface as a hazard so egregious as to generate
an AD against hundreds of thousands of such devices
flying for the past 70 years?
This switch has suffered that dubiou honor . . .
Emacs!
Every owner of a Baron or Bonanza has a new item
on his/her worry-list due to an un-foreseen deficiency
in the design . . . a deficiency that took decades
of field service before it bubbled up and people-paid-
to-worry took notice.
Even people-paid-to-worry have not banned the humble
ol' workhorse that is the 70-series contactor from
flying aboard airplanes. We can sing the ballad of
dueling specsheets but the bottom line is that this
product has a SERVICE HISTORY that demonstrates it
to be good value. I.e. performance traded against
cost of ownership while being attentive to
increased risks.
Since we're ALL building failure tolerant electrical
systems I can confidently suggest that consideration
of "better" contactors is driven more by our desire to
own and drive a Benz as opposed to a Ford . . . in spite
of the fact that both vehicles have high order
probability of getting us from point A to point B over
15 years and 200,000 miles at low risk . . . but with
markedly different costs of ownership.
Everything Eric has offered is true. The point of
this discussion . . . indeed the point of this List
is to sift the simple-ideas of any recipe for success
and make decisions based on cost of ownership weighed
against risk while sprinkling in some personal
preferences for V-Power or EXP-Bus in with the gaggle
of fuses and toggle switches. Just as S-K vs.
Harbor Freight tools are judged in the marketplace,
the value of a recipe-for success in our airplanes is
demonstrated in the air.
It's not WHAT we choose to use but the UNDERSTANDING
we bring to airplane to keep OPERABILITY high, RISKS
low while fitting COST of ownership to our own bank
accounts. The 70-series contactor has demonstrated
itself not to be a black hat lurking behind a rock
awaiting the opportunity to give you a bad day in the
cockpit. In 50 years of hammering on airplanes I can
confidently assert that the greatest risks for failure
to perform are human factors issues of installation,
maintenance or operation. Failure to perform based
inattention to specifications is VERY low on the list
things cause pilots to break a sweat while airborne.
Failure tolerant design strives to make any failure
a MAINTENANCE and COST OF OWNERSHIP issue as opposed
to a reason for breaking a sweat.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Relay for Critical Power Feed |
>
>I spent many hours tracking down the designers of this
>Stancor-White-Rogers Emerson Tyco Type-70.
Those guys died years ago . . .
> The only info that remains available seems to be the present
> specs. The available newly produced Type-70 specs simply make it
> unsuitable. Will it work, Yes. Will it fail? Yes, sooner than you'd like.
Quantify "sooner" and "like" . . . and lay foundation
for those numbers.
>It is entirely possible that Cessna had a custom model.
They did not. Everything Cessna purchased in those
days were catalog items folded into the qualified
parts stream by virtue of words and illustrations
on a piece of paper (we called them C-Drawings).
Beech did the same thing on the W-31 breaker-switches.
I did the same thing at Electro-Mech.
But when C-H was selling thousands per year to
Beech and Cessna versus hundreds of thousands per
year to customers unwashed by the FARS, who do you think
drove design decisions?
>Is Cessna still using these?
I'll have access to Cessna's great data-base-in-the-sky
in a few weeks. I'll see what is being offered as spares
for a 1970 C-172.
>Possibly, but certificated a/c tend to use old original technology
>until it bleeds.
Does the IO-360 bleed? Has the lead-acid
battery been relegated to the pages of
aviation history? Has the incandescent
landing light been pried out and replaced
with LED as a hazard to the airframe and
occupants?
>ps: Guess how Kilovac and Gigavac clamp coil voltages generated from
>the collapsing
>magnetic field? That's right...internal bidirectional zeners.
We explored the value of Benz versus Ford style
coil suppression about 13 years ago. I went to the
bench and did qualitative and quantitative measurements
on the differences in performance and benefits derived
therefrom. Did you find errors in either my process,
measurement or reasoning?
http://tinyurl.com/nva2xdy
http://tinyurl.com/25wjo7w
http://tinyurl.com/jwxxav8
Bob . . .
________________________________________________________________________________
| Subject: | Re: Relay for Critical Power Feed |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
Your photo of the 30 year old contactor discloses: 30 years ago they looked like
they were built better. The one you show is not the same one that is being used
now.
I stand my ground: Published specification for the Type-70 contactor say not to
use it in the applications for which it is being used. Regardless of the fact
that one can get away with it, better solutions are at hand.
> Does the IO-360 bleed? Has the lead-acid battery been relegated to the pages
of aviation history? Has the incandescent landing light been pried out and replaced
with LED as a hazard to the airframe and occupants?
>
Strawman arguments Bob. You can do better.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410920#410920
________________________________________________________________________________
| Subject: | Re: Relay for Critical Power Feed |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
Attached disassembled Type-70 (minus cap).
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410921#410921
Attachments:
http://forums.matronics.com//files/type_70_411.jpg
________________________________________________________________________________
| Subject: | Re: Relay for Critical Power Feed |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
Attached disassembled Type-70 (minus cap and copper coil). A long cost-cutting
way down from the part you show.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=410923#410923
Attachments:
http://forums.matronics.com//files/type_70_119.jpg
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Relay for Critical Power Feed |
Been having some problems with cut-n-paste between PhotoShop
and my email client . . . the email client doesn't always
keep the ducks lined up. The workaround seems to be to save
the image to hard drive and then import to the email client as
a file . . .
Reposted with corrected images . . .
At 08:18 AM 10/20/2013, you wrote:
>
>Don't use Type-70 Stancore-White-Rodgers-Emerson-Tyco contactors in
>your aircraft. The reasons are plentiful: They have a 122 deg F
>maximum ambient. They are not water or fuel proof, they won't open
>against high currents or voltages. They are position sensitive and
>have low G-withstands. Disregard the fact that they have been used
>and failing for many years. There are better ways to go. Bob N. and
>I have argued this for years. Here are some excerpts from the archives:
"Better" is non quantitative. Just a few weeks ago
I received a failed, 70-series contactor removed from
a 70's model Cessna. The owner believed that it was
the original contactor. We did a tear down and discovered
that indeed, the contacts had become intermittent due
to corrosion on contacts exacerbated by ingress of moisture.
Mechanically the device was intact and functional . . .
after 30+ years of service.
Emacs!
Here's the mating set of contacts . . .
Emacs!
For a device that has been operated for 30+ years
"outside the spec sheet" envelope of limits it looks
pretty good to me. Would this Cessna owner be well
advised to install something "better"?
If "better" means that some other device will not succumb
to moisture (sealed contact chamber) and it has higher
ambient temperature ratings, then yes, this carry-over from
the 1940's has some peers with improvements that have
evolved over time . . . often crafted to meet the needs
of a more antagonistic environment.
But when cherry-picking of features that are "better"
becomes a driving force in our decision making processes,
then other authors on this List could opine that one
should avoid the IO-360 in favor of some newer
technology. Or perhaps we are well advised to abandon
panel mounted switches . . .
We gave up these switches
Emacs!
in favor of these . . .
Emacs!
For reasons that are fairly obvious. But consider
the constellation of simple-ideas that come with
the use of this part in your airplane:
Emacs!
There are 10 new metallic joints added to every
current carrying path by the use of these switches.
That's a fist-full of new opportunities for failure.
But each opportunity for failure is exploited by
environmental conditions and craftsmanship of the
installer.
These switches HAVE suffered some interesting
failures . . .
Emacs!
Question: Have switches of this genre ever bubbled
to the surface as a hazard so egregious as to generate
an AD against hundreds of thousands of such devices
flying for the past 70 years?
This switch has suffered that dubiou honor . . .
Emacs!
Every owner of a Baron or Bonanza has a new item
on his/her worry-list due to an un-foreseen deficiency
in the design . . . a deficiency that took decades
of field service before it bubbled up and people-paid-
to-worry took notice.
Even people-paid-to-worry have not banned the humble
ol' workhorse that is the 70-series contactor from
flying aboard airplanes. We can sing the ballad of
dueling specsheets but the bottom line is that this
product has a SERVICE HISTORY that demonstrates it
to be good value. I.e. performance traded against
cost of ownership while being attentive to
increased risks.
Since we're ALL building failure tolerant electrical
systems I can confidently suggest that consideration
of "better" contactors is driven more by our desire to
own and drive a Benz as opposed to a Ford . . . in spite
of the fact that both vehicles have high order
probability of getting us from point A to point B over
15 years and 200,000 miles at low risk . . . but with
markedly different costs of ownership.
Everything Eric has offered is true. The point of
this discussion . . . indeed the point of this List
is to sift the simple-ideas of any recipe for success
and make decisions based on cost of ownership weighed
against risk while sprinkling in some personal
preferences for V-Power or EXP-Bus in with the gaggle
of fuses and toggle switches. Just as S-K vs.
Harbor Freight tools are judged in the marketplace,
the value of a recipe-for success in our airplanes is
demonstrated in the air.
It's not WHAT we choose to use but the UNDERSTANDING
we bring to airplane to keep OPERABILITY high, RISKS
low while fitting COST of ownership to our own bank
accounts. The 70-series contactor has demonstrated
itself not to be a black hat lurking behind a rock
awaiting the opportunity to give you a bad day in the
cockpit. In 50 years of hammering on airplanes I can
confidently assert that the greatest risks for failure
to perform are human factors issues of installation,
maintenance or operation. Failure to perform based
inattention to specifications is VERY low on the list
things cause pilots to break a sweat while airborne.
Failure tolerant design strives to make any failure
a MAINTENANCE and COST OF OWNERSHIP issue as opposed
to a reason for breaking a sweat.
Bob . . .
________________________________________________________________________________
| From: | Charles Deiterich <cffd66(at)yahoo.com> |
| Subject: | Jabiru 2200 voltage regulator |
I have Jabiru 2200 serial # 988 which has the 10 amp alternator.- I have
the circuit diagram of the Kabota regulator.- Is there a writeup on how t
he regulator works?- It appears to have a differential amplifier to sense
the bus voltage and the then compares it to the AC coming from the alterna
tor.- I just don't understand how the zener diode provides a reference wi
thout a resistor to control the current through the zener and also how the
AC wave is compared to the reference.- But then again I have always have
had problems with PNP circuits.=0AChuck D.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Relay for Critical Power Feed |
At 11:10 AM 10/20/2013, you wrote:
>
>Attached disassembled Type-70 (minus cap and copper coil). A long
>cost-cutting way down from the part you show.
Really?
Are we privy to the conversations that transpired
during the last 50 years worth of engineering/management/
manufacturing/marketing meetings wherein the design
features of this product like were decided?
I'll invite our readers to review the library of
70 series photos at http://tinyurl.com/kcc26jt
These photos only go back to about 1960 . . . it seems
likely that a 1940 tear-down would show yet other
differences.
I would guess that this product line has
enjoyed a host of cost-cutting changes. Advancements
in materials and automation are nearly always
responsible for reductions in cost and/or improvements
in meeting design goals.
But consider that of the trio of failure teardowns
illustrated in the library of pictures, 2 failures
were the result of assembly error . . . a human
factor I cited earlier today. The third failure
occurred at or beyond any practical expectations
for service life on the product . . . the thing
operated as designed and expired gracefully
(random intermittent). Further it was not a player
in the classic trio of conditions that precede
so many sad events in aviation and elsewhere.
You seem to use the phrase "cost cutting" as
an epithet. I have participated in dozens of
tasks where cost-cutting was a mission
imperative. However, in no instance was degradation
of service life or performance considered a
component of the acceptable solution. More often
than not, the upgrade reduced costs while improving
on the value of the product.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Relay for Critical Power Feed |
> > Does the IO-360 bleed? Has the lead-acid battery been relegated
> to the pages of aviation history? Has the incandescent landing
> light been pried out and replaced with LED as a hazard to the
> airframe and occupants?
>
>Strawman arguments Bob. You can do better.
Okay, strike that paragraph. What about the others?
Bob . . .
________________________________________________________________________________
| From: | Charles Deiterich <cffd66(at)yahoo.com> |
| Subject: | Jabiru 2200 voltage regulator again |
I have Jabiru 2200 serial # 988 which has the 10 amp alternator.- I have
the circuit diagram of the Kabota regulator.- Is there a writeup on how t
he regulator works?- It appears to have a differential amplifier to =0Ase
nse the bus voltage and the then compares it to the AC coming from the alte
rnator.- I just don't understand how the zener diode provides a =0Arefere
nce without a resistor to control the current through the zener =0Aand also
how the AC wave is compared to the reference.- But then again I have alw
ays have had problems with PNP circuits.=0AChuck D.=0A=0A=0AFurther study s
hows that Q1 and Q2 are to light a low voltage lite and are not part of a d
ifferential amplifier.- Q3 and Q4 are for the regulator.- My comment ab
out the current limit on the zener still stands.- circuit is from: http:/
/www.aeroelectric.com/Pictures/Schematics/PM_Regulator/Kubota_Schematic.jpg
=0A=0AChuck D.=0A
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: EXP 2 Bus workaround |
If this question was for Ken...
On my one off z14 architecture 4 cylinder soob, I run two ecu's all the
time, one off each little battery. Two sets of injectors. Whichever set
of injectors is fed +12 volts flows fuel. If both are on by mistake the
engine loses some power but continues to run but a bit rough. I'm happy
with two switches for this. I don't need or want one either/or switch
although initially I was thinking that two mechanically interconnected
switches might be OK.
Similar with ignition. Whichever set of DIS coils is fed +12 volts feeds
the single plugs through MSD and homemade (polarity issue) HV coil
joiners. Both can be left on indefinitely or for landing and take off
but I only use one at a time.
In steady state cruise 18amps runs my airplane. That includes running
the VHF radio, transponder, intercom, engine monitor, gps, and maybe an
amp (or less) to the battery. If I did not have two alternators I'd size
the battery for about 15 amps for alternator failed operation. Injectors
are about 12 ohms and run 80% duty at full power and in my case about
50% duty in cruise. Ignition is about 5 amps at full power but a little
less in cruise. Similarly the injectors draw a little bit more at full
power but in total only maybe an amp or less difference between full
power and cruise for the complete system.
My system would certainly be overkill for most folks but it has some
unique advantages in terms of simple emergency procedures,
troubleshooting, and redundancy. With recycled parts, the dollar and
weight cost was trivial if not the labor. 530 flight hours on the Murphy
Rebel as of this morning.
Ken
On 19/10/2013 9:09 PM, Robert L. Nuckolls, III wrote:
>
>
> At 04:01 PM 10/14/2013, you wrote:
>
>> On Oct 14, 2013, at 12:16 PM, Ken wrote:
>>
>>> You are in the ballpark Fred but it's probably safe to round down to
>>> 20 amps for a no alternator battery life calculation.
>>
>> Ken...thank you for your "3rd party validation"...at this stage of the
>> game, I'd rather be conservative, and I'm looking forward to Bob's
>> assessment.
>
> I think I'm down to the last missing data point.
>
> How do you switch between ECU modules? Do you have
> a wiring diagram of this feature you can sketch or scan
> to share?
>
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Jabiru 2200 voltage regulator again |
>
>Further study shows that Q1 and Q2 are to light a low voltage lite
>and are not part of a differential amplifier. Q3 and Q4 are for the
>regulator. My comment about the current limit on the zener still
>stands. circuit is from:
>http://www.aeroelectric.com/Pictures/Schematics/PM_Regulator/Kubota_Schematic.jpg
Yes, the circuit was dissected into two
functions at:
http://tinyurl.com/c8usyw2
http://tinyurl.com/c6doa97
. . . and you're right. The base-emitter junction of
Q4 in series with the hopefully small dynamic resistance
of the zener places the transistor at serious risk. This design
would not even come close to passing DO160 input voltage
tests. But then, not many garden tractors are subject
to the kinds of trash on the bus as airplanes.
I've not seen a schematic for a PM regulator that
offers warm-fuzzy feelings to an airplane jockey.
These bang-bang regulators have proven quite sufficient
for the lawn equipment markets and few folks have
complained about them in airplanes . . . at least
few to none here on the List. They may have a field
service history one step above dismal but not articulated
here.
If you're pondering a DIY project for a PM regulator,
consider adding some impedance in series with the
base of Q4. It doesn't need to be very big. The way
this thing is wired, the zener's operating current
is VERY low . . . a milliamp or less. Also poor design
practice . . . this is not up on the knee for predictable
conduction at the rated voltage. So 100 ohms in series
would protect the transistor and have very little
effect on regulation.
An adjustable regulator might modify the input circuit
to include a potentiometer which would add useful
base current protection for Q4. If you're up to brass-boarding
some experiments, I've had a few ideas for an upgrading
of the circuit's performance.
Bob . . .
________________________________________________________________________________
| From: | Earl Juno <earl_schroeder(at)juno.com> |
| Subject: | Re: Jabiru 2200 voltage regulator again |
I know a number of us would like to improve the Rotax regs...
Please continue! Thanks.
> On Oct 20, 2013, at 3:37 PM, "Robert L. Nuckolls, III"
wrote:
>
>
>
>>
>> Further study shows that Q1 and Q2 are to light a low voltage lite and are not part of a differential amplifier. Q3 and Q4 are for the regulator. My comment about the current limit on the zener still stands. circuit is from: http://www.aeroelectric.com/Pictures/Schematics/PM_Regulator/Kubota_Schematic.jpg
>
> Yes, the circuit was dissected into two
> functions at:
>
> http://tinyurl.com/c8usyw2
>
> http://tinyurl.com/c6doa97
>
> . . . and you're right. The base-emitter junction of
> Q4 in series with the hopefully small dynamic resistance
> of the zener places the transistor at serious risk. This design
> would not even come close to passing DO160 input voltage
> tests. But then, not many garden tractors are subject
> to the kinds of trash on the bus as airplanes.
>
> I've not seen a schematic for a PM regulator that
> offers warm-fuzzy feelings to an airplane jockey.
> These bang-bang regulators have proven quite sufficient
> for the lawn equipment markets and few folks have
> complained about them in airplanes . . . at least
> few to none here on the List. They may have a field
> service history one step above dismal but not articulated
> here.
>
> If you're pondering a DIY project for a PM regulator,
> consider adding some impedance in series with the
> base of Q4. It doesn't need to be very big. The way
> this thing is wired, the zener's operating current
> is VERY low . . . a milliamp or less. Also poor design
> practice . . . this is not up on the knee for predictable
> conduction at the rated voltage. So 100 ohms in series
> would protect the transistor and have very little
> effect on regulation.
>
> An adjustable regulator might modify the input circuit
> to include a potentiometer which would add useful
> base current protection for Q4. If you're up to brass-boarding
> some experiments, I've had a few ideas for an upgrading
> of the circuit's performance.
>
>
> Bob . . .
>
>
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Relay_for_Critical_Power_Feed |
Fooey,
Seems I'm having difficulties with integration of my
email and image editing tools and the List-Server.
I can email myself and the message comes through as
expected in both Eudora and Outlook . . . but there
appears to be a disconnect with the List Server.
Here's a .pdf of the message with missing images.
I'll get with Matt to see if we can resolve the
issues.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Jabiru 2200 voltage regulator again |
At 08:54 AM 10/21/2013, you wrote:
>
>
>I know a number of us would like to improve the Rotax regs...
>Please continue! Thanks.
Okay. The attached schematic is for a voltage regulator
(I'd leave that semi-worthless alt failure warn out).
Design goals:
Adjustable voltage regulation set point.
Improved thermal management
Tolerance to DO-160 abnormal voltage inputs
This would perform no better than the stock Rotax-
Ducati regulator except for design goals stated.
The second schematic deletes two transistors.
A first pass at the LM431 specs suggests that
the two extra stages of gain may not be
necessary.
A couple of experiments worth exploring . . .
Bob . . .
________________________________________________________________________________
| From: | rayj <raymondj(at)frontiernet.net> |
| Subject: | Re: Relay for Critical Power Feed |
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | EXP 2 Bus workaround |
All,
I would first of all like to thank all posters who have expanded
my understanding of the issues I face as I proceed w/ the wiring of my
aircraft...you have already helped me immeasurably to get to the revised
(proposed) circuit diagram below.
(I'm quite aware that "numbers" are still missing...but my
preference is to get my mind wrapped around the conceptual basis for
things before sizing wires.)
With full knowledge of my ignorance of all things electric but
with only scant knowledge of the challenges which lay ahead, some time
ago I purchased an EXP 2 Bus, thinking that having one would simplify
many issues and offset some of the novelty inherent with my auto engine
conversion, a MPEFIed derivative of a EA81 Subaru built by RAM
Performance Aero Engines which is liquid cooled. Aircraft is a Europa XS
monowheel, a fiber glass airframe, which is typically powered w/ a 912S
or 914.
I've been struggling to layout a circuit diagram which combines
the EXP 2 BUS configured for an external solenoid with the dual battery
/ single alternator diagram Z-19 in the "AeroElectric Connection".
I have made a number of decisions which have committed me to the
digital world including:
- an engine w/ electronic ignition, fuel injection, and an ECU (EC3,
Real World Systems) which came w/ the engine,
- a digital EMS (EM3, Real World Systems) which "talks" w/ the ECU,
- a digital EFIS (Skyview) including moving map, digital terrain,
Transponder, COM, and Intercom.
By selecting an auto engine conversion, I have committed to:
- one alternator, belt driven,
- one coolant pump, belt driven,
- single spark plug in each cylinder.
Additionally, in order to provide redundancy, the engine and
control system includes:
- dual batteries, presently planned to be Odyssey 680's,
- two independent high pressure fuel pumps, each w/ their own filter,
- independent back up battery for Skyview,
- independent back up battery for stand-alone GPS, Garmin 396,
- redundant motherboards (A and B) for the ECU which are toggled from
the panel.
OK...about the EXP BUS...I've now read many reports (including
the VAF threads) which point out its shortcomings...but having spent
$550 for it and its companion Indicator Module, and given my
inexperience and lack of knowledge of things electrical, I still believe
it has a place in my panel, so I hope any critique of what I'm up to
doesn't focus on simply getting rid of it...it sure seems to have value
to this electrical neophyte.
The EXP 2 Bus installation instructions can be downloaded at:
http://support.anywheremap.com/pdfs/EXP2-C.pdf
My approach to creating this circuit diagram has been an effort
to meld together the EXP Bus w/ the Z-19RB circuit diagram in the
AeroElectric Connection for "Dual Battery, Single Alternator, Electronic
Controlled Fuel Injection Engine w/ Rear Mounted Batteries"...(a copy of
which can be downloaded from:
http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/
I could use spare circuits in EXP BUS for the ECU, coils, fuel
injectors, and the fuel pumps, but I like the idea of being able to turn
off the master and keep the fan turning...therefore I have these
components powered via an Engine Bus.
I have space on my panel (just above the EXP BUS, and below the
Skyview flat screen) for a row of 6 - switches which are presently
planned to be:
- rocker or toggle between Fuel Pump #1 and Fuel Pump #2,
- Endurance Bus Alternate feed, on/off
- Battery #2, on/off
- ECU, on/off
- Fuel Injectors, on/off
- Coils, on/off
I also have space on my panel (between the COM/Intercom and the
ECU controller) for a row or two of CBs or fuses.
Attached are pixs of my instrument panel in its present state,
and a proposed circuit diagram. The intention of the circuit diagram is
to show:
- 2 batteries wired as one to allow staggered battery replacement to
ensure one of the two is relatively new and in excellent condition,
- EXP Bus to function as the main power distribution bus, powered from
Contactor #1 which is controlled by a master switch,
- Starter powered from Contactor #2 so that in-flight re-start is
possible w/ master off,
- Engine Bus (always hot) wired directly to the "battery side" of
Contactor #2
Note: For purposes of maintaining proper C of G, batteries and
contactors will be aft of the cabin.
I'd be extraordinarily grateful for any comments, and
particularly those which point out errors or weakness in the diagram or
the conceptual framework which the diagram is intended to address.
Fred
________________________________________________________________________________
| From: | "Jerald Folkerts" <jfolkerts1(at)gmail.com> |
I'm looking for a copy of the user/installation manual for the older
(pre-JPI) version of the VM1000C Engine Monitor. Please contact me offline
at jfolkerts1(at)gmail.com
Thanks,
Jerry Folkerts
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: elec. noise in antennas |
Last week I wrote:
>> I have been diligent in separating antenna wiring from power
wiring...in my fiberglass airframe, I molded in conduits along the sides
of the fuselage...all power wiring on the port side...antenna wiring and
pneumatics on starboard.
>>
>> My port conduit is getting pretty filled, and I have ample space in
the stbd conduit.
...and Bob N. responded by writing:
> There is no demonstrable value in separating antenna
> coax wires and other ship's wiring. The idea that
> 'noise' escapes ships wiring to invade the inner-sanctum
> of your coax is a poplar myth morphed into sage advice.
This leads me to another question:
With my battery aft of the cabin, if I put my starter feeder in my
starboard conduit and my battery ground wire in my port conduit, will
the SEPARATION of these two (most probably 4AWG) wires cause any
problems?
(I have one "advisor", a marine electrician, who is adamant that
separating those feeders will cause all manner of hurt in the form of
magnetic fields)
(I know nothing about magnetic fields, but it would seem to me that
separation of those wires would have zero consequences when the starter
is NOT engaged.)
Fred
________________________________________________________________________________
I'm in the process of hooking up the mag switches. My mags don't have a dedicated
ground terminal.
Is it standard practice to use one of the case screws?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411027#411027
Attachments:
http://forums.matronics.com//files/mags_140.jpg
http://forums.matronics.com//files/mags_164.jpg
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Mag grounding |
At 05:12 PM 10/21/2013, you wrote:
>
>I'm in the process of hooking up the mag switches. My mags don't
>have a dedicated ground terminal.
>
>Is it standard practice to use one of the case screws?
That works.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: elec. noise in antennas |
>With my battery aft of the cabin, if I put my starter feeder in my
>starboard conduit and my battery ground wire in my port conduit,
>will the SEPARATION of these two (most probably 4AWG) wires cause any problems?
>(I have one "advisor", a marine electrician, who is adamant that
>separating those feeders will cause all manner of hurt in the form
>of magnetic fields)
He is correct. Magnetic fields formed by OUTBOUND
electron flow in a wire is best managed by bringing
the INBOUND electrons on an adjacent wire . . . twisted
with it if practical but just getting the close an a
parallel as practical is good.
>(I know nothing about magnetic fields, but it would seem to me that
>separation of those wires would have zero consequences when the
>starter is NOT engaged.)
Alternator currents flow on those wires too during
recharge. About 20 years ago I talked with a guy
at OSH who had one of the Rutan Ez models. Seems
hitting starter spun his compass like a top and
turning the alternator on and off would swing
the compass to the tune of 20 degrees or more.
This has been a problem in steel tube aircraft
but especially composites. Do what you can to keep
these two conductors as parallel and adjacent
as practical.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 02:46 PM 10/21/2013, you wrote:
>All,
>
> I would first of all like to thank all posters who have
> expanded my understanding of the issues I face as I proceed w/ the
> wiring of my aircraft...you have already helped me immeasurably to
> get to the revised (proposed) circuit diagram below.
I have pondered your project while plowing the asphalt between
here an Wichita for two round trips . . . and made some notes.
I'll be publishing my recommendations (as if it were my airplane)
in the next day or so. We'll be able to integrate the EXP-Bus with
some degree of grace.
I can find no reason to run two batteries in your project. The
disparity of endurance demands between the e-bus and engine-bus
leaves watt-seconds left over on the e-bus . . . which means
your panel is still lit after the engine quits.
My proposal will used the existing 'master' switch in the
legacy task. The avionics master will be come the e-bus
alternate feed. We'll create an engine bus very much like
the e-bus with a diode feed from the main bus for normal ops
and and a fat alternate feed from the battery like the
e-bus.
This means you can trade second battery and contactor weight
in for a larger main battery that will make your planning
and maintenance for Plan-B contingencies much simpler, longer
endurance and more reliable.
Tell me about your fuel pumps. What controls or limits their
pressure? By the way, what is the operating pressure for
the system?
Still wondering about A/B ECU boards. Can you leave them
powered up and simply select between A and B from the
control panel. Does an ECU NOT selected draw the same
current as the one presently selected?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Relay_for_Critical_Power_Feed |
At 03:21 PM 10/21/2013, you wrote:
>Bob,
>
>FYI, The email you attached as a PDF came through to me as an email
>without any problems.
thanks. attachments seem to be fine . . . just embedded images
get hosed. Using the embedded image really makes a narrative
read better. I need to get this fixed.
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 21, 2013, at 4:45 PM, Robert L. Nuckolls, III wrote:
> I can find no reason to run two batteries in your project. The
> disparity of endurance demands between the e-bus and engine-bus
> leaves watt-seconds left over on the e-bus . . . which means
> your panel is still lit after the engine quits.
Bob...
I'm really surprised to here you say that...I've really bought into your
rationale for having 2 batteries of equal size so they can be rotated
out one at a time, raising the probability that one is always
(relatively) new...as for my endurance bus, I'd love to add my COM to
it. I think your rationale as I read it in the Connection is especially
appropriate for an engine which can't rely upon mags.
'I'll get answers for your other questions tomorrow...
Thanks for your insights into my installation,
Fred
________________________________________________________________________________
| Subject: | Re: Jabiru 2200 voltage regulator again |
| From: | Sacha <uuccio(at)gmail.com> |
> This would perform no better than the stock Rotax-
> Ducati regulator except for design goals stated.
Bob,
Assume you mean "no worse" in the sentence above ;)
Would you recommend switching out a Ducati regulator that's already installed (Kitfox,
Rotax 912, VFR Only)?
Sacha
________________________________________________________________________________
| Subject: | Unshielded wire for mags? |
| From: | Sacha <uuccio(at)gmail.com> |
What are the potential unwanted consequence of using unshielded wire for wiring
mags switches?
I just realized that's how my Kitfox is wired up but I can't hear any particular
interference in the headsets so far.
________________________________________________________________________________
| Subject: | hypothetical question |
| From: | "user9253" <fransew(at)gmail.com> |
I recently had a conversation with a pal who's had a solid background in marine
electrical/electronic work...a long time successful business after getting started
in the USN. We discussed wiring a hypothetical fiberglass airplane with
a rear mounted battery. I suggested running battery cables in integrated fiberglass
conduit with positive cables to starboard and negative to port side.
He claims that would be a big "no-no" as it would set up a powerful magnetic field
which would cause mayhem w/ radios. Unfortunately he did not have time to
elaborate on the mayhem.
I disagreed with his statement. I think there could be some noise on the radio
while cranking the engine, but that is of short duration. Is there a real
disadvantage to running positive wires on one side of the fuselage and negative
wires on the other side?
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411074#411074
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 11:57 PM 10/21/2013, you wrote:
On Oct 21, 2013, at 4:45 PM, Robert L. Nuckolls, III wrote:
I can find no reason to run two batteries in your project. The
disparity of endurance demands between the e-bus and engine-bus
leaves watt-seconds left over on the e-bus . . . which means
your panel is still lit after the engine quits.
Bob...
I'm really surprised to here you say that...I've really bought into
your rationale for having 2 batteries of equal size so they can be
rotated out one at a time, raising the probability that one is
always (relatively) new...as for my endurance bus, I'd love to add my
COM to it. I think your rationale as I read it in the Connection is
especially appropriate for an engine which can't rely upon mags.
I understand. It would help to review the history
of the two-battery concept:
The simplest, most reliable batteries are those which
receive periodic critical attention, like pre-flight
checks for fuel, oil, tire tread, controls, etc. The
battery is this smooth plastic box hidden away out
of sight and offers no observable data on it's
state of charge or ability to even take a charge.
Obviously, we cannot pre-flight a battery with the
same level of confidence as pulling out the dipstick
to check oil.
But we do know that batteries tend to fail gracefully,
sorta like the degradation of compression with the
service time on an engine or tread wear with numbers
of landings on tires. It is sufficient to check
your compression every annual (~50 hrs for average
light aircraft) or get out the tread wear gauge when
the tires are "looking a bit skinny".
Delving into the inner secrets of a battery is a
process with more complexity and requiring more tools
than peeking into a fuel tank or wiggling the stick
to make sure controls are intact and free.
The first driver for considering dual batteries was
to eliminate or at least shift the cost of ownership
for periodic polygraph testing of the battery. The
idea was simply cycle a new battery into a pair
of batteries every annual. The rationale for that
philosophy was based on the owner/operator's willingness
and dedication to the task of tracking the battery's
condition.
If you take the total cost of owning your airplane
and divide by hours flown, you come up with some
number. Rotating a new battery into the top of a pair
each annual will add (cost-of-battery/hours-flown)
to that other number. For many, the $time$ spent
on doing a battery change-out was more attractive
than taxation of $time$ to do the periodic battery
polygraph.
A second benefit of the dual battery architecture
was that it clearly divided endurance calculations,
planing and management into to camps. (1) engine
and (2) everything else that influenced battery-only
flying time. When I introduced the
e-bus concept 20+ years ago, it was no big deal to
craft a Plan-B wherein electrical system endurance
exceeded fuel endurance.
The people-paid-to-worry about airplanes tell us
that for the most part, 30 minutes of battery-only
endurance is enough. Perhaps so for the wizened ATP
pilot with 10,000 hours and a host of successfully
managed tense days in the cockpit. But for John Q
fliver-flyer with 600 hours, no intensive training
in airborne systems management and only flies
50-100 hours a year . . . it's another matter
entirely.
Hence my personal design goals for seeking ways
to assemble, maintain and operate systems with
considerably more than 30 minutes of battery-only
performance . . . preferably some number than
exceeds duration of fuel aboard.
So, in 4-5 hours of pondering your system here
on the List and on the road, I've divided your
battery only requirements into two piles. (1)
no-options loads like keeping the fires behind
the prop lit and (2) lighting up things on
the panel that are most useful for continued
cruising flight until a CONVENIENT, or better
yet, airport of intended destination is in
sight.
As a renter of certified airplanes, my personal plan-B
planning, maintenance and operation is necessarily
limited to stuff I carry in my flight bag. In other
words, from J3 to A36 Bonanza, I have no control
over the airplane so I plan to get where I want
to go wether the panel is lit up or not.
Now, you've got an engine that we THINK takes
about 10A to run. Getting one hour of endurance
requires a single battery having about 20 a.h.
capacity (when new) at the 20 hour rate. We know
that failure to benefit from ALL of a battery's
potential energy is a function of the battery's internal
resistance. So the proportion of energy tossed
off internally at any given discharge rate is
less if the battery is up-sized.
Another consideration for your airplane is
the value of partitioning system power into
two tasks (1) truly essential - keeping the
engine running and (2) optional - things on
the panel.
Okay, how does the Plan-B picture change if
your airplane is fitting with one, larger battery.
Several ways: First there is more incentive to
KNOW the state of your battery's health. This
means $time$ required for the periodic electrograph
as a preventative maintenance policy on the
airplane. But if you ran nothing but the
engine during no-alternator-ops, then the larger
single battery maximizes your endurance numbers
into something far more comfortable than that
30-minute thingy the paid-to-worry crowd is
so comfortable with . . . but then, NONE of
those folks are going to fly YOUR airplane.
Next, with one battery, you have the option
of turning OFF things that influence your
endurance capabilities . . . especially if
those capabilities are backed up by Plan-B1
hardware in the flight bag. So if your desired
destination is only an hour away, leave all
that stuff on. But you have the option of getting
2 hours plus endurance too.
Finally, this line of reasoning offers a much
simpler array of switches for which in-flight
decisions must be made. It offers a relatively
clean way to integrate the EXP-Bus into to
final design.
So armed with knowledge of battery condition,
time to fly to an airport of convenience then
you can simply choose what things on the panel
will be lit up or shut down. Maybe you can
go max-dark and fly hand-held until time
for descent and approach whereupon you turn
things back on. In this mode of flight, the
only thing other than engine specific loads
would be a voltmeter.
Based on this recent line of reasoning, I'm
wondering if elegance level Z-19 is really
as cool as I thought when the drawing was
crafted some years ago. It is perhaps and
example of the "too soon we get old, too late
we get smart" syndrome. But if that question
in going to get answered, I doubt that it
will happen more expeditiously than here
on the List . . . and you (along with your
airplane) may be the impetus for the effort.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Copper Foil width for VOR antenna |
| From: | "p32gxy" <p32gxy(at)gmail.com> |
Just an update... I am currently pursuing a loop antenna made out of Coax which
allows me to reduce it's size somewhat. I am looking at placing this antenna
inside the fuselage tailcone (all composite) and avoid the complications associated
with placing the VOR antenna in the wing.
I've ordered an VHF/UHF Vector Antenna Analyzer to tune this guy in place. I am
hoping that this "experiment" will go well.
Thanks everyone for your suggestions/comments.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411083#411083
________________________________________________________________________________
| From: | "Dr. Andrew Elliott" <a.s.elliott(at)cox.net> |
| Subject: | Re: Jabiru 2200 voltage regulator again |
Just some additional options - I am running an 18A John Deere PM
alternator in my plane and am using an aftermarket voltage regulator
designed for Harley. Nearly all motorcycles use PM alternators, and
these days cycles have all the fancy electronics like a plane or car.
Plus the regulators are designed to survive in a very hostile
environment. There are a number of good brands out there, including
Accel, Crane, Compu-Fire, Cycle Electric and others. (Of course, there
are also low-quality Chinese knock-offs, so buyer beware!)
My Crane Cams "Fireball" regulator is mounted behind the firewall,
directly on the metal side skin, so it can use some of that that as
additional cooling surface. The regulator runs through the B&C PM/OV
Filter & Protection kit (504-1). I have about 5 years and 550 hours on
the plane, mostly in the Arizona desert, with no problems at all in the
electrical system, FWIW.
Andy
------------------------
Andy Elliott, CL:480-695-9568
N601GE/Z601XL/TD/Corvair
525 hrs since 11/08
<http://servi-aero.com/n601ge/4sale/> Web Site Link
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Jabiru 2200 voltage regulator again |
At 02:13 AM 10/22/2013, you wrote:
> This would perform no better than the stock Rotax-
> Ducati regulator except for design goals stated.
Bob,
Assume you mean "no worse" in the sentence above ;)
Either. The modification will leave regulator
performance unchanged. But utility is improved
with adjustability and reliability is probably
improved by more robust management of BTUs and
abnormal bus voltages.
Would you recommend switching out a Ducati regulator that's already
installed (Kitfox, Rotax 912, VFR Only)?
I don't think so. It's sorta like that discussion
we've had on el-cheapo contactors. The over all
service life, cost of ownership and risk should drive
the decision.
At Beech, there were issues that rose to the top-ten
list of field service issues. Those got red-team
attention. Then there were things that generated
ADs against the airplane. Those were tiger-team
tasks. Stuff that didn't make the top ten were
subject to economic triage and generally handled
by competent and courteous field service reps.
Many airplanes are flying this rectifier/regulator
. . . the failure rate has bubbled up to at least
nuisance levels for some individuals but perhaps
not enough for red-team response by Rotax, Jariru,
et. als. For some flyers of engines with PM
alternators, it may be sufficient incentive for a
re-invention this particular wheel. It's one of
those self-interested, free-market exchange of
value decisions. I don't see it as much of a risk
issue.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Unshielded wire for mags? |
At 02:25 AM 10/22/2013, you wrote:
>
>What are the potential unwanted consequence of using unshielded wire
>for wiring mags switches?
>I just realized that's how my Kitfox is wired up but I can't hear
>any particular interference in the headsets so far.
All of the legacy prophylactics for noise abatement
are based on stand-alone evaluation of one system's
ability to generate noise verses the ability of other
systems to provide satisfactory operation in the
presence of noises that can never be zero.
I believe that ignition wires on a Rotax are
not nearly so prone to radiate noise as those
on a legacy magneto. If you're not experiencing
a problem, then your requirements to limit noise
have not exceeded the limits established by potential
victims of noise. If it ain't broke, don't fix it.
Bob . . .
________________________________________________________________________________
| From: | Charles Deiterich <cffd66(at)yahoo.com> |
| Subject: | Re: Jabiru 2200 voltage regulator again |
Bob,- =0A=0A=0ASorry for my ignorance, but how do I see your attachment?
lls, III" =0ASubject: Re: AeroElectric-List:
Jabiru 2200 voltage regulator again=0A=0AAt 08:54 AM 10/21/2013, you wrote
:=0A>=0A>=0A>I know a number of us would like to improve the Rotax regs...
=0A>Please continue!- Thanks.=0A=0A- Okay. The attached schematic is
for a voltage regulator=0A- (I'd leave that semi-worthless alt failure w
arn out).=0A
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: hypothetical question |
Subject: AeroElectric-List: hypothetical question
From: "user9253" <fransew(at)gmail.com>
I recently had a conversation with a pal who's had a solid background
in marine electrical/electronic work...a long time successful
business after getting started in the USN. We discussed wiring a
hypothetical fiberglass airplane with a rear mounted battery. I
suggested running battery cables in integrated fiberglass conduit
with positive cables to starboard and negative to port side. He
claims that would be a big "no-no" as it would set up a powerful
magnetic field which would cause mayhem w/ radios. Unfortunately he
did not have time to elaborate on the mayhem.
I disagreed with his statement. I think there could be some noise on
the radio while cranking the engine, but that is of short
duration. Is there a real disadvantage to running positive wires on
one side of the fuselage and negative wires on the other side?
Joe
He's right. Noise is a dynamic thing. I.e.
AC or at least modulated DC currents which
generate in turn, modulated magnetic fields.
An up-the-right, down=the-left configuration
of fat wires forms the primary of
a transformer. All potential victims
situated in the 'core' of that primary WIll
be influenced. Whether it's enough to be
noticed is a guess. But we DO know that
devices that measure static magnetics like
your whisky compass and/or magnetometers
are the most vulnerable.
The management of noise-bearing conductors
is simple-idea science irrespective of the
conductor's role as potential antagonist
or victim. Designing for cancellation of
influence or vulnerabilities using the
benefits of twisted pairs or at least
parallel conductors is inarguable.
That's why the earliest single-wire telephone
systems working against earth ground would
pick up static from local thunderstorms and
became unusable if the poles were shared by
AC power transmission lines.
When the phone company adopted end-to-end,
parallel/twisted pair topology, your phone wires
could traverse the worst of noise environments
with little or no effect. This is why audio
systems with parallel-concentric signal
paths would probably operate well within
such a loop. But the compass instrumentation
is another matter.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Copper Foil width for VOR antenna |
At 09:22 AM 10/22/2013, you wrote:
Just an update... I am currently pursuing a loop antenna made out of
Coax which allows me to reduce it's size somewhat. I am looking at
placing this antenna inside the fuselage tailcone (all composite) and
avoid the complications associated with placing the VOR antenna in the wing.
I've ordered an VHF/UHF Vector Antenna Analyzer to tune this guy in
place. I am hoping that this "experiment" will go well.
Thanks everyone for your suggestions/comments.
Look up loop antennas in the forums, websites
and journals for amateur radio enthusiasts.
Loop antennas can be adequate if not stellar
performers. But as Robert Heinlein once penned,
"their ain't no such thing as a free lunch".
Generally, any physical shortening of an antenna
requires some "tuning" reactances in the form of
inductors as loading coils or capacitors at
the ends as tuning devices. These added devices
alter the distribution of currents along your antenna's
conductors is ways that are almost never beneficial.
I recall that halo antennas for 2m were rather
narrow banded . . . on a ham band that was 4/146
or +/- 1.5% wide. Your VOR 'halo' range of interest
has a bandwidth of 113/10 or +/- 4.5% a bit
worse.
Fortunately, antennas for aviation are exceedingly
forgiving . . . especially receiving antennas that
watch 100W transmitters from line of sight distances.
So getting your antenna centered on the range of
interest for frequencies is task one. After that,
making quantitative measurements of performance
is at least tedious if not tricky. The analyzer
will measure impedances that can be plotted over
the range of interest but will be of no value
for predicting performance.
Probably the best thing a shade-tree pilot
cum antenna designer can do is install the
experiment. Go fly it. Then report performance
based on experience with other antennas in
rather broad terms of "works fine" or perhaps
not.
The time and effort that takes you from as
assessment of "adequate" to a quantified
plotting of one antenna against another is
a really big jump.
Please share your experiments and findings
with us. Pictures are good too.
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | EXP 2 Bus workaround |
Bob,
I appreciate your circumspection in taking another look at your twin battery rationale
as you stated it in the Connection. And I wrestle with what I see as inherent
contradictions in our quest for both fail-safe redundancy and simplicity...i.e.,
the more redundancy, the more complexity...fail-safe redundancy - good...increased
complexity - not so much.
A client of mine who certifies electrical and electronic systems for the big boys...I
can't state his company's role or authority in the proper terminology...absolutely
bemoans the aircraft industry's approach to solving problems in complex
systems by adding another layer of complexity.
Fred
________________________________________________________________________________
| Subject: | Landing gear warning trigger |
I need a trigger device for my gear up warning. The landing gear controller typically
uses a micro-switch that detects when the throttle is closed. The routing
of my fuel pressure and manifold pressure lines is going to make the mount
for such a switch very difficult.
My A&P mentioned that some aircraft use an adjustable pressure sensor tied in to
the manifold pressure line to accomplish this.
I'm wondering if anyone knows of a pressure sensor like this.
I'm also open to any other options that I can connect to the landing gear controller.
Thanks,
Don
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411104#411104
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Odyssey Batteries |
At 07:21 PM 10/21/2013, you wrote:
Hi Bob,
I took one of your seminars a few years ago at Ohio State University
Airport and now I have my Wittman Tailwind flying in phase one testing.
The problem I am having with an Oddessey battery PC925 is that it will not
start my Lycoming O-320 when it got to the mid 40s in temperature
overnight. I had the battery on a trickle charger overnight (Battery Tender
brand) and it showed it had charged enough (green led on control unit).
This is the second Oddessey battery I have had in the Tailwind, I had the
previous one replaced under warranty in May.
I need some guidance at troubleshooting this situation, when the battery
was first installed, it cranked the engine well. It has gotten
progressively slower at cranking despite being put on the trickle charger.
Recently after it would not start early in the morning, I put it on the
trickle charger and tried to start it again after lunch. It did start then,
just barely, and then I ran the engine for about 15 minutes to warm up the
oil. The engine has a 60 amp alternator (Nippon Denso) and the buss voltage
on my GRT EIS was 14.2-14.4 volts as the engine was running. After the 15
minute run, I shut off the engine and tried to restart after a couple of
minutes and the engine would not crank more than about 3 blades.
I realize that it is unlikely that I got bad battery to replace a bad
battery but I am not sure which component(s) to look at first. The battery,
starter, wiring and alternator are all things that may be causing the
problem but what to check first?
Thanks for your help, this got a little longer than I intended.
I agree that the likelihood of two bad batteries in
a row is very low. It's likely that some COMBINATION
of effects (voltage drops) are adding up to sabotage
cranking performance.
It's very difficult to do quantitative analysis of
a cranking circuit using a starter as a load. Engine
compression strokes and other variables in mechanical
loads on starter make it impossible to use a digital
meter to make any measurements . . . and still difficult
with an analog instrument.
Consider acquiring one of these tools from Harbor Freight.
Emacs!
http://tinyurl.com/3gnnwrt
Cut the gator-clips off leaving about 6"
of pigtails on each clip. Then install
ring terminals on the remaining leads to
the tester. Each terminal will get TWO
wires, one FAT one for load, one small
one for measuring voltage.
Then bolt the black lead to your
crankcase, the red lead to the UPSTREAM
side of the starter contactor. Build a
set of test leads for your multimeter
long enough to read battery in tail while
you are cranking knobs at the engine end
of the airplane.
Clip the voltmeter onto battery (-) and
battery (+) in the tail. Turn off as
many panel mounted electro-whizzies as
possible . . . pull breakers/fuses if
power switches are not part of the
system.
Turn battery switch ON. This should
produce a voltage on the test set that
is close to the battery voltage being read
in the tail.
Now, crank the handle up such that the
ammeter shows some handy big number.
200A is good. Get a quick reading of
battery volts and load-tester volts.
The battery volts number should be
commensurate with the battery's general
health. I would guess some value over
10 volts. The DIFFERENCE between battery
and tester volts is the value being LOST
in all the cranking system current path.
It should be no more than 1.0 volts.
If greater, then leave voltmeter(+) attached
to battery and move voltmeter (-) to the
tester (+) terminal on the starter contactor.
Repeat the 200A load event and measure the
drop.
Then move the voltmeter (-) back to the battery
(-) and voltmeter(+) to the crankcase. Repeat
the load event and measure the drop. This one
should be MUCH lower than the hot-side drop
measured above.
These three measurements will first identify
magnitude of drops fenced off into ground-side
and hot-side circuits. This is the data which
will guide your further investigation into
sources of cranking path resistance. These may
be combinations of contactors, terminals, wires
and bolted joints.
If the first measurement shows 1 volt or less
of loss, the only remaining variables to investigate
are starter contactor and/or starter performance.
You could move starter(+) lead from the
starter and bolt it to tester(+). Energize
the starter contactor and apply 200A load. See
what voltage is available to the starter at
this load.
As a general rule, there are no single sources
of debilitating voltage drop. A single
joint or contact set would burn up or at least
get really hot at 200A load. My guess is that
you're chasing a combination of drops, none
great enough to get noticeably warm . . . but
the sum total has crippled your otherwise
capable battery/starter combination.
When you're done with the testing, put some
terminals on the pigtails for the gator-clips,
bolt back onto the tester leads and cover
with heat shrink. This will return your tester
to useful battery testing service.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
| From: | rparigor(at)suffolk.lib.ny.us |
Hi Don
You can have a look at my throttle position sensor:
http://www.europaowners.org/main.php?g2_itemId=29497
Also have a look at the spring holding down the gear latch and the sensor
for that.
Ron Parigoris
"donjohnston"
> <don@velocity-xl.com>
>
> I need a trigger device for my gear up warning. The landing gear
> controller typically uses a micro-switch that detects when the
throttle is
> closed. The routing of my fuel pressure and manifold pressure lines
is
> going to make the mount for such a switch very difficult.
>
> My A&P mentioned that some aircraft use an adjustable pressure
sensor tied
> in to the manifold pressure line to accomplish this.
>
> I'm wondering if anyone knows of a pressure sensor like this.
>
> I'm also open to any other options that I can connect to the
landing gear
> controller.
>
> Thanks,
> Don
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=411104#411104
>
>
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 10:49 AM 10/22/2013, you wrote:
Bob,
I appreciate your circumspection in taking another look at your twin
battery rationale as you stated it in the Connection. And I wrestle
with what I see as inherent contradictions in our quest for both
fail-safe redundancy and simplicity...i.e., the more redundancy, the
more complexity...fail-safe redundancy - good...increased complexity
- not so much.
I think the seeds of the dual-battery tree
were planted by Lightspeed's early-on recommendations
for a second, diode maintained battery to insure
one source of power to a second ignition system.
A client of mine who certifies electrical and electronic systems for
the big boys...I can't state his company's role or authority in the
proper terminology...absolutely bemoans the aircraft industry's
approach to solving problems in complex systems by adding another
layer of complexity.
Sounds like a man who understands FMEA, MTBF
and the value of simplicity in the practical world
of human frailties.
Unfortunately, a lot of public ignorance of
risks exploited by Hollywood and driven by
individuals-paid-to-worry . . .
Emacs!
Your friend sounds like a good resource to review
ideas in this . . . what do I call it . . .
critical review of what may have been an under-developed
idea. Not necessarily a BAD idea but not the elegant
solution.
I'll try to get a drawing crafted to clarify my
thoughts in a form suitable for fielding review by
thoughtful observers.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Landing gear warning trigger |
At 10:55 AM 10/22/2013, you wrote:
>
>I need a trigger device for my gear up warning. The landing gear
>controller typically uses a micro-switch that detects when the
>throttle is closed. The routing of my fuel pressure and manifold
>pressure lines is going to make the mount for such a switch very difficult.
>
>My A&P mentioned that some aircraft use an adjustable pressure
>sensor tied in to the manifold pressure line to accomplish this.
>
>I'm wondering if anyone knows of a pressure sensor like this.
>
>I'm also open to any other options that I can connect to the landing
>gear controller.
>
>Thanks,
>Don
>
this seems a likely solution
http://tinyurl.com/oehkzu9
http://tinyurl.com/ofemkra
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Good guys in blue hats coming over the hill . . . |
It will be interesting to watch the evolution and market
experience with this battery. One wonders that given Boeing and
Cessna's experiences . . . what makes these guys think they
can stay up on the bull . . .
Of course, that's probably what they said about Henry Ford . . .
http://tinyurl.com/lsk7vbe
Bob . . .
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
rparigoris wrote:
> Hi Don
> You can have a look at my throttle position sensor:
> http://www.europaowners.org/main.php?g2_itemId=29497
> Also have a look at the spring holding down the gear latch and the sensor for
that.
> Ron Parigoris
Sorry... I should have been more clear. :(
I'm using a push/pull cable with a knob. The only way (I can see) to detect the
throttle position is with a switch at the engine end of the throttle cable.
But thanks anyway.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411129#411129
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
| From: | James Kilford <james(at)etravel.org> |
Don, do you have a photo? That might prompt some solutions.
James
On 22 October 2013 20:51, donjohnston <don@velocity-xl.com> wrote:
> don@velocity-xl.com>
>
>
> rparigoris wrote:
> > Hi Don
> > You can have a look at my throttle position sensor:
> > http://www.europaowners.org/main.php?g2_itemId=29497
> > Also have a look at the spring holding down the gear latch and the
> sensor for that.
> > Ron Parigoris
>
>
> Sorry... I should have been more clear. :(
>
> I'm using a push/pull cable with a knob. The only way (I can see) to
> detect the throttle position is with a switch at the engine end of the
> throttle cable.
>
> But thanks anyway.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=411129#411129
>
>
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
| From: | rparigor(at)suffolk.lib.ny.us |
Hi Don
I should have been more clear, I was hinting you could install a magnet
somewhere and have it trigger a reed switch. Don't know if feasible.
Home Depot sells rare earth magnets that are plenty strong with holes in
the center.
Ron P.
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
> Don, do you have a photo? That might prompt some solutions.
>
> James
Not sure that a photo would help here. There's nothing to take a picture of.
rparigoris wrote:
> Hi Don
> I should have been more clear, I was hinting you could install a magnet somewhere
and have it trigger a reed switch. Don't know if feasible. Home Depot sells
rare earth magnets that are plenty strong with holes in the center.
> Ron P.
I have a standard push/pull cable. It's completely encased. The only place to attach
anything would be at the end of the cable where it attaches to the air/throttle
inlet control. Which, in my situation, there's no way to put a bracket
to mount a switch or sensor to.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411149#411149
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
| From: | Jared Yates <email(at)jaredyates.com> |
Instead of throttle linkage position, could you use a manifold pressure transducer?
On Oct 22, 2013, at 18:57, "donjohnston" <don@velocity-xl.com> wrote:
>
>
>> Don, do you have a photo? That might prompt some solutions.
>>
>> James
>
>
> Not sure that a photo would help here. There's nothing to take a picture of.
>
>
>
> rparigoris wrote:
>> Hi Don
>> I should have been more clear, I was hinting you could install a magnet somewhere
and have it trigger a reed switch. Don't know if feasible. Home Depot
sells rare earth magnets that are plenty strong with holes in the center.
>> Ron P.
>
>
> I have a standard push/pull cable. It's completely encased. The only place to
attach anything would be at the end of the cable where it attaches to the air/throttle
inlet control. Which, in my situation, there's no way to put a bracket
to mount a switch or sensor to.
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=411149#411149
>
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
| From: | <berkut13(at)berkut13.com> |
| Subject: | Re: Landing gear warning trigger |
Huh? The cable itself has to have a bracket to hold the external shell
while the core moves freely. Why not attach the switch to that bracket and
feed a slave rod to it from the arm of the "whatever" you are running.
Still not enough information given.
Again, a picture of your carb/servo/throttle body and cable attachment would
help shed some light on the problem.
-James
-----Original Message-----
From: donjohnston
Sent: Tuesday, October 22, 2013 5:57 PM
Subject: AeroElectric-List: Re: Landing gear warning trigger
I have a standard push/pull cable. It's completely encased. The only place
to attach anything would be at the end of the cable where it attaches to the
air/throttle inlet control. Which, in my situation, there's no way to put a
bracket to mount a switch or sensor to.
________________________________________________________________________________
| Subject: | Re: hypothetical question |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
Let's take a loop 4 meters in diameter and put 200A through it. The magnet field
created is about 0.63 Gauss. This is about the same as the Earth's magnetic
field itself. So I wouldn't be too worried about it.
It is telling that your friend was a Navy man. The US navy knows more about the
Earth's magnetic field than anyone else. Reading the published naval papers on
the subject is fascinating. They degauss ships hulls (Philadelphia Experiment!),
and even know how the pounding of rough seas changes the magnetism of ships'
hulls over time.
Aircraft steel tubes magnetize over time and compass compensation is periodically
figured in. But of course, the Earth's magnetic field and its consistency is
not great either. For local use this is okay. No pilot ever used a compass for
long distances.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411199#411199
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
| From: | "user9253" <fransew(at)gmail.com> |
How about a RPM switch, all electronic with no moving parts?
Perhaps something like the attached untried circuit.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411200#411200
Attachments:
http://forums.matronics.com//files/rpm_switch_502.pdf
________________________________________________________________________________
| From: | Charles Brame <chasb(at)satx.rr.com> |
| Subject: | Re: Odyssey Batteries |
I couldn't find the original thread in the archives. So I hope this info
gets to the right builder.
I had a similar starting problem with a nearly new PC-680 a few years
ago, i.e., weak starts on my O-320, particularly on cold days. I also
was using a Battery Tender for charging. I called Odyssey to complain
and they said one is better off never charging than to use a Battery
Tender. Something about the Battery Tender not providing a high enough
initial charge resulting in the battery taking a lower than normal
voltage set. Odyssey sells a high dollar charger that they recommend.
However, based on info I got from Bob and others, I bought a Schumacher
1562 from WallMart for about $20. The Schumacher returned my PC-680 back
to life and it has started cold engines quickly for the last four years.
The Schumacher also rejuvenated a 10+ year old PC-680 and it has been
used to help start airplanes and autos all over the airport for several
years.
There is much in the archives regarding charging Odyssey batteries. The
Schumacher 1562 or equivalent is recommend in many threads.
Charlie Brame
RV-6A, N11CB
San Antonio
---------------------------------------------
Date: Oct 22, 2013
From: "Robert L. Nuckolls, III"
Subject: Re: Odyssey Batteries
At 07:21 PM 10/21/2013, you wrote:
Hi Bob,
I took one of your seminars a few years ago at Ohio State University
Airport and now I have my Wittman Tailwind flying in phase one testing.
The problem I am having with an Oddessey battery PC925 is that it will
not
start my Lycoming O-320 when it got to the mid 40s in temperature
overnight. I had the battery on a trickle charger overnight (Battery
Tender
brand) and it showed it had charged enough (green led on control unit).
This is the second Oddessey battery I have had in the Tailwind, I had
the
previous one replaced under warranty in May.
I need some guidance at troubleshooting this situation, when the battery
was first installed, it cranked the engine well. It has gotten
progressively slower at cranking despite being put on the trickle
charger.
Recently after it would not start early in the morning, I put it on the
trickle charger and tried to start it again after lunch. It did start
then,
just barely, and then I ran the engine for about 15 minutes to warm up
the
oil. The engine has a 60 amp alternator (Nippon Denso) and the buss
voltage
on my GRT EIS was 14.2-14.4 volts as the engine was running. After the
15
minute run, I shut off the engine and tried to restart after a couple of
minutes and the engine would not crank more than about 3 blades.
I realize that it is unlikely that I got bad battery to replace a bad
battery but I am not sure which component(s) to look at first. The
battery,
starter, wiring and alternator are all things that may be causing the
problem but what to check first?
Thanks for your help, this got a little longer than I intended.
I agree that the likelihood of two bad batteries in
a row is very low. It's likely that some COMBINATION
of effects (voltage drops) are adding up to sabotage
cranking performance.
It's very difficult to do quantitative analysis of
a cranking circuit using a starter as a load. Engine
compression strokes and other variables in mechanical
loads on starter make it impossible to use a digital
meter to make any measurements . . . and still difficult
with an analog instrument.
________________________________________________________________________________
| Subject: | Re: hypothetical question |
| From: | "user9253" <fransew(at)gmail.com> |
That reminds me of a story that a college professor, who was also an electrical
inspector, teaching the national electrical code told the class about an electrician
who did a very neat job. At the service entrance panel, he put all of
the white wires in one conduit and all of the black wires in another conduit.
It looked very nice and the inspector passed it. After the business moved into
the building, they noticed that the conduit was getting hot. They called
the inspector to complain about it. The inspector then realized that when both
white and black wires are in the same conduit, their magnetic fields cancel
each other out. But if they are in separate conduits, then the magnetic fields
are not cancelled. The rising and falling 60 Hz magnetic fields generate heat
in the metal conduit.
But that was alternating current. We are dealing with DC in an airplane. The
magnetic field around a wire carrying DC does not change unless the current
is changing. Albeit, the DC is not pure but has an AC ripple.
I agree that the magnetic field around a wire can affect a compass. The instructions
that come with a new compass say to twist the wires feeding the compass
light. But will magnetic fields cause mayhem with the radios?
The magnetic fields surrounding two wires, carrying opposite current, oppose
each other. I saw a film of a service panel whose load was faulted with hundreds
of amps. The parallel conductors were forced apart by the large magnetic
fields developed by the fault current. Since the magnetic fields of parallel
conductors oppose each other, that makes me think that they do not cancel each
other, at least not in the area right next to a wire.
Twisting of wires is what cancels induced currents in nearby conductors. Induced
current caused by one twisted wire is cancelled by the opposing induced current
caused by the other twisted wire.
Now consider a metal airplane where electrical currents from various loads all
flow though the airframe back to the source (alternator or battery). If anything
is going to cause interference, many currents flowing though the same conductor
will. Also consider a bundle of wires carrying positive current to various
loads. In that bundle are antenna coax and exterior lighting wires and
fuel pump wires and etc. But the radios work just fine. There could be reasons
to separate wires of opposite polarity. For instance, in a metal airplane,
the airframe can be used as one conductor. In a plastic airplane, there could
be mechanical situations where there is only room for one large conductor.
Or perhaps it is desired to keep always hot wires separated to prevent a short
circuit in case of a crash.
I am not disagreeing with anything that Bob said. Keeping positive and negative
wires together and twisted is good practice. I am asking if positive and
negative wires are separated in homebuilt aircraft, will there be significant
interference to radios?
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411223#411223
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 21, 2013, at 4:45 PM, Robert L. Nuckolls, III wrote:
> Still wondering about A/B ECU boards. Can you leave them
> powered up and simply select between A and B from the
> control panel. Does an ECU NOT selected draw the same
> current as the one presently selected?
Bob,
ECU manual states:
There are separate power inputs for the A and B controllers. If your
electrical system has a back up power bus you can connect the B
controller to it. Otherwise tie both A and B power inputs together.
Tracy Crook just emailed:
Yes, both controllers draw current when either one is selected, Also,
BOTH power inputs must be supplied with 12 volts when in operation.
Total Current draw is less than 1/2 amp.
If we proceed w/ an Engine Bus w/ alternate feed, it appears to me that
both A and B would best be tied together.
Fred
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Odyssey Batteries |
At 10:57 AM 10/23/2013, you wrote:
I couldn't find the original thread in the archives. So I hope this
info gets to the right builder.
I had a similar starting problem with a nearly new PC-680 a few years
ago, i.e., weak starts on my O-320, particularly on cold days. I also
was using a Battery Tender for charging. I called Odyssey to complain
and they said one is better off never charging than to use a Battery
Tender. Something about the Battery Tender not providing a high
enough initial charge resulting in the battery taking a lower than
normal voltage set. Odyssey sells a high dollar charger that they
recommend. However, based on info I got from Bob and others, I bought
a Schumacher 1562 from WallMart for about $20. The Schumacher
returned my PC-680 back to life and it has started cold engines
quickly for the last four years. The Schumacher also rejuvenated a
10+ year old PC-680 and it has been used to help start airplanes and
autos all over the airport for several years.
There is much in the archives regarding charging Odyssey batteries.
The Schumacher 1562 or equivalent is recommend in many threads.
Good data. I had forgotten about those exchanges.
I'm not sure I understand the physics of the "low
initial charge" . . . I'll have to dig around in
the books on that. To be sure, the 1562 is probably
the best bargain out there.
Bruce, if your load tests at 200A drop the battery
to less than 10v, you might want to drop by Walmart
and pick up one of the Schumacher 1562 chargers. Walmart
is showing these on sale at the moment for $17.00.
http://tinyurl.com/m464b8d
I've owned several over the past 10+ years. Except for gross
failures, they've performed well on all size batteries
in my instrumentation herds.
A side note, a couple of 32 a.h. SVLA batteries
I've had for at least the past 10 years finally
gave up the ghost. Cells on the end of the stack
swelled up like a toad. These batteries were not
Odyssey products . . . both were Panasonic. The
last time I cap-checked them was about 4 years
ago and they were still turning in numbers
of 24+ a.h. at a 4 amp rate.
I don't think I've ever load-tested these batteries.
They were never used for cranking . . . only for
running portable instrumentation systems. The SLVA
can demonstrate exemplar performance.
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
Bob...you asked about my fuel pumps and pressures...
The fuel pressure at idle is 38 psi; at wot it rises to 43 psi.
The pressure is controlled by a regulator which sits on what my guy calls a "fuel
log" which sets on the tops of the cylinders...I can provide photo if necessary.
Fred
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Battery charger/maintainers |
Odyssey claims that a Battery Tender (and I presume
Battery Minders with charge rates under 1A are incapable of
charging an Odyssey product due to "low initial charge
rates(?)"
I have long thought that a lead-acid product
of any capacity would eventually achieve a full
state of charge at any rate . . . as long as the
top-off voltage plateau was reached and held for
a substantial period of time . . . say 1 hour
or more.
I've never owned an Odyssey but I've used Battery-Tender
charger-maintainers for years on batteries up through
33 a.h. and found that the batteries took some time to
charge but cap-checked pretty much as expected. It's
not clear to me how would an Odyssey be that much different
than a Panasonic.
I found some test data I gathered on two wall-warts
(a Tender and a Minder) along with the Schumacher 1562
Emacs!
A Battery Minder I tested does not appear to accomplish a true
top-off cycle. On the other hand, the Battery Tender does seem to
conduct a top-off . . .
Emacs!
But the real value in $low$ charger/maintainers seems to be the
Schumacher 1562
Emacs!
The 1562 is about 2/3 the cost of the wall-warts, about twice
the "initial charge" rate and exhibits a robust/practical
implementation of a top-off cycle.
I have Battery Tenders in my shop . . .which seem to have served
me well . . . along with the 1562's for years.
Data shown above gives me pause to wonder if people do not make a
distinction between Battery Tenders and Battery Minders.
It's the Battery Minder that may be the bad-boy on the
street.
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | EXP 2 Bus workaround |
Bob...this latest iteration of diagram is my effort, striving for
elegance, to incorporate your suggestions which I present as follows:
- Wire the engine bus via a diode feed from the 2, 11amp AUX circuits on
the EXP Bus; provide an alternate feed from the battery via an "Engine
Bus Alternate Feed Relay".
- Wire the endurance bus via a diode feed from a 7 amp circuit on the
EXP Bus; provide an alternate feed from the engine bus via an "Endurance
Bus Alternate Feed Relay".
- Regarding the re-wiring and re-labeling of some of the EXP Bus
rockers, I've deviated from your suggestions after considering the
following rationale and thinking about having a simple organization if
things go south:
Let the row of EXP Bus rockers serve for normal ops;
i.e., power up the ECU, the fuel injectors, and the coils using the 3
rockers furthest to the left, currently labeled
"I GN", "AUX", and "Clrnc Del"...(for my anticipated ops, clearance
delivery will be rarely used).
Let the space above the EXP Bus be for switches used
during emergencies; i.e., switch from fuel pump #1 to fuel pump #2;
switch engine bus to alternate feed, and endurance bus to alternate feed
(both feeds direct to battery, if EXP Bus or alternator go out.
- One battery and master contactor are shown, but I'm inclined to leave
open for now the option for dual batteries and rotating out one of them
periodically.
All comments most appreciated.
Fred
________________________________________________________________________________
| From: | Tim Olson <Tim(at)MyRV10.com> |
| Subject: | Re: Battery charger/maintainers |
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 01:50 PM 10/23/2013, you wrote:
>Bob...this latest iteration of diagram is my effort, striving for
>elegance, to incorporate your suggestions which I present as follows:
>
>- Wire the engine bus via a diode feed from the 2, 11amp AUX
>circuits on the EXP Bus; provide an alternate feed from the battery
>via an "Engine Bus Alternate Feed Relay".
Okay, getting closer.
(1) Recommend you take the engine bus normal feedpath directly
from the main bus through the diode. A normal Engine ON/OFF
switch in this path seems to make sense see (6).
(2) add 30A maxi fuse in series with Engine Bus Alternate
Feed path and being engine power forward on 10AWG wire.
(3) Take E-Bus alternate feed directly from the battery on
it's own 7A fuse and 14AWG wire . . . 10A fuse if determined
necessary later.
(4) Go to solid state relays for e-bus and E-bus alternate
feeds, either Eric's or ours.
(5) Run #2 fuel pump from main bus through polyfuse and
EXP Bus switch.
(6) I see no value in having separate switches for
injectors, coils, normal pump or ECU feed. One switch
in normal feed path for normal engine ops, one switch
to control alternate feed path. When and why would you
ever operate one of these switches independently of
the others. Two ways to power engine . . . normal and
alternate.
(7) Suggest separate fuses for each injector and coil
assuming engine produces some useable power with any
one fuse open.
(8) Starter can control from main bus.
(9) Turn existing avionics bus into e-bus, convert
old avionics master into alternate feed path control
switch. Normal feed path comes from main bus through
diode.
(10) You speak to "room for breakers/fuses on panel"
suggest these be out of sight, of reach.
Bob . . .
________________________________________________________________________________
| From: | "Bill Bradburry" <bbradburry(at)bellsouth.net> |
| Subject: | EXP 2 Bus workaround |
Fred,
What is the switch "Clrnc Del" used for in the normal install? Is this a
second avionics master to use to get a clearance prior to starting the
engine??
Bill
_____
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Fred
Klein
Sent: Wednesday, October 23, 2013 2:51 PM
Subject: AeroElectric-List: EXP 2 Bus workaround
Bob...this latest iteration of diagram is my effort, striving for elegance,
to incorporate your suggestions which I present as follows:
- Wire the engine bus via a diode feed from the 2, 11amp AUX circuits on the
EXP Bus; provide an alternate feed from the battery via an "Engine Bus
Alternate Feed Relay".
- Wire the endurance bus via a diode feed from a 7 amp circuit on the EXP
Bus; provide an alternate feed from the engine bus via an "Endurance Bus
Alternate Feed Relay".
- Regarding the re-wiring and re-labeling of some of the EXP Bus rockers,
I've deviated from your suggestions after considering the following
rationale and thinking about having a simple organization if things go
south:
Let the row of EXP Bus rockers serve for normal ops;
i.e., power up the ECU, the fuel injectors, and the coils using the 3
rockers furthest to the left, currently labeled
"I GN", "AUX", and "Clrnc Del"...(for my anticipated ops, clearance delivery
will be rarely used).
Let the space above the EXP Bus be for switches used
during emergencies; i.e., switch from fuel pump #1 to fuel pump #2; switch
engine bus to alternate feed, and endurance bus to alternate feed (both
feeds direct to battery, if EXP Bus or alternator go out.
- One battery and master contactor are shown, but I'm inclined to leave open
for now the option for dual batteries and rotating out one of them
periodically.
All comments most appreciated.
Fred
________________________________________________________________________________
| Subject: | Re: hypothetical question |
| From: | "user9253" <fransew(at)gmail.com> |
I searched the internet for magnetic fields surrounding parallel conductors and
found out that if current is flowing in the opposite direction in two conductors,
the magnetic fields repel each other. The magnetic fields do not cancel
each other out. Instead they become distorted. The fields extend out less in
the direction of the other wire, and they extend out farther in the opposite
direction. Here is a picture of the distorted magnetic fields:
http://www.physchem.co.za/OB11-ele/graphics/magnetic1_f8.gif
>From this I conclude that running wires of opposite polarity close together and
in parallel does not reduce the magnetic field surrounding the wires. If devices
are sensitive to magnetic interference, they should be kept far away from
wires carrying large currents.
If the magnetic fields do not cancel, how to explain the phenomenon in my previous
post about conduit becoming hot when white and black AC wires are segregated,
but the conduit remains cool with both white and black wires contained within
one conduit? The current induced in the conduit by white wires is opposed
by current induced by black wires. Thus, no eddy current flows and the conduit
remains cool. But magnetic fields that surround each conductor are not cancelled.
A steady DC current will not induce voltages in adjacent wires.
A DC current with a large AC ripple can induce voltage in adjacent wires.
Twisting the positive and negative wires of a circuit together will minimize induced
voltage in adjacent wires. If the positive and negative antagonistic wires
are too big to be twisted together, and they are causing interference, then
they should be isolated.
Other views and comments are welcome.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411276#411276
________________________________________________________________________________
| Subject: | Alternator without a Battery |
| From: | Thomas E Blejwas <tomblejwas(at)yahoo.com> |
In designing the electrical system for my Zenith Zodiac with a Viking engine, I
thought I would start with Z-19 and modify - add OVP for the alternator, a relay
to prevent run-on of the starter, and maybe more. Recent discussions on this
site about contactors and the Z-19 philosophy have me rethinking things.
Also, the Viking has an alternator that can run without a battery. I remember
driving an overloaded old Dodge Colt on a long evening trip (Christmas eve) and
having the headlights go dimmer and dimmer. Fortunately, I made it to a gas
station next to a motel, because the battery that had easily started the engine
4 hours earlier was very shorted. (I was able to get a used battery installed
on Christmas Day by a great farmer with a tow truck.). Why don't we worry
about this in airplanes? Shouldn't we be able to fully disconnect the battery
or batteries, if the alternator can run without a battery? Thanks.
Tom
Sent from my iPad
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 23, 2013, at 5:03 PM, Bill Bradburry wrote:
> What is the switch =93Clrnc Del=94 used for in the normal install? Is
this a second avionics master to use to get a clearance prior to
starting the engine??
Bill...I suppose you could call it that...the Clearance Delivery is on a
"keep alive" 3 amp circuit w/ its own on/off switch intended for
communication w/ tower w/o turning on your whole panel prior to engine
start up...Fred
________________________________________________________________________________
| Subject: | Re: hypothetical question |
| From: | Sacha <uuccio(at)gmail.com> |
>> I searched the internet for magnetic fields surrounding parallel conductors
and found out that if current is flowing in the opposite direction in two conductors,
the magnetic fields repel each other. The magnetic fields do not cancel
each other out. Instead they become distorted. The fields extend out less
in the direction of the other wire, and they extend out farther in the opposite
direction. Here is a picture of the distorted magnetic fields:
>> http://www.physchem.co.za/OB11-ele/graphics/magnetic1_f8.gif
Hi Joe
It's a question of scale. The fields do not cancel out exactly because the two
wires carrying current in opposite directions are not in exactly the same spot.
But If you move sufficiently far away from the pair of wires then the magnetic
field effectively cancels out. What does sufficiently far mean in this context?
Well if one goes through the calculations the critical distance d is the
distance between the center of the two conductors. So if they're kept very
close together (eg by twisting) then as long as you are at a distance D away from
the pair, where D is much greater than d, then the magnetic field becomes
very small. Typically d is of the order of a few millimeters so if you're eg
a meter away, then D is hundreds of times greater than d and the magnetic field
is for all intents and purposes zero.
Sacha
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Alternator without a Battery |
At 08:18 PM 10/23/2013, you wrote:
In designing the electrical system for my Zenith Zodiac with a Viking
engine, I thought I would start with Z-19 and modify - add OVP for
the alternator, a relay to prevent run-on of the starter, and maybe
more. Recent discussions on this site about contactors and the Z-19
philosophy have me rethinking things.
Good critical review is always a good thing, if only
to confirm the validity of our faith in legacy
philosophies. Such confirmation fosters understanding.
Also, the Viking has an alternator that can run without a
battery. I remember driving an overloaded old Dodge Colt on a long
evening trip (Christmas eve) and having the headlights go dimmer and
dimmer. Fortunately, I made it to a gas station next to a motel,
because the battery that had easily started the engine 4 hours
earlier was very shorted. (I was able to get a used battery
installed on Christmas Day by a great farmer with a tow truck.). Why
don't we worry about this in airplanes? Shouldn't we be able to
fully disconnect the battery or batteries, if the alternator can run
without a battery?
. . . the Barons and Bonanzas do it, perhaps other airplanes
too. Your mission, if you choose to accept it, is to evaluate
the science and risks for adopting this philosophy yourself.
A discussion and study of stand-alone alternator operation
would be a good thing.
Bob . . .
________________________________________________________________________________
| From: | "Sacha" <uuccio(at)gmail.com> |
| Subject: | Alternator without a Battery |
> A discussion and study of stand-alone alternator operation would be a
good thing.
Yes. I think the internal rotax 912 alternator/ducati regulator combination
will do this but I wouldn't want to do any damage by just disconnecting the
battery and seeing what happens. What's a safe way to test this?
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
> Again, a picture of your carb/servo/throttle body and cable attachment would
> help shed some light on the problem.
Okay. Here's some pic's. Hopefully they'll help.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411310#411310
Attachments:
http://forums.matronics.com//files/img_20131023_115542_266a_166.jpg
http://forums.matronics.com//files/img_20131023_115520_014a_204.jpg
________________________________________________________________________________
| From: | John W Livingston <livingjw(at)earthlink.net> |
| Subject: | Re: hypothetical question |
Perfectly stated.
On 10/24/2013 2:13 AM, Sacha wrote:
>
>>> I searched the internet for magnetic fields surrounding parallel conductors
and found out that if current is flowing in the opposite direction in two conductors,
the magnetic fields repel each other. The magnetic fields do not cancel
each other out. Instead they become distorted. The fields extend out less
in the direction of the other wire, and they extend out farther in the opposite
direction. Here is a picture of the distorted magnetic fields:
>>> http://www.physchem.co.za/OB11-ele/graphics/magnetic1_f8.gif
> Hi Joe
> It's a question of scale. The fields do not cancel out exactly because the two
wires carrying current in opposite directions are not in exactly the same spot.
But If you move sufficiently far away from the pair of wires then the magnetic
field effectively cancels out. What does sufficiently far mean in this
context? Well if one goes through the calculations the critical distance d is
the distance between the center of the two conductors. So if they're kept very
close together (eg by twisting) then as long as you are at a distance D away
from the pair, where D is much greater than d, then the magnetic field becomes
very small. Typically d is of the order of a few millimeters so if you're eg
a meter away, then D is hundreds of times greater than d and the magnetic field
is for all intents and purposes zero.
> Sacha
>
>
________________________________________________________________________________
| From: | John W Livingston <livingjw(at)earthlink.net> |
| Subject: | Re: Landing gear warning trigger |
Seems to me that an aluminum bracket and a micro-switch would do the job.
John
On 10/24/2013 9:57 AM, donjohnston wrote:
>
>
>> Again, a picture of your carb/servo/throttle body and cable attachment would
>> help shed some light on the problem.
>
> Okay. Here's some pic's. Hopefully they'll help.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=411310#411310
>
>
> Attachments:
>
> http://forums.matronics.com//files/img_20131023_115542_266a_166.jpg
> http://forums.matronics.com//files/img_20131023_115520_014a_204.jpg
>
>
________________________________________________________________________________
| Subject: | Re: hypothetical question |
| From: | "user9253" <fransew(at)gmail.com> |
Thanks for clarifying that, Sacha.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411315#411315
________________________________________________________________________________
| From: | <berkut13(at)berkut13.com> |
| Subject: | Re: Landing gear warning trigger |
Yep. You already have a fabricated bracket and two anchor bolts available
close by. I'd just re-make the existing bracket (or add a new one) to
extend toward the lever arm and mount a micro switch. You could put an 'L'
shaped tab on the arm using the existing hole to contact the switch if you
need to move the assembly inboard to clear the fuel line.
Or like I mentioned before, mount the switch remotely and activate it with a
slave rod (piano wire) from the lever arm...on either side (push or pull can
work). That's a little more complicated but allows you to work around space
limitations or obstructions if needed.
Simple stuff...bunches of various options. I see no real need for something
complex.
BTW, I hope this you have already addressed this - that mounting clamp looks
not to be fully secured. You dont want to "pre-disaster" yourself and have
the throttle linkage come loose in flight. Just checking.
-James
Berkut/Race 13
EAA Tech Advisor
-----Original Message-----
From: donjohnston
Sent: Thursday, October 24, 2013 8:57 AM
Subject: AeroElectric-List: Re: Landing gear warning trigger
> Again, a picture of your carb/servo/throttle body and cable attachment
> would
> help shed some light on the problem.
Okay. Here's some pic's. Hopefully they'll help.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411310#411310
Attachments:
http://forums.matronics.com//files/img_20131023_115542_266a_166.jpg
http://forums.matronics.com//files/img_20131023_115520_014a_204.jpg
________________________________________________________________________________
| From: | Charles Brame <chasb(at)satx.rr.com> |
| Subject: | Battery charger/maintainers |
Bob,
In my case, the problem child was/is, very definitely, a Battery Tender.
Of note, I do have a Battery Tender, Jr. on a SLVA battery that I bought
from a computer store, sort of a cheap PC-680 knockoff (12 volts and 17
a.h.) The battery runs an electric gate on my driveway. The Battery
Tender, Jr. has maintained that battery for nearly ten years now with no
problems ever noted. Of course, the gate doesn't require the battery
performance compared to that necessary to start an airplane.
Charlie Brame
RV-6A, N11CB
San Antonio
------------------------------------------------------------------
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: AeroElectric-List: Battery charger/maintainers
Odyssey claims that a Battery Tender (and I presume
Battery Minders with charge rates under 1A are incapable of
charging an Odyssey product due to "low initial charge
rates(?)"
I have long thought that a lead-acid product
of any capacity would eventually achieve a full
state of charge at any rate . . . as long as the
top-off voltage plateau was reached and held for
a substantial period of time . . . say 1 hour
or more.
I've never owned an Odyssey but I've used Battery-Tender
charger-maintainers for years on batteries up through
33 a.h. and found that the batteries took some time to
charge but cap-checked pretty much as expected. It's
not clear to me how would an Odyssey be that much different
than a Panasonic.
I found some test data I gathered on two wall-warts
(a Tender and a Minder) along with the Schumacher 1562
Emacs!
A Battery Minder I tested does not appear to accomplish a true
top-off cycle. On the other hand, the Battery Tender does seem to
conduct a top-off . . .
Emacs!
But the real value in $low$ charger/maintainers seems to be the
Schumacher 1562
Emacs!
The 1562 is about 2/3 the cost of the wall-warts, about twice
the "initial charge" rate and exhibits a robust/practical
implementation of a top-off cycle.
I have Battery Tenders in my shop . . .which seem to have served
me well . . . along with the 1562's for years.
Data shown above gives me pause to wonder if people do not make a
distinction between Battery Tenders and Battery Minders.
It's the Battery Minder that may be the bad-boy on the
street.
Bob . . .
________________________________ Message 10 ______________
________________________________________________________________________________
| From: | "Dennis Johnson" <pinetownd(at)volcano.net> |
| Subject: | Any French Electricians? |
Greetings,
This is not an aviation question, so feel free to delete now.
I have a table saw in my workshop with a 3 HP, 240 volt, 60 Hz motor.
It was made in France for the US market. After 25 years of faithful
service, the motor won't start. It hummed and the saw blade moved
slightly, but that was all. The motor has two capacitors. The markings
on one of them were readable and I installed a replacement. The other
capacitor was mounted on the outside case of the motor and the markings
were painted over when the motor was painted at the factory.
The motor's data plate indicates two capacitors: one at 500 microfarads
and the other at 30 microfarads at 400 volts AC. I replaced the 500
microfarad capacitor because it had leaked some oil and, since I could
read the markings on the case, it was easy to get a replacement. The
saw now starts, but just barely; much slower than it used to. I suspect
the other capacitor may also need to be replaced. However, I do not
know if it is a momentary (start) capacitor or a continuous run
capacitor since there are no markings on the case. The case is about
the side of two "D" cell flashlight batteries stacked end to end..
I might take this to an electric motor repair shop and let them figure
it out, but I'm curious if anyone can translate the attached schematic,
which was folded up inside the motor's electrical wiring box. I can
figure out the names for the colors of the wires, but not much else.
I'm interested in not only what the words translate into English, but
what the symbols mean. I'm using this as an opportunity to learn
something about larger AC electric motors.
I have a Fluke 87 meter with a capacitor measurement function, but it
only works on polarized capacitors. Mine are not polarized, since they
are for AC current.
Best,
Dennis
________________________________________________________________________________
| From: | "Peter Mather" <peter(at)mather.com> |
| Subject: | Any French Electricians? |
The capacitor connected to the violet wires is the start capacitor, the one
to the black wires is the run capacitor. The motor is dual voltage (as per
the data plate). The diagram shows high voltage operation. To use it in low
voltage mode connect the white, orage and red wires to post W2. You can
reverse rotation by swapping the black and red wires.
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Dennis
Johnson
Sent: 24 October 2013 17:22
Subject: AeroElectric-List: Any French Electricians?
Greetings,
This is not an aviation question, so feel free to delete now.
I have a table saw in my workshop with a 3 HP, 240 volt, 60 Hz motor. It
was made in France for the US market. After 25 years of faithful service,
the motor won't start. It hummed and the saw blade moved slightly, but that
was all. The motor has two capacitors. The markings on one of them were
readable and I installed a replacement. The other capacitor was mounted on
the outside case of the motor and the markings were painted over when the
motor was painted at the factory.
The motor's data plate indicates two capacitors: one at 500 microfarads and
the other at 30 microfarads at 400 volts AC. I replaced the 500 microfarad
capacitor because it had leaked some oil and, since I could read the
markings on the case, it was easy to get a replacement. The saw now starts,
but just barely; much slower than it used to. I suspect the other capacitor
may also need to be replaced. However, I do not know if it is a momentary
(start) capacitor or a continuous run capacitor since there are no markings
on the case. The case is about the side of two "D" cell flashlight
batteries stacked end to end..
I might take this to an electric motor repair shop and let them figure it
out, but I'm curious if anyone can translate the attached schematic, which
was folded up inside the motor's electrical wiring box. I can figure out
the names for the colors of the wires, but not much else. I'm interested in
not only what the words translate into English, but what the symbols mean.
I'm using this as an opportunity to learn something about larger AC electric
motors.
I have a Fluke 87 meter with a capacitor measurement function, but it only
works on polarized capacitors. Mine are not polarized, since they are for
AC current.
Best,
Dennis
________________________________________________________________________________
| From: | "Sacha" <uuccio(at)gmail.com> |
| Subject: | Any French Electricians? |
Hi Dennis,
Here you go. hope it's helpful.
Sacha
Motor with starter and permanent condensers (capacitors) without thermal
protection. Double voltage.
Next to the condensers on the schematic:
C.D= Condensateur de Demarrage = starter condenser
C.P. = Condensateur Permanent = permanent condenser
The schematic is drawn for LOW voltage. For HIGH voltage, connect the white
and orange wires to W2.
Direction of Rotation: Anti-clockwise as seen from the connection
(connector?)
To reverse the sense of rotation invert the black and red wires.
Not sure what PP and PA mean both preceeded by 1/2. Next to the rotating
disc, it says something which I interpret as: "the PA half which is less
resistant" on top of the disc and "the PA half which is more resistant" on
the bottom of the disc.
I'm not sure what the symbol on the Purple (VIOLET) wire is next to the
capacitor.
________________________________________________________________________________
| From: | "Sacha" <uuccio(at)gmail.com> |
| Subject: | Any French Electricians? |
=D8 The capacitor connected to the violet wires is the start capacitor,
the
one to the black wires is the run capacitor.
Yes
The motor is dual voltage (as per the data plate). The diagram shows
high
voltage operation. To use it in low voltage mode connect the white,
orage
and red wires to post W2.
I believe it=92s the opposite way round - it shows low voltage operation
and
you need to connect the orange and white to W2 for high volt op.
________________________________________________________________________________
| From: | "David Lloyd" <skywagon(at)charter.net> |
| Subject: | Re: Battery charger/maintainers |
I too use several Battery Tenders (BY) &/or the 1562 model sold by Sears
and others. Early on, I found that some maintainers ship from the
factory with either the high point and float level voltages set
incorrectly.
In the early models of the BT (and, maybe still . .) the case could be
removed and inside were two mini-pots that could be adjusted for the
correct high and float voltage points.
My suggestion to anyone using these units to at least check the float
voltage after the battery and maintainer have stabilized. Using your
trusty DVM check that the float voltage is about 13.2 v. on a 12 v.
battery. A higher float voltage might gas the battery in long term
storage mode depending on its chemistry health.
D
-------------------------------------------------------------------------
-------
----- Original Message -----
From: Charles Brame
To: List AeroElectric
Sent: Thursday, October 24, 2013 9:10 AM
Subject: AeroElectric-List: Battery charger/maintainers
Bob,
In my case, the problem child was/is, very definitely, a Battery
Tender.
Of note, I do have a Battery Tender, Jr. on a SLVA battery that I
bought from a computer store, sort of a cheap PC-680 knockoff (12 volts
and 17 a.h.) The battery runs an electric gate on my driveway. The
Battery Tender, Jr. has maintained that battery for nearly ten years now
with no problems ever noted. Of course, the gate doesn't require the
battery performance compared to that necessary to start an airplane.
Charlie Brame
RV-6A, N11CB
San Antonio
------------------------------------------------------------------
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: AeroElectric-List: Battery charger/maintainers
Odyssey claims that a Battery Tender (and I presume
Battery Minders with charge rates under 1A are incapable of
charging an Odyssey product due to "low initial charge
rates(?)"
I have long thought that a lead-acid product
of any capacity would eventually achieve a full
state of charge at any rate . . . as long as the
top-off voltage plateau was reached and held for
a substantial period of time . . . say 1 hour
or more.
I've never owned an Odyssey but I've used Battery-Tender
charger-maintainers for years on batteries up through
33 a.h. and found that the batteries took some time to
charge but cap-checked pretty much as expected. It's
not clear to me how would an Odyssey be that much different
than a Panasonic.
I found some test data I gathered on two wall-warts
(a Tender and a Minder) along with the Schumacher 1562
Emacs!
A Battery Minder I tested does not appear to accomplish a true
top-off cycle. On the other hand, the Battery Tender does seem to
conduct a top-off . . .
Emacs!
But the real value in $low$ charger/maintainers seems to be the
Schumacher 1562
Emacs!
The 1562 is about 2/3 the cost of the wall-warts, about twice
the "initial charge" rate and exhibits a robust/practical
implementation of a top-off cycle.
I have Battery Tenders in my shop . . .which seem to have served
me well . . . along with the 1562's for years.
Data shown above gives me pause to wonder if people do not make a
distinction between Battery Tenders and Battery Minders.
It's the Battery Minder that may be the bad-boy on the
street.
Bob . . .
________________________________ Message 10 ______________
________________________________________________________________________________
| From: | "Peter Mather" <peter(at)mather.com> |
| Subject: | Any French Electricians? |
Sacha is correct - finger trouble on my part
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Sacha
Sent: 24 October 2013 18:04
Subject: RE: AeroElectric-List: Any French Electricians?
=D8 The capacitor connected to the violet wires is the start capacitor,
the
one to the black wires is the run capacitor.
Yes
The motor is dual voltage (as per the data plate). The diagram shows
high
voltage operation. To use it in low voltage mode connect the white,
orage
and red wires to post W2.
I believe it=92s the opposite way round - it shows low voltage operation
and
you need to connect the orange and white to W2 for high volt op.
________________________________________________________________________________
| From: | "Thomas Barter" <kesleyelectric(at)iowatelecom.net> |
| Subject: | Any French Electricians? |
The symbol connected to the violet wires to the right of the capacitor is
the rotating governor/stationary switch, which disconnects the start
capacitor when the motor reaches approx. 80-90% rated speed. The connection
as shown is for low voltage.
Tom Barter
Kesley Electric, Inc.
Phone (319)-347-2462
Fax (319)-347-6607
kesleyelectric(at)iowatelecom.net
_____
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Sacha
Sent: Thursday, October 24, 2013 12:04 PM
Subject: RE: AeroElectric-List: Any French Electricians?
* The capacitor connected to the violet wires is the start capacitor,
the one to the black wires is the run capacitor.
Yes
The motor is dual voltage (as per the data plate). The diagram shows high
voltage operation. To use it in low voltage mode connect the white, orage
and red wires to post W2.
I believe it's the opposite way round - it shows low voltage operation and
you need to connect the orange and white to W2 for high volt op.
________________________________________________________________________________
| From: | Bob McCallum <robert.mccallum2(at)sympatico.ca> |
| Subject: | Any French Electricians? |
Motor with capacitors for start and run not thermally protected dual voltag
e
bleu = blue
blanc = white
orange = orange
jaune = yellow
rouge = red
violet = violet
noir = black
cd = start capacitor
cp = run capacitor
LOW voltage shown=2C for high voltage connect white=2C orange and red wires
to terminal W2
rotation anti-clockwise viewed from connection end
to change rotation interchange red and black wires.
The round symbol in the violet lead is the centrifugal switch to switch in
and out the start winding.
Bob McC
From: uuccio(at)gmail.com
Subject: RE: AeroElectric-List: Any French Electricians?
Date: Thu=2C 24 Oct 2013 18:03:47 +0100
=0A
=D8 The capacitor connected to the violet wires is the start capacitor=2C
the one to the black wires is the run capacitor. YesThe motor is dual volta
ge (as per the data plate). The diagram shows high voltage operation. To us
e it in low voltage mode connect the white=2C orage and red wires to post W
2. I believe it=92s the opposite way round - it shows low voltage operation
and you need to connect the orange and white to W2 for high volt op. =0A
=0A
=0A
=0A
============0A
============0A
============0A
============0A
=0A
________________________________________________________________________________
| Subject: | Re: Any French Electricians? |
| From: | Eric Page <edpav8r(at)yahoo.com> |
Dennis,
My French is pretty rusty, but I came up with this:
The title reads, roughly: "MOTOR STARTUP CAPACITORS AND PERMANENT (word miss
ing?) WITHOUT THERMAL PROTECTION. DUAL VOLTAGE."
Colors:
Bleu = Blue
Blanc = White
Jaune = Yellow
Rouge = Red
Noir = Black
Bottom notes:
"LOW VOLTAGE DRAWING: For high voltage connect the white, orange and red wir
es to terminal number W2." =94 I think that means the drawing shows l
ow voltage connection and the note explains high voltage connection.
"ROTATION: Counter-clockwise as seen from connection." =94 I suspect
"connection" is used in the mechanical sense, meaning the output shaft.
"To change the direction of rotation, reverse black and red."
Good luck!
Eric
On Oct 24, 2013, at 9:21 AM, "Dennis Johnson" wrote:
> Greetings,
>
> This is not an aviation question, so feel free to delete now.
>
> I have a table saw in my workshop with a 3 HP, 240 volt, 60 Hz motor. It w
as made in France for the US market. After 25 years of faithful service, th
e motor won't start. It hummed and the saw blade moved slightly, but that w
as all. The motor has two capacitors. The markings on one of them were rea
dable and I installed a replacement. The other capacitor was mounted on the
outside case of the motor and the markings were painted over when the motor
was painted at the factory.
>
> The motor's data plate indicates two capacitors: one at 500 microfarads a
nd the other at 30 microfarads at 400 volts AC. I replaced the 500 microfar
ad capacitor because it had leaked some oil and, since I could read the mark
ings on the case, it was easy to get a replacement. The saw now starts, but
just barely; much slower than it used to. I suspect the other capacitor ma
y also need to be replaced. However, I do not know if it is a momentary (st
art) capacitor or a continuous run capacitor since there are no markings on t
he case. The case is about the side of two "D" cell flashlight batteries st
acked end to end..
>
> I might take this to an electric motor repair shop and let them figure it o
ut, but I'm curious if anyone can translate the attached schematic, which wa
s folded up inside the motor's electrical wiring box. I can figure out the n
ames for the colors of the wires, but not much else. I'm interested in not o
nly what the words translate into English, but what the symbols mean. I'm u
sing this as an opportunity to learn something about larger AC electric moto
rs.
>
> I have a Fluke 87 meter with a capacitor measurement function, but it only
works on polarized capacitors. Mine are not polarized, since they are for A
C current.
>
> Best,
> Dennis
>
>
________________________________________________________________________________
| Subject: | Re: EXP 2 Bus workaround |
| From: | "user9253" <fransew(at)gmail.com> |
Looking at the EXP 2 Bus Installation Manual
http://support.anywheremap.net/pdfs/EXP2-C.pdf
Page 15 has a simplified schematic. In the lower right hand corner are 2 diodes,
D10 and D12, that can power the engine. The diodes are powered by two separate
circuits: the MAIN BUS and the BACKUP BUS which can get its power directly
from the battery through J31.
The problem is trying to convert the avionics bus into an endurance bus. There
does not appear to be an avionics mechanical relay. It looks like a solid
state relay with an ON-OFF input and a START DISABLE input. Without having the
board in hand, it is hard to say how to bypass this device with a diode. Another
problem is how to feed the avionics bus with a second power input from an
E-bus relay.
Notice in the upper right hand corner is diode D3. What is that for? When would
current ever want to flow in the opposite direction? The only thing that
I can think of is that it is a misguided attempt to prevent voltage spikes from
the master contactor coil. But any induced current will flow with the diode,
not in the opposite direction. Am I overlooking something?
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411341#411341
________________________________________________________________________________
| Subject: | Re: Odyssey Batteries |
| From: | Gordon Parker <gptailwind(at)gmail.com> |
I had a very simular starting problem early on with my tailwind with Lyc.
160 until I changed out the battery cable to a #2 welding cable. No more
problems. Gordon
On Wed, Oct 23, 2013 at 8:57 AM, Charles Brame wrote:
> I couldn't find the original thread in the archives. So I hope this info
> gets to the right builder.
>
> I had a similar starting problem with a nearly new PC-680 a few years ago
,
> i.e., weak starts on my O-320, particularly on cold days. I also was usin
g
> a Battery Tender for charging. I called Odyssey to complain and they said
> one is better off never charging than to use a Battery Tender. Something
> about the Battery Tender not providing a high enough initial charge
> resulting in the battery taking a lower than normal voltage set. Odyssey
> sells a high dollar charger that they recommend. However, based on info I
> got from Bob and others, I bought a Schumacher 1562 from WallMart for abo
ut
> $20. The Schumacher returned my PC-680 back to life and it has started
> cold engines quickly for the last four years. The Schumacher also
> rejuvenated a 10+ year old PC-680 and it has been used to help start
> airplanes and autos all over the airport for several years.
>
> There is much in the archives regarding charging Odyssey batteries. The
> Schumacher 1562 or equivalent is recommend in many threads.
>
> Charlie Brame
> RV-6A, N11CB
> San Antonio
>
> ---------------------------------------------
>
> *Date:**Oct 22, 2013**From:**"Robert L. Nuckolls, III" **Subject:**Re: Odyssey Batteries <http://www.matronics.com
/searching/getmsg_script.cgi?INDEX=116834357?KEYS=odyssey_batteries?LIS
TNAME=AeroElectric?HITNUMBER=1?SERIAL=0826451382?SHOWBUTTONS=NO>*
>
>
> At 07:21 PM 10/21/2013, you wrote:
> Hi Bob,
> I took one of your seminars a few years ago at Ohio State University
> Airport and now I have my Wittman Tailwind flying in phase one testing.
>
> The problem I am having with an Oddessey battery PC925 is that it will no
t
> start my Lycoming O-320 when it got to the mid 40s in temperature
> overnight. I had the battery on a trickle charger overnight (Battery Tend
er
> brand) and it showed it had charged enough (green led on control unit).
>
> This is the second Oddessey battery I have had in the Tailwind, I had the
> previous one replaced under warranty in May.
>
> I need some guidance at troubleshooting this situation, when the battery
> was first installed, it cranked the engine well. It has gotten
> progressively slower at cranking despite being put on the trickle charger
.
>
> Recently after it would not start early in the morning, I put it on the
> trickle charger and tried to start it again after lunch. It did start the
n,
> just barely, and then I ran the engine for about 15 minutes to warm up th
e
> oil. The engine has a 60 amp alternator (Nippon Denso) and the buss volta
ge
> on my GRT EIS was 14.2-14.4 volts as the engine was running. After the 15
> minute run, I shut off the engine and tried to restart after a couple of
> minutes and the engine would not crank more than about 3 blades.
>
> I realize that it is unlikely that I got bad battery to replace a bad
> battery but I am not sure which component(s) to look at first. The batter
y,
> starter, wiring and alternator are all things that may be causing the
> problem but what to check first?
>
> Thanks for your help, this got a little longer than I intended.
>
> I agree that the likelihood of two bad batteries in
> a row is very low. It's likely that some COMBINATION
> of effects (voltage drops) are adding up to sabotage
> cranking performance.
>
> It's very difficult to do quantitative analysis of
> a cranking circuit using a starter as a load. Engine
> compression strokes and other variables in mechanical
> loads on starter make it impossible to use a digital
> meter to make any measurements . . . and still difficult
> with an analog instrument.
>
>
> *
>
===========
===========
===========
===========
> *
>
>
________________________________________________________________________________
| Subject: | Re: Any French Electricians? |
| From: | "Dennis Johnson" <pinetownd(at)volcano.net> |
Thanks so much for everyone who took the time to respond to my request for a translation
and explanation of my French-made table saw motor schematic! I always
feel good when I learn something new and I feel even better that so many people
helped me. Thanks!
Dennis
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411346#411346
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Odyssey Batteries |
At 02:00 PM 10/24/2013, you wrote:
>I had a very simular starting problem early on
>with my tailwind with Lyc. 160 until I changed
>out the battery cable to a #2 welding cable. No more problems. Gordon
What size wired did you take out?
Bob . . .
________________________________________________________________________________
| Subject: | Re: Odyssey Batteries |
| From: | Gordon Parker <gptailwind(at)gmail.com> |
What size wire did I replace. Don't remember,however it was an aircraft
wire and was aluminum and much smaller.
On Thu, Oct 24, 2013 at 12:38 PM, Robert L. Nuckolls, III <
nuckolls.bob(at)aeroelectric.com> wrote:
> nuckolls.bob(at)aeroelectric.com**>
>
> At 02:00 PM 10/24/2013, you wrote:
>
>> I had a very simular starting problem early on with my tailwind with Lyc
.
>> 160 until I changed out the battery cable to a #2 welding cable. =C3=82
No more
>> problems. =C3=82 Gordon
>>
>
> What size wired did you take out?
>
>
> Bob . . .
>
>
=====**===================
===========**=
/www.matronics.com/Navigator?AeroElectric-List>
=====**===================
===========**=
=====**===================
===========**=
com/contribution>
=====**===================
===========**=
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Battery charger/maintainers |
At 12:17 PM 10/24/2013, you wrote:
>I too use several Battery Tenders (BY) &/or the 1562 model sold by
>Sears and others. Early on, I found that some maintainers ship from
>the factory with either the high point and float level voltages set
>incorrectly.
>In the early models of the BT (and, maybe still . .) the case could
>be removed and inside were two mini-pots that could be adjusted for
>the correct high and float voltage points.
>My suggestion to anyone using these units to at least check the
>float voltage after the battery and maintainer have
>stabilized. Using your trusty DVM check that the float voltage is
>about 13.2 v. on a 12 v. battery. A higher float voltage might gas
>the battery in long term storage mode depending on its chemistry health.
My good friend Skip Koss at Concorde reminds
me that the Battery Minder brand has expanded
over the years to include a constellation of battery
maintenance products.
http://tinyurl.com/mzn8z92
Skip says Concorde has evaluated and endorsed the S2
model for their batteries . . . he said and I
quote, "Bob, the charge curve on the 1562 looks like
the BatteryMINDER "S2" curve that we endorse,
except that the BatteryMINDER has an ambient temperature
sensor that regulates the charging and float (OCV)
voltage at temperatures from -40 to 140F perfectly,
can be and SHOULD be left on these hanger queens
24/7 and their batteries will last them 8-10 years."
No doubt the data under which we've labored
since I pitched a BatteryMinder wall wart based on
a gimpy recharge curve 10 years ago is probably
invalid. Everybody has had a chance to
run the marketplace race and I suspect that the
original prohibitions against BatteryMinder
are inappropriate.
Similarly, Battery Tender's stable of products
has blossomed too.
http://tinyurl.com/q6qq637
Bottom line is that either of these brands have
earned a fresh look at present performance.
It's highly probable that Schumacher's technology
has evolved as well. I'll pick up a new 1562
and run the plot. Until more data is known,
my opinion as to the performance/value of this
product is unchanged . . . but new numbers could
break that bubble in a heartbeat.
Bob . . .
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: Landing gear warning trigger |
Just a thought. A simple trigger for a gear warning on my amphib, that
has worked rather well, is to use the master caution light on my EIS as
the trigger. I programmed a min rpm warning on the EIS 6000 that is
armed only after climb rpm has been reached or exceeded like several
other warnings. It triggers when rpm is reduced to below cruise values.
In my case an additional verbal audio warning then cycle continues until
the gear hydraulic pressure is brought up to normal. Of course like any
warning, it only works well if you rarely or never get nuisance master
caution warnings.
Ken
On 24/10/2013 11:25 AM, berkut13(at)berkut13.com wrote:
>
> Yep. You already have a fabricated bracket and two anchor bolts
> available close by. I'd just re-make the existing bracket (or add a new
> one) to extend toward the lever arm and mount a micro switch. You could
> put an 'L' shaped tab on the arm using the existing hole to contact the
> switch if you need to move the assembly inboard to clear the fuel line.
>
> Or like I mentioned before, mount the switch remotely and activate it
> with a slave rod (piano wire) from the lever arm...on either side (push
> or pull can work). That's a little more complicated but allows you to
> work around space limitations or obstructions if needed.
>
> Simple stuff...bunches of various options. I see no real need for
> something complex.
>
> BTW, I hope this you have already addressed this - that mounting clamp
> looks not to be fully secured. You dont want to "pre-disaster"
> yourself and have the throttle linkage come loose in flight. Just
> checking.
>
> -James
> Berkut/Race 13
> EAA Tech Advisor
>
>
> -----Original Message----- From: donjohnston
> Sent: Thursday, October 24, 2013 8:57 AM
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Re: Landing gear warning trigger
>
> <don@velocity-xl.com>
>
>
>> Again, a picture of your carb/servo/throttle body and cable attachment
>> would
>> help shed some light on the problem.
>
>
> Okay. Here's some pic's. Hopefully they'll help.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=411310#411310
>
>
> Attachments:
>
> http://forums.matronics.com//files/img_20131023_115542_266a_166.jpg
> http://forums.matronics.com//files/img_20131023_115520_014a_204.jpg
>
>
________________________________________________________________________________
| From: | Ralph Finch <ralphmariafinch(at)gmail.com> |
| Subject: | Re: Battery charger/maintainers |
Aviation Consumer (September 2011) had a comparison of battery chargers.
Here's their conclusion:
*Our Winner
*There really is no contest; the VDC BatteryMINDer aviation chargers win in
all departments, except price. But for that price you get what you pay for.
You get an aviation-specific, simple-to-use, full-featured,
temperature-compensated, powerful charger capable of charging up to three
batteries at once, or one battery much faster and safer than any other
charger tested. About the only other time you will find a temperature probe
other than the BatteryMINDer is with costly, deep-cycle marine/RV chargers
costing many hundreds of dollars.
There are two different BatteryMINDer charging profiles for aircraft
batteries (S2 and S3) and two different voltages (12 and 24), so read the
VDC aviation Web page section carefully or ask them for help, but the Web
site is quite clear.
The S2 models are for Concorde batteries (AGM and flooded) and Gill (AGM
and flooded) batteries. The S3 models are for the expensive Gill LT Series
AGM and Odyssey/Hawker batteries.
Prices on the VDC Web site for the top recommended models 12248-AA-S2 and
S3 (12-volt) and 24041-AA-S2 and S3 (24-volt) BatteryMINDer series are in
the $198 price range. For now, they are including a free digital
multi-meter as part of this charger purchase. There are also European
versions that operate from 220/240 volts.
Until withdrawn, they are offering a trade-up from any type/brand
non-aviation specific charger (including their own non-aviation types) at a
substantial discount from their suggested retail. Offer details are
available on the first page of the aviation section of their Web site
www.battery-minders.com.They also have two types of solar panels with
controllers for inside the airplane, as well as super charger/25-amp,
24-volt power supply combination unit, model 28252-AA.
________________________________________________________________________________
| Subject: | Re: EXP 2 Bus workaround |
| From: | Fred Klein <fklein(at)orcasonline.com> |
Joe...see indents below within your text...Fred
On Oct 24, 2013, at 11:34 AM, user9253 wrote:
>
> Looking at the EXP 2 Bus Installation Manual
> http://support.anywheremap.net/pdfs/EXP2-C.pdf
> Page 15 has a simplified schematic. In the lower right hand corner are 2 diodes,
D10 and D12, that can power the engine. The diodes are powered by two separate
circuits: the MAIN BUS and the BACKUP BUS which can get its power directly
from the battery through J31.
The "simplified schematic" on p. 15 shows the optional back up battery diodes;
this is a factory mod which I do not have. My EXP is better described by the
schematic on p. 13 (Typical install w/ Ext. Solenoid...factory supplied jumper
replaces the Master Relay K1)...however, the AUX1 and AUX2 circuits are mislabled
and are 11 amps, not 7 amps as shown.
> The problem is trying to convert the avionics bus into an endurance bus. There
does not appear to be an avionics mechanical relay. It looks like a solid
state relay with an ON-OFF input and a START DISABLE input. Without having the
board in hand, it is hard to say how to bypass this device with a diode. Another
problem is how to feed the avionics bus with a second power input from
an E-bus relay.
I am loath to alter the innards of the EXP, other than perhaps re-lable and re-purpose
a couple of the rocker switches and wiring them accordingly. My latest
proposed circuit diagram shows a separate E-bus fed thru a diode from a 7 amp
circuit off the EXP Avionics bus, with an alternate feed thru a relay from
the engine bus. I'm content to allow the Avionics Bus to remain as is, noting
that both GPS and Skyview do not move to the E-bus as they both have stand alone
back up batteries. It's no accident that this thread is named "workaround".
> Notice in the upper right hand corner is diode D3. What is that for? When
would current ever want to flow in the opposite direction? The only thing that
I can think of is that it is a misguided attempt to prevent voltage spikes from
the master contactor coil. But any induced current will flow with the diode,
not in the opposite direction. Am I overlooking something?
These things I cannot commentt on...
> Joe
>
> --------
> Joe Gores
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=411341#411341
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
| Subject: | Re: Alternator without a Battery |
| From: | Richard Girard <aslsa.rng(at)gmail.com> |
>From the Rotax Installation Manual, Section 24-00-00, page 7:
"A capacitor (see fig. 11, pos 14) of at least 22000 uF/25V is necessary to
protect the correct function of regulator and to flatten voltage. The
regulator is not designed to store any electrical charge. If for any reason
the battery or bus system is disconnected from the regulator while the
engine is running (i.e. the master switch is shut off) the capacitor will
safely absorb and dissipate the electrical charge produced by the
generator. Otherwise the regulator would be damaged."
Rick Girard
On Thu, Oct 24, 2013 at 8:52 AM, Sacha wrote:
>
> > A discussion and study of stand-alone alternator operation would be a
> good thing.
>
> Yes. I think the internal rotax 912 alternator/ducati regulator
> combination
> will do this but I wouldn't want to do any damage by just disconnecting the
> battery and seeing what happens. What's a safe way to test this?
>
>
--
Zulu Delta
Mk IIIC
Thanks, Homer GBYM
It isn't necessary to have relatives in Kansas City in order to be unhappy.
- Groucho Marx
________________________________________________________________________________
| Subject: | Re: AeroElectric-List Digest: 27 Msgs - 10/24/13 |
| From: | Jay Bannister <jaybannist(at)cs.com> |
Does anyone know where I can get a schematic of the internal wiring of a TC
M Bendix mag/starter switch (BDX 10-357200-1) ?
Thanks - Jay Bannister
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
Attached are the preliminary sketches for my current
thoughts on an architecture for single battery, single
alternator, electrically dependent engine. This line of
thinking is being developed as an preferred alternative
to Z-19.
This architecture has roots in Z-11 Three-Bus structure
with the addition of a Motive Power Bus (engine). With
the term E-bus already in legacy use, the MP-Bus terminology
offers a stand-out label that avoids confusion.
The major difference is the addition of the MP-bus having
normal feedpath from the main bus, alternate feedpath from
the battery . . . same as the E-Bus except BOTH pathways
have panel mounted switches. The e-bus is always hot any
time the main bus is hot, but the MP-Bus as power to the
engine needs to be controlled through both pathways.
I'm thinking that the EXP-bus can be folded into this
architecture by conversion of battery switch to DC master
and take alternator field through second pole. Convert
the 'avionice master' Engine A. Use switch between the
big red rockers as e-bus alternate feed. Switch to right
of Engine A is Engine B.
Old avionics bus becomes e-bus. Add fuse-block with
sufficient slots to accommodate MP-Bus loads.
Solid state relays in the alternate feed paths is
an option. Nothing wrong with the legacy automotive
plastic cube relays here but the DO draw about 100
mA each. Two relays in the battery only mode consumes
as much energy as another accessory . . . solid state
relays will consume a milliamp or so. That's a decision
that is not germane to current identification of loads
and shuffling them to the right bus.
Fred, if you would make a list of how the various
electrical loads would be distributed along these four
busses, I can move forward with a refinement of the
idea specific to your airplane. Don't worry about circuit
protection or wire sizing . . . just a list of everything
that gets a protected feeder and which bus you would
attach it to.
The next phase of the EXP-Bus workaround involves a
head-count of protected load-taps from existing e-bua
and main bus structures on the EXP-Bus assembly . . .
and distributing those load-taps amongst proposed
electro-whizzies. The MP-Bus is easy since it's an
external addition and not limited as to numbers of
load taps.
The relative risk factors for this architecture are
driven by the same factors that have been part-and-parcel
of owning and operating an airplane of any genre' whether
OBAM or TC.
KNOW YOUR BATTERY and it's EXPECTED DUTIES to meet
DESIGN GOALS for battery only operations. Then maintain
that capability as religiously as you change oil, tires
or use safety wire on prop bolts.
The two-battery band-aid is, perhaps, not as great
a risk mitigation as we once thought. This has been
a good exercise in the sifting of bits and pieces.
Critical review solicited and welcomed.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Electrically driven accidents |
I have received the blessings of my client for conversion
of some aircraft accident investigation work-product into
teaching tools. Tools that illustrate the "Been there, done
that, let's don't do it again" sort of teaching.
I've cherry picked the items I produced and published
them in the N811HB directory on my website under
"Accidents."
http://tinyurl.com/ky7szec
The videos were crafted to give a gaggle of attorneys
some background of the technical issues with the idea
that material would be tailored and re-assembled
into work-product suited to show to a jury. The case
settled so the draft videos were never superceded.
Hence the mediocre production values.
There's a narrative of the accident as published by
the NTSB, a series of videos that explore a portion
of the electrical system dedicated to supplying
power to the ignition systems and one picture that
illustrates the manner in which a Dual-Feed, Ignition
Power Bus was implemented in this airplane.
Several of the videos speak to the value for
following instructions along with risk for failure to
reduce a system to the simplest, lowest common denominator
(FMEA).
Fred, your friend's observations on potential for
ADDED risk by stacking band-aid-on-top-of-band-aid
are germane to what happened on this airplane . . .
combined with poor craftsmanship and understanding
how the various components worked, individually or together.
If any List members become aware of an accident that involves
poor selection or application of electrical system
components, I'd be pleased to add them to this new
library on AeroElectric.com
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: AeroElectric-List Digest: 27 Msgs - 10/24/13 |
At 07:38 AM 10/25/2013, you wrote:
>Does anyone know where I can get a schematic of the internal wiring
>of a TCM Bendix mag/starter switch (BDX 10-357200-1) ?
>Thanks - Jay Bannister
>
Don't know about that particular product but if it's a
classic off-l-r-both-start switch, then it's 99% sure to
be set up like this
Emacs!
Bob . . .
________________________________________________________________________________
| From: | Matt Dralle <dralle(at)matronics.com> |
| Subject: | New Alternator, New Whine... |
Dear Listers,
I just finished the Conditional Inspection on the RV-6. The day after I got everything
buttoned up and went out for a test flight, the alternator started to
flake. The old alternator was some no-name brand thing the original builder
got from somewhere. It never had enough output to power up everything during
taxi and landing. I suspect that it was probably a 40amp unit but there are no
markings on it so I don't know for sure. It had an external regulator; one
of those GM-style, two-wire gems.
So, I replaced it with a brand new PlanePower 60amp internally regulated and OVP'd
unit. The same one, in fact that I have on the RV-8. The good news is that
it really kicks butt and puts out plenty of power even at idle to keeps everything
powered up and the voltage level around 13v (max current draw is about
36amps, so the new alternator has plenty of headroom). With the lights off,
or at higher power settings it puts out a nice solid 14.1 volts or more. I'm
super happy.
Now the bad news. Now I have a loud alternator whine in the headphones! It's
particularly noticeable around 800-1100 RPM. The interesting thing about it is
that adjusting the volume of the Intercom, the Nav/Com, or the Stereo has no
impact of the volume of the whine. Only adjusting the two volumes (L+R) on the
Bose A20 headset dongle will change the volume level of the whine. That seems
like its the Bose that not liking the noise, but...? In the RV-8, I had the
exact same alternator, VP-200, Intercom, stereo, etc. with NO alternator whine.
However, I didn't buy the Bose A20 headsets until after I got the RV-6,
so I never used them in the RV-8. The RV-8 I had the previous model of headset,
the Bose X. I'm going to give the Bose X headphones a try in the RV-6 and
see if I hear the whine.
The A20's are much better headphones than the X's, so I really want to keep using
them, but that whine is pretty insidious. I worry that I may have the same
issue using the A20's in the RV-8 when I get it flying again.
I've been really careful, particularly in the RV-8, to run separate grounds to
everything and not use the airframe as a ground. In the RV-6, since it was already
built, I had less opportunity to do that. However, on the instrument panel,
since I rebuilt that from scratch, most everything electronic got its own
ground to the new grounding tree. Maybe I need to run a ground wire out to the
alternator?
Any insight you can lend would be most appreciated.
-
Matt Dralle
RV-8 #82880 N998RV "Ruby Vixen"
http://www.mattsrv8.com - Matt's Complete RV-8 Construction Log
http://www.mattsrv8.com/Mishap - Landing Mishap Rebuild Log
http://www.youtube.com/MattsRV8 - Matt's RV-8 HDTV YouTube Channel
Status: 172+ Hours TTSN - Rebuilding Fuselage After Landing Mishap...
RV-6 #20916 N360EM "The Flyer"
http://www.mattsrv6.com - Matt's RV-6 Revitalization Log
Status: 180+ Hours Since Purchase - Upgrades Complete; Now In Full Flyer Mode
Matt's Livermore Airport Live ATC Stream!
Check out the live ATC stream directly from my hangar at the Livermore
Airport. Includes both Tower and Ground transmissions. Archives too!
For entertainment purposes only. http://klvk.matronics.com
________________________________________________________________________________
| From: | Jeff Luckey <jluckey(at)pacbell.net> |
| Subject: | Re: Electrically driven accidents |
Hey Bob,=0A=0AWhen I try to view the 01 Fuse vs Breaker.wmv, my media playe
r, Windows Media Player in XP, the video plays for a couple of seconds then
stops & complains that the file is corrupt.- I've downloaded twice.- I
s anyone else having similar probs or is it my media player?=0A=0A-Jeff=0A
=0A=0A=0A=0A________________________________=0A From: "Robert L. Nuckolls,
III" =0ATo: aeroelectric-list(at)matronics.com
=0ASent: Friday, October 25, 2013 7:03 AM=0ASubject: AeroElectric-List: Ele
ctrically driven accidents=0A =0A=0A--> AeroElectric-List message posted by
: "Robert L. Nuckolls, III" =0A=0AI have rec
eived the blessings of my client for conversion=0Aof some- aircraft accid
ent investigation work-product into=0Ateaching tools. Tools that illustrate
the "Been there, done=0Athat, let's don't do it again" sort of teaching.
=0A=0AI've cherry picked the items I produced and published=0Athem in the N
811HB directory on my website under=0A"Accidents."=0A=0Ahttp://tinyurl.com/
ky7szec=0A=0AThe videos were crafted to give a gaggle of attorneys=0Asome b
ackground of the technical issues with the idea=0Athat material would be ta
ilored and re-assembled=0Ainto work-product suited to show to a jury. The c
ase=0Asettled so the draft videos were never superceded.=0AHence the medioc
re production values.=0A=0AThere's a narrative of the accident as published
by=0Athe NTSB, a series of videos that explore a portion=0Aof the electric
al system dedicated to supplying=0Apower to the ignition systems and one pi
cture that=0Aillustrates the manner in which a Dual-Feed, Ignition=0APower
Bus was implemented in this airplane.=0A=0ASeveral of the videos speak to t
he value for=0Afollowing instructions along with risk for failure to=0Aredu
ce a system to the simplest, lowest common denominator=0A(FMEA).=0A=0AFred,
your friend's observations on potential for=0AADDED risk by stacking band-
aid-on-top-of-band-aid=0Aare germane to what happened on this airplane . .
.=0Acombined with poor craftsmanship and understanding=0Ahow the various co
mponents worked, individually or together.=0A=0AIf any List members become
aware of an accident that involves=0Apoor selection or application of elect
rical system=0Acomponents, I'd be pleased to add them to this new=0Alibrary
===========
________________________________________________________________________________
| From: | "David Lloyd" <skywagon(at)charter.net> |
| Subject: | Re: New Alternator, New Whine... |
Matt,
Best guess is that the higher current alt. is insufficiently grounded and is
radiating via its current ground. For a test, I would fire up the RV to the
engine rpm that causes the worst phone noise and then, start shutting down
electrical loads reducing alt. current output. If the noise also
diminishes, then, I would install a better grd. buss to the alt.
Dave
_____________________________________________________________
----- Original Message -----
From: "Matt Dralle" <dralle(at)matronics.com>
Sent: Friday, October 25, 2013 8:47 AM
Subject: AeroElectric-List: New Alternator, New Whine...
>
>
>
> Dear Listers,
>
> I just finished the Conditional Inspection on the RV-6. The day after I
> got everything buttoned up and went out for a test flight, the alternator
> started to flake. The old alternator was some no-name brand thing the
> original builder got from somewhere. It never had enough output to power
> up everything during taxi and landing. I suspect that it was probably a
> 40amp unit but there are no markings on it so I don't know for sure. It
> had an external regulator; one of those GM-style, two-wire gems.
>
> So, I replaced it with a brand new PlanePower 60amp internally regulated
> and OVP'd unit. The same one, in fact that I have on the RV-8. The good
> news is that it really kicks butt and puts out plenty of power even at
> idle to keeps everything powered up and the voltage level around 13v (max
> current draw is about 36amps, so the new alternator has plenty of
> headroom). With the lights off, or at higher power settings it puts out a
> nice solid 14.1 volts or more. I'm super happy.
>
> Now the bad news. Now I have a loud alternator whine in the headphones!
> It's particularly noticeable around 800-1100 RPM. The interesting thing
> about it is that adjusting the volume of the Intercom, the Nav/Com, or the
> Stereo has no impact of the volume of the whine. Only adjusting the two
> volumes (L+R) on the Bose A20 headset dongle will change the volume level
> of the whine. That seems like its the Bose that not liking the noise,
> but...? In the RV-8, I had the exact same alternator, VP-200, Intercom,
> stereo, etc. with NO alternator whine. However, I didn't buy the Bose A20
> headsets until after I got the RV-6, so I never used them in the RV-8.
> The RV-8 I had the previous model of headset, the Bose X. I'm going to
> give the Bose X headphones a try in the RV-6 and see if I hear the whine.
>
> The A20's are much better headphones than the X's, so I really want to
> keep using them, but that whine is pretty insidious. I worry that I may
> have the same issue using the A20's in the RV-8 when I get it flying
> again.
>
> I've been really careful, particularly in the RV-8, to run separate
> grounds to everything and not use the airframe as a ground. In the RV-6,
> since it was already built, I had less opportunity to do that. However,
> on the instrument panel, since I rebuilt that from scratch, most
> everything electronic got its own ground to the new grounding tree. Maybe
> I need to run a ground wire out to the alternator?
>
> Any insight you can lend would be most appreciated.
>
>
> -
> Matt Dralle
>
> RV-8 #82880 N998RV "Ruby Vixen"
> http://www.mattsrv8.com - Matt's Complete RV-8 Construction Log
> http://www.mattsrv8.com/Mishap - Landing Mishap Rebuild Log
> http://www.youtube.com/MattsRV8 - Matt's RV-8 HDTV YouTube Channel
> Status: 172+ Hours TTSN - Rebuilding Fuselage After Landing Mishap...
>
> RV-6 #20916 N360EM "The Flyer"
> http://www.mattsrv6.com - Matt's RV-6 Revitalization Log
> Status: 180+ Hours Since Purchase - Upgrades Complete; Now In Full Flyer
> Mode
>
> Matt's Livermore Airport Live ATC Stream!
> Check out the live ATC stream directly from my hangar at the Livermore
> Airport. Includes both Tower and Ground transmissions. Archives too!
> For entertainment purposes only. http://klvk.matronics.com
>
>
>
________________________________________________________________________________
| From: | Dave Saylor <dave.saylor.aircrafters(at)gmail.com> |
| Subject: | Re: New Alternator, New Whine... |
I've had a similar whine with a PP alternator and Zulu headsets. Same fix,
I slide the L&R volumes down to about mid and adjust everything else to
fit--the whine is much less. I've tried grounding the alternator case
without success. The whine gets louder with more output from the
alternator. I'm all ears, but the fact is I've learned to live with it.
Dave Saylor
831-750-0284 CL
On Fri, Oct 25, 2013 at 10:16 AM, David Lloyd wrote:
> skywagon(at)charter.net>
>
> Matt,
> Best guess is that the higher current alt. is insufficiently grounded and
> is radiating via its current ground. For a test, I would fire up the RV to
> the engine rpm that causes the worst phone noise and then, start shutting
> down electrical loads reducing alt. current output. If the noise also
> diminishes, then, I would install a better grd. buss to the alt.
> Dave
>
> ______________________________**______________________________**_
>
> ----- Original Message ----- From: "Matt Dralle" <dralle(at)matronics.com>
> To: >
> Sent: Friday, October 25, 2013 8:47 AM
> Subject: AeroElectric-List: New Alternator, New Whine...
>
>
>> dralle(at)matronics.com>
>>
>>
>> Dear Listers,
>>
>> I just finished the Conditional Inspection on the RV-6. The day after I
>> got everything buttoned up and went out for a test flight, the alternator
>> started to flake. The old alternator was some no-name brand thing the
>> original builder got from somewhere. It never had enough output to power
>> up everything during taxi and landing. I suspect that it was probably a
>> 40amp unit but there are no markings on it so I don't know for sure. It
>> had an external regulator; one of those GM-style, two-wire gems.
>>
>> So, I replaced it with a brand new PlanePower 60amp internally regulated
>> and OVP'd unit. The same one, in fact that I have on the RV-8. The good
>> news is that it really kicks butt and puts out plenty of power even at idle
>> to keeps everything powered up and the voltage level around 13v (max
>> current draw is about 36amps, so the new alternator has plenty of
>> headroom). With the lights off, or at higher power settings it puts out a
>> nice solid 14.1 volts or more. I'm super happy.
>>
>> Now the bad news. Now I have a loud alternator whine in the headphones!
>> It's particularly noticeable around 800-1100 RPM. The interesting thing
>> about it is that adjusting the volume of the Intercom, the Nav/Com, or the
>> Stereo has no impact of the volume of the whine. Only adjusting the two
>> volumes (L+R) on the Bose A20 headset dongle will change the volume level
>> of the whine. That seems like its the Bose that not liking the noise,
>> but...? In the RV-8, I had the exact same alternator, VP-200, Intercom,
>> stereo, etc. with NO alternator whine. However, I didn't buy the Bose A20
>> headsets until after I got the RV-6, so I never used them in the RV-8. The
>> RV-8 I had the previous model of headset, the Bose X. I'm going to give
>> the Bose X headphones a try in the RV-6 and see if I hear the whine.
>>
>> The A20's are much better headphones than the X's, so I really want to
>> keep using them, but that whine is pretty insidious. I worry that I may
>> have the same issue using the A20's in the RV-8 when I get it flying again.
>>
>> I've been really careful, particularly in the RV-8, to run separate
>> grounds to everything and not use the airframe as a ground. In the RV-6,
>> since it was already built, I had less opportunity to do that. However, on
>> the instrument panel, since I rebuilt that from scratch, most everything
>> electronic got its own ground to the new grounding tree. Maybe I need to
>> run a ground wire out to the alternator?
>>
>> Any insight you can lend would be most appreciated.
>>
>>
>> -
>> Matt Dralle
>>
>> RV-8 #82880 N998RV "Ruby Vixen"
>> http://www.mattsrv8.com - Matt's Complete RV-8 Construction Log
>> http://www.mattsrv8.com/Mishap - Landing Mishap Rebuild Log
>> http://www.youtube.com/**MattsRV8 -
>> Matt's RV-8 HDTV YouTube Channel
>> Status: 172+ Hours TTSN - Rebuilding Fuselage After Landing Mishap...
>>
>> RV-6 #20916 N360EM "The Flyer"
>> http://www.mattsrv6.com - Matt's RV-6 Revitalization Log
>> Status: 180+ Hours Since Purchase - Upgrades Complete; Now In Full Flyer
>> Mode
>>
>> Matt's Livermore Airport Live ATC Stream!
>> Check out the live ATC stream directly from my hangar at the Livermore
>> Airport. Includes both Tower and Ground transmissions. Archives too!
>> For entertainment purposes only. http://klvk.matronics.com
>>
>>
>>
>>
>>
>>
>>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Electrically driven accidents |
At 11:14 AM 10/25/2013, you wrote:
Hey Bob,
When I try to view the 01 Fuse vs Breaker.wmv, my media player,
Windows Media Player in XP, the video plays for a couple of seconds
then stops & complains that the file is corrupt. I've downloaded
twice. Is anyone else having similar probs or is it my media player?
I am mystified. The ByteCount for file on the website
and my desktop are the same but when I downloaded from
the website, the captured file was shorter.
The source file plays fine . . . I reloaded it to
the site and downloaded for a check-run. Seems
to be okay now.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: New Alternator, New Whine... |
Now the bad news. Now I have a loud alternator
whine in the headphones! It's particularly
noticeable around 800-1100 RPM. The interesting
thing about it is that adjusting the volume of
the Intercom, the Nav/Com, or the Stereo has no
impact of the volume of the whine. Only
adjusting the two volumes (L+R) on the Bose A20
headset dongle will change the volume level of
the whine. That seems like its the Bose that
not liking the noise, but...? In the RV-8, I
had the exact same alternator, VP-200, Intercom,
stereo, etc. with NO alternator whine. However,
I didn't buy the Bose A20 headsets until after I
got the RV-6, so I never used them in the RV-8.
The RV-8 I had the previous model of headset, the
Bose X. I'm going to give the Bose X headphones
a try in the RV-6 and see if I hear the whine.
These symptoms scream (or should I say whine?) GROUND LOOP!
I've been really careful, particularly in the
RV-8, to run separate grounds to everything and
not use the airframe as a ground. In the RV-6,
since it was already built, I had less
opportunity to do that. However, on the
instrument panel, since I rebuilt that from
scratch, most everything electronic got its own
ground to the new grounding tree. Maybe I need
to run a ground wire out to the alternator?
I'd check to see that ALL grounds to the Bose system,
audio AND power(-) are grounded at the same place
power(-) and audio for the intercom are grounded.
Your 60A alternator isn't bad and probably isn't
installed wrong . . . it's just capable of putting
more noise into the loop that existed before the
alternator was replaced.
The single point ground concept is often mis-understood
to mean signal grounds only. Given that many if not most
pieces of avionics have an internal common chassis ground
for both signal and ground, you need to treat power grounds
the same as signal grounds.
Do you have a dedicated black-box ground on the
instrument panel or does everything go to a firewall
block? If so, your two points of ground on the airframe
are chassis grounds on the panel and wired grounds
on the firewall.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Electrically driven accidents |
| From: | Peter Pengilly <peter(at)sportingaero.com> |
Try vlc media player?
http://www.videolan.org/vlc/index.html
On Oct 25, 2013 8:23 PM, "Robert L. Nuckolls, III" <
nuckolls.bob(at)aeroelectric.com> wrote:
> nuckolls.bob(at)aeroelectric.com**>
>
>
> At 11:14 AM 10/25/2013, you wrote:
> Hey Bob,
>
> When I try to view the 01 Fuse vs Breaker.wmv, my media player, Windows
> Media Player in XP, the video plays for a couple of seconds then stops &
> complains that the file is corrupt. I've downloaded twice. Is anyone else
> having similar probs or is it my media player?
>
> I am mystified. The ByteCount for file on the website
> and my desktop are the same but when I downloaded from
> the website, the captured file was shorter.
>
> The source file plays fine . . . I reloaded it to
> the site and downloaded for a check-run. Seems
> to be okay now.
>
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | Jeff Luckey <jluckey(at)pacbell.net> |
| Subject: | Re: Electrically driven accidents |
Got it.- =0A=0A=0A2 data points:=0A1. the original file you had up earlie
r today was about 64 MB.- This new one is about 49 MB.=0A2. the download
g. This AM it took <5 min, this PM took > 30 min.- Probably a server load
issue - just though I'd mention it.=0A=0A=0AThx for fixing quickly,=0A=0A-
Jeff=0A=0A=0A=0A=0A________________________________=0A From: "Robert L. Nuc
kolls, III" =0ATo: aeroelectric-list@matroni
cs.com =0ASent: Friday, October 25, 2013 12:06 PM=0ASubject: Re: AeroElectr
ic-List: Electrically driven accidents=0A =0A=0A--> AeroElectric-List messa
ge posted by: "Robert L. Nuckolls, III" =0A
=0A=0AAt 11:14 AM 10/25/2013, you wrote:=0AHey Bob,=0A=0AWhen I try to view
the 01 Fuse vs Breaker.wmv, my media player, Windows Media Player in XP, t
he video plays for a couple of seconds then stops & complains that the file
is corrupt.- I've downloaded twice.- Is anyone else having similar pro
bs or is it my media player?=0A=0A- I am mystified. The ByteCount for fil
e on the website=0A- and my desktop are the same but when I downloaded fr
om=0A- the website, the captured file was shorter.=0A=0A- The source fi
le plays fine . . . I reloaded it to=0A- the site and downloaded for a ch
=================
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Electrically driven accidents |
At 03:30 PM 10/25/2013, you wrote:
>Got it.
>
>2 data points:
>1. the original file you had up earlier today was about 64 MB. This
>new one is about 49 MB.
>the download this morning. This AM it took <5 min, this PM took > 30
>min. Probably a server load issue - just though I'd mention it.
>
>Thx for fixing quickly,
The second upload had been processed for lower
bitrate to make it load better. Thanks for the
feedback!
Bob . . .
________________________________________________________________________________
| Subject: | Re: Alternator without a Battery |
| From: | Thomas E Blejwas <tomblejwas(at)yahoo.com> |
Yes, I accept the mission - I'm responsible for the safety of my aircraft and I
see potential benefits in having the ability to disconnect the batteries. Unfortunately,
my last formal education in electronics was a freshman physics class
many, many years ago. To fill some of the void, I read the AeroElectric Connection,
but sometimes struggle with cognition and retention. I'm counting
on Bob and others on the list for critical evaluation.
I see risks in 3 areas: physical risk associated with the actual operation of
the alternator without a battery, i.e., damage to the alternator itself or other
components; risks associated with circuitry changes to allow for operation
without a battery; and risks in operational changes, i.e., people engineering
or cockpit management. I'll leave the first of these to last, because I feel
least confident with my understanding.
Since the batteries (I'm planning on 2 in my system) are no longer "always on,"
they are logically each connected through a contactor or other type of switch.
I won't rehash the recent discussions of contactors, but with two batteries
and contactors, the risk of contactor failure is small compared to the additional
redundancy (assuming operational recognition and response) of an alternator
without a battery. For my system, the steady-state load will be on the order
of 15 amps, which shouldn't overly challenge a traditional style contactor,
e.g., from B&C. Although I need to design and evaluate the entire electrical
system, I don't see any other inherent circuitry changes. My basic approach
is a ocircuit to which the batteries and alternator may or may not be connected.
The buses may be physically connected to the circuit near a particular power
source, but the primary purpose of multiple buses is to allow critical redundant
devices (primarily fuel pumps and ECUs) to be connected in such a way that
the loss of a single connection will not cause loss of power or, at worst,
can be recovered by one or two switches.
With the potential for one battery to be disconnected in "normal flight," operations
need to be established to ensure both batteries are charged and available.
This could be as simple as connecting both into the charging circuit, but
then power is being drawn from both and neither is a traditional "backup." My
preference is for one to be connected for one leg of a trip and the other for
the return or next leg. This works particularly well if I choose to use lithium
phosphate batteries, because their unused discharge rate is extremely low.
(I'm periodically checking online for fires with Shorai batteries, because these
are widely used on motorcycles. So far, mishaps are few and not explosive.
Also, one of the areas under my purview in a past position was a battery destructive-test
lab. I'll be trying to get non-proprietary info from the people
at this lab.) I also think it is prudent to monitor each battery during flight
with instruments like the MGL BAT-1, which provide both voltage and current.
If the engine stops in flight, I don't want to have to remember how the electrical
system works to recover. If no electrical power, check the battery monitors
and change contactors to the unused one. If there is electrical power, switch
fuel pumps and switch ECU power source (both changing to a different bus and
associated connections) and finally switch to backup ECU. For me this is simpler
than determining what to switch at the top of Z-19, but that probably just
shows my lack of familiarity with aero-electrical speak. I don't see using
the alternator without a battery except for the following. Monitoring of the
batteries shows a problem with a battery and the other one replaces it. (Or
maybe it is the standby battery with a problem.) Before being able to land,
the second battery starts acting up. Now, switch both off and do a precautionary
landing ASAP.
Now, what about the risks to the alternator or other critical devices because an
alternator is running without a connected battery? First, Viking has claimed
that the alternator can be so run. A capacitor was initially required, which
makes sense in that it would "smooth" the output; but, curiously, engine owners
were later instructed to remove the capacitor. I could find no explanation
for the change and my memory is that an inquiry was ignored. I'll make my
own attempt at finding out why. At this point, I plan to design with the option
and test the output after completion. I can see no harm in having a capacitor
in the circuit, but hopefully others will correct me if I'm wrong.
Sorry if I've missed the point of your suggestion or gone off on too many tangents.
I realize that a schematic would have been helpful for this discussion,
but I'm just starting to teach myself TurboCAD and who knows how long that will
take.
Tom
Sent from my iPad
________________________________________________________________________________
| Subject: | Re: EXP 2 Bus workaround |
| From: | Fred Klein <fklein(at)orcasonline.com> |
Bob, thank you for your analysis and recommendations...they greatly enhance my
learning experience here...please see my indents below...I have additional comments
(later) on your posted circuit diagram of this morning...Fred
On Oct 23, 2013, at 4:41 PM, Robert L. Nuckolls, III wrote:
> Okay, getting closer.
>
> (1) Recommend you take the engine bus normal feedpath directly
> from the main bus through the diode. A normal Engine ON/OFF
> switch in this path seems to make sense see (6).
I don't understand how I might "take the engine bus normal feedpath directly
from the main bus through the diode." It seems to imply to me that I poke around
on the circuit board and find a place to attach a wire. I thought my proposal
to tap the existing two 11 amp AUX circuits with a fast-on spade or two would
be a rather elegant way to use what's available. (See my comments on your item
(6) below.)
> (2) add 30A maxi fuse in series with Engine Bus Alternate
> Feed path and being engine power forward on 10AWG wire.
OK...straightforward enough...
>
> (3) Take E-Bus alternate feed directly from the battery on
> it's own 7A fuse and 14AWG wire . . . 10A fuse if determined
> necessary later.
I can do that; this adds another wire forward from rear battery to bus...What's
the advantage of doing this rather than using a short wire to the Engine (MP)
bus, as long as the total E-bus + MP bus loads can be handled by the EXP Bus
circuit from which power is being drawn? Normally (I believe the) E-bus alternate
feed will ONLY be activated in conjunction w/ the Engine (MP) bus alternate
feed (sized accordingly) is activated.
> (4) Go to solid state relays for e-bus and E-bus alternate
> feeds, either Eric's or ours.
OK
> (5) Run #2 fuel pump from main bus through polyfuse and
> EXP Bus switch.
Let's talk about the 2 fuel pumps for a MPEFI engine. Unlike w/ carb engines,
the 2nd pump is not used as a boost pump. I'm advised that w/ a MPEFI engine,
one never wants to run more than ONE pump at a time due to excessive pressure
in the system.
This is why I've been showing 2 switches in series...the first switch powers
up a single fuel pump...whether that is pump #1 or pump #2 depends on the second
switch. The reason for two fuel pumps is to ensure fuel flow in the event of
either a pump failure or a clogged filter. These events can occur regardless
of where the elec power is coming from. I say it's essential that BOTH pumps
can be energized either thru the EXP Bus or the Engine (MP) bus alternate feed.
I believe your point (5) misconstrues the purpose of dual pumps in a MPEFI engine.
What am I missing?
> (6) I see no value in having separate switches for
> injectors, coils, normal pump or ECU feed. One switch
> in normal feed path for normal engine ops, one switch
> to control alternate feed path. When and why would you
> ever operate one of these switches independently of
> the others. Two ways to power engine . . . normal and
> alternate.
On reflection, I understand (finally)...a single switch it is.
>
> (7) Suggest separate fuses for each injector and coil
> assuming engine produces some useable power with any
> one fuse open.
This sounds like a novel idea...I'm wondering if anyone's ever done this before?..
how much increased complexity is entailed?...and whether or not historical
rates of injector and coil failures suggest that this would be prudent?
> (8) Starter can control from main bus.
True...and...w/ my particular combination of engine, reduction ratio, propeller,
and aircraft performance envelope, although I THINK that with engine out,
prop would windmill sufficient to restart engine, if Master switch was OFF, I'd
like to be able to spin the starter...that was the INTENT of what the diagram
shows...What do you think?...I'm unsure as to whether or not the wiring diagram
allows for that to happen.
> (9) Turn existing avionics bus into e-bus, convert
> old avionics master into alternate feed path control
> switch. Normal feed path comes from main bus through
> diode.
I'm completely in the dark as to my understanding of what physical changes must
be made to the EXP Bus to accomplish this.
>
> (10) You speak to "room for breakers/fuses on panel"
> suggest these be out of sight, of reach.
That would be possible of course, though if CBs are used, questionable. I'm presuming
that you want them out of sight to reduce workload in an emergency, and
to avoid possibly exacerbating conditions by resetting popped CBs...is that
so?
>
>
>
>
> Bob . . .
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 07:35 PM 10/25/2013, you wrote:
>
>Bob, thank you for your analysis and recommendations...they greatly
>enhance my learning experience here...please see my indents
>below...I have additional comments (later) on your posted circuit
>diagram of this morning...Fred
We're getting the cart out in front. Let's get a 98%
golden list of electro-whizzies and where they'll
get powered.
The Z-08 drawing is just architecture for now, the mechanism
by which an EXP-Bus duplicates or emulates the philosophy
is a separate task.
> >
> > (3) Take E-Bus alternate feed directly from the battery on
> > it's own 7A fuse and 14AWG wire . . . 10A fuse if determined
> > necessary later.
>
> I can do that; this adds another wire forward from
> rear battery to bus...What's the advantage of doing this rather
> than using a short wire to the Engine (MP) bus, as long as the
> total E-bus + MP bus loads can be handled by the EXP Bus circuit
> from which power is being drawn? Normally (I believe the) E-bus
> alternate feed will ONLY be activated in conjunction w/ the Engine
> (MP) bus alternate feed (sized accordingly) is activated.
We can thrash this detail later . . .
> Let's talk about the 2 fuel pumps for a MPEFI
> engine. Unlike w/ carb engines, the 2nd pump is not used as a boost
> pump. I'm advised that w/ a MPEFI engine, one never wants to run
> more than ONE pump at a time due to excessive pressure in the system.
How does this happen? I understand that there's a pressure
regulator downstream of the pump outputs. Paralleling two
active pumps only increases potential for flow . . . like
hooking two batteries in parallel.
> > (7) Suggest separate fuses for each injector and coil
> > assuming engine produces some useable power with any
> > one fuse open.
>
> This sounds like a novel idea...I'm wondering
> if anyone's ever done this before?.. how much increased complexity
> is entailed?...and whether or not historical rates of injector and
> coil failures suggest that this would be prudent?
I've seen this before. The idea is that no single failure
takes out all injectors and an engine will produce useful
power with one injector down.
> > (8) Starter can control from main bus.
>
> True...and...w/ my particular combination of
> engine, reduction ratio, propeller, and aircraft performance
> envelope, although I THINK that with engine out, prop would
> windmill sufficient to restart engine, if Master switch was OFF,
> I'd like to be able to spin the starter...that was the INTENT of
> what the diagram shows...What do you think?...I'm unsure as to
> whether or not the wiring diagram allows for that to happen.
Is anyone flying this combination of hardware? How much does
IAS need to be reduced to stop a windmilling prop? The few
times I stopped the prop on a TC airplane I had to really
work at it. The idea that one needs access to a starter
motor in flight is mostly without foundation. This is a
fact you need to resolve for your harware combination.
> > (9) Turn existing avionics bus into e-bus, convert
> > old avionics master into alternate feed path control
> > switch. Normal feed path comes from main bus through
> > diode.
>
> I'm completely in the dark as to my understanding
> of what physical changes must be made to the EXP Bus to accomplish this.
Later . . . I don't think it's going to be difficult.
> >
> > (10) You speak to "room for breakers/fuses on panel"
> > suggest these be out of sight, of reach.
>
> That would be possible of course, though if CBs are
> used, questionable. I'm presuming that you want them out of sight
> to reduce workload in an emergency, and to avoid possibly
> exacerbating conditions by resetting popped CBs...is that so?
The only time a fuse or breaker opens is because something
is broke (which means new fuse doesn't help) or the circuit
protection is undersized (nuisance trip - which on an OBAM
aircraft gets fixed). Hence, no value for being able to see/reach
breakers and fuses.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: Alternator without a Battery |
At 06:29 PM 10/25/2013, you wrote:
>
>
>Yes, I accept the mission - I'm responsible for the safety of my
>aircraft and I see potential benefits in having the ability to
>disconnect the batteries. Unfortunately, my last formal education
>in electronics was a freshman physics class many, many years
>ago. To fill some of the void, I read the AeroElectric Connection,
>but sometimes struggle with cognition and retention. I'm counting
>on Bob and others on the list for critical evaluation.
The only time I think one deliberately shuts off batteries
in flight is for smoke in the cockpit . . . which means
alternator needs to be off too.
>I see risks in 3 areas: physical risk associated with the actual
>operation of the alternator without a battery, i.e., damage to the
>alternator itself or other components; risks associated with
>circuitry changes to allow for operation without a battery; and
>risks in operational changes, i.e., people engineering or cockpit
>management. I'll leave the first of these to last, because I feel
>least confident with my understanding.
Many alternators run fine without a battery. They may
not start but once in operation, they produce useful energy
with a disconnected battery. Bonanzas and Barons have offered
this feature for decades.
>Since the batteries (I'm planning on 2 in my system) are no longer
>"always on," they are logically each connected through a contactor
>or other type of switch.
Why two batteries?
> I won't rehash the recent discussions of contactors, but with two
> batteries and contactors, the risk of contactor failure is small
> compared to the additional redundancy (assuming operational
> recognition and response) of an alternator without a battery. For
> my system, the steady-state load will be on the order of 15 amps,
> which shouldn't overly challenge a traditional style contactor,
> e.g., from B&C. Although I need to design and evaluate the entire
> electrical system, I don't see any other inherent circuitry
> changes. My basic approach is a ocircuit to which the batteries
> and alternator may or may not be connected. The buses may be
> physically connected to the circuit near a particular power source,
> but the primary purpose of multiple buses is to allow critical
> redundant devices (primarily fuel pumps and ECUs) to be connected
> in such a way that the loss of a single connection will not cause
> loss of power or, at worst, can be recovered by one or two switches.
Have you been following the thread on Fred's project?
Check the drawings I published earlier today and assess
potential for missing your design goals. The question is,
suppose a contactor DOES fail, how does that impact risks
for comfortable termination of flight?
Bob . . .
________________________________________________________________________________
| From: | John W Livingston <livingjw(at)earthlink.net> |
| Subject: | Re: EXP 2 Bus workaround |
I am still stumped as to why you would recommend one battery. I could
agree if the one alternator is guaranteed to work without the battery in
the circuit, but not without that backup. You must think batteries are
much more reliable than I do.
John
On 10/25/2013 10:42 PM, Robert L. Nuckolls, III wrote:
> At 07:35 PM 10/25/2013, you wrote:
>>
>>
>> Bob, thank you for your analysis and recommendations...they greatly
>> enhance my learning experience here...please see my indents below...I
>> have additional comments (later) on your posted circuit diagram of
>> this morning...Fred
>
> * We're getting the cart out in front. Let's get a 98%
> golden list of electro-whizzies and where they'll
> get powered.
>
> The Z-08 drawing is just architecture for now, the mechanism
> by which an EXP-Bus duplicates or emulates the philosophy
> is a separate task.
>
> *
>> >
>> > (3) Take E-Bus alternate feed directly from the battery on
>> > it's own 7A fuse and 14AWG wire . . . 10A fuse if determined
>> > necessary later.
>>
>> I can do that; this adds another wire forward from rear battery to
>> bus...What's the advantage of doing this rather than using a short
>> wire to the Engine (MP) bus, as long as the total E-bus + MP bus
>> loads can be handled by the EXP Bus circuit from which power is being
>> drawn? Normally (I believe the) E-bus alternate feed will ONLY be
>> activated in conjunction w/ the Engine (MP) bus alternate feed (sized
>> accordingly) is activated.
>
> * We can thrash this detail later . . .
>
>
> *
>> Let's talk about the 2 fuel pumps for a MPEFI engine. Unlike w/ carb
>> engines, the 2nd pump is not used as a boost pump. I'm advised that
>> w/ a MPEFI engine, one never wants to run more than ONE pump at a
>> time due to excessive pressure in the system.
>
> * How does this happen? I understand that there's a pressure
> regulator downstream of the pump outputs. Paralleling two
> active pumps only increases potential for flow . . . like
> hooking two batteries in parallel.
>
> *
>> > (7) Suggest separate fuses for each injector and coil
>> > assuming engine produces some useable power with any
>> > one fuse open.
>>
>> This sounds like a novel idea...I'm wondering if anyone's ever done
>> this before?.. how much increased complexity is entailed?...and
>> whether or not historical rates of injector and coil failures suggest
>> that this would be prudent?
>
> * I've seen this before. The idea is that no single failure
> takes out all injectors and an engine will produce useful
> power with one injector down.
>
>
> *
>> > (8) Starter can control from main bus.
>>
>> True...and...w/ my particular combination of engine, reduction ratio,
>> propeller, and aircraft performance envelope, although I THINK that
>> with engine out, prop would windmill sufficient to restart engine, if
>> Master switch was OFF, I'd like to be able to spin the starter...that
>> was the INTENT of what the diagram shows...What do you think?...I'm
>> unsure as to whether or not the wiring diagram allows for that to happen.
>
> * Is anyone flying this combination of hardware? How much does
> IAS need to be reduced to stop a windmilling prop? The few
> times I stopped the prop on a TC airplane I had to really
> work at it. The idea that one needs access to a starter
> motor in flight is mostly without foundation. This is a
> fact you need to resolve for your harware combination.
>
>
> *
>> > (9) Turn existing avionics bus into e-bus, convert
>> > old avionics master into alternate feed path control
>> > switch. Normal feed path comes from main bus through
>> > diode.
>>
>> I'm completely in the dark as to my understanding of what physical
>> changes must be made to the EXP Bus to accomplish this.
>
> * Later . . . I don't think it's going to be difficult.
>
> *
>> >
>> > (10) You speak to "room for breakers/fuses on panel"
>> > suggest these be out of sight, of reach.
>>
>> That would be possible of course, though if CBs are used,
>> questionable. I'm presuming that you want them out of sight to reduce
>> workload in an emergency, and to avoid possibly exacerbating
>> conditions by resetting popped CBs...is that so?
>
> * The only time a fuse or breaker opens is because something
> is broke (which means new fuse doesn't help) or the circuit
> protection is undersized (nuisance trip - which on an OBAM
> aircraft gets fixed). Hence, no value for being able to see/reach
> breakers and fuses.
>
>
> *
>
> Bob . . .
>
> *
>
>
> *
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 25, 2013, at 7:42 PM, Robert L. Nuckolls, III wrote:
>> Let's talk about the 2 fuel pumps for a MPEFI
engine. Unlike w/ carb engines, the 2nd pump is not used as a boost
pump. I'm advised that w/ a MPEFI engine, one never wants to run more
than ONE pump at a time due to excessive pressure in the system.
>
> How does this happen? I understand that there's a pressure
> regulator downstream of the pump outputs. Paralleling two
> active pumps only increases potential for flow . . . like
> hooking two batteries in parallel.
Bob...I get your point about pressure...let me try to
get better info...it may be that restriction due to size of return fuel
line can't accept the increased flow...I'll check back about this.
>> > (8) Starter can control from main bus.
>>
>> True...and...w/ my particular combination of engine,
reduction ratio, propeller, and aircraft performance envelope, although
I THINK that with engine out, prop would windmill sufficient to restart
engine, if Master switch was OFF, I'd like to be able to spin the
starter...that was the INTENT of what the diagram shows...What do you
think?...I'm unsure as to whether or not the wiring diagram allows for
that to happen.
>
> Is anyone flying this combination of hardware? How much does
> IAS need to be reduced to stop a windmilling prop? The few
> times I stopped the prop on a TC airplane I had to really
> work at it. The idea that one needs access to a starter
> motor in flight is mostly without foundation. This is a
> fact you need to resolve for your harware combination.
Bob...I'm getting some data on this.
Fred
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 25, 2013, at 6:32 AM, Robert L. Nuckolls, III wrote:
> Attached are the preliminary sketches for my current
> thoughts on an architecture for single battery, single
> alternator, electrically dependent engine. This line of
> thinking is being developed as an preferred alternative
> to Z-19.
Bob...I'm delighted that my queries have triggered your
taking a fresh look at Z-19...and presumably, Z-19RB.
>
> This architecture has roots in Z-11 Three-Bus structure
> with the addition of a Motive Power Bus (engine). With
> the term E-bus already in legacy use, the MP-Bus terminology
> offers a stand-out label that avoids confusion.
...perhaps it won't be too long before MP busses will
morph into ones intended for truly all electric power trains...
>
> The major difference is the addition of the MP-bus having
> normal feedpath from the main bus, alternate feedpath from
> the battery . . . same as the E-Bus except BOTH pathways
> have panel mounted switches. The e-bus is always hot any
> time the main bus is hot, but the MP-Bus as power to the
> engine needs to be controlled through both pathways.
>
> I'm thinking that the EXP-bus can be folded into this
> architecture by conversion of battery switch to DC master
> and take alternator field through second pole. Convert
> the 'avionice master' Engine A. Use switch between the
> big red rockers as e-bus alternate feed. Switch to right
> of Engine A is Engine B.
=46rom the get-go, my intent has been to supplement the
capabilities of the EXP Bus to provide for the special requirements for
a MPEFI engine AND to provide the alternate feeds featured in
AeroElectric's Z-xx diagrams in case something goes amiss.
I question your suggestion to:
> Use switch between the big red rockers as e-bus alternate feed. Switch
to right of Engine A is Engine B.
I'm reluctant to interpose within the row of EXP Bus
rockers, switches which would only be used during an emergency.
Conceptually, I much prefer the notion of having a row
of rockers, all of which are used in the course of normal
operations...and a second, distinctly different row of rockers which
will only be used during emergencies.
(The wide, red, Master switch at the left
end...distinctive in both width and color...is of course used both in
normal and emergency ops.)
Organizing the panel in this manner...at least to
me...sets the stage for calm and cool actions when under stress.
I understand your desire for me to proceed w/ listing of
elec loads for all components...a task I recognise as essential...but
first I want to be confident that I understand the big picture. And the
big picture for me is how we supplement the capabilities of the EXP Bus
in order to have the benefits of engine and endurance busses with
alternate feeds from the battery.
Notwithstanding the shortcomings, some poor choices, and
undoubtedly some serious errors, the last diagram I posted (Revision
#XX) did two things of note:
First, it pulls power from the EXP Master Bus for the MP
(engine) bus from 2 - 11 amp circuits, AUX1 and AUX2. (...now I don't
know exactly how those 2 circuits can be combined, but something tells
me there's a way which is simple and direct...)
Second, the Revision XX diagram shows the EXP Avionics
Bus powering the E-bus (endurance) from a 7 amp circuit. (...btw, I
don't understand the notion that we should be rid of the avionics master
switch...). Also...note that w/ Skyview and the back up GPS both having
their own back up batteries, if either the Master switch or the Avionics
Master is turned off and the E-bus Alternate Feed is energized, we'll be
back in business w/ a full suite of avionics.
It strikes me that this approach is elegant, simple, and
direct; I shudder at the thought of altering any part of the circuitry
within the EXP Bus other than changing some Fast-on spades of a couple
of switches and relabeling them.
I'm baffled when you write,
> Old avionics bus becomes e-bus.
...as I look at the circuit board of the EXP Bus, I
haven't a clue how this can happen and create the alternate feed
intrinsic w/ the e-bus concept...way outside my comfort zone to poke
around in that circuit board.
Fred
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: EXP 2 Bus workaround |
FWIW two parallel subaru oem EFI pumps from a 4 cylinder legacy work
fine with a oem regulator all of 1990 to 1994 vintage. Pressure goes up
no more than 2 psi. even with my somewhat restrictive 5/16" return
plumbing. Some fellows run both pumps for landing and takeoff. Selecting
both on is the first thing we do if the engine is not running properly.
Injector flow increases with the square root of pressure so that is not
an issue since normal EFI pressures run around 38 psi above manifold
pressure.
Ken
On 25/10/2013 10:42 PM, Robert L. Nuckolls, III wrote:
> *
> *
>> Let's talk about the 2 fuel pumps for a MPEFI engine. Unlike w/ carb
>> engines, the 2nd pump is not used as a boost pump. I'm advised that w/
>> a MPEFI engine, one never wants to run more than ONE pump at a time
>> due to excessive pressure in the system.
>
> * How does this happen? I understand that there's a pressure
> regulator downstream of the pump outputs. Paralleling two
> active pumps only increases potential for flow . . . like
> hooking two batteries in parallel.*
________________________________________________________________________________
| Subject: | Re: Landing gear warning trigger |
> Yep. You already have a fabricated bracket and two anchor bolts available
> close by. I'd just re-make the existing bracket (or add a new one) to
> extend toward the lever arm and mount a micro switch. You could put an 'L'
> shaped tab on the arm using the existing hole to contact the switch if you
> need to move the assembly inboard to clear the fuel line.
Nope. That's what is typically done. But the routing of my MAP line doesn't allow
for that. I couldn't get a picture showing it, but extending the bracket would
require new fittings and a new MAP line to be fabricated. I'm trying to see
if there's a workaround.
> Or like I mentioned before, mount the switch remotely and activate it with a
slave rod (piano wire) from the lever arm...on either side (push or pull can work).
That's a little more complicated but allows you to work around space limitations
or obstructions if needed.
That's a thought. I'll have to look and see how much trouble that's going to be.
> Simple stuff...bunches of various options. I see no real need for something
complex.
Agreed. That's why I was thinking of a MAP switch that would close when the MAP
got down to around 12-13"
> BTW, I hope this you have already addressed this - that mounting clamp looks
not to be fully secured. You dont want to "pre-disaster" yourself and have the
throttle linkage come loose in flight. Just checking.
I'm a LONG way off from even starting the engine. Let alone moving under it's own
power. When things are tightened/secured, they get some torque seal. Until
then, it's easier to remove for other installations and modifications.
Thanks,
Don
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=411442#411442
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 11:44 PM 10/25/2013, you wrote:
>I am still stumped as to why you would recommend one battery. I
>could agree if the one alternator is guaranteed to work without the
>battery in the circuit, but not without that backup. You must think
>batteries are much more reliable than I do.
Oky, let's ex[;pre that premise. What in your
studies and/or experience with batteries leads
you to believe that they demonstrate a risky,
in-service failure rate?
Before you add a second battery, are there things
that can be done to mitigate your concerns and
reduce in-service failures to acceptable risk
levels?
Recall that the original premise for dual batteries
had nothing to do with worries for battery failure
and everything to do with walling off known quantities
of energy off to do separate tasks . . . where one
of those tasks was critical to continued flight:
keep the engine running. The two battery concept was
never intended to be a hedge against the failure
of one battery.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 01:51 AM 10/26/2013, you wrote:
On Oct 25, 2013, at 6:32 AM, Robert L. Nuckolls, III wrote:
Attached are the preliminary sketches for my current
thoughts on an architecture for single battery, single
alternator, electrically dependent engine. This line of
thinking is being developed as an preferred alternative
to Z-19.
Bob...I'm delighted that my queries have triggered your taking a
fresh look at Z-19...and presumably, Z-19RB.
This architecture has roots in Z-11 Three-Bus structure
with the addition of a Motive Power Bus (engine). With
the term E-bus already in legacy use, the MP-Bus terminology
offers a stand-out label that avoids confusion.
...perhaps it won't be too long before MP busses will morph into ones
intended for truly all electric power trains...
The major difference is the addition of the MP-bus having
normal feedpath from the main bus, alternate feedpath from
the battery . . . same as the E-Bus except BOTH pathways
have panel mounted switches. The e-bus is always hot any
time the main bus is hot, but the MP-Bus as power to the
engine needs to be controlled through both pathways.
I'm thinking that the EXP-bus can be folded into this
architecture by conversion of battery switch to DC master
and take alternator field through second pole. Convert
the 'avionice master' Engine A. Use switch between the
big red rockers as e-bus alternate feed. Switch to right
of Engine A is Engine B.
From the get-go, my intent has been to supplement the capabilities
of the EXP Bus to provide for the special requirements for a MPEFI
engine AND to provide the alternate feeds featured in AeroElectric's
Z-xx diagrams in case something goes amiss.
I question your suggestion to:
Use switch between the big red rockers as e-bus alternate feed.
Switch to right of Engine A is Engine B.
I'm reluctant to interpose within the row of EXP Bus rockers,
switches which would only be used during an emergency.
Conceptually, I much prefer the notion of having a row of rockers,
all of which are used in the course of normal operations...and a
second, distinctly different row of rockers which will only be used
during emergencies.
Please . . . purge the work EMERGENCY from your
thought processes. Things on airplanes break all
the time. If they did not, FBO maintenance shops
would be out of business and Jiffy-Lube could move
into the empty space while adding a wash-rack.
You have Plan-A, everything works in accordance
with the refined constellation of design goals.
Then there is Plan-B, something broke . . . a
condition that has been anticipated in our FEMA
and we're dealing with it under a sub-set of
the original design goals. Then there's Plan-C,
supported by some goodies in the flight bag
that describe yet a smaller sub-set of original
design goals.
An airplane configured artfully conducted FMEA
operating by a pilot who understands the machine's
strengths and weaknesses does not experience
electrical emergencies . . . only events of
in-service failure or wear-out that will need
to be hammered on once you've arrived at your
intended destination.
(The wide, red, Master switch at the left end...distinctive in both
width and color...is of course used both in normal and emergency ops.)
Organizing the panel in this manner...at least to me...sets the stage
for calm and cool actions when under stress.
I understand your desire for me to proceed w/ listing of elec loads
for all components...a task I recognise as essential...but first I
want to be confident that I understand the big picture. And the big
picture for me is how we supplement the capabilities of the EXP Bus
in order to have the benefits of engine and endurance busses with
alternate feeds from the battery.
The BIG picture is that drawing I published.
You're getting distracted by the existence of
the EXP-Bus.
Notwithstanding the shortcomings, some poor choices, and undoubtedly
some serious errors, the last diagram I posted (Revision #XX) did two
things of note:
First, it pulls power from the EXP Master Bus for the MP (engine) bus
from 2 - 11 amp circuits, AUX1 and AUX2. (...now I don't know exactly
how those 2 circuits can be combined, but something tells me there's
a way which is simple and direct...)
Second, the Revision XX diagram shows the EXP Avionics Bus powering
the E-bus (endurance) from a 7 amp circuit. (...btw, I don't
understand the notion that we should be rid of the avionics master
switch...). Also...note that w/ Skyview and the back up GPS both
having their own back up batteries, if either the Master switch or
the Avionics Master is turned off and the E-bus Alternate Feed is
energized, we'll be back in business w/ a full suite of avionics.
The avionics master switch was a flawed idea
from the get-go. I was at Cessna when the thing
was birthed and I've come to understand how
we marched off down that no-value-added
path. See:
http://tinyurl.com/pgcgx9m
It strikes me that this approach is elegant, simple, and direct; I
shudder at the thought of altering any part of the circuitry within
the EXP Bus other than changing some Fast-on spades of a couple of
switches and relabeling them.
Ignore the EXP=Bus for now, we need to
make the architecture work first.
I'm baffled when you write,
"Old avionics bus becomes e-bus."
There is presently an avionics master switch that
controls all power to a chunk of copper glued
to the epoxy-glas that distributes power to terminals
on the board through an array of poly-fuses. This
is your 'avionics' bus which I believe can become
your new e-bus.
...as I look at the circuit board of the EXP Bus, I haven't a clue
how this can happen and create the alternate feed intrinsic w/ the
e-bus concept...way outside my comfort zone to poke around in that
circuit board.
It's just "wires" glued to a piece of epoxy-glas.
Nothing happens on that assembly that a large
number of our contemporaries haven't done with
fuses, wires, breakers and switches. The marketing-hook
for an EXP-Bus is it's relative complexity for stuffing
a lot of activity into a small volume and then offering
it to the customer as, "Here, look at all these things
we did FOR you so that you don't HAVE to."
The question never asked and answered is, "Does that
assembly DO things that people who choose not to
use your product will wish they had included at
some later time?" In other words, what is the
return on investment for you having exchanged your
dollars for their time, talents and resources?
That's what we're doing here right now. The sketches
I published don't speak to how the EXP-Bus will be
'jeeped' (Old television vernacular for modifying
a piece of equipment to some new task not offered
by the designers) into the spirit and intent of
the new Z-figure. Let's assume for the moment that
EXP-Bus is not present. The sketches are not
a "Z-figure for EXP-Buses" . . . it's a new architecture
is a stand alone recipe for success crafted from
rudimentary ingredients. Making a practical
adaptation of an EXP-Bus to the task is a separate
activity we can tackle after the cake is in the oven.
It's just 'frosting' . . .
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 05:51 AM 10/26/2013, you wrote:
>
>FWIW two parallel subaru oem EFI pumps from a 4 cylinder legacy work
>fine with a oem regulator all of 1990 to 1994 vintage. Pressure goes
>up no more than 2 psi. even with my somewhat restrictive 5/16"
>return plumbing. Some fellows run both pumps for landing and
>takeoff. Selecting both on is the first thing we do if the engine is
>not running properly. Injector flow increases with the square root
>of pressure so that is not an issue since normal EFI pressures run
>around 38 psi above manifold pressure.
Good data sir. Thanks!
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
>> Is anyone flying this combination of hardware? How much does
>> IAS need to be reduced to stop a windmilling prop? The few
>> times I stopped the prop on a TC airplane I had to really
>> work at it. The idea that one needs access to a starter
>> motor in flight is mostly without foundation. This is a
>> fact you need to resolve for your harware combination.
>
>Bob...I'm getting some data on this.
Does your engine feature a PSRU? If so, does it
include a spag-clutch on the propeller shaft
for mitigation of rotational vibration stresses
on the gearbox?
If so, then the prop windmills at all speeds and
does not back-drive the engine. But in any case,
pushing a starter button with the notion that a
starter will respond assumer is ales a battery contactor
is closed and FAT-wire power is also available to
the starter. Starter button is not an E-bus load.
Bob . . .
________________________________________________________________________________
| From: | John W Livingston <livingjw(at)earthlink.net> |
| Subject: | Re: EXP 2 Bus workaround |
On this list we have seen examples of internal battery failures and wire
connector failures and switch failures. Granted that these things
typically have low failure rates, but if they happen, you have no
backup. By going with one battery and not knowing if the alternator will
back you up you have elevated these failures to the status of a prop,
engine, wing or control surface failure.
John
On 10/26/2013 9:03 AM, Robert L. Nuckolls, III wrote:
> At 11:44 PM 10/25/2013, you wrote:
>> I am still stumped as to why you would recommend one battery. I could
>> agree if the one alternator is guaranteed to work without the battery
>> in the circuit, but not without that backup. You must think batteries
>> are much more reliable than I do.
>
> Oky, let's ex[;pre that premise. What in your
> studies and/or experience with batteries leads
> you to believe that they demonstrate a risky,
> in-service failure rate?
> Before you add a second battery, are there things
> that can be done to mitigate your concerns and
> reduce in-service failures to acceptable risk
> levels?
>
> Recall that the original premise for dual batteries
> had nothing to do with worries for battery failure
> and everything to do with walling off known quantities
> of energy off to do separate tasks . . . where one
> of those tasks was critical to continued flight:
> keep the engine running. The two battery concept was
> never intended to be a hedge against the failure
> of one battery.
>
> Bob . . .
>
> *
>
>
> *
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 26, 2013, at 3:51 AM, Ken wrote:
> FWIW two parallel subaru oem EFI pumps from a 4 cylinder legacy work
fine with a oem regulator all of 1990 to 1994 vintage. Pressure goes up
no more than 2 psi. even with my somewhat restrictive 5/16" return
plumbing. Some fellows run both pumps for landing and takeoff. Selecting
both on is the first thing we do if the engine is not running properly.
Injector flow increases with the square root of pressure so that is not
an issue since normal EFI pressures run around 38 psi above manifold
pressure.
Thanks Ken...I stand corrected...my engine at 1.8 L is a tad smaller
than your Legacy...it's set up w/ 3/8" fuel supply line and a 1/4"
return line using R9 injector hose aft of my firewall. I believe the
fuel pressure regulator has been set to factor in whatever restrictive
backpressure the 1/4" return line contributes.
Ron Carr at RAM Performance sez my engine's fuel pressure will be 38 psi
at idle and rise to 43 psi at WOT.
(I have not discussed the dual pump issues w/ him because he sells his
engines with only one pump.)
Fred
________________________________________________________________________________
| Subject: | Re: EXP 2 Bus workaround |
| From: | Richard Girard <aslsa.rng(at)gmail.com> |
Fred, Bob, et al, I have no dog in this fight, I've just been following the
discussion but I've got to ask; with all these workarounds you're doing to
make the EXPBus work with your airplane's systems, what is it buying you?
The Spruce description of the EXPBus is all about easy squeazy installation
and time savings, yet you're being forced into more and more redesign and
adaptation in order to make it work for you. I realize that you're a long
way down the road with this thing but have you thought about just grabbing
a clean sheet of paper and sending the EXPBus to eBay?
Rick Girard
On Sat, Oct 26, 2013 at 8:58 AM, John W Livingston
wrote:
> On this list we have seen examples of internal battery failures and wire
> connector failures and switch failures. Granted that these things typically
> have low failure rates, but if they happen, you have no backup. By going
> with one battery and not knowing if the alternator will back you up you
> have elevated these failures to the status of a prop, engine, wing or
> control surface failure.
>
> John
>
>
> On 10/26/2013 9:03 AM, Robert L. Nuckolls, III wrote:
>
> At 11:44 PM 10/25/2013, you wrote:
>
> I am still stumped as to why you would recommend one battery. I could
> agree if the one alternator is guaranteed to work without the battery in
> the circuit, but not without that backup. You must think batteries are much
> more reliable than I do.
>
>
> Oky, let's ex[;pre that premise. What in your
> studies and/or experience with batteries leads
> you to believe that they demonstrate a risky,
> in-service failure rate?
>
>
> Before you add a second battery, are there things
> that can be done to mitigate your concerns and
> reduce in-service failures to acceptable risk
> levels?
>
> Recall that the original premise for dual batteries
> had nothing to do with worries for battery failure
> and everything to do with walling off known quantities
> of energy off to do separate tasks . . . where one
> of those tasks was critical to continued flight:
> keep the engine running. The two battery concept was
> never intended to be a hedge against the failure
> of one battery.
>
> **
>
> Bob . . .
>
> *
>
> *
>
> **
>
>
> *
>
> *
>
>
--
Zulu Delta
Mk IIIC
Thanks, Homer GBYM
It isn't necessary to have relatives in Kansas City in order to be unhappy.
- Groucho Marx
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 09:57 AM 10/26/2013, you wrote:
>Fred, Bob, et al, I have no dog in this fight, I've just been
>following the discussion but I've got to ask; with all these
>workarounds you're doing to make the EXPBus work with your
>airplane's systems, what is it buying you? The Spruce description of
>the EXPBus is all about easy squeazy installation and time savings,
>yet you're being forced into more and more redesign and adaptation
>in order to make it work for you. I realize that you're a long way
>down the road with this thing but have you thought about just
>grabbing a clean sheet of paper and sending the EXPBus to eBay?
For me, this discussion is NOT an attempt to
craft a Z-Figures for EXP-Bus. It's a new look
at Z-19 and other manifestations of two-battery
installations to explore well reasoned alternatives.
When and if the new Z-figure makes it to the back
of the book, then well see if we can fiddle with
an EXP-Bus to achieve the same architecture crafted
to design goals.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 09:44 AM 10/26/2013, you wrote:
>On Oct 26, 2013, at 3:51 AM, Ken wrote:
>
>>FWIW two parallel subaru oem EFI pumps from a 4 cylinder legacy
>>work fine with a oem regulator all of 1990 to 1994 vintage.
>>Pressure goes up no more than 2 psi. even with my somewhat
>>restrictive 5/16" return plumbing. Some fellows run both pumps for
>>landing and takeoff. Selecting both on is the first thing we do if
>>the engine is not running properly. Injector flow increases with
>>the square root of pressure so that is not an issue since normal
>>EFI pressures run around 38 psi above manifold pressure.
>
>Thanks Ken...I stand corrected...my engine at 1.8 L is a tad smaller
>than your Legacy...it's set up w/ 3/8" fuel supply line and a 1/4"
>return line using R9 injector hose aft of my firewall. I believe the
>fuel pressure regulator has been set to factor in whatever
>restrictive backpressure the 1/4" return line contributes.
>
>Ron Carr at RAM Performance sez my engine's fuel pressure will be 38
>psi at idle and rise to 43 psi at WOT.
The question to be answered for evolving this
new architecture is whether or not having two
pumps on at the same time represents any kind
of hazard.
The second pump is included to mitigate the
failure of the first pump. The first pump is
presently powered any time the MP-Bus is hot.
If the pump works, then the second pump is
not needed. If the first pump fails, the second
pump is available. At no time has anyone
suggested that the pumps should be operated
simultaneously on purpose.
Bob . . .
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: EXP 2 Bus workaround |
> Is anyone flying this combination of hardware? How much does
> IAS need to be reduced to stop a windmilling prop? The few
> times I stopped the prop on a TC airplane I had to really
> work at it. The idea that one needs access to a starter
> motor in flight is mostly without foundation. This is a
> fact you need to resolve for your harware combination.
Somewhat different hardware but indicative. With a 1.92 gear ratio and
a 3 bladed 72" non-tapered warp prop my ej22 windmills down to below 40
knots. However if I do intentionally stop it (difficult to do with a
best glide speed of about 65 knots), a 120 knot dive is insufficient to
get a restart. More interesting was that unlike many airplanes, my Rebel
has about the same glide ratio whether windmilling or stopped which
surprised me. Obviously I do not have one of the sprag clutch type
arrangements that have been so troublesome...
Ken
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 26, 2013, at 7:57 AM, Richard Girard wrote:
> Fred, Bob, et al, I have no dog in this fight, I've just been
following the discussion but I've got to ask; with all these workarounds
you're doing to make the EXPBus work with your airplane's systems, what
is it buying you? The Spruce description of the EXPBus is all about easy
squeazy installation and time savings, yet you're being forced into more
and more redesign and adaptation in order to make it work for you. I
realize that you're a long way down the road with this thing but have
you thought about just grabbing a clean sheet of paper and sending the
EXPBus to eBay?
Good question Rick...and one I've asked myself many times. My answer has
been that I'll chuck the EXP Bus when I reach the conclusion that doing
so will solve more problems than it creates. I'm still a long way from
that.
Your first question..."what is it buying you?"...is an even better
question, and I regret that I was simply too ignorant to read between
the lines of the marketing hype...I confess to have been dazzled by the
EXP's obvious complexity (to what end?) and my belief that "I guess I
need to buy one of these, cause I sure wouldn't want to trust myself to
build one".
As I presently understand things, the EXP can serve as my main power
distribution bus and provides circuits which can be used to power an
engine bus (or Motive Power Bus, to use Bob's new term) and an endurance
bus, both of which want to have alternate power feeds direct from the
battery.
All this seems fine and doable without making circuitry changes within
the EXP, something I'm loath to do, primarily because of my inexperience
and unfamiliarity w/ things electronic.
I can only commend Bob for his patience with me,
Fred
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
At 08:58 AM 10/26/2013, you wrote:
>On this list we have seen examples of internal battery failures and
>wire connector failures and switch failures. Granted that these
>things typically have low failure rates, but if they happen, you
>have no backup. By going with one battery and not knowing if the
>alternator will back you up you have elevated these failures to the
>status of a prop, engine, wing or control surface failure.
Let's concentrate on battery failures . . . and
the failure of components that hook that battery
to ground and the contactor stud.
What was the nature of failures internal to the
battery? What was the nature of failure for
any wires/connectors for which you have data?
Yes. Propellers have flown off the end of crankshafts,
wheels have departed their axles, elevator push-rods
have become disconnected. We read about and ponder these
events . . . did any one of these FEMA prompt recommendations
for dual engines, an extra landing gear strut and wheel
or perhaps splitting the elevator into two halves with
independent pushrods?
The rational response to such stories is to move
avoidance for root cause into prominent positions
for attention to detail. I've observed many
times in these writings that the greatest risk
to the airborne mission is the human element; a
risk for missing/ignoring critical fundamentals.
Can we deduce what attention to detail is needed
to make a battery as reliable as your prop bolts?
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
Bob...you asked:
> Is anyone flying this combination of hardware?
I asked a pal flying a RAM Sube powered Europa the following
questions:
>> In your bird, have you ever stopped your engine in flight?
>>
>> .If so, did the prop stop or windmill?
>>
>> If the prop stopped, how did you get it spinning again?
>>
>> Can you spin your starter w/ the Master Switch off?
>>
>> If not, would you like to be able to?
...and got this reply...not much help unfortunately.
Fred
> Hi Fred - no I've never stopped it. I thought about flying to an
aiport 40 miles north that has an 12000 ft runway and climb to 10000 ft
at 6 AM when no traffic was around and turn it off but haven't done it
yet.
>
> I can turn everything off but the fuel pumps and ignition and the
engine will run but I never thought of whether the starter
> would work - duh!!
>
> I'll have to check that and get back to you. I need to see if the
trim works with everything turned off as well. I'm wondering if with
the ac trimmed for cruise whether I would still have enough elevator for
the landing flare.
>
>
> XXXX
>
> From: fklein(at)orcasonline.com
> Subject: a Europa query
> Date: Fri, 25 Oct 2013 22:04:53 -0700
> To: XXXX(at)hotmail.com
>
> XXXX
>
> In your bird, have you ever stopped your engine in flight?
>
> .If so, did the prop stop or windmill?
>
> If the prop stopped, how did you get it spinning again?
>
> Can you spin your starter w/ the Master Switch off?
>
> If not, would you like to be able to?
>
>
> Sorry for all the questions...they are a consequence of an online
conversation I'm having with Bob Nuckolls at AeroElectric-list...excerpt
below:
>
>
> > (8) Starter can control from main bus.
>
> True...and...w/ my particular combination of engine,
reduction ratio, propeller, and aircraft performance envelope, although
I THINK that with engine out, prop would windmill sufficient to restart
engine, if Master switch was OFF, I'd like to be able to spin the
starter...that was the INTENT of what the diagram shows...What do you
think?...I'm unsure as to whether or not the wiring diagram allows for
that to happen.
>
> Is anyone flying this combination of hardware? How much does
> IAS need to be reduced to stop a windmilling prop? The few
> times I stopped the prop on a TC airplane I had to really
> work at it. The idea that one needs access to a starter
> motor in flight is mostly without foundation. This is a
> fact you need to resolve for your harware combination.
>
> Thanks once again for your help,
>
> Fred
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 26, 2013, at 8:49 AM, Ken wrote:
>
> > Is anyone flying this combination of hardware? How much does
> > IAS need to be reduced to stop a windmilling prop? The few
> > times I stopped the prop on a TC airplane I had to really
> > work at it. The idea that one needs access to a starter
> > motor in flight is mostly without foundation. This is a
> > fact you need to resolve for your harware combination.
>
> Somewhat different hardware but indicative. With a 1.92 gear ratio
and a 3 bladed 72" non-tapered warp prop my ej22 windmills down to below
40 knots. However if I do intentionally stop it (difficult to do with a
best glide speed of about 65 knots), a 120 knot dive is insufficient to
get a restart. More interesting was that unlike many airplanes, my Rebel
has about the same glide ratio whether windmilling or stopped which
surprised me. Obviously I do not have one of the sprag clutch type
arrangements that have been so troublesome...
Ken...interesting...my PSRU ratio is 1.9 to 1.0 and I too do not have a
sprag clutch...Fred
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
>>>Can you spin your starter w/ the Master Switch off?
Why would you want access to the
starter with the master switch off?
Under what conditions would you first
have the switch off and then find that
the engine has assumed a condition that
needs encouragement to get running again?
Assuming that the engine is at risk for
doing such a thing, what prevents you
from turning the master switch back on?
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 26, 2013, at 10:09 AM, Robert L. Nuckolls, III wrote:
>>>> Can you spin your starter w/ the Master Switch off?
>
> Why would you want access to the
> starter with the master switch off?
> Under what conditions would you first
> have the switch off and then find that
> the engine has assumed a condition that
> needs encouragement to get running again?
> Assuming that the engine is at risk for
> doing such a thing, what prevents you
> from turning the master switch back on?
Bob...my imagination knows no limits...I'm thinkin the Master's off
after detecting smoke and acrid smells coming from the panel...I'm
wanting to avoid the risk of flippin the Master back on and exacerbating
the situation which caused me to flip it off in the first place.
Fred
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
| Subject: | Re: EXP 2 Bus workaround |
>Bob...my imagination knows no limits...I'm thinkin the Master's off
>after detecting smoke and acrid smells coming from the panel...I'm
>wanting to avoid the risk of flippin the Master back on and
>exacerbating the situation which caused me to flip it off in the first place.
Okay, so that's a really big failure or a combination of
more than one failure giving you both Smoke + engine quits.
If you've suffered an event that stops the engine AND
smells bad . . . well . . .
The configuration on which we're sifting the sands
will allow you to turn off every switch except Engine A
without killing the engine electrically. Hmmm . . . perhaps
Engine A needs to run from the battery, Engine B from the
main bus. Now, the statement I made above is true.
Even so, unless you've got a clutched PRSU then you're
not going to need the starter anyhow. If the engine
has lost power due to same event that's causing smoke
. . . it's likely that mitigation of risk for
that cause is far outside the manipulation of any switches.
Bob . . .
________________________________________________________________________________
| From: | Fred Klein <fklein(at)orcasonline.com> |
| Subject: | Re: EXP 2 Bus workaround |
On Oct 26, 2013, at 10:56 AM, Robert L. Nuckolls, III wrote:
> Even so, unless you've got a clutched PRSU then you're
> not going to need the starter anyhow. If the engine
> has lost power due to same event that's causing smoke
> . . . it's likely that mitigation of risk for
> that cause is far outside the manipulation of any switches.
Bob...I wouldn't disagree with you.
The origin of this question arose when you noted that my Revision XX
diagram showed the starter switch fed from the engine (sorry, MP) bus
rather than the main bus...I still don't see the down side if I were to
do this.
Fred
________________________________________________________________________________
| From: | Bob McCallum <robert.mccallum2(at)sympatico.ca> |
| Subject: | EXP 2 Bus workaround |
Fred;
Not meaning to be critical or judgmental, but your "properly designed" and
maintained electrical system has somehow found a way to generate "smoke in
the cockpit" and you've turned off the master switch. So far so good.
The electrical problem (or fire) has progressed to the point of stopping the
engine and now you want to be further distracted by operating the starter to
turn over the failed engine rather than to "FLY THE AIRCRAFT" to a
October 15, 2013 - October 26, 2013
AeroElectric-Archive.digest.vol-lz