AeroElectric-Archive.digest.vol-cw
January 28, 2004 - February 10, 2004
From: | "Dan Checkoway" <dan(at)rvproject.com> |
Subject: | Fw: RV-7 wing tip COM antenna installation |
FYI, here's Bob's response.
)_( Dan
----- Original Message -----
From: "Bob Archer" <bobsantennas(at)earthlink.net>
Subject: Re: RV-7 wing tip COM antenna installation
>
> ----- Original Message -----
> From: "Dan Checkoway" <dan(at)rvproject.com>
> To: "Bob Archer"
> Cc:
> Sent: Tuesday, January 27, 2004 11:53 PM
> Subject: RV-7 wing tip COM antenna installation
>
> Hi Dan;
>
> The Com antenna was developed when the Horner type tips were in vogue,
where
> the bottom surface sweeps up to the upper surface. I still like them
better
> from my point of view. But we now have to contend with the so called
sheared
> tips.
>
> The picture you showed with the antenna sweeping up to the upper surface
is
> fine. A local fellow put in a sheet of fiber glass angled from the bottom
to
> the top with the antenna installed on it. He bent the antenna up just next
> to the grounding strip.
>
> The antenna needs to be grounded along the grounding strip, wires are not
> good. If you installed a sheet of aluminum between the grounding strip and
> the end of the wing for grounding that would suffice. Sandwiching the
> antenna between the tip and the glass is the normal way to do it.
>
> About routing the wires to the lights, I don't know. I know it works well
> the way it is shown on the drawing but other than that? I would guess that
> it would be ok but I have been fooled before. There are so many different
> ways things could be done I haven't been able to test for every
possibility.
>
> Just let me know if you have any further questions.
>
> Regards
>
> Bob
>
>
> > Bob,
> >
> > I purchased wing tip VOR & COM antennas from you last year, and I'm
> finally
> > getting around to installing them. The VOR antenna installation is a
> > no-brainer thanks to your instructions. The COM antenna, however, is a
> > little trickier due to the shape of the RV-7 wing tips (sheared, with
> > built-in lighting provision).
> >
> > Here is a web page with photos to illustrate my issues:
> >
> > http://www.rvproject.com/archer.html
> >
> > 1) Can the antenna be somewhat tightly arched and still perform well?
> > Bending it in an arch would improve its vertical profile, if that's
> > acceptable.
> >
> > 2) Can the antenna be grounded with a wire instead of directly
contacting
> > the airframe? I'd like to mount it a few inches outboard from the wing
> tip
> > opening, and I assume I would need to use a ground jumper wire?
> >
> > 3) Do the strobe/position wires absolutely need to route along the
> antenna's
> > leading edge even if they otherwise would not CROSS the antenna? Mine
can
> > run several inches ahead of the antenna, not crossing it.
> >
> > Please let me know if you need more photos or explanation of my issues.
> > Thanks very much!
> >
> > )_( Dan
> > RV-7 N714D
> > http://www.rvproject.com
> >
>
________________________________________________________________________________
From: | "'Scott Richardson'" <scott_m_richardson(at)sbcglobal.net> |
Vince, I'll send you a copy.
I just emailed Garmin Tech Support and asked them for it and they
emailed
it to me within the hour. Same for the GTX-327 inst manuals.
Scott
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Vincent Welch
Subject: AeroElectric-List: GNC-300XL
-->
Does anyone know where I can get an installation manual for a GNC-300XL?
I
have checked Garmin's web site but they only list a user's manual for
the
300XL. The web site has an installation manual for the 250XL. I need
to
make up a harness and I don't know if the pin outs are the same. The
user's
manual does not list pin outs.
Vince Welch
==
direct advertising on the Matronics Forums.
==
==
==
________________________________________________________________________________
Subject: | Re: Lighted Toggle Switches |
From: | John Schroeder <jschroeder(at)perigee.net> |
Hi Dave -
Very nice looking panels. Some questions:
What do they charge for a panel like one of yours?
What do you use for backlighting?
If individual lights, what is the spacing and position behind the panels?
What kind of sockets for the lights?
Many thanks for the information.
John Schroeder
________________________________________________________________________________
From: | kempthornes <kempthornes(at)earthlink.net> |
Subject: | Co ax antenna snap rings |
Hi,
Where can I get one of these?
(The about 0.040 inch snap ring that holds antenna cable plug to the rack
for radio, txp etc)
K. H. (Hal) Kempthorne
RV6-a N7HK - Three trips to OSH now.
PRB (El Paso de Robles, CA)
________________________________________________________________________________
From: | "David Schaefer" <dschaefer1(at)kc.rr.com> |
Subject: | Guarded Switches |
What's a good source for 'guarded switches' of the kind you pull out to be
able to turn on (or off)? B&C doesn't carry them. The only ones I can find
are Honeywell and they're $40-70 per switch!
Regards,
David Schaefer
RV6-A FADEC Finishing Kit
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: NKK LED toggle switches |
>
>Lyle,
> I believe that Kevin was referring to a double throw switch.
>Charlie Kuss
>
>
> >
> >Kevin,
> >
> >I am puzzled. What kind of switch are you referring to as 'progressive
> >on toggle'? I have never heard that used with regard to switches.
> >
Study the schematic symbols used for the -10 on-on-on
and -50 on-on-(on) switches in drawings at:
http://www.aeroelectric.com/temp/ProgressiveSW.pdf
Also see:
http://catalog.sensing.honeywell.com/printfriendly.asp?FAM=tr&PN=2NT1-10
and study the circuitry/operating action. When moving from one
extreme to the middle position, only one side of the switch transfers.
Continued motion in the opposite extreme transfers the second side,
hence the term "progressive" transfer.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Rochester cht sender. |
>
>
>Bob,
>
>I haven't posted anything here. Just been lurking and learning. I had
>to comment on the "carbine" lamp. I think those were "carbide" lamps.
>They generated acetylene to burn for light. Is my foggy recollection
>right?
yup, got my tongue tangled around my eyeteeth and
couldn't see what I was typing.
Bob . . .
________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
Subject: | Re: Lighted Toggle Switches now Panels |
About $75 to $100 per panel, and that's including all switches and
pots. Supply your own electrical components and it's considerably
cheaper. I'm planning to put some high intensity LEDs 4 or 5 inches behind
the panels facing forward. I have not yet decided on how to mount them, but
the panels are designed to be backlit, and they should look really sharp
with red LEDs illuminating them.
Dave
At 03:03 PM 1/28/2004, you wrote:
>
>
>Hi Dave -
>
>Very nice looking panels. Some questions:
>
>What do they charge for a panel like one of yours?
>
>What do you use for backlighting?
>
>If individual lights, what is the spacing and position behind the panels?
>
>What kind of sockets for the lights?
>
>Many thanks for the information.
>
>John Schroeder
>
>
________________________________________________________________________________
From: | Charlie Kuss <chaskuss(at)bellsouth.net> LED toggle |
Subject: | Re: Re: Lighted Toggle Switches was NKK |
LED toggle
LED toggle
Mike,
I stopped by my local BOW (Boat Owners Warehouse) this afternoon. I found several
of the Carling Technologies LT (lighted toggle) series switches there (re
packaged under different brand names) I paid about $13.50 each for these (compared
to $9 at my local Carling Dist.)
The Bat handles are definitely sturdier. The bright chrome and brushed chrome
models have a metal sleeve on them. It is "just" a sleeve, as you said.
One thing I noticed was that these switches are Made in Mexico. I also noticed
another brand (Hubbell) which are made in the USA. I just did a quick search
of their marine catalog. It appears that the selection is rather limited. I'll
try to call both Carling and Hubbell tomorrow, if I have time. I'll try to speak
to someone in the tech department. I want to find out what switch styles (electrically)
are available. I also want to see if Carling has any LT series switches
that are USA made. Externally, the Carling LTs look good. No idea what
they are like inside. The ones I bought are rated for 15 amps DC. I'd like to
ask the tech folks how many cycles these switches are designed for. (MTBF)
Charlie
>
>The broken ones were paddle style, but I believe both
>styles are translucent plastic (light pipes). I think
>there is a metal sleeve option for the bat style, but
>it is just a sleeve (I think).
>
>Mike
>
>__________________________________
>
>
________________________________________________________________________________
Subject: | Fast on's to make Terminal Blocks |
From: | Don Boardman <dboardm3(at)twcny.rr.com> |
Hi All,
Thanks very much for the responses to my Fast-on request.
I guess I need to improve my searching skills in the big catalogs!
The strips of 5, 90 degree doubles, would be tempting if I was into making
larger grounding blocks. I already have a 24 from B&C and I will only need a
few grounds on the engine side of the firewall.
I am thinking that the single, double male 90's or 45's, would be fine to
make up say an 8-10 terminal ground block.
Anyone working with the 45's ?
I have also been debating how to make connections for situations that
typically use the screw type terminal blocks. (Float wiring, etc)
WHY NOT USE THE SEPARATE DOUBLE MALE FAST-ON'S RIVETED/FASTENED TO A
NONCONDUCTIVE SURFACE TO FABRICATE FAST-ON TERMINAL BLOCKS?
This would seem to give the convenience of a terminal block with the
desirable connectivity of Fast-ons.
Comments ...
Don B.
________________________________________________________________________________
From: | "Terrence Gardner" <ttandt(at)mindspring.com> |
Subject: | Trailer Plugs For Wing Root Disconnect |
Weather Pack (Trailer Plugs) fabrication kits are available in various size
from longacreracing.com or IrvanSmith.com. You can make up a custom
disconnect as described in the AEC using Mil spec wire as opposed to the 9
strand commonly found on these plugs at auto parts stores. These sites have
a number of other tools/goodies
Terry Gardner
RV9a
________________________________________________________________________________
From: | Fiveonepw(at)aol.com |
Subject: | Re: Fast on's to make Terminal Blocks |
In a message dated 1/28/04 10:35:59 PM Central Standard Time,
dboardm3(at)twcny.rr.com writes:
> I already have a 24 from B&C and I will only need a
> few grounds on the engine side of the firewall.
>
You may wish to consider just taking the grounds through the firewall along
with all the other stuff if there are only a few, as you say. I'd suggest this
would be a little cleaner with less connections in the engine environment.
>
> I have also been debating how to make connections for situations that
> typically use the screw type terminal blocks. (Float wiring, etc)
>
You'll need to use ring terminals (PIDG) for the floats and it would probably
be a good idea to add a separate ground wire to the sender mounting plate.
Another ring terminal with a star washer under one of the screw heads should
suffice. I ran the ground wire to a local ground on the fuselage inside the
wing root with another ring terminal, FWIW - and by the way, Vans floats & gauges
tested amazingly accurate in the 0-10 gal. range- very pleased with that!
> WHY NOT USE THE SEPARATE DOUBLE MALE FAST-ON'S RIVETED/FASTENED TO A
> NONCONDUCTIVE SURFACE TO FABRICATE FAST-ON TERMINAL BLOCKS?
>
> This would seem to give the convenience of a terminal block with the
> desirable connectivity of Fast-ons.
>
> Comments ...
As a general rule, make as few connections as possible of ANY KIND anywhere
in your system- ideally a wire should go directly from a device to a power
source or ground. Every joint adds a possible failure point. I'll take
reliability over convenience any day! There are plenty of sound ways to reconnect
a
wire if it needs to be cut...
From The PossumWorks in TN
Mark Phillips - all-electric RV-6A per Aeroelectric design & EVERYTHING
WORKS! 8-)
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Guarded Switches |
>
>
>What's a good source for 'guarded switches' of the kind you pull out to be
>able to turn on (or off)? B&C doesn't carry them. The only ones I can find
>are Honeywell and they're $40-70 per switch!
Yup, that's why B&C doesn't carry them. These are indeed a low
volume, specialty switch with prices to match.
I know of no inexpensive sources of new switches with
this feature.
Bob . . .
________________________________________________________________________________
From: | "Bruce Gray" <Bruce(at)glasair.org> |
Subject: | Guarded Switches |
Bob's right, my airplane has one, used for gear activation. Do a search
on MS24658-23D.
Bruce
www.glasair.org
-----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
Subject: Re: AeroElectric-List: Guarded Switches
>
>
>What's a good source for 'guarded switches' of the kind you pull out to
be
>able to turn on (or off)? B&C doesn't carry them. The only ones I can
find
>are Honeywell and they're $40-70 per switch!
Yup, that's why B&C doesn't carry them. These are indeed a low
volume, specialty switch with prices to match.
I know of no inexpensive sources of new switches with
this feature.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Starter Engaged Light |
>
>
>Bob Nuckolls -
>
>On Z-14, where is the best place to take power for a "Starter Engaged"
>annunciator light?
Any place downstream of the starter contactor . . . or from the
contactor's "I" terminal if it has one. Be sure to fuse or
fuselink this lead AT the POWERED end.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Alternator - Thermocouples |
>
> >
> >After talking to Vans, they said I probably blew the
> >voltage regulator by switching off the field that
> >disconnected the B-lead at the contactor. Switching
> >off field after it has started doesn't stop the
> >alternator because it gets field power from the
> >B-lead. They said they've been seeing this a lot
> >lately on alternators wired per z-24.
> >
> >Would it be an accurate statement to say that:
> >"Turning off the alt field after it has been turned on
> >for an internally regulated alternator wired as
> >depicted in Z-24 is a death sentence for the
> >alternator. An overvolt condition will also open the
> >contactor and finish off the alternator for good."
> >
> >If so, this might be a handy piece of information to
> >add to that diagram because it would have saved me
> >some trouble.
This is the first I've heard of it. Gee, if Van's
has seen a rash of these events, it would have been
really nice of them to let me know about it.
I'm looking into this. Watch this space.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Wiring PTT button |
>
>Bob, these are great explanations and very helpful. You should get some
>kind of special acknowledgement for your work supporting homebuilders.
>--Kent A.
But I DO get rewarded . . . OBAM aircraft are coming on line
in ever increasing numbers unencumbered by no-value-added
assistance by those-who-know-more-about-airplanes-than-we-do.
Better yet, OBAM aircraft performance and return on investment
stands head and shoulders above stuff pushed off the assembly lines.
For me, this is many times more satisfying than any placard
on the wall or trophy on the shelf . . . but thank you for
thinking of me!
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | Speedy11(at)aol.com |
Subject: | Re: AeroElectric-List Digest: 41 Msgs - 01/28/04 |
In a message dated 1/29/04 2:58:55 AM Eastern Standard Time,
aeroelectric-list-digest(at)matronics.com writes:
<< I am leaning more toward the bat (aka Snapkap in the Carling Catalog)
style handles
as I feel that they would be more durable. >>
Charlie,
The Carling web site, in regard to the SnapKap switches says, "The LT-Series
toggle switches are AC rated illuminated toggle switches featuring a
three-color lighting sequence from a single lamp." I understood that we shouldn't
use
AC switches because when used with DC power the contacts burn slightly each
time they are thrown thus building up over time and causing long term trouble.
Is it okay to use AC switches?
Stan Sutterfield
Tampa
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Shielded sensor wires |
>
>Terry,
>
>The thermocouple wire can be connected with crimped butt splices. However
>note that in my opinion, which should be taken with a grain of salt,
>soldering and heat shrink makes better connections.
>
>Regards,
>Trampas Stern
It's true, and contrary to what I wrote in the 'Connection
that thermocouple wire can be soft-soldered with readily
available tin-lead solder with the right kind of flux. I'm
considered doing a comic-book on this technique. Given
my earlier (20+ years ago) disappointing experiences with
soft solder, it's important that whatever we recommend has
a high-order probability of success for the neophyte builder.
In the mean time, techniques that get gas-tight grips
on thermocouple wires like silver solder, PIDG crimps,
4-quad d-sub crimps, etc. are attractive for their
lack of process sensitivity.
Bob . . .
________________________________________________________________________________
From: | Paul <pwilson(at)climber.org> |
Subject: | Re: Guarded Switches |
Bought a simple on-off from John Deere for my tractor. It is a pull to move type.
Dont have the tractor so I cannot look up the brand. It was used to control
the PTO.
BTW, Auto Zone has flip covers in various colors to protect toggles. They have
a simple attachment that is held by the switch.
Paul
>
>
>>
>>
>>What's a good source for 'guarded switches' of the kind you pull out to be
>>able to turn on (or off)? B&C doesn't carry them. The only ones I can find
>>are Honeywell and they're $40-70 per switch!
>
> Yup, that's why B&C doesn't carry them. These are indeed a low
> volume, specialty switch with prices to match.
>
> I know of no inexpensive sources of new switches with
> this feature.
>
> Bob . . .
--
________________________________________________________________________________
From: | "Neville Kilford" <nkilford(at)etravel.org> |
Subject: | Re: Starter Engaged Light |
Bob,
Why is it necessary to fuse the warning light (not an accusation, by the
way)? I'm thinking that the light would only be powered when the contactor
is engaged -- the same as the starter motor, which isn't protected.
TIA.
Nev
--
Jodel D150 in progress
UK
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: Starter Engaged Light
>
> >
> >
> >Bob Nuckolls -
> >
> >On Z-14, where is the best place to take power for a "Starter Engaged"
> >annunciator light?
>
> Any place downstream of the starter contactor . . . or from the
> contactor's "I" terminal if it has one. Be sure to fuse or
> fuselink this lead AT the POWERED end.
>
> Bob . . .
>
________________________________________________________________________________
From: | F1Rocket(at)comcast.net |
Subject: | Re: Starter Engaged Light |
What's the risk if power for the light is taken from the fat terminal on the contactor
that goes to the starter, as long as it is fuselinked?
Randy
http://f1rocket.home.comcast.net/
> >Bob Nuckolls -
> >
> >On Z-14, where is the best place to take power for a "Starter Engaged"
> >annunciator light?
>
> Any place downstream of the starter contactor . . . or from the
> contactor's "I" terminal if it has one. Be sure to fuse or
> fuselink this lead AT the POWERED end.
>
> Bob . . .
>
________________________________________________________________________________
Subject: | Re: Lighted Toggle Switches now Panels |
From: | John Schroeder <jschroeder(at)perigee.net> |
Dave -
Thanks for the info. I'm planning on using LED's. The engraved panels will
be over an aluminum panel of the same size. Looks like we'll have to
experiment on the size and placement of the LED's. Drill holes in the
aluminum plate and pot the LED's into the holes? Do you know of any good
mounting hardware for LED's? Might be able to adapt Bob's roll-your-own
kind that he has posted on his site.
John
________________________________________________________________________________
Subject: | Ground Power Plug |
From: | John Schroeder <jschroeder(at)perigee.net> |
Hi Bob -
We're using Z-14 on a Lancair ES (batteries in the rear). We made and
installed your "Piper Style" external power receptacle. You show a diode
installed on the sensing pin in your diagrams that use the "Cessna Style"
receptacle.
It does not appear that one needs or can use a diode in a polarity sensing
circuit for the Piper receptacle. Correct?
If you need one, where would it go?
Thanks,
John Schroeder
--
________________________________________________________________________________
From: | "Paul Messinger" <paulm(at)olypen.com> |
Subject: | Re: Guarded Switches // D-sub dust covers |
Prics and availability depends on needing a large body switch with 10-20amp
rating. Lots of small body switches with 5-6 amp contacts (and the bat
handle is full size so looks are close to the same) are available at a
reasonable cost. I have used them for many, many years with no problems on
DC applications. Available in SPDT, DPDT, 3PDT, 4PDT with pricing from $6
to $15 depending on supplier, # poles, and MFGR.
Mine have available screw on caps in RED or Aluminum color.
Use the following link with the mfgrs part # to find stock.
www.findchips.com
C&K try "7103k" for the part search without the ""
ITT try "7203K
NKK try "M2012LL1W01",find the catalog page for different poles etc Mouser
page 831 for example
Alco try "MTL106"
NOT seen by me but Alco lists a DP3T (ON-ON-ON) switch. MTL 406PA (Mouser
has stock)
I have not tried all of the above (using find chips but did try many) and
obtained the MFGR's part # from the following catalogs:
Digi-Key, Mouser, Newark, Allied, all list this type of switch and use of
find chips link provides a near instant stock and price comparison.
DUST CAPS FOR D-SUB CONNECTORS
Some time back there was a request for dust caps for the D-Sub connectors.
All of the above distributors list them in low quanity and price in various
sizes.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: Guarded Switches
>
>
> >
> >
> >What's a good source for 'guarded switches' of the kind you pull out to
be
> >able to turn on (or off)? B&C doesn't carry them. The only ones I can
find
> >are Honeywell and they're $40-70 per switch!
>
> Yup, that's why B&C doesn't carry them. These are indeed a low
> volume, specialty switch with prices to match.
>
> I know of no inexpensive sources of new switches with
> this feature.
>
> Bob . . .
>
>
________________________________________________________________________________
Subject: | Re: Starter Engaged Light |
From: | John Schroeder <jschroeder(at)perigee.net> |
Randy -
What is fuselinked? The fat starter wire? The wire going back to the light?
I read Bob's response as fuzing or fuzelinking the wire back to the light.
I do not believe that the starter has any fuzing in the fatwire from the
contactor to the starter motor.
Cheers,
John
>
> What's the risk if power for the light is taken from the fat terminal on
> the contactor that goes to the starter, as long as it is fuselinked?
>
> Randy
> http://f1rocket.home.comcast.net/
>
>> >Bob Nuckolls -
>> >
>> >On Z-14, where is the best place to take power for a "Starter Engaged"
>> >annunciator light?
>>
>> Any place downstream of the starter contactor . . . or from the
>> contactor's "I" terminal if it has one. Be sure to fuse or
>> fuselink this lead AT the POWERED end.
>>
>> Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Starter Engaged Light |
>
>What's the risk if power for the light is taken from the fat terminal on
>the contactor that goes to the starter, as long as it is fuselinked?
none at all.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
There's more to switch behavior than pricing, mil-spec,
UL approved, etc., etc.
While working a task for RAC, I've been discovering the
effects of contact bounce on relays and switches. Just
took these traces on the bench comparing transition and
bounce characteristics of two products with big differences
in perceived "quality".
It's bounce characteristics of Microswitch products
that that uncovered a design deficiency in the ov protection
system of LR series regulators at RAC a few years ago.
When it gets down to the simple-ideas, one can encounter
some pretty profound differences that may or may not show
up in the advertising hype or published specifications.
See:
http://www.aeroelectric.com/articles/bounce.pdf
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> 01/28/04 |
Subject: | Re: AeroElectric-List Digest: 41 Msgs - |
01/28/04
01/28/04
>
>In a message dated 1/29/04 2:58:55 AM Eastern Standard Time,
>aeroelectric-list-digest(at)matronics.com writes:
>
><< I am leaning more toward the bat (aka Snapkap in the Carling Catalog)
>style handles
> as I feel that they would be more durable. >>
>
>Charlie,
>The Carling web site, in regard to the SnapKap switches says, "The LT-Series
>toggle switches are AC rated illuminated toggle switches featuring a
>three-color lighting sequence from a single lamp." I understood that we
>shouldn't use
>AC switches because when used with DC power the contacts burn slightly each
>time they are thrown thus building up over time and causing long term
>trouble.
>Is it okay to use AC switches?
See http://www.aeroelectric.com/articles/swtchrat.pdf
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Starter Engaged Light |
>
>
>Bob,
>
>Why is it necessary to fuse the warning light (not an accusation, by the
>way)? I'm thinking that the light would only be powered when the contactor
>is engaged -- the same as the starter motor, which isn't protected.
you aren't going to burn a 2 or 4AWG wire . . . you'll burn a
22AWG lamp wire in seconds. When we owned the airport at Benton,
had a mechanic attempt to crank an engine without attaching
the crankcase to firewall jumper . . . did it twice on different
airplanes. Made for lots of smoke in a couple of seconds and
lots of work to replace wires. I didn't give him a third crack
at it. General rule of thumb is any wire NOT part of fat feeders
for alternator, battery or cranking motors that is 6" or longer
get protected. That's why you see fusible links in fuesblock-to-regulator
feedwire our z-figures.
Bob . . .
________________________________________________________________________________
Subject: | Re: Guarded Switches // D-sub dust covers |
From: | John Schroeder <jschroeder(at)perigee.net> |
Paul -
That website is fabulous. Thanks for sharing it with us.
John
> Use the following link with the mfgrs part # to find stock.
>
> www.findchips.com
________________________________________________________________________________
Subject: | External Power Receptacle |
From: | John Schroeder <jschroeder(at)perigee.net> |
Bob Nuckolls -
Disregard my request about the diode in the Z-14/External Power diagram. I
found one of your AutoCAD drawings in your "Weekend Seminars" wirebook
that shows the wiring for the "Piper" receptacle. It does not show a diode
in the circuit.
I also saw the fuzing and takeoff point for the "Starter Engaged" light in
another drawing. It comes off the starter side of the starter solenoid.
Thanks,
John
--
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Fig Z-16 Rotax 912/914 System |
>
>
>Bob et.al.
>
>I feel deprived not being able to attend one of your seminars owing to
>where I live. I am therefore grateful for the opportunity to tap into
>the combined wisdom available on this list.
>
>In my endeavour to more fully understand the principles being applied
>and to try to gain more confidence in my ability to interpret the
>diagrams, I would be most obliged if you or others could help me with
>the following queries - ALL in respect of Fig Z-16 Rotax 912/914
>System. I have a plain vanilla Rotax 912 engine and a Europa aircraft
>(composite) with no bells or whistles and will be flying only day VFR.
>
>My queries
>
>1 Reason for the fusible link in series with the 5A CB in the line
>from the main bus to terminal 5 on S1, Master Switch?
The wire from bus to breaker is more than 6" long and has
smoke-risk due to it's length an small size. A fuse won't protect
it because we're trying to open a breaker downstream. Some 5A
breakers are so slow that they'll open a 30A fuse upstream. The
fusible link provides a robust (slow acting) protection of that
wire.
>2 Reason for the fusible link as opposed to an inline fuse in
>series with the Alternator Warn light?
See above.
>3 As I see the Alt Warn light in this circuit, the warning it
>provides is that the alternator is "off line" rather than that it is not
>charging.
Correct. Active notification of low voltage is the ulitmate
warning light.
> If I also connect another warning light between terminal 4 of
>the Master Switch and terminal "L" on the regulator (or "L" and "C" on
>the regulator), will this light illuminate when the engine is not
>running with the Master Sw turned fully on and extinguish as the
>alternator voltage rises after start-up?
Low voltage warning would be better . . . it catches low alternator
output for ANY reason.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Ken Brooks" <kenbrooks(at)charter.net> |
Subject: | Another option for Van's ABS air vents |
While looking at the Aircraft Simulators site for backlit panel switches,
etc., I noticed they also had some attractive eyeball vents (ABS plastic)
that are smaller than the large ones that Van's sells. Thought others might
be interested. Cost is $25 ea.
http://www.aircraftsimulators.com/litevent.html
Ken Brooks
Roscoe, IL
Mired down with the canopy
________________________________________________________________________________
From: | "Kenneth Gresham" <kgresham(at)mtco.com> |
Does anyone have a suggestion for a simple quick connection for five or more wires.
This is for an electric trim tab servo and I would like to easily remove
for repair.
________________________________________________________________________________
From: | "Alex Peterson" <alexpeterson(at)usjet.net> |
> Does anyone have a suggestion for a simple quick connection
> for five or more wires. This is for an electric trim tab
> servo and I would like to easily remove for repair.
Someone suggested a while back using high quality R/C aircraft
connectors. Sounds good to me.
Alex Peterson
Maple Grove, MN
RV6-A N66AP 434 hours
www.usfamily.net/web/alexpeterson
________________________________________________________________________________
From: | "Randy Pflanzer" <f1rocket(at)comcast.net> |
Subject: | Re: Starter Engaged Light |
That means to install a "fusible link" as a type of protection at the power
end of a circuit. It functions like a fuse or circuit breaker. You can buy
kits from B&C. Essentially, all it is ...is a smaller gauge wire than the
wire it is protecting, covered in a fireproof sheath. If the circuit gets
an overload, this short piece of wire will get red hot and break before the
wire in the circuit fries. The sheath keeps it from melting anything around
it. Sort of a "poor man's" fuse. Very ingenious, cheap, and simple to
install.
----- Original Message -----
From: "John Schroeder" <jschroeder(at)perigee.net>
Subject: Re: AeroElectric-List: Starter Engaged Light
>
> Randy -
>
> What is fuselinked? The fat starter wire? The wire going back to the
light?
>
> I read Bob's response as fuzing or fuzelinking the wire back to the light.
> I do not believe that the starter has any fuzing in the fatwire from the
> contactor to the starter motor.
>
> Cheers,
>
> John
>
>
> >
> > What's the risk if power for the light is taken from the fat terminal on
> > the contactor that goes to the starter, as long as it is fuselinked?
> >
> > Randy
> > http://f1rocket.home.comcast.net/
> >
> >> >Bob Nuckolls -
> >> >
> >> >On Z-14, where is the best place to take power for a "Starter Engaged"
> >> >annunciator light?
> >>
> >> Any place downstream of the starter contactor . . . or from the
> >> contactor's "I" terminal if it has one. Be sure to fuse or
> >> fuselink this lead AT the POWERED end.
> >>
> >> Bob . . .
>
>
________________________________________________________________________________
Subject: | RE: Quick connects |
From: | "Condrey, Bob (US SSA)" <bob.condrey(at)baesystems.com> |
Here's Bob's suggestion:
http://www.aeroelectric.com/articles/macservo/macservo.html
________________________________________________________________________________
From: | "Larry Bowen" <Larry(at)BowenAero.com> |
I did it like this:
http://bowenaero.com/copper/displayimage.php?album=search&cat=0&pos=0
-
Larry Bowen
Larry(at)BowenAero.com
http://BowenAero.com
> -----Original Message-----
> From: Kenneth Gresham [mailto:kgresham(at)mtco.com]
> Sent: Thursday, January 29, 2004 7:03 PM
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Quick connects
>
>
> -->
>
> Does anyone have a suggestion for a simple quick connection
> for five or more wires. This is for an electric trim tab
> servo and I would like to easily remove for repair.
________________________________________________________________________________
Subject: | Re: Quick connects |
From: | John Schroeder <jschroeder(at)perigee.net> |
See Bob Nuckolls How-to paper on his website. It adapts a DB9 connector
for trim tab servos. If you can't find it, let me know and I'll email you
a copy of it.
John
wrote:
>
>
> Does anyone have a suggestion for a simple quick connection for five or
> more wires. This is for an electric trim tab servo and I would like to
> easily remove for repair.
>
>
--
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Co ax antenna snap rings |
>
>
>Hi,
>
>Where can I get one of these?
>
>(The about 0.040 inch snap ring that holds antenna cable plug to the rack
>for radio, txp etc)
Check out the assortment of special hardware in any
REAL hardware store. ACE Hardware is one. They have
drawers with little bins containing assortments of
specialty hardware. Measure the o.d. of the groove
in the connector and see if the hardware store has
a snap ring very close to the size you need.
Bob . . .
________________________________________________________________________________
From: | "Darwin N. Barrie" <ktlkrn(at)cox.net> |
Subject: | Re: Quick connects |
Deans 5 pin gold connectors available from www.radicalrc.com. Small, light
and a very solid connect.
Darwin N. Barrie
Chandler AZ
----- Original Message -----
From: "Alex Peterson" <alexpeterson(at)usjet.net>
Subject: RE: AeroElectric-List: Quick connects
>
> > Does anyone have a suggestion for a simple quick connection
> > for five or more wires. This is for an electric trim tab
> > servo and I would like to easily remove for repair.
>
> Someone suggested a while back using high quality R/C aircraft
> connectors. Sounds good to me.
>
> Alex Peterson
> Maple Grove, MN
> RV6-A N66AP 434 hours
> www.usfamily.net/web/alexpeterson
>
>
________________________________________________________________________________
Subject: | Re: Quick connects |
I bought a the Hirose mini circular connector from Digikey. They are very
small, easy to attach, locking, not real expensive, and sealed. I haven't
installed it yet but it looks perfect for the elevator trim to 5 wire Ray Allen
cable.
There is a photo at the following site.
http://www.hirose.com/
________________________________________________________________________________
From: | richard(at)riley.net |
I have one last CNX-80 for sale, new with full warrantee, $8750, doesn't
have to be installed by a dealer.
________________________________________________________________________________
From: | "Kingsley Hurst" <khurst(at)taroom.qld.gov.au> |
Subject: | Fig Z-16 Rotax 912/914 System |
>1 Reason for the fusible link in series with the 5A CB in the
line
>from the main bus to terminal 5 on S1, Master Switch?
The wire from bus to breaker is more than 6" long and has
smoke-risk due to it's length an small size. A fuse won't protect
it because we're trying to open a breaker downstream. Some 5A
breakers are so slow that they'll open a 30A fuse upstream. The
fusible link provides a robust (slow acting) protection of that
wire.
Thank you for the clarification Bob, much appreciated.
Kingsley Hurst
________________________________________________________________________________
From: | "Troy Scott" <tscott1217(at)bellsouth.net> |
Subject: | several questions |
Bob Nuckolls et al,
Today I was at Home Depot "Electrical Solder" described as "lead free", 95%
tin/5% antimony. After looking at several brands, I realized that ALL the
"electronics grade" solder there was "lead free". Is this because of new
government guidelines or some lawsuit problem? Is this solder good for our
purposes?
Bob, I've ordered the circuit board for your Audio Isolation Amplifier. I'd
like to use it to eliminate the need for an audio panel. I'll have an SL30
Nav-Com, another Com- only radio and an RST Marker Beacon Receiver. I plan
to just use the volume controls to select what I want to hear. I want to
utilize the internal intercom in the SL30. Do you foresee any problems with
this audio setup? Have you considered a way to make the stereo input "auto
mute" in favor of communications from ATC?
In your book I read about the method for trimming the quarter-wave dipole
antennas like I have installed in my Glasair. You mention a "through-line
wattmeter". I haven't been able to find out anything about this device.
Can you elaborate?
I've been planning to mount my transponder antenna on an aluminum inspection
cover. I read in your book that the ground plane diameter should be twice
the element length. Does this mean EXACTLY twice the length of the element?
Of is a little bigger OK? I see this style antenna mounted on the bottom of
aluminum airplanes where the whole airplane, or at least the whole panel is
the ground plane.... Anyway, the round aluminum inspection panel where I'd
planned to mount it is 6 5/8" in diameter. I also have another inspection
panel available that is 5 5/8".
Regards,
Troy Scott
tscott1217(at)bellsouth.net
________________________________________________________________________________
From: | "Dan Checkoway" <dan(at)rvproject.com> |
Subject: | Re: Quick connects |
All of the suggestions given are good ones. The problem with using a
connector, though, is that if you need to remove the elevator, you'll have
to remove the connector...not convenient. (at least that's the way it is on
an RV...just a small round hole for the wire to pass through the elevator
spar)
Here's what I did instead:
http://www.rvproject.com/20040124.html
I used D-sub pins and sockets, and that's it. No connector body to worry
about. Heat shrink over each pin/socket pair, and then heat shrink over the
bundle. Need to remove the servo, cut the heat shrink, pull the
pins/sockets apart. Need to remove the elevator? Same deal, and there's no
fat connector to worry about.
Best of luck,
)_( Dan
RV-7 N714D
http://www.rvproject.com
----- Original Message -----
From: "Kenneth Gresham" <kgresham(at)mtco.com>
Subject: AeroElectric-List: Quick connects
>
> Does anyone have a suggestion for a simple quick connection for five or
more wires. This is for an electric trim tab servo and I would like to
easily remove for repair.
>
>
________________________________________________________________________________
From: | "Michel RIAZUELO" <mt.riazuelo(at)wanadoo.fr> |
Subject: | Re: Fig Z-16 Rotax 912/914 System |
Bob,
You answered to Kinsley :
> The wire from bus to breaker is more than 6" long and has
> smoke-risk due to it's length an small size.
On my MCR SPORTSTER (ROTAX 912 and Z-16), the line from terminal 5 on S1, Master
Switch and the 5A CB is 2" long. The line from the 5A CB and the MAIN BUS
is 4" long.
Can I use 22AWG for the two line, without FuseLink ?
I have sawn on some aircraft silicone sleeves to "protect" FastOn terminals. I
use B&C ones. I never read anything about that on the Aeroelectric list. Usefull
or useless ?
Thanks again for the job you do for us.
Michel RIAZUELO
MCR SPORTSTER
________________________________________________________________________________
Subject: | Re: Fig Z-16 Rotax 912/914 System |
> I have sawn on some aircraft silicone sleeves to "protect" FastOn
terminals. I use B&C ones. I never read anything about that on the
Aeroelectric list. Usefull or useless ?
>
Hi Michel and all,
In my opinion, "Faston protection" is not a big issue. We didn't bother with
it.
Regards,
Gilles
MCR 4S & Rotax 914
Cooling ducts definition in progress
________________________________________________________________________________
From: | Charlie Kuss <chaskuss(at)bellsouth.net> 01/28/04 |
Subject: | Re: AeroElectric-List Digest: 41 Msgs - |
01/28/04
01/28/04
Bob states in the AeroElectric book that the 120 AC volt rating (for amps) is equivalent
for 12 volts DC.
Charlie
>
>In a message dated 1/29/04 2:58:55 AM Eastern Standard Time,
>aeroelectric-list-digest(at)matronics.com writes:
>
><< I am leaning more toward the bat (aka Snapkap in the Carling Catalog)
>style handles
> as I feel that they would be more durable. >>
>
>Charlie,
>The Carling web site, in regard to the SnapKap switches says, "The LT-Series
>toggle switches are AC rated illuminated toggle switches featuring a
>three-color lighting sequence from a single lamp." I understood that we shouldn't
use
>AC switches because when used with DC power the contacts burn slightly each
>time they are thrown thus building up over time and causing long term trouble.
>Is it okay to use AC switches?
>Stan Sutterfield
>Tampa
>
>
________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
Subject: | Re: Lighted Toggle Switches now Panels |
I haven't planned anything fancy, since they will be hidden behind the
panel and hopefully have a very long lifetime. My whole airplane is made
of epoxy, maybe I'll just drill a little hole in the fiberglass panel,
stick the LED into the hole and glue it in place with 2 minute stuff. I'm
thinking one LED aimed at the top back side and one at the bottom should
give plenty of illumination.
Dave
>
>
>Dave -
>
>Thanks for the info. I'm planning on using LED's. The engraved panels will
>be over an aluminum panel of the same size. Looks like we'll have to
>experiment on the size and placement of the LED's. Drill holes in the
>aluminum plate and pot the LED's into the holes? Do you know of any good
>mounting hardware for LED's? Might be able to adapt Bob's roll-your-own
>kind that he has posted on his site.
>
>John
>
>
Dave Morris
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: several questions |
>
>
>Bob Nuckolls et al,
>
>Today I was at Home Depot "Electrical Solder" described as "lead free", 95%
>tin/5% antimony. After looking at several brands, I realized that ALL the
>"electronics grade" solder there was "lead free". Is this because of new
>government guidelines or some lawsuit problem? Is this solder good for our
>purposes?
I don't know. We're all aware of the ever increasing shrillness of
voices decrying this gawdawful pollutant and that stress on the
environment with all too many politicians ready to mount up with
their white hats on and come charging over the hill to our "rescue".
Problem is that there's so much BS stirred in with the real science
that it's difficult to sort out the pieces. Solders in hardware stores
for copper plumbing have been lead-free for a lot of years. Yeah,
I can see some basic logic in that . . . we DO drink water that flows
past the joints.
You might poke around on the 'net and see what the rumblings are
about non-lead solders for electronics. Not having any good
information one way or the other, I'd stick with what we know
works VERY well, good ol' 60/40 or 63/37 tin-lead with a good
flux. Get a name brand like Kester or Multicore.
>Bob, I've ordered the circuit board for your Audio Isolation Amplifier. I'd
>like to use it to eliminate the need for an audio panel. I'll have an SL30
>Nav-Com, another Com- only radio and an RST Marker Beacon Receiver. I plan
>to just use the volume controls to select what I want to hear. I want to
>utilize the internal intercom in the SL30. Do you foresee any problems with
>this audio setup?
Lots of folks have been doing this.
>Have you considered a way to make the stereo input "auto
>mute" in favor of communications from ATC?
There are a ton of features we could build into an audio
system . . . but that means going toe-to-toe with folks
who have been doing that for years and doing it rather
well. I prefer to offer goodies you can't get anywhere
else -OR- item that can blow away some piece of junk
already in the markeplace.
>In your book I read about the method for trimming the quarter-wave dipole
>antennas like I have installed in my Glasair. You mention a "through-line
>wattmeter". I haven't been able to find out anything about this device.
>Can you elaborate?
Here's the gold standard in thru-line wattmeters.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3074027135&category=48701
You also have to have a "slug" that covers the frequency
and power range of interest. They're kinda pricey for a
one time need. See if you can borrow/rent one from a local
two-way radio shop . . . or pay one of their techs to come
out and do a look-see on your antennas.
Here's my favorite antenna tool.
http://www.mfjenterprises.com/products.php?prodid=MFJ-259B
>I've been planning to mount my transponder antenna on an aluminum inspection
>cover. I read in your book that the ground plane diameter should be twice
>the element length. Does this mean EXACTLY twice the length of the element?
>Of is a little bigger OK? I see this style antenna mounted on the bottom of
>aluminum airplanes where the whole airplane, or at least the whole panel is
>the ground plane.... Anyway, the round aluminum inspection panel where I'd
>planned to mount it is 6 5/8" in diameter. I also have another inspection
>panel available that is 5 5/8".
The purists will debate at length and with enthusiasm
as to the effectiveness of finely tuned antennas. Fact
is that from an airplane, everything you talk/listen to
is line-of-sight . . . a wet string would get you 90%
coverage of your area of interest. When it's EASY to
be precise, why not? If convenience drives you to consider
the inspection plates, go ahead. Nobody will know the
difference but you . . and that only because you took
the time to worry about it a little.
Bob . . .
________________________________________________________________________________
Subject: | Alternator Field Wiring |
From: | John Schroeder <jschroeder(at)perigee.net> |
Bob -
Z-14. In various wirebooks I see AWG 20 and AWG 18 as wire to pin 6 (bus
voltage) on the LR-3's. For a 70 amp main and 20 amp secondary alternator
which combo is best:
24AWG Fuse link and 20 AWG?
or
22 AWG fuse link and 18 AWG?
Many Thanks,
John Schroeder.
--
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Alternator Field Wiring |
>
>
>Bob -
>
>Z-14. In various wirebooks I see AWG 20 and AWG 18 as wire to pin 6 (bus
>voltage) on the LR-3's. For a 70 amp main and 20 amp secondary alternator
>which combo is best:
>
>24AWG Fuse link and 20 AWG?
>or
>22 AWG fuse link and 18 AWG?
If the wire between bus and regulator is long (say over
6 feet) we'd like to minimize resistance . . . I'd
go 18/22 just for grins. Otherwise 20/24 is fine.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Fig Z-16 Rotax 912/914 System |
>
>
>Bob,
>
>You answered to Kinsley :
>
> > The wire from bus to breaker is more than 6" long and has
> > smoke-risk due to it's length an small size.
>
>On my MCR SPORTSTER (ROTAX 912 and Z-16), the line from terminal 5 on S1,
>Master Switch and the 5A CB is 2" long. The line from the 5A CB and the
>MAIN BUS is 4" long.
>Can I use 22AWG for the two line, without FuseLink ?
Sure
>I have seen some aircraft silicone sleeves to "protect" FastOn terminals.
>I use B&C ones. I never read anything about that on the Aeroelectric list.
>Usefull or useless ?
Looks purty . . . your option. I think heatshrink
would look better and would stay in place better.
>Thanks again for the job you do for us.
My pleasure sir.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
Subject: | Re: Quick connects |
In a message dated 1/30/2004 3:01:52 AM Eastern Standard Time,
dan(at)rvproject.com writes:
All of the suggestions given are good ones. The problem with using a
connector, though, is that if you need to remove the elevator, you'll have
to remove the connector...not convenient. (at least that's the way it is on
an RV...just a small round hole for the wire to pass through the elevator
spar)
Here's what I did instead:
http://www.rvproject.com/20040124.html
Hello Dan,
As an electronics professional, hobbyist and aviation nut, it is good to see
someone else finding some clever short cuts that I thought I owned in the
privacy of my shop 8
). Truthfully, many of us have used this "cheapest
connector" idea for some years. But, it is more than just cheap as you have pointed
out. It is a very small, reliable connection technique and if you stagger the
connection pins a bit, there is no smaller total diameter method that I know of
to connect a few wires in line for future easy disconnect.
Another advantage is the ease in making the actual connections-one at a time
in free space-not fighting to get to one pin in a nest of several. I also
like "Dean's Connectors" as someone else mentioned. Dean's connectors are small,
light, have very good contact pressures but they are a chore to solder the
wires to if you are our age. (let's just say over 40) The Dean's connectors
also suffer a diameter penalty in areas where that is an issue.
Back to D-sub pins again, I have epoxied female pins just inside of small
electronic goodies over the years. You drill a hole in the plastic shell of
whatever device and cement the female pin inside. Cables of just a few wires with
male pins connected and heat shrunk shielded are "plugged" in. Two holes in
the side of a plastic cased goody backed up with female pins can be jumpered
together with a "U" shaped pin where a function may be "jumpered" "out" or "in"
for different functions.
John P. Marzluf
Columbus, Ohio
Kitfox Outback (out back in the garage)
________________________________________________________________________________
From: | klehman(at)albedo.net |
Subject: | ov protection for internal v.r. alternators |
This is one of my remaining concerns as well. I'm using a different less
common small alternator and the internal v.r. for it happens to be a bit
expensive. I've seen several cautions regarding the requirement to have
a battery in the circuit to stabilize alternators. If it is unstable, I
can imagine excess voltage damaging the internal v.r. after the load is
disconnected. That makes me think that a switch (Bat Master/Alt.) to
allow disconnecting the ov relay while the engine is running may not be
a good idea. Likewise my concern about ov protection unless I can be
quite confident that no random erroneous disconnects are going to occur.
A real ov event is not a concern of course as in that event the internal
v.r. would almost certainly be already toasted.
Ken
>>>After talking to Vans, they said I probably blew the
>>>voltage regulator by switching off the field that
>>>disconnected the B-lead at the contactor. Switching
>>>off field after it has started doesn't stop the
>>>alternator because it gets field power from the
>>>B-lead. They said they've been seeing this a lot
>>>lately on alternators wired per z-24.
>>>
>>>Would it be an accurate statement to say that:
>>>"Turning off the alt field after it has been turned on
>>>for an internally regulated alternator wired as
>>>depicted in Z-24 is a death sentence for the
>>>alternator. An overvolt condition will also open the
>>>contactor and finish off the alternator for good."
>>>
>>>If so, this might be a handy piece of information to
>>>add to that diagram because it would have saved me
>>>some trouble.
>
> This is the first I've heard of it. Gee, if Van's
> has seen a rash of these events, it would have been
> really nice of them to let me know about it.
>
> I'm looking into this. Watch this space.
>
> Bob . . .
________________________________________________________________________________
From: | Clay R <clayr_55(at)yahoo.com> |
Subject: | re: ov protection for internal v.r. alternators |
Now I see the following warning on Vans web site on
the alternator page. (I think this was added this
week)
Warning!
The internally regulated 60 ampere alternator should
not be used with overvoltage protection systems. If
you open the charging circuit while it is in
operation, it will destroy the regulator.
-Clay
__________________________________
________________________________________________________________________________
From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
Bob,
" Unless your strobe supply has been sitting on the shelf for years,
that time honored slow crank-up procedure isn't really useful. It
was most useful 30 years ago before electrolytic capacitor technology
really came of age . . ."
Yeah, understood - 'cept the book that came with it says so, so
maybe I've been harbouring this since '97. Of course as you have so clearly
noted previously, manufacturers aren't ALWAYS right.............
Cheers, Ferg
________________________________________________________________________________
From: | "Ned Thomas" <315(at)cox.net> |
Subject: | Re: re: ov protection for internal v.r. alternators |
For what it is worth,
I had an internally regulated alternator on my RV6A. I had an Overvoltage
occur and had no way to shut it off except land and turn off the engine.
When I smelled the battery acid cooking out I was quite concerned. I was
able to land before ruining the battery but even tho I immediately turned
off the master when I found the voltmeter reading high, I did find that one
of my strobes had fried. After this happened I installled the OV protection
recommended by Bob. In the event you do encounter an OV situation you must
be able to isolate the alternator. I was lucky, the battery could have
blown up...
----- Original Message -----
From: "Clay R" <clayr_55(at)yahoo.com>
Subject: AeroElectric-List: re: ov protection for internal v.r. alternators
>
> Now I see the following warning on Vans web site on
> the alternator page. (I think this was added this
> week)
>
> Warning!
> The internally regulated 60 ampere alternator should
> not be used with overvoltage protection systems. If
> you open the charging circuit while it is in
> operation, it will destroy the regulator.
>
> -Clay
>
> __________________________________
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Quick connects |
>
>In a message dated 1/30/2004 3:01:52 AM Eastern Standard Time,
>dan(at)rvproject.com writes:
>All of the suggestions given are good ones. The problem with using a
>connector, though, is that if you need to remove the elevator, you'll have
>to remove the connector...not convenient. (at least that's the way it is on
>an RV...just a small round hole for the wire to pass through the elevator
>spar)
>
>Here's what I did instead:
>
>http://www.rvproject.com/20040124.html
>Hello Dan,
>
>As an electronics professional, hobbyist and aviation nut, it is good to see
>someone else finding some clever short cuts that I thought I owned in the
>privacy of my shop 8
>). Truthfully, many of us have used this "cheapest
>connector" idea for some years. But, it is more than just cheap as you
>have pointed
>out. It is a very small, reliable connection technique and if you stagger
>the
>connection pins a bit, there is no smaller total diameter method that I
>know of
>to connect a few wires in line for future easy disconnect.
>
>Another advantage is the ease in making the actual connections-one at a time
>in free space-not fighting to get to one pin in a nest of several. I also
>like "Dean's Connectors" as someone else mentioned. Dean's connectors are
>small,
>light, have very good contact pressures but they are a chore to solder the
>wires to if you are our age. (let's just say over 40) The Dean's connectors
>also suffer a diameter penalty in areas where that is an issue.
>
>Back to D-sub pins again, I have epoxied female pins just inside of small
>electronic goodies over the years. You drill a hole in the plastic shell of
>whatever device and cement the female pin inside. Cables of just a few
>wires with
>male pins connected and heat shrunk shielded are "plugged" in. Two holes in
>the side of a plastic cased goody backed up with female pins can be jumpered
>together with a "U" shaped pin where a function may be "jumpered" "out" or
>"in"
>for different functions.
Just one caution. When examining connectors classically
used in aircraft, one can see attention paid to protection
of the pin-socket joints and making sure that tension on
the wires won't open a joint. Unless you're working with
butt-splices, knife splices, and soldered joints, etc. where
resistance to tension are inherent in the technology, make
sure your quest for miniaturization and/or convenience doesn't
increased potential for failures that could make you
uncomfortable. I offered the d-sub pins and heat shrink
for compact thermocouple splicing . . . but then opening that
joint in flight doesn't affect flight system performance.
I don't intend to splash cold water on any innovative
techniques . . . only a word to the wise to think through
the failure mode effects analysis for any out-of-the-ordinary
usage of parts. Question: do you KNOW how difficult it is
to handle the airplane with a pitch trim actuator stuck at
either extreme? Of course this question goes to reliability
of ALL components in the pitch trim system, not just novel
approaches to miniature connectors.
Bob . . .
________________________________________________________________________________
From: | "Steve Sampson" <SSampson.SLN21(at)london.edu> |
Subject: | re: ov protection for internal v.r. alternators |
Clay - is anyone looking into this for you? It sounds like plenty of people
are getting blown alternators after putting the B&C stuff on. Steve.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Clay R
Subject: AeroElectric-List: re: ov protection for internal v.r.
alternators
Now I see the following warning on Vans web site on
the alternator page. (I think this was added this
week)
Warning!
The internally regulated 60 ampere alternator should
not be used with overvoltage protection systems. If
you open the charging circuit while it is in
operation, it will destroy the regulator.
-Clay
__________________________________
---
Incoming mail is certified Virus Free.
---
________________________________________________________________________________
From: | "Gary Casey" <glcasey(at)adelphia.net> |
Subject: | RE: Strain relief |
<>
That's exactly what I do, and I do that for the typical "Molex" connector as
well, since they don't have a particularly robust built-in strain relief.
Gary Casey
________________________________________________________________________________
From: | Clay R <clayr_55(at)yahoo.com> |
Subject: | RE: re: ov protection for internal v.r. alternators |
The cost to buy a 35A externally regulated alternator,
regulator, and bracket from another supplier was just
a little more than the cost to repair my Vans 60A
alternator ($70). So, that's what I did.
I still completely agree that there must be a way to
disconnect an internally regulated alternator from the
electrical system, and agree with Bob's advice there.
However, I don't like the fact that any trip of the OV
protection or the alt field switch will fry the
alternator. (or at least Vans alternator)
This is what it took to push me from the internally
regulated alternator that I already had, to an
externally regulated unit. I'm glad I found out about
this on the ground instead of at a later date.
The lesson learned is that I think this information
should be added to the wiring diagram for OV
protection so others will know about this limitation
too. (Vans has already added it to their web page,
and hopefully will add it to the instructions that
come with the alternator)
Right now, I'm planning on leaving the contactor in
place, even with the new externally regulated
alternator unless this isn't a good idea. (the only
possible downside I can think of is that the contactor
could fail and it really isn't necessary.) I WILL
test it though, to make sure the alternator stops
producing power when I turn off the Alt field switch.
All in all, this experience is just one more way we
all learn exactly how things electrical work in our
airplanes. I can tell you that after dealing with
this issue I REALLY know how the alternator and
charging system works, when I didn't before. I just
hope that sharing my experience leads to more
knowledge for others and safer planes for all to
follow.
Still looking forward to Bob's take on this too. (I
could still be wrong)
--Clay
Sampson"
Clay - is anyone looking into this for you? It sounds
like plenty of people
are getting blown alternators after putting the B&C
stuff on. Steve.
__________________________________
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | RE: OV protection for internally regulated alternators |
As promised, I've been looking into this problem and I've crafted
a white paper on the topic. Here is the text of the paper . . .
-------------------------------------------
"Load Dump" Damage to Alternators with Built-in Regulators
Bob Nuckolls
1 February 2004
>AeroElectric-List message posted by: "Ned Thomas" <315(at)cox.net>
>
>For what it is worth, I had an internally regulated alternator
>on my RV6A. I had an overvoltage occur and had no way to
>shut it off except land and turn off the engine. When
>I smelled the battery acid cooking out I was quite concerned.
>I was able to land before ruining the battery but even tho
>I immediately turned off the master when I found the
>voltmeter reading high, I did find that one of my strobes
>had fried. After this happened I installed the OV protection
>recommended by Bob. In the event you do encounter an OV
>situation you must be able to isolate the alternator.
>I was lucky, the battery could have blown up...
>----- Original Message -----
>From: "Clay R" <clayr_55(at)yahoo.com>
>Now I see the following warning on Vans web site on
>the alternator page. (I think this was added this week)
>Warning!
>The internally regulated 60 ampere alternator should not
>be used with overvoltage protection systems. If you
>open the charging circuit while it is in operation,
>it will destroy the regulator.
>AeroElectric-List message posted by: "Steve Sampson"
Clay - is anyone looking into this for you? It sounds
>like plenty of people are getting blown alternators
>after putting the B&C stuff on.
BACKGROUND
(1) The "B&C stuff" is only a collection of parts described in documents
described in the AeroElectric Connection. Let us take care as to how the
phenomenon is described with respect to implied cause and effect. It's not
B&C's architecture but AeroElectric Connection architecture . . . B&C only
sells the parts to implement it.
(2) For years and since day-one of my participation in B&C's development
and marketing of alternators, we have preached the doctrine of externally
regulated alternators. Examples of this philosophy are found throughout
early writings and particularly in chapters on alternators and regulators
in the 'Connection. A simple inspection of B&C's offerings from the
beginning will show that only externally regulated alternators are offered.
(3) There has been a lot of interest in adapting internally regulated
alternators to aircraft because they are so readily available and cheap.
Further, they've produced an excellent track record of reliability on cars
. . . it seems a shame not exploit that characteristic in aircraft.
(4) The challenge for adapting internally regulated alternators to
airplanes has always been making them behave like externally regulated
alternators and generators before them. On the instrument panel there is a
switch labeled ALT OFF/ON. One expects that operation of this switch will
produce the same result whether you're sitting in a 1965 C-172 or a 2004 RV-8.
(5) Most alternators with built in regulators, once given the ON command
via the rear-connected control wire will indeed come alive . . . but since
this wire was originally intended only as a means for the EFI controller on
a car to delay onset of engine loads after starting, there was no
requirement for being able to turn the alternator OFF via this same wire.
So, the vast majority of automotive take-offs cannot be turned OFF by
removing +14v from the control wire via panel mounted switch. This
condition was experienced by Mr. Thomas in the anecdote cited earlier.
(6) While the probability of regulator failure in cars is exceedingly low,
it is not zero. We've heard anecdotal stories of unhappy, high-dollar
events taking place in airplanes after failure of an internally regulated
alternator.
(7) With the goal of addressing a desire in the marketplace to utilize
off-the-car technology, figure Z-24 was developed to address both
controllability and overvoltage issues with the lowest practical parts
count and without modifying the alternator.
RECENT HISTORY
It seems that there have been a rash of failures of internally regulated
alternators installed per Figure Z-24. Let's review the inner workings and
shortcomings of the modern, internally regulated alternators. We know that
all alternators run best with a battery connected across their output. The
battery is an excellent filter for the noise inherent on DC power generated
by rectified 3-phase AC power. The battery also provides a flywheel effect
. . . a kind of electrical inertia that damps out the frisky nature of an
alternator's ability to quicky respond to and control its own output.
A phenomenon labeled by the automotive industry as "load dump" speaks to a
characteristic native to the physics of alternator performance. Its
existence has been known since the beginnings of alternator use in
vehicles . . . but it was only a concern after a proliferation of solid
state electronics for fuel injection systems, ignition systems, anti-lock
brakes, etc. Should an alternator producing a lot of power be suddenly
disconnected from the load, it may generate what would be properly called a
surge of voltage exceeding bus voltage by several times. If the load dump
is limited to shedding of normal system loads, the battery's electrical
inertia will be in place to smooth over the event. However, if the
disconnection includes the battery, no mitigating electrical-mass is
present to capture a significant energy transient. In aviation parlance,
a "load dump" is rapid shedding of normal system loads. The scenario we are
discussing might be more appropriately called a "battery dump".
Unlike relatively low energy spikes characteristic of switching transients
on inductive loads, a battery dump event is longer and carries a lot more
energy. In the spring of 1998, there was a romance in the OBAM aircraft
community with products called transient voltage suppressors (TVS). A
school of thought suggested that the electrical system be sprinkled with
these little critters to ward off effects of any gremlins of the
overvoltage persuasion which may be lurking about the system. The suggested
technique was to install a TVS on the power feeder for each vulnerable
accessory.
There was an extensive discussion thread. You may review published excerpts
of that discussion at:
http://aeroelectric.com/articles/spike.pdf
This was before we began to consider and refine any notions of using
internally regulated alternators in OBAM aircraft.
In that thread, I suggested it was much better to (1) identify and mitigate
such hazards at their source and/or (2) design accessories to be immune to
such hazards. For decades, DO-160 has been an effective guideline for
development of robust victims while MIL-STD-704 outlined design goals for
output quality of power generation equipment.
Here are but a few of hundreds of relevant documents on the phenomenon to
be found on the web . . .
http://www.sto-p.com/pfp/pfp-transients.htm
http://www.onsemi.com/pub/Collateral/CS3341-D.PDF
http://www.audifans.com/archives/1998/08/msg00929.html
. . . do a Google search on "load dump" and "alternator" for a wealth of
useful expansion of the topic.
WHAT'S HAPPENING?
The original discussions 4 years ago focused on the need to protect system
accessories from the effects of alternator behavior. In the cases before us
now, the victim is NOT airframe system accessories being hammered by a
skittish alternator. These are cases where the alternator is killing itself
. . . or more accurately, killing its own voltage regulator.
If you look over the specifications for modern, solid state regulator
chips, you'll find references to protection against load dump conditions
built right onto the chip. I believe what we're observing now is a
shortcoming of relatively mature automotive take-off alternators with
regulators that do not enjoy this kind of protection.
Referring to the group of block diagrams in this document, note that I've
illustrated 4 configurations of installation architecture for alternators
with built in regulators.
(download
http://www.aeroelectric.com/articles/Alternator_Failures.pdf
to get the illustration)
(1) The first diagram is captioned "AUTOMOTIVE" and it illustrates the
relationship between battery and alternator in virtually all automotive
applications. The battery is ALWAYS connected to the alternator. System
loads are controlled via panel switches and/or ignition switch but portions
of the power distribution system are always hot, even when the vehicle is
parked. Not desirable on airplanes.
(2) The second configuration is "FIGURE Z-24" referring to an architecture
described in the AeroElectric Connection to accommodate two hard-and-fast
design goals for using an alternator in an airplane: (a) absolute control
of the alternator operation from the cockpit irrespective of flight
condition and (b) protection against the very rare but potentially
hazardous and expensive overvoltage condition.
(3) The third configuration describes an ill-conceived recommendation
suggesting deletion of the alternator disconnect and wiring the alternator
to the airplane a-la-automotive. Note that while this configuration
prevents the pilot from switching an alternator off while in operation, it
does not prevent the battery from being taken off line. If we
disconnect the alternator from the system while leaving the battery on as
allowed with Figure Z-24, only the alternator is at-risk for self destruction.
When you leave the alternator connected to the system and shut off the
battery master, there is still risk of a battery-dump transient. While
system loads will soak up some transient energy and mitigate amplitude and
duration of the event, now the whole system is subjected to the transient.
In airplanes like the Baron and Bonanza where alternators and battery
master switches are separate, non-interlocked controls, switches can be
manipulated in a manner that will produce the same "battery dump" effect
that we're discussing. So the potential for this effect is not new nor is
it unique to the nifty little alternators so popular in the OBAM aircraft
community.
(4) The fourth configuration illustrates an experiment to be conducted
which may prove the usefulness of a technique intended to tame the dragon.
A PROPOSED GAME PLAN
(1) If you have Figure Z-24 installed and you're already flying or nearly
ready to fly, don't change anything. Although you may never need the
protections Z-24 offers, I don't recommend you go flying without it. It is
EASY to prevent battery dump damage to the alternator by controlling
sequence of operation for the switches.
[a] Battery master is the first switch to come on before cranking the
engine and it should stay on until after engine shutdown.
[b] The alternator control switch may be turned on before cranking the
engine but it's probably better to leave it off until after the engine is
running.
[c] At the end of the flight, shut the engine down before first turning
off the alternator . . . .
[d] . . . followed by turning of the battery master switch.
Following suggestions in any of the Z-figures in the 'Connection will
provide you with interlocked battery master and alternator control switches
wired so as to prevent an alternator from remaining on-line with the
battery disconnected.
The battery dump transient is generated by the disconnection of the battery
from the alternator b-lead terminal while the alternator is working hard.
It can't be working hard if the engine is not running. The warning
published by Van's is accurate as far as it goes but misses important
points with respect to absolute operational control of the alternator from
the cockpit and overvoltage protection. So, if you don't diddle with the
switch while the engine is running, your alternator is not at risk for
battery dump damage and you retain both operational control and overvoltage
protection.
(2) If you have yet to select an alternator but need to do it soon, you
cannot go wrong with installing an alternator designed for aircraft
service. Alternators using external regulation are easily managed for both
operational control and overvoltage protection by simply opening the field
lead. This activity does not generate the battery dump transient we're
discussing.
(3) I'm planning to test an alternator with built in regulation on a test
stand using a fat TVS device connected as shown in the last block diagram.
I'll be making measurements of worst-case transient energies and making
sure that the diode we select is adequately sized to the task.
NOTE
If anyone out there remembers the zener diode
that Pelican Aviation used to stick on the back
side of their alternators (some STC'd no less!)
while calling it "overvoltage protection" please
recall that this was neither ov protection nor
was it a practical solution to the problem
before us now.
After the bench testing studies are complete, I'll be looking for
volunteers who are already flying Figure Z-24 alternator control schemes. I
will supply a pair of TVS diodes for installation on your airplane. You
will be asked to conduct a series of battery dump simulations. After the
simulations, you'll be asked to install the second diode and return the
first one to me for inspection.
Once we've done the repeatable experiment to demonstrate suitability of the
"fix", this paper will be updated to publish the results and Figure Z-24
will be updated appropriately. In the mean time, I'll supply a copy of this
paper to Van's in with the hope that it will clarify the issues and
forestall some poorly founded modifications to electrical systems in the
OBAM aircraft community. Please feel free to circulate this document for
both its informative value and potential for critical review.
As a closing note to this document, I ran across this paper:
http://www.st.com/stonline/books/pdf/docs/4345.pdf
. . . written by the folks at SGS-Thompson on battery dump mitigation. This
paper describes a proposed technique for building battery dump management
right into the alternator . . . what a concept! Whether or not this
capability will be offered in automotive products suited to airplanes soon
is hard to predict. In the meantime, it's a no-brainer to make the
alternators we have work quite nicely.
The bottom line folks . . . I believe there is good value in the use of
internally regulated alternators on airplanes. However, it's important that
we make decisions based upon good science that helps us understand and
accommodate their unique characteristics.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | OV protection for alternators with built in regulators |
I'm told that a warning notice has been published on Van's
website concerning damage to alternators having built
in regulators that are wired per Figure Z-24 in the
AeroElectric Connection.
I've researched the problem and crafted a white paper
outlining history and technical details of the phenomenon
along with an interim work-around plus plans for development
of a permanent fix.
You're welcome to download the paper at
http://www.aeroelectric.com/articles/Alternator_Failures.pdf
Feel free to link to, or re-publish all or any part of this
document as you see fit to service your customers.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | Matt Jurotich <mjurotich(at)hst.nasa.gov> |
Subject: | SD-8 and meltdowns |
Bob and All
I have been watching for the story on the SD-8 and meltdown of the external
regulator. Did I miss it or we don't have info yet? I thought Bob said he
was going to do some experiments.
Thanks
Matthew M. Jurotich
NASA/Goddard Space Flight Center
Swales contractor to the
JWST ISIM Systems Engineer
m/c : 443
e-mail mail to:
phone : 301-286-5919
fax : 301-286-1736
JWST URL: <http://ngst1.gsfc.nasa.gov
________________________________________________________________________________
From: | "John Livingston" <livingjw(at)earthlink.net> |
Subject: | Re: RE: OV protection for internally regulated alternators |
Bob,
If I have a progressive battery/alternator switch can I still get into
trouble if I quickly slam it totally off instead of taking the alternator
off line, pause then turn off the battery? I can see how this might happen
during an incident, if, for instance, one smelled smoke in the cockpit. Is
this one senerio of concern?
John
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: AeroElectric-List: RE: OV protection for internally regulated
alternators
>
> As promised, I've been looking into this problem and I've crafted
> a white paper on the topic. Here is the text of the paper . . .
>
> -------------------------------------------
> "Load Dump" Damage to Alternators with Built-in Regulators
>
> Bob Nuckolls
> 1 February 2004
>
> >AeroElectric-List message posted by: "Ned Thomas" <315(at)cox.net>
> >
> >For what it is worth, I had an internally regulated alternator
> >on my RV6A. I had an overvoltage occur and had no way to
> >shut it off except land and turn off the engine. When
> >I smelled the battery acid cooking out I was quite concerned.
> >I was able to land before ruining the battery but even tho
> >I immediately turned off the master when I found the
> >voltmeter reading high, I did find that one of my strobes
> >had fried. After this happened I installed the OV protection
> >recommended by Bob. In the event you do encounter an OV
> >situation you must be able to isolate the alternator.
> >I was lucky, the battery could have blown up...
>
> >----- Original Message -----
> >From: "Clay R" <clayr_55(at)yahoo.com>
>
> >Now I see the following warning on Vans web site on
> >the alternator page. (I think this was added this week)
>
> >Warning!
>
> >The internally regulated 60 ampere alternator should not
> >be used with overvoltage protection systems. If you
> >open the charging circuit while it is in operation,
> >it will destroy the regulator.
>
> >AeroElectric-List message posted by: "Steve Sampson"
>
>
> Clay - is anyone looking into this for you? It sounds
> >like plenty of people are getting blown alternators
> >after putting the B&C stuff on.
>
> BACKGROUND
>
> (1) The "B&C stuff" is only a collection of parts described in documents
> described in the AeroElectric Connection. Let us take care as to how the
> phenomenon is described with respect to implied cause and effect. It's not
> B&C's architecture but AeroElectric Connection architecture . . . B&C only
> sells the parts to implement it.
>
> (2) For years and since day-one of my participation in B&C's development
> and marketing of alternators, we have preached the doctrine of externally
> regulated alternators. Examples of this philosophy are found throughout
> early writings and particularly in chapters on alternators and regulators
> in the 'Connection. A simple inspection of B&C's offerings from the
> beginning will show that only externally regulated alternators are
offered.
>
> (3) There has been a lot of interest in adapting internally regulated
> alternators to aircraft because they are so readily available and cheap.
> Further, they've produced an excellent track record of reliability on cars
> . . . it seems a shame not exploit that characteristic in aircraft.
>
> (4) The challenge for adapting internally regulated alternators to
> airplanes has always been making them behave like externally regulated
> alternators and generators before them. On the instrument panel there is a
> switch labeled ALT OFF/ON. One expects that operation of this switch will
> produce the same result whether you're sitting in a 1965 C-172 or a 2004
RV-8.
>
> (5) Most alternators with built in regulators, once given the ON command
> via the rear-connected control wire will indeed come alive . . . but since
> this wire was originally intended only as a means for the EFI controller
on
> a car to delay onset of engine loads after starting, there was no
> requirement for being able to turn the alternator OFF via this same wire.
> So, the vast majority of automotive take-offs cannot be turned OFF by
> removing +14v from the control wire via panel mounted switch. This
> condition was experienced by Mr. Thomas in the anecdote cited earlier.
>
> (6) While the probability of regulator failure in cars is exceedingly low,
> it is not zero. We've heard anecdotal stories of unhappy, high-dollar
> events taking place in airplanes after failure of an internally regulated
> alternator.
>
> (7) With the goal of addressing a desire in the marketplace to utilize
> off-the-car technology, figure Z-24 was developed to address both
> controllability and overvoltage issues with the lowest practical parts
> count and without modifying the alternator.
>
> RECENT HISTORY
>
> It seems that there have been a rash of failures of internally regulated
> alternators installed per Figure Z-24. Let's review the inner workings and
> shortcomings of the modern, internally regulated alternators. We know that
> all alternators run best with a battery connected across their output. The
> battery is an excellent filter for the noise inherent on DC power
generated
> by rectified 3-phase AC power. The battery also provides a flywheel
effect
> . . . a kind of electrical inertia that damps out the frisky nature of an
> alternator's ability to quicky respond to and control its own output.
>
> A phenomenon labeled by the automotive industry as "load dump" speaks to a
> characteristic native to the physics of alternator performance. Its
> existence has been known since the beginnings of alternator use in
> vehicles . . . but it was only a concern after a proliferation of solid
> state electronics for fuel injection systems, ignition systems, anti-lock
> brakes, etc. Should an alternator producing a lot of power be suddenly
> disconnected from the load, it may generate what would be properly called
a
> surge of voltage exceeding bus voltage by several times. If the load dump
> is limited to shedding of normal system loads, the battery's electrical
> inertia will be in place to smooth over the event. However, if the
> disconnection includes the battery, no mitigating electrical-mass is
> present to capture a significant energy transient. In aviation parlance,
> a "load dump" is rapid shedding of normal system loads. The scenario we
are
> discussing might be more appropriately called a "battery dump".
>
> Unlike relatively low energy spikes characteristic of switching transients
> on inductive loads, a battery dump event is longer and carries a lot more
> energy. In the spring of 1998, there was a romance in the OBAM aircraft
> community with products called transient voltage suppressors (TVS). A
> school of thought suggested that the electrical system be sprinkled with
> these little critters to ward off effects of any gremlins of the
> overvoltage persuasion which may be lurking about the system. The
suggested
> technique was to install a TVS on the power feeder for each vulnerable
> accessory.
>
> There was an extensive discussion thread. You may review published
excerpts
> of that discussion at:
>
> http://aeroelectric.com/articles/spike.pdf
>
> This was before we began to consider and refine any notions of using
> internally regulated alternators in OBAM aircraft.
>
> In that thread, I suggested it was much better to (1) identify and
mitigate
> such hazards at their source and/or (2) design accessories to be immune to
> such hazards. For decades, DO-160 has been an effective guideline for
> development of robust victims while MIL-STD-704 outlined design goals for
> output quality of power generation equipment.
>
> Here are but a few of hundreds of relevant documents on the phenomenon to
> be found on the web . . .
>
> http://www.sto-p.com/pfp/pfp-transients.htm
>
> http://www.onsemi.com/pub/Collateral/CS3341-D.PDF
>
> http://www.audifans.com/archives/1998/08/msg00929.html
>
> . . . do a Google search on "load dump" and "alternator" for a wealth of
> useful expansion of the topic.
>
> WHAT'S HAPPENING?
>
> The original discussions 4 years ago focused on the need to protect system
> accessories from the effects of alternator behavior. In the cases before
us
> now, the victim is NOT airframe system accessories being hammered by a
> skittish alternator. These are cases where the alternator is killing
itself
> . . . or more accurately, killing its own voltage regulator.
>
> If you look over the specifications for modern, solid state regulator
> chips, you'll find references to protection against load dump conditions
> built right onto the chip. I believe what we're observing now is a
> shortcoming of relatively mature automotive take-off alternators with
> regulators that do not enjoy this kind of protection.
>
> Referring to the group of block diagrams in this document, note that I've
> illustrated 4 configurations of installation architecture for alternators
> with built in regulators.
>
> (download
>
> http://www.aeroelectric.com/articles/Alternator_Failures.pdf
>
> to get the illustration)
>
> (1) The first diagram is captioned "AUTOMOTIVE" and it illustrates the
> relationship between battery and alternator in virtually all automotive
> applications. The battery is ALWAYS connected to the alternator. System
> loads are controlled via panel switches and/or ignition switch but
portions
> of the power distribution system are always hot, even when the vehicle is
> parked. Not desirable on airplanes.
>
> (2) The second configuration is "FIGURE Z-24" referring to an architecture
> described in the AeroElectric Connection to accommodate two hard-and-fast
> design goals for using an alternator in an airplane: (a) absolute control
> of the alternator operation from the cockpit irrespective of flight
> condition and (b) protection against the very rare but potentially
> hazardous and expensive overvoltage condition.
>
> (3) The third configuration describes an ill-conceived recommendation
> suggesting deletion of the alternator disconnect and wiring the
alternator
> to the airplane a-la-automotive. Note that while this configuration
> prevents the pilot from switching an alternator off while in operation,
it
> does not prevent the battery from being taken off line. If we
> disconnect the alternator from the system while leaving the battery on
as
> allowed with Figure Z-24, only the alternator is at-risk for self
destruction.
>
> When you leave the alternator connected to the system and shut off the
> battery master, there is still risk of a battery-dump transient. While
> system loads will soak up some transient energy and mitigate amplitude and
> duration of the event, now the whole system is subjected to the transient.
>
> In airplanes like the Baron and Bonanza where alternators and battery
> master switches are separate, non-interlocked controls, switches can be
> manipulated in a manner that will produce the same "battery dump" effect
> that we're discussing. So the potential for this effect is not new nor is
> it unique to the nifty little alternators so popular in the OBAM aircraft
> community.
>
> (4) The fourth configuration illustrates an experiment to be conducted
> which may prove the usefulness of a technique intended to tame the dragon.
>
> A PROPOSED GAME PLAN
>
> (1) If you have Figure Z-24 installed and you're already flying or nearly
> ready to fly, don't change anything. Although you may never need the
> protections Z-24 offers, I don't recommend you go flying without it. It
is
> EASY to prevent battery dump damage to the alternator by controlling
> sequence of operation for the switches.
>
> [a] Battery master is the first switch to come on before cranking the
> engine and it should stay on until after engine shutdown.
>
> [b] The alternator control switch may be turned on before cranking the
> engine but it's probably better to leave it off until after the engine is
> running.
>
> [c] At the end of the flight, shut the engine down before first turning
> off the alternator . . . .
>
> [d] . . . followed by turning of the battery master switch.
>
> Following suggestions in any of the Z-figures in the 'Connection will
> provide you with interlocked battery master and alternator control
switches
> wired so as to prevent an alternator from remaining on-line with the
> battery disconnected.
>
> The battery dump transient is generated by the disconnection of the
battery
> from the alternator b-lead terminal while the alternator is working hard.
> It can't be working hard if the engine is not running. The warning
> published by Van's is accurate as far as it goes but misses important
> points with respect to absolute operational control of the alternator from
> the cockpit and overvoltage protection. So, if you don't diddle with the
> switch while the engine is running, your alternator is not at risk for
> battery dump damage and you retain both operational control and
overvoltage
> protection.
>
> (2) If you have yet to select an alternator but need to do it soon, you
> cannot go wrong with installing an alternator designed for aircraft
> service. Alternators using external regulation are easily managed for both
> operational control and overvoltage protection by simply opening the field
> lead. This activity does not generate the battery dump transient we're
> discussing.
>
> (3) I'm planning to test an alternator with built in regulation on a test
> stand using a fat TVS device connected as shown in the last block diagram.
> I'll be making measurements of worst-case transient energies and making
> sure that the diode we select is adequately sized to the task.
>
> NOTE
>
> If anyone out there remembers the zener diode
> that Pelican Aviation used to stick on the back
> side of their alternators (some STC'd no less!)
> while calling it "overvoltage protection" please
> recall that this was neither ov protection nor
> was it a practical solution to the problem
> before us now.
>
> After the bench testing studies are complete, I'll be looking for
> volunteers who are already flying Figure Z-24 alternator control schemes.
I
> will supply a pair of TVS diodes for installation on your airplane. You
> will be asked to conduct a series of battery dump simulations. After the
> simulations, you'll be asked to install the second diode and return the
> first one to me for inspection.
>
> Once we've done the repeatable experiment to demonstrate suitability of
the
> "fix", this paper will be updated to publish the results and Figure Z-24
> will be updated appropriately. In the mean time, I'll supply a copy of
this
> paper to Van's in with the hope that it will clarify the issues and
> forestall some poorly founded modifications to electrical systems in the
> OBAM aircraft community. Please feel free to circulate this document for
> both its informative value and potential for critical review.
>
> As a closing note to this document, I ran across this paper:
>
> http://www.st.com/stonline/books/pdf/docs/4345.pdf
>
> . . . written by the folks at SGS-Thompson on battery dump mitigation.
This
> paper describes a proposed technique for building battery dump management
> right into the alternator . . . what a concept! Whether or not this
> capability will be offered in automotive products suited to airplanes soon
> is hard to predict. In the meantime, it's a no-brainer to make the
> alternators we have work quite nicely.
>
> The bottom line folks . . . I believe there is good value in the use of
> internally regulated alternators on airplanes. However, it's important
that
> we make decisions based upon good science that helps us understand and
> accommodate their unique characteristics.
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Dan Checkoway" <dan(at)rvproject.com> |
Subject: | trick for combing out shield? |
Is there any slick trick for combing out braided shielding more easily?
Case in point, RG-400 with its double layer of shielding.
)_( Dan
RV-7 N714D
http://www.rvproject.com
________________________________________________________________________________
Subject: | My Jabiru J400 made test flights, |
From: | "Scott, Ian" <ian_scott(at)commander.com> |
Last Sunday the my Jabiru J400 did its first test flight and a subsequent flight
of a few hours, all was good, and all the smoke stayed in the wires.
Elevated CHT due to the new engine, all the rest good and nearly 2000Fpm climb,
man this is a rocket.
Ian
________________________________________________________________________________
From: | "David Carter" <dcarter(at)datarecall.net> |
Subject: | Fw: RV-List: RE: Dynon EMI (different scenario) |
This interesting thread on the RV-list probaly has a place on the
Aeroelectric list, also, in case some players aren't monitoring both.
David
----- Original Message -----
From: "Kevin Behrent" <kbehrent(at)cascadiasoftware.com>
Subject: Re: RV-List: RE: Dynon EMI (different scenario)
> --> RV-List message posted by: Kevin Behrent
>
> "Paul Boyce, Ph.D." wrote:
>
> > --> RV-List message posted by: "Paul Boyce, Ph.D."
<matronicspost@csg-i.com>
> >
> > There's a couple of very disappointing things about this situation:
> >
> > 1) in a total electric failure emergency, my backup handheld radio will
most
> > likely be rendered useless.
> >
> > 2) in an otherwise excellent product, those engineering folks at Dynon
have
> > completely dropped the ball in not doing thorough Quality Control checks
on
> > EMI. Isn't it obvious that in a highly electrified environment such as
an
> > airplane cockpit, one MUST check for EMI? Is that too much to ask?
> >
> > I will be giving them a call tomorrow.
> >
> > Paul
> >
>
> One possible reason why some people are having "noticeable" EMI
interference
> and others don't is the quaility and vintage of radio(s) that they have
> installed.
>
> I say this because I have experienced this when I had a complete panel
upgrade
> on my Mooney where a complete Garmin stack was put in, but I retained my
old,
> trusty, Narco Mark 12D+/DME. The GNS430 and the Narco constantly
interfered with
> each other and both units were sent back to the respective factory on
multiple
> occassions. What was finally determined, by both manufactures, was noise
> filtering capability on both units. The 430 does a pretty good in pre/post
> filtering so that the large LCD panel would not interfere with "newer"
avionics.
> The Narco, on the other hand, has little pre filtering, thus is very
reactive to
> the lcd screen. It also emits it's own share of emi that the 430 tries to
> handle, but fails when conditions are right. The solution, however
exceptable
> but not perfect, was shielding everything, and doing some rework on the
radio
> trays to help shield.
>
> The lesson I learned was not to mix new new with old. For what it cost to
> minimize the problem, I could have purchased a second 430.
>
> We had the President of Dynon speak at our January EAA monthly meeting and
I can
> say that he and his engineers are very bright people and they will find a
way to
> reduce or eliminate the problem. On the other hand, LCD screens will
always
> emit a certain level of radiation that older generation of radios do not
> filter. As glass panels evolve, so does radio filtering. However, don't
expect
> that your radio(s) are properly filtered to guard againt these emissions.
>
> It would be interesting to study the type of avionics being used by both
groups
> and see if there are any similarities.
>
>
> Kevin Behrent
> RV-9A - Wings
> EAA 326, President
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: DIY audio amp |
>Bob:
>
>I am building your stereo audio mixer and had questions:
>
>http://www.aeroelectric.com/Catalog/AEC/9009/9009-700D.pdf
>
>The schematic shows resistor R101, 102, 108 but there are no places for
>them on the etched circuit board. Where do I put them?
>
>Where do the input resistors R104, 105, 106, 107 go? Do they go across the
>header jumpers?
Sorry to take so long to get back with you on this. Seems
revision D of the assembly document was missing a parts
locator figure. I've repaired the omission and published
revision E at:
http://www.aeroelectric.com/Catalog/AEC/9009/9009-700E.pdf
You are correct, those parts are on the header.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: SD-8 and meltdowns |
>
>
>Bob and All
>
>I have been watching for the story on the SD-8 and meltdown of the external
>regulator. Did I miss it or we don't have info yet? I thought Bob said he
>was going to do some experiments.
I've got the regulator in-hand . . . too many irons in
the fire to do the study this week. I'm getting ready
for the KC seminar next weekend.
Perhaps next week.
Bob . . .
________________________________________________________________________________
Subject: | Re: trick for combing out shield? |
In a message dated 2/2/2004 10:22:24 PM Eastern Standard Time,
dan(at)rvproject.com writes:
Is there any slick trick for combing out braided shielding more easily?
Case in point, RG-400 with its double layer of shielding.
)_( Dan
RV-7 N714D
http://www.rvproject.com
Dan,
I have always used a scribe for the task. It is best to not get too greedy,
but comb out a short section at a time, working back towards the root. A
large needle is a good substitute for the scribe. With all strands parallel, the
connector will have the best, uniform bite.
John P. Marzluf
Columbus, Ohio
Kitfox Outback (out back in the garage)
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: trick for combing out shield? |
>
>In a message dated 2/2/2004 10:22:24 PM Eastern Standard Time,
>dan(at)rvproject.com writes:
>Is there any slick trick for combing out braided shielding more easily?
>Case in point, RG-400 with its double layer of shielding.
Why comb it out? If you want to make connections to
double shields like RG-400 coax, it's probably better
to trim the shields just as if you were going to install
a crimp on connector. Then wrap the exposed shield with
a piece of braid and solder it. This is a modification
of the technique shown in:
http://www.aeroelectric.com/articles/pigtail/pigtail.html
For wires with single shields, try the technique shown here:
http://www.aeroelectric.com/articles/shldwire/shldwire.html
This might even work with double shielded wire like RG-400,
I've not tried it.
In any case, I think you'll be more pleased with the outcome
if you don't un-braid the strands. Doing that tends to produce
a finished termination that looks like it's having a bad
hair day.
Bob
________________________________________________________________________________
From: | DWENSING(at)aol.com |
Subject: | Re: trick for combing out shield? |
In a message dated 2/2/04 10:22:24 PM Eastern Standard Time,
dan(at)rvproject.com writes:
> Is there any slick trick for combing out braided shielding more easily?
> Case in point, RG-400 with its double layer of shielding.
>
I use a crochet hook. It has a small very smooth hook that works great and
does not damage the shield wires if done gently. You can purchase at your local
fabric store.
Dale Ensing
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Dynon EMI (different scenario) |
Hmmm, funny this should pop up right now in the OBAM aircraft
community . . . Just yesterday, I was invited to work a project
involving players I won't name but suffice it to say that there
are some aspects of the current crop of flat panel displays that
are needing closer examination.
In some cases, the antagonist flight instrument does meed
DO-160 emissions requirements but the frequencies of interest
are so stable and coherent as to offer some problems (albeit
small ones) to radio receivers on the airplane. Other aspects
of radiation discovered exceed DO-160 requirements and are
broad band noises that degrade performance of other systems.
Be advised that this problem is not unique to the low-dollar
players. If I learn something of this situation that can be
shared in terms of the simple-ideas, I'll share it with the
List.
With respect to the anecdotes cited below: The builder might
get acceptable if not completely quiet performance from the
hand-held by connecting it to an external antenna remote as
practical from the cockpit.
It's true that older radios were NOT explored for their
vulnerabilities to broad band noises typical of microprocessor
based electronics. If you have one of those battery powered
short wave receivers, try exploring the environment around
your desktop or laptop computer over the short wave frequencies.
This is why computers have the sticker on them that states
while they're qualified under FCC Part 15 rules for total
emissions, they MIGHT still interfere with other radio
based systems. In these cases, it is incumbent upon the
operator of the antagonist to modify the situation to
favor the victim.
It's unfortunate that many developmental tasks are not
fully understood until AFTER a product hits the marketplace.
The designers and testers cannot anticipate EVERY installation
variable. It's seldom reflects on the ability or integrity
of the designers, only in the discovery of NEW questions
not asked and answered before the product hit the field.
Bob . . .
---------- Original Message -----------------------------
>
>
>This interesting thread on the RV-list probaly has a place on the
>Aeroelectric list, also, in case some players aren't monitoring both.
>
>David
>
>----- Original Message -----
>From: "Kevin Behrent" <kbehrent(at)cascadiasoftware.com>
>To:
>Subject: Re: RV-List: RE: Dynon EMI (different scenario)
>
>
> > --> RV-List message posted by: Kevin Behrent
>
> >
> > "Paul Boyce, Ph.D." wrote:
> >
> > > --> RV-List message posted by: "Paul Boyce, Ph.D."
><matronicspost@csg-i.com>
> > >
> > > There's a couple of very disappointing things about this situation:
> > >
> > > 1) in a total electric failure emergency, my backup handheld radio will
>most
> > > likely be rendered useless.
> > >
> > > 2) in an otherwise excellent product, those engineering folks at Dynon
>have
> > > completely dropped the ball in not doing thorough Quality Control checks
>on
> > > EMI. Isn't it obvious that in a highly electrified environment such as
>an
> > > airplane cockpit, one MUST check for EMI? Is that too much to ask?
> > >
> > > I will be giving them a call tomorrow.
> > >
> > > Paul
> > >
> >
> > One possible reason why some people are having "noticeable" EMI
>interference
> > and others don't is the quaility and vintage of radio(s) that they have
> > installed.
> >
> > I say this because I have experienced this when I had a complete panel
>upgrade
> > on my Mooney where a complete Garmin stack was put in, but I retained my
>old,
> > trusty, Narco Mark 12D+/DME. The GNS430 and the Narco constantly
>interfered with
> > each other and both units were sent back to the respective factory on
>multiple
> > occassions. What was finally determined, by both manufactures, was noise
> > filtering capability on both units. The 430 does a pretty good in pre/post
> > filtering so that the large LCD panel would not interfere with "newer"
>avionics.
> > The Narco, on the other hand, has little pre filtering, thus is very
>reactive to
> > the lcd screen. It also emits it's own share of emi that the 430 tries to
> > handle, but fails when conditions are right. The solution, however
>exceptable
> > but not perfect, was shielding everything, and doing some rework on the
>radio
> > trays to help shield.
> >
> > The lesson I learned was not to mix new new with old. For what it cost to
> > minimize the problem, I could have purchased a second 430.
> >
> > We had the President of Dynon speak at our January EAA monthly meeting and
>I can
> > say that he and his engineers are very bright people and they will find a
>way to
> > reduce or eliminate the problem. On the other hand, LCD screens will
>always
> > emit a certain level of radiation that older generation of radios do not
> > filter. As glass panels evolve, so does radio filtering. However, don't
>expect
> > that your radio(s) are properly filtered to guard againt these emissions.
> >
> > It would be interesting to study the type of avionics being used by both
>groups
> > and see if there are any similarities.
________________________________________________________________________________
From: | "Dan Checkoway" <dan(at)rvproject.com> |
Subject: | Re: trick for combing out shield? |
Bob,
I would have much preferred to do that. That's what I usually do on
non-coax shielded wire. But a while back I read somewhere (this list, I
believe) that you shouldn't use heat shrink on coax (i.e. RG-58) because the
center conductor insulator could melt. I assumed that the heat generated by
soldering would at least equal if not exceed that of a heat gun.
Is soldering RG-400 really a kosher thing to do? I assume so, since you
wouldn't have mentioned it, but I just want to confirm.
Thanks,
)_( Dan
RV-7 N714D
http://www.rvproject.com
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: trick for combing out shield?
>
> >
> >In a message dated 2/2/2004 10:22:24 PM Eastern Standard Time,
> >dan(at)rvproject.com writes:
> >Is there any slick trick for combing out braided shielding more easily?
> >Case in point, RG-400 with its double layer of shielding.
>
> Why comb it out? If you want to make connections to
> double shields like RG-400 coax, it's probably better
> to trim the shields just as if you were going to install
> a crimp on connector. Then wrap the exposed shield with
> a piece of braid and solder it. This is a modification
> of the technique shown in:
>
> http://www.aeroelectric.com/articles/pigtail/pigtail.html
>
> For wires with single shields, try the technique shown here:
>
> http://www.aeroelectric.com/articles/shldwire/shldwire.html
>
> This might even work with double shielded wire like RG-400,
> I've not tried it.
>
> In any case, I think you'll be more pleased with the outcome
> if you don't un-braid the strands. Doing that tends to produce
> a finished termination that looks like it's having a bad
> hair day.
>
> Bob
>
>
________________________________________________________________________________
From: | "Cy Galley" <cgalley(at)qcbc.org> |
Subject: | Re: trick for combing out shield? |
I tried soldering the shielding pigtail on a Cessna and it shorted out the
pulses to ground even though my meter said it wasn't grounded. Became
impossible to start.
Cy Galley, TC - Chair, Emergency Aircraft Repair, Oshkosh
Editor, EAA Safety Programs
cgalley(at)qcbc.org or experimenter(at)eaa.org
Always looking for articles for the Experimenter soon to be Sport Pilot
----- Original Message -----
From: "Dan Checkoway" <dan(at)rvproject.com>
Subject: Re: AeroElectric-List: trick for combing out shield?
>
> Bob,
>
> I would have much preferred to do that. That's what I usually do on
> non-coax shielded wire. But a while back I read somewhere (this list, I
> believe) that you shouldn't use heat shrink on coax (i.e. RG-58) because
the
> center conductor insulator could melt. I assumed that the heat generated
by
> soldering would at least equal if not exceed that of a heat gun.
>
> Is soldering RG-400 really a kosher thing to do? I assume so, since you
> wouldn't have mentioned it, but I just want to confirm.
>
> Thanks,
> )_( Dan
> RV-7 N714D
> http://www.rvproject.com
>
> ----- Original Message -----
> From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
> To:
> Subject: Re: AeroElectric-List: trick for combing out shield?
>
>
>
> >
> > >
> > >In a message dated 2/2/2004 10:22:24 PM Eastern Standard Time,
> > >dan(at)rvproject.com writes:
> > >Is there any slick trick for combing out braided shielding more easily?
> > >Case in point, RG-400 with its double layer of shielding.
> >
> > Why comb it out? If you want to make connections to
> > double shields like RG-400 coax, it's probably better
> > to trim the shields just as if you were going to install
> > a crimp on connector. Then wrap the exposed shield with
> > a piece of braid and solder it. This is a modification
> > of the technique shown in:
> >
> > http://www.aeroelectric.com/articles/pigtail/pigtail.html
> >
> > For wires with single shields, try the technique shown here:
> >
> > http://www.aeroelectric.com/articles/shldwire/shldwire.html
> >
> > This might even work with double shielded wire like RG-400,
> > I've not tried it.
> >
> > In any case, I think you'll be more pleased with the outcome
> > if you don't un-braid the strands. Doing that tends to produce
> > a finished termination that looks like it's having a bad
> > hair day.
> >
> > Bob
> >
> >
>
>
________________________________________________________________________________
From: | Joel Harding <cajole76(at)ispwest.com> |
I'm looking for a recommendation for a high quality mini switch ( one
fourth inch throat size) to select between the shunt in my alternator
line and one in the battery lead, before it enters the volt amp meter.
Joel Harding GRT EFIS on the way
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: trick for combing out shield? |
>
>Bob,
>
>I would have much preferred to do that. That's what I usually do on
>non-coax shielded wire. But a while back I read somewhere (this list, I
>believe) that you shouldn't use heat shrink on coax (i.e. RG-58) because the
>center conductor insulator could melt. I assumed that the heat generated by
>soldering would at least equal if not exceed that of a heat gun.
>
>Is soldering RG-400 really a kosher thing to do? I assume so, since you
>wouldn't have mentioned it, but I just want to confirm.
Sure . . . we don't want to solder to RG-58 because it's made
of peanut-butter and bubble-gum . . . typical of materials
around in 1945 when that stuff was designed.
RG-400 is quite solder friendly. I used heat-gun installed
solder sleeves on it all the time.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> regulated alternators |
Subject: | Re: RE: OV protection for internally |
regulated alternators
regulated alternators
>
>
>Bob,
>
> If I have a progressive battery/alternator switch can I still get into
>trouble if I quickly slam it totally off instead of taking the alternator
>off line, pause then turn off the battery? I can see how this might happen
>during an incident, if, for instance, one smelled smoke in the cockpit. Is
>this one senerio of concern?
No, do this with the engine off. Where folks are getting
into trouble is with unnecessary operation of the alternator
switch while the engine is running. There are lots of
controls on an airplane that are operated during narrowly
restricted stages of flight. You don't lower flaps at 175 kts,
You don't pull the mixture to cutoff at cruise, you don't
select OFF on the fuel selector while in flight, etc. etc.
In all my years of flying, I've never had a situation where
I've felt a need to turn either a battery or alternator switch
off after the engine is running except to shut the airplane down
at the end of a flight.
The problem with alternator vulnerability manifests itself
only because folks operated switches in a manner inconsistent
with a trouble free flight. If someone writes to say, "I
lowered my flaps a cruise and they broke off the airplane",
nobody would be surprised at the result, only wonderment at why
anyone believed it was a useful thing to do. Same thing
with a potentially vulnerable, self-regulated alternator.
If you do smell smoke in the cockpit, then concern for the
alternator's regulator is a secondary issue. That's why
absolute control over the alternator's connection to the
system is offered with the Z-24 configuration.
Operate the system just like you've operated in C-172 for
the last 40+ years and vulnerability to battery-dump
damage is never going to be a problem.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: My Jabiru J400 made test flights, |
>
>
>Last Sunday the my Jabiru J400 did its first test flight and a subsequent
>flight of a few hours, all was good, and all the smoke stayed in the wires.
>Elevated CHT due to the new engine, all the rest good and nearly 2000Fpm
>climb, man this is a rocket.
Chalk up another one for the OBAM aircraft industry . . .
the only segment of GA that is growing both in numbers
and technological stature.
Hat's off to brother Ian!
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>Hello Bob,
>
>Thanks for your prompt reply. To first answer your question. Yes, I was
>going to use it on our Model 5 Safari Kitfox that is about 70% complete. I
>too think that it is Kapton wire, but I am not sure. I do not have a spec.
>sheet on it either.
>
>I am nearly four years retired from Sikorsky Aircraft and I suspect that is
>where I obtained the wire. I did a quick check on the internet against this
>wire and the only thing that comes up is a chafing issue on a Sikorsky
>Blackhawk. I have about 1400 feet of 20awg.
If it's Kapton, I don't think I'd use it in your airplane.
I was advised AGAINST Kapton 20 years ago when I was working
the Gates-Piaggio project at Lear . . . seems the Navy was
already having heartburn with that stuff on carrier based
airplanes. Why it has persisted for all these years in
commercial ships is beyond my understanding.
I will invite you to join us on the AeroElectric List
to continue this and similar discussions. It's useful to
share the information with as many folks as possible.
A further benefit can be realized with membership on
the list. There are lots of technically capable folks
on the list who can offer suggestions too. You can
join at . . .
http://www.matronics.com/subscribe/
Thanks!
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
From: | Clay R <clayr_55(at)yahoo.com> |
Subject: | Re: RE: OV protection for internally regulated alternators |
How many people out there were taught in the C-172
that you could switch the alternator off and back on
to test it during the runup? (watch the Ammeter jump
back and forth)
I was.
I guess the question is "how long does it take" to
burn up the internal regulator if the B-lead is
disconnected? A second? 10 seconds?
If accidently flipping a switch on my airplane is
going to cause a component to instantly break, I'm
going to put a big guard on it or change the design.
--Clay
(really sorry to keep flogging this horse)
--- "Robert L. Nuckolls, III" ,
UNEXPECTED_DATA_AFTER_ADDRESS@.SYNTAX-ERROR. wrote:
> Nuckolls, III" regulated
> alternators
>
>
> In all my years of flying, I've never had a
> situation where
> I've felt a need to turn either a battery or
> alternator switch
> off after the engine is running except to shut
> the airplane down
> at the end of a flight.
(snip)
> > Operate the system just like you've operated
in
> C-172 for
> the last 40+ years and vulnerability to
> battery-dump
> damage is never going to be a problem.
>
> Bob . . .
__________________________________
________________________________________________________________________________
From: | "Francis, David CMDR" <David.Francis(at)defence.gov.au> |
Subject: | SEC: UNCLASSIFIED - LIGHTED TOGGLE SWITCHES |
Folks,
Knowing that B&C stock Carling switches, I asked if they would consider
stocking some of the LT series lighted toggle switches. Below is the reply
from B&C.
Regards, David Francis, VH-ZEE, Canberra, Australia
David,
I can get the LT series switches on a special order. Now as far as stocking
them, that will take me a few months, I have got other items that I am
working on at this time, but I will keep the LT switches in consideration.
Thanks,
Todd Koerner
B&C Specialty Products
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: OV protection for internally regulated alternators |
>
>How many people out there were taught in the C-172
>that you could switch the alternator off and back on
>to test it during the runup? (watch the Ammeter jump
>back and forth)
>
>I was.
Why would you do this in an OBAM machine? If you
have ACTIVE notification of low voltage (i.e. low
voltage warning light) and the light goes out
when the engine starts, what's all this
flippy-flippy stuff about?
Someone may have taught you to do that but if the
ammeter was indicating anywhere to the right of
zero, there was nothing more to be learned by
operating the alternator switch. If you closed
the master switch and the panel lights up, then
that too is pretty good evidence that the battery
contactor is working.
I helped craft the 1960's versions of POH
instructions for the SE Cessnas . . . don't know
what they've put in there since I left but I'd be
really surprised if this activity was a factory
recommended pre-flight procedure.
>I guess the question is "how long does it take" to
>burn up the internal regulator if the B-lead is
>disconnected? A second? 10 seconds?
10 MILLISECONDS . . .
>If accidently flipping a switch on my airplane is
>going to cause a component to instantly break, I'm
>going to put a big guard on it or change the design.
You've already changed the design by NOT owning
a C-172. Your not prohibited from doing a lot
of things differently that what you were taught
by folks who understand less about your airplane
than you do.
If there's any possibility of operating a
switch by accident, perhaps there's something
that can be done with ergonomics of layout
to eliminate it.
If you have layouts similar to
http://www.aeroelectric.com/temp/Switches.pdf
Which switch would you be reaching for when
you accidently got the DC PWR MASTER instead?
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: shunt switch |
>
>
>I'm looking for a recommendation for a high quality mini switch ( one
>fourth inch throat size) to select between the shunt in my alternator
>line and one in the battery lead, before it enters the volt amp meter.
Are you running cranking currents through the battery shunt?
My personal choice of switches for ammeter shunts would be the
C&K 7201SYZQE from Digikey and others. See:
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?Ref=212792&Row=201354&Site=US
Bob . . .
________________________________________________________________________________
From: | "Scott Hersha" <shersha(at)fuse.net> |
Subject: | Re: shunt switch |
Bob,
I don't if there is an ammeter shunt on my bus system or not, but there
isn't any cranking amps going through the bus system..I have the EXP bus
system. Maybe there is a ground problem with it. I tried a ferrite bead on
my antenna leads today and they didn't help.
Scott Hersha
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: shunt switch
>
> >
> >
> >I'm looking for a recommendation for a high quality mini switch ( one
> >fourth inch throat size) to select between the shunt in my alternator
> >line and one in the battery lead, before it enters the volt amp meter.
>
> Are you running cranking currents through the battery shunt?
>
> My personal choice of switches for ammeter shunts would be the
> C&K 7201SYZQE from Digikey and others. See:
>
>
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?Ref=212792&Row=2013
54&Site=US
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Scott Hersha" <shersha(at)fuse.net> |
I'm reading chapter 16 in the 'Connection' and will hopefullly find a problem to
fix. I'm also on the list now. The ferrite torroid did not help. Still looking.
Scott Hersha
________________________________________________________________________________
From: | Charlie Kuss <chaskuss(at)bellsouth.net> |
Subject: | Re: Quick connects |
These look interesting. What sort of crimping tool is needed for these? Is it a
proprietary tool? Or is the tool based on an existing standard?
Charlie Kuss
>
>I bought a the Hirose mini circular connector from Digikey. They are very
>small, easy to attach, locking, not real expensive, and sealed. I haven't
>installed it yet but it looks perfect for the elevator trim to 5 wire Ray Allen
>cable.
>
>There is a photo at the following site.
>
>http://www.hirose.com/
>
>wires. This is for an electric trim tab servo and I would like to easily
>remove for repair.>
________________________________________________________________________________
From: | Charlie Kuss <chaskuss(at)bellsouth.net> |
Subject: | Re: Lighted Toggle Switches |
Dave,
Give me more details on this. Are these panels some sort of fiber optic plastic,
with a coating? It appears that the coating is removed by engraving. Do I assume
correctly, that the text areas will emit light? This would be VERY nice.
Charlie Kuss
>
>Another option if you guys are looking for the ultimate in "cool" is to
>forget about lighted switches and go for a backlit switch panel,
>professionally manufactured from your drawings by a company that does
>flight simulator cockpits. Check out the stuff you can get at
>www.AircraftSimulators.com
>
>I just had 2 switch panels made up that you can see at
>http://www.myglasscockpit.com/SwitchPanelLeft.jpg
>and
>http://www.myglasscockpit.com/SwitchPanelCenter.jpg
>
>They can either supply the switches or supply the bare acrylic panel and
>you provide your own switches.
>
>Dave Morris
>
>
>
>>
>>
>>Charlie,
>>
>>These look totally cool. I have not given this a lot of
>>thought, but how would you used the colors in your airplane?
>>I can see a lot of possibilities that could reduce workload
>>and increase safety.
>>
>>Thanks,
>>Mickey
>>
>>
>> >http://www.carlingtech.com/pdf/s_lt.pdf
>> >
>> >Carling is the manufacturer of the switches sold by B&C Specialties. The
>> LT series comes available with 5 different lighting colors and comes in a
>> wide variety of switch styles. They have switches rated up to 15 amps as
>> well. They are also available with 1/4" fast on terminals (as recommended by
--
>>
>>Mickey Coggins
>>http://www.rv8.ch/
>>#82007 Wings
>>
>>
>
>Dave Morris
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>I'm reading chapter 16 in the 'Connection' and will hopefullly find a
>problem to fix. I'm also on the list now. The ferrite torroid did not
>help. Still looking.
>Scott Hersha
What experiments have you conducted to deduce propagation
mode for the noise?
Bob . . .
________________________________________________________________________________
From: | Michel Therrien <mtherr(at)yahoo.com> |
Subject: | Re: RE: OV protection for internally regulated alternators |
That battery dump damage thing... is this only related
with the alternators from Vans, or any automotive
alternators (including the Nippodensos found in
japanese cars)?
Is this a certainty that it will fail each time, or is
it once in a lifetime that this will happen?
Thanks!
Michel
--- "Robert L. Nuckolls, III" ,
> No, do this with the engine off. Where folks
> are getting
> into trouble is with unnecessary operation of
> the alternator
> switch while the engine is running. There are
> lots of....
=====
----------------------------
Michel Therrien CH601-HD, C-GZGQ
http://mthobby.pcperfect.com/ch601
http://www.zenithair.com/bldrlist/profiles/mthobby
http://pages.infinit.net/mthobby
__________________________________
________________________________________________________________________________
From: | Hi There <rv90619(at)yahoo.com> |
Subject: | Converting a Denso Alternator |
I have a couple of Denso Alternators that I want to convert to nonregulated alternators.
I've seen a few different sites that discribe how to do this, but not
one that has the same type of regulator that are on my alternators. Both alternators
I have have a plastic regulator/plug housing. There are cooling The
regulator bolts to the diodes and brushes. I'm sure someone has done one of
these alternators, I was at the junk yard today and many of the import cars
used an alternator of this disign. I have some photos if that helps.
Thanks for any help.
Cameron
---------------------------------
________________________________________________________________________________
From: | "Richard E. Tasker" <retasker(at)optonline.net> |
Subject: | Re: Quick connects |
Do you have a digikey part number for this? I tried looking on Digikey
and couldn't find the one like the picture.
Dick Tasker, RV9A #90573
N67BT(at)aol.com wrote:
>
>I bought a the Hirose mini circular connector from Digikey. They are very
>small, easy to attach, locking, not real expensive, and sealed. I haven't
>installed it yet but it looks perfect for the elevator trim to 5 wire Ray Allen
>cable.
>
>There is a photo at the following site.
>
>http://www.hirose.com/
>
>wires. This is for an electric trim tab servo and I would like to easily
>remove for repair.>
>
>
>
>
________________________________________________________________________________
From: | "Scott Hersha" <shersha(at)fuse.net> |
I haven't tried any experiments yet except using a ferrite toroid on the
antenna lead. No help. After reading chapter 16, I think I potentially have
several areas for concern. My wires are probably not bundled properly to
keep certain wires separated. My strobe power lead shield is grounded at the
power supply only not the strobe lamp also. I'm going to build 3
capacitor/filters you describe, one for the intercom power, and one each for
the two strobe power supplys. I'm also going to try connecting my com radio
to a 'clean' power source..separate battery. I'll disconnect the radio
antenna first to see if the noise is coming through it or the bus. All these
'experiments' will take some time, but if none of these work, I'll get back
to you....Thanks, Scott Hersha
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: Noise
>
> >
> >I'm reading chapter 16 in the 'Connection' and will hopefullly find a
> >problem to fix. I'm also on the list now. The ferrite torroid did not
> >help. Still looking.
> >Scott Hersha
>
> What experiments have you conducted to deduce propagation
> mode for the noise?
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: OV protection for internally regulated alternators |
>
>That battery dump damage thing... is this only related
>with the alternators from Vans, or any automotive
>alternators (including the Nippodensos found in
>japanese cars)?
>
>Is this a certainty that it will fail each time, or is
>it once in a lifetime that this will happen?
>
>Thanks!
>
>Michel
Z-24 has been published for several years. I have
to believe there have been a lot of systems installed
and are flying. The questions are:
(1) how many alternators are subject to this failure
because their internal regulators are not rated for
the battery-dump stress?
(2) how many builders have put their particular
alternator "to the test" by cycling the alternator
control switch while the alternator was working
hard?
There are so many variables here that a truly
quantitative response to your question cannot be
deduced from what we know.
I'm not sure which alternator Van's is selling.
I THOUGHT it was an ND alternator. Does anyone
know?
It does take a combination of conditions to
trigger the event:
(1) relatively old design for built in regulator
that is NOT protected from the battery-dump
transient.
(2) size of the transient is a function of how
fast alternator is running and at what load
when the connection between b-lead and battery
is broken.
When fitted with rudimentary electrical system
instrumentation (low volts warning light or
a voltmeter) there is no practical need or
routinely exercised practice that calls for
opening the alternator disconnect contactor
while the engine is running IRRESPECTIVE
of alternator vulnerability.
If EVERY airplane I've ever rented over the
past 23 years had been vulnerable to this
failure mode, I'm 99.9% certain that the mode
would not have been triggered while I was
using the airplane . . . i.e. I've never
had a situation arise where it was valuable
or even interesting to operate the switch
with the engine running.
At the moment, my sense is that given the way
MOST of us were taught (or not) on how
to operate the airplane, the risks to even
vulnerable alternators is quite low.
The risk can be driven essentially zero once
the magnitude of the transient is characterized
and prophylactic measures implemented. At this
point in the investigation, it would be a sad
thing for a builder to jerk his perfectly working
alternator off in knee-jerk response to truthful
but poorly quantified warnings from well meaning
folks who don't understand the system.
Bob . . .
________________________________________________________________________________
From: | Mark Steitle <msteitle(at)mail.utexas.edu> |
Subject: | Re: Converting a Denso Alternator |
>
>
>I have a couple of Denso Alternators that I want to convert to
>nonregulated alternators.
Cameron,
I posted this procedure a while back, but couldn't find it in the
archives. So, here is the procedure I used to convert my two ND
alternators to external regulator mode.
Mark
=============================================
Bob N. strongly recommends using externally regulated alternators only, or
modifying the internal regulator models so as to allow it to be shut down
if necessary. (Supposedly, a voltage run-away can happen in a few seconds.)
Problem is that the articles I read explaining how to convert the
internally regulated alternators to external regulation didn't work. (Did I
do something wrong?) I think I have worked out a simpler solution. The
objective here is to isolate the field windings from the diode bridge so
that the alternator can then be externally controlled.
This is how I went about converting my alternators. First I removed the
back cover, exposing the diode bridge, regulator assy. and brush holder.
Then removed the regulator and brush holder and threw the regulator assy in
the trash. Next I removed the brush holder and shaped a little brace from
1/8" phenolic that will support one side of the brush holder and isolate it
from the diode bridge. This piece will be about 7/8" x 1/4" with a #8 hole
in each end. Do not make this piece out of metal or it will short out the
diode bridge. Also make up a jumper wire about three inches long with a
ring terminal on each end. One end will attach to the right terminal on the
brush holder and the other will attach to the alternator case (gnd.).
The other terminal on the brush holder will need a spacer under it to keep
everything aligned properly. The left brush will need to have the lead wire
un-soldered from the brush holder. The wire comes through the back of the
brush holder. Unsolder it there and drill out the hole just a bit to allow
a #20 wire with shrink tube to fit snugly through the hole. Solder the #20
wire to the end of the braided wire on the brush.
Now we're ready to reassemble the whole thing. Pass the #20 wire through
the hole drilled in the brush holder and reinsert the spring and brush.
Screw the brush holder back into place, with a spacer washer under the left
terminal. The ground wire goes on the opposite terminal. Feed the wire
soldered to the brush through a hole in the alternator cover, with a
grommet to prevent chaffing. This wire will go to the "F" terminal of the
external voltage regulator. I used a generic Ford unit from a mid-seventies
model (approx. $10/ea from Auto Zone). The S & A terminals of the regulator
tie together and get fed from the alt. switch & 5 amp breaker. The "B"
terminal on the alternator goes to the battery contactor. The other
terminal on the regulator isn't used.
I modified two ND alternators using this method and they both work great.
It takes about 30 minutes to do the modifications. All I need to do now is
add a crowbar over-voltage protector to each regulator and I'm set to go.
Or you can use a B&C voltage regulator with built-in OVP and low-voltage
warning.
________________________________________________________________________________
From: | Joel Harding <cajole76(at)ispwest.com> |
Subject: | Re: shunt switch |
On Feb 3, 2004, at 4:45 PM, Robert L. Nuckolls, III wrote:
>
>
>>
>>
>>
>> I'm looking for a recommendation for a high quality mini switch ( one
>> fourth inch throat size) to select between the shunt in my alternator
>> line and one in the battery lead, before it enters the volt amp meter.
>
> Are you running cranking currents through the battery shunt?
>
>
No, it's in the lead from the battery to the ess. bus, so it won't be
exposed to cranking currents.
Joel
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>I haven't tried any experiments yet except using a ferrite toroid on the
>antenna lead. No help. After reading chapter 16, I think I potentially have
>several areas for concern. My wires are probably not bundled properly to
>keep certain wires separated.
Possible problem but pretty low on list of probabilities
> My strobe power lead shield is grounded at the
>power supply only not the strobe lamp also.
that's fine. ground shield at power supply end only.
> I'm going to build 3
>capacitor/filters you describe, one for the intercom power, and one each for
>the two strobe power supplys.
Whups . . . don't do this yet.
> I'm also going to try connecting my com radio
>to a 'clean' power source..separate battery.
Good idea.
> I'll disconnect the radio
>antenna first to see if the noise is coming through it or the bus.
another good idea
> All these
>'experiments' will take some time, but if none of these work, I'll get back
>to you.
Do the detective work before you buy any parts.
We await the results of your investigation.
Bob . . .
________________________________________________________________________________
Subject: | Antenna(S) for Com(s)? |
Im adding a second com to my airplane. question is, do I need a second com
antenna if I dont intend to transmit on both coms at the same time?
________________________________________________________________________________
From: | Rick Johnson <ricklj(at)silverstar.com> |
Subject: | start up/shut down procedure |
Bob: I am wiring my RV7 according to your Z-13 and Z-24 diagrams. The
only exception is I am using a 2-3 switch for my battery/alternator field
switch instead of your 2-10. I would like to know what the proper start up
- system check - shut down procedure should be. How should I check to see
if the SD-8 alternator is working correctly after the engine is running?
What will the ammeter on that circuit read if the auxiliary alternator
switch is off? Sounds like after start up, I wouldn't want to switch off
the battery/primary alternator then switch on the e-bus and auxiliary
alternator to see if it is carrying the system load properly. I'm confused
and would rather get some good advice from you before ruining some
expensive equipment. And thanks for your fantastic web site and all the
great advice you dispense here.
rick
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Antenna(S) for Com(s)? |
>
>Im adding a second com to my airplane. question is, do I need a second com
>antenna if I dont intend to transmit on both coms at the same time?
Yes, you'll want to listen on both and while this could be done
with a splitter, you can't used the splitter to transmit. If you
use a relay or switch to put one antenna on the active transmitter,
then you can't hear on both receivers.
Further, putting such gizmos in the antenna for both transceivers
gives you a single point of failure for both radios. You loose
both utility and reliability when you try to share the antenna
between two transceivers.
Bob . . .
________________________________________________________________________________
From: | "Wayne Berg" <wfberg(at)msn.com> |
Subject: | Re: Antenna(S) for Com(s)? |
Yes. You would need a coax switch in the line to isolate your transmitters. Without
that or a second antenna you would be sending RF back into the second Com.
Very bad and very expensive. Keep second com antenna at least 21" from the other
com antenna.
----- Original Message -----
From: N27160(at)aol.com
Subject: AeroElectric-List: Antenna(S) for Com(s)?
Im adding a second com to my airplane. question is, do I need a second com
antenna if I dont intend to transmit on both coms at the same time?
________________________________________________________________________________
From: | Clay R <clayr_55(at)yahoo.com> |
Subject: | Re: OV protection for internally regulated alternators |
I'm going to reluctantly reply to your message and it
will be my very last post to this list on the subject.
I personally feel like I am being blamed for "not
knowing" that I shouldn't have switched off the
alternator switch while the engine was running.
Sorry if I was taught it could be done on a Cessna...
old habits die hard and turning off the alternator
with the engine running shouldn't be OK on one plane
but not another unless labeled as such. All I
originally wanted was a warning on Z-24 to keep others
from making the same mistake I did.
--- "Robert L. Nuckolls, III"
wrote:
> Nuckolls, III"
>
>
> Z-24 has been published for several years. I have
> to believe there have been a lot of systems
> installed
> and are flying. The questions are:
>
Z-24 may have been published for several years... but
that DOES NOT mean there are a lot of people flying it
yet and there isn't a problem with it.
The time required to build an airplane means that an
idea needs to be out there for a year or two before it
will be flying. When it was published, builders would
need to be BEFORE the wiring stage to implement this
idea easily... those that had already planned and
started their wiring when z-24 was published probably
didn't implement it because the idea was new and would
require rework.
I personally have never encountered another z-24
airplane flying, and neither had the DAR who certifies
experimental planes every week in the Dallas area.
Please, speak up if you have your flying plane wired
like z-24 and have (or have not) seen any issues with
it. Any additional data points will help.
> (1) how many alternators are subject to this
> failure
> because their internal regulators are not rated
> for
> the battery-dump stress?
>
> (2) how many builders have put their particular
> alternator "to the test" by cycling the
> alternator
> control switch while the alternator was working
> hard?
>
I had my EFIS/One turned on (3.5A), the Lightspeed
(1.3A), and the engine was at a slow idle. My battery
was charged, and there were no radios on, no lights,
nothing else... Does this qualify as working hard?
> There are so many variables here that a truly
> quantitative response to your question cannot be
> deduced from what we know.
>
> I'm not sure which alternator Van's is selling.
> I THOUGHT it was an ND alternator. Does anyone
> know?
My alternator from Vans has ND stamped on it.
>
> It does take a combination of conditions to
> trigger the event:
>
> (1) relatively old design for built in regulator
> that is NOT protected from the battery-dump
> transient.
>
> (2) size of the transient is a function of how
> fast alternator is running and at what load
> when the connection between b-lead and battery
> is broken.
>
> When fitted with rudimentary electrical system
> instrumentation (low volts warning light or
> a voltmeter) there is no practical need or
> routinely exercised practice that calls for
> opening the alternator disconnect contactor
> while the engine is running IRRESPECTIVE
> of alternator vulnerability.
>
> If EVERY airplane I've ever rented over the
> past 23 years had been vulnerable to this
> failure mode, I'm 99.9% certain that the mode
> would not have been triggered while I was
> using the airplane . . . i.e. I've never
> had a situation arise where it was valuable
> or even interesting to operate the switch
> with the engine running.
Rental airplanes and OBAM with z-24 are different...
Rentals have externally regulated alternators without
a contactor on the B-lead.
>
> At the moment, my sense is that given the way
> MOST of us were taught (or not) on how
> to operate the airplane, the risks to even
> vulnerable alternators is quite low.
>
> The risk can be driven essentially zero once
> the magnitude of the transient is characterized
> and prophylactic measures implemented. At this
> point in the investigation, it would be a sad
> thing for a builder to jerk his perfectly working
> alternator off in knee-jerk response to truthful
> but poorly quantified warnings from well meaning
> folks who don't understand the system.
>
> Bob . . .
If I'm the one giving the truthful but poorly
quantified warning, and don't understand the system,
I'm sorry for being well-meaning and bringing it up.
In retrospect, It would have been less stressful to
quietly switch to an externally regulated alternator
and left it for someone else to bring up. From the
amount of email I've received, people seem to be happy
I've shared my experience with the group.
I do believe that once the problem is fully tested and
understood a fix will be found for z-24 (or no problem
will be found at all.. it was user error), and
everyone will be happy once again. We live and learn
and move on.
For now Bob's right, don't change your alternator,
just don't switch it off unless you want to help with
the testing. ;-)
-Clay
__________________________________
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Internally regulated alternators |
>Here is a single point anecdotal observation.
>
>There is only one "Vans" 60 Amp alternator on our airfield, and it is a
>rebuilt Mitsubishi. It looks like a later generation alternator ( Vented
>frame, and internal fans); however it is of the ilk which, once activated
>with the alt switch, it will not turn off with the alt switch. He has had
>no serious problems with it. This one was purchased several years ago and
>no telling what Van is selling now.
This is consistent with other notes I'm getting. Van's
has sold several different models over the years. None
are new, most if not all are re-builds of some kind.
Here's where it gets sticky. These modern alternators
are mechanically and electrically quite robust. I'd
guess that the most common reason for an alternator to
be replaced is from brush wear, bearing wear or
regulator failure.
For every OEM that builds alternators as products they'll
be proud of, there are dozens of after-market manufacturers
of replacement regulators. I've often opined that ND
alternators are among the best bets out there for
a reliable alternator . . . this is reinforced with
first hand knowledge of B&C's success with this product.
B&C chooses not to put original equipment regulators
to the test opting instead of offering their own flavor
of external regulator.
Once the alternator is opened for rebuilding,
there is risk that the final product will become
something less than the original manufacturer would
be willing to put their brand on. The biggest single
variable will be design of a replacement regulator.
"Load dump" in cars is a very rare event . . . if
a regulator manufacturer can make a few pennies more
per unit by short changing load dump immunity . . .
well, we know which way that decision often goes.
>Most of the other Van's planes on our air field have Denso 40 A alternators
>which came from Niagra Air Parts, and are new, fairly late models. These
>look just like the B&C, but have internal regulators. I have personally
>checked several times and it does shut down with the switch
>(Sensor/regulator power?). I have it wired with the contactor and OVM. I
>have also opened the Alt main (B lead) CB several times when under load and
>it doesn't seem to harm it. I ain't doing that any more; however. I start
>with it off and turn it on when the motor is running. It comes off after
>engine shut down.
A very rational approach to risk reduction . . . and it
may be that you're seeing mostly new machines with ND original
regulators that are not vulnerable to battery-dump
events.
>It is therefore my belief that the very popular 40 Amp Denso bought new from
>Niagra has a regulator which has dump logic in it. It seems bullet proof in
>that regard; however I still feel the need for the OV module and contactor,
>in case of the internal failure mode which you describe.
>
>This is not much of a data point but it sounds like you are starting from
>scratch, so I hope this helps.
Very helpful, thanks!
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
Subject: | Connector for elevator trim servo |
Photos and info on the Hirose connector I plan to use for the elevator trim
servo are posted on my web site.
http://users.aol.com/n67bt
This thing looks like just the ticket. What do you think Bob N.?
They cost around $14 for the pair.
Bob Trumpfheller
RV7A
Western Colorado
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: start up/shut down procedure |
>
>Bob: I am wiring my RV7 according to your Z-13 and Z-24 diagrams. The
>only exception is I am using a 2-3 switch for my battery/alternator field
>switch instead of your 2-10. I would like to know what the proper start up
>- system check - shut down procedure should be. How should I check to see
>if the SD-8 alternator is working correctly after the engine is running?
>What will the ammeter on that circuit read if the auxiliary alternator
>switch is off? Sounds like after start up, I wouldn't want to switch off
>the battery/primary alternator then switch on the e-bus and auxiliary
>alternator to see if it is carrying the system load properly. I'm confused
>and would rather get some good advice from you before ruining some
>expensive equipment. And thanks for your fantastic web site and all the
>great advice you dispense here.
I'll suggest that you replace the 2-3 with a 2-10. Start with
battery only. After engine starts, test the SD-8 before you
turn the main alternator on.
An option: Make the aux alternator switch a 2-3 where control
current for main alternator goes through the second set of
contacts such that the main alternator is disabled any time
the SD-8 is ON. Start with the both DC PWR MASTER and AUX ALT
switches ON. After preflight of the SD-8 is complete, turn
it OFF and it will be replaced by the main alternator.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Ned Thomas" <315(at)cox.net> |
Subject: | Re: start up/shut down procedure |
Don't know if this is pertainant to this thread but I understand that once
the SD-8 is energized it remains energized producing power until it stops
rotating.
It hasn't been made clear to me whether this is detrimental to have it
running energized while disconnected from everything??
________________________________________________________________________________
From: | "Steve Sampson" <SSampson.SLN21(at)london.edu> |
Subject: | Re: OV protection for internally regulated alternators |
/ ND alternator
Michael/Bob, The alternator VANS shipped to me IS a refurb Nippon Denso
(Spelling?) alternator. It is the one on p7 of the 2003 accesory catalogue.
I had suggested the 35Amp externally regulated one but they suggested this
was a better bet and lighter.
Steve.
-----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
Subject: AeroElectric-List: Re: OV protection for internally regulated
alternators
>
>That battery dump damage thing... is this only related
>with the alternators from Vans, or any automotive
>alternators (including the Nippodensos found in
>japanese cars)?
>
>Is this a certainty that it will fail each time, or is
>it once in a lifetime that this will happen?
>
>Thanks!
>
>Michel
Z-24 has been published for several years. I have
to believe there have been a lot of systems installed
and are flying. The questions are:
(1) how many alternators are subject to this failure
because their internal regulators are not rated for
the battery-dump stress?
(2) how many builders have put their particular
alternator "to the test" by cycling the alternator
control switch while the alternator was working
hard?
There are so many variables here that a truly
quantitative response to your question cannot be
deduced from what we know.
I'm not sure which alternator Van's is selling.
I THOUGHT it was an ND alternator. Does anyone
know?
It does take a combination of conditions to
trigger the event:
(1) relatively old design for built in regulator
that is NOT protected from the battery-dump
transient.
(2) size of the transient is a function of how
fast alternator is running and at what load
when the connection between b-lead and battery
is broken.
When fitted with rudimentary electrical system
instrumentation (low volts warning light or
a voltmeter) there is no practical need or
routinely exercised practice that calls for
opening the alternator disconnect contactor
while the engine is running IRRESPECTIVE
of alternator vulnerability.
If EVERY airplane I've ever rented over the
past 23 years had been vulnerable to this
failure mode, I'm 99.9% certain that the mode
would not have been triggered while I was
using the airplane . . . i.e. I've never
had a situation arise where it was valuable
or even interesting to operate the switch
with the engine running.
At the moment, my sense is that given the way
MOST of us were taught (or not) on how
to operate the airplane, the risks to even
vulnerable alternators is quite low.
The risk can be driven essentially zero once
the magnitude of the transient is characterized
and prophylactic measures implemented. At this
point in the investigation, it would be a sad
thing for a builder to jerk his perfectly working
alternator off in knee-jerk response to truthful
but poorly quantified warnings from well meaning
folks who don't understand the system.
Bob . . .
---
Incoming mail is certified Virus Free.
---
________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
Subject: | Re: Antenna(S) for Com(s)? |
You could build up a relay that your PTT connector plugs into, that would
disconnect the 2nd comm radio from the antenna when you push the mike
button. A lot has been written about that sort of thing in the amateur
radio circles. If you're handy with a soldering iron, do a Google.com
search for QSK TR SWITCH and see what's been written.
Dave Morris
N5UP
>
>
> >
> >Im adding a second com to my airplane. question is, do I need a second com
> >antenna if I dont intend to transmit on both coms at the same time?
>
> Yes, you'll want to listen on both and while this could be done
> with a splitter, you can't used the splitter to transmit. If you
> use a relay or switch to put one antenna on the active transmitter,
> then you can't hear on both receivers.
>
> Further, putting such gizmos in the antenna for both transceivers
> gives you a single point of failure for both radios. You loose
> both utility and reliability when you try to share the antenna
> between two transceivers.
>
> Bob . . .
>
>
Dave Morris
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | OV protection for internally regulated alternators |
>
>I'm going to reluctantly reply to your message and it
>will be my very last post to this list on the subject.
>
>I personally feel like I am being blamed for "not
>knowing" that I shouldn't have switched off the
>alternator switch while the engine was running.
Not at all my friend. There was nothing inherently
wrong with turning the alternator on/off at ANY
time . . . under the best of circumstances it
shouldn't be a problem with ANY alternator on
ANY airplane whether certified or OBAM.
>Sorry if I was taught it could be done on a Cessna...
>old habits die hard and turning off the alternator
>with the engine running shouldn't be OK on one plane
>but not another unless labeled as such. All I
>originally wanted was a warning on Z-24 to keep others
>from making the same mistake I did.
Exactly. My comments were directed not at
you for doing what you were taught but more
toward your teachers who were augmenting the
POH by suggesting a pre-flight activity that
added no value . . . which serendipitously
exposed a vulnerability of an alternator
in an OBAM aircraft.
This happens all the time in both the certified
and OBAM world. Some day when I don't have to
worry about ticking off the folks who sign my
paychecks, I'll be able to relate some pretty
hair-raising anecdotes in the heavily regulated
and conformed world of certified aircraft.
If my tone was skeptical/sarcastic/incredulous
please know it had nothing to do with you
personally. We're all products of our experiences.
I'm singularly fortunate to have a rich history
of experiences.
My job is not to convince you of anything but to
share what I've learned and try to explain how
the simple-ideas piece together to make a system
work/not-work. You're encouraged to use any part of
this effort in which you find value. If you find
something I've offered unconvincing, it's either
because I'm in error or I've failed in my role as
teacher.
I am pleased that you DID reply and make me aware
of your perceptions. It probably happens to others
who feel like they're being chased off. I encourage
you and others who participate on this list to
remember that when the wild-eyed, gray beard in
the Spam Can Capitol gets all excited, it's about
the physics and logic of the matter, not the folks . . .
and in particular folks who are helping me help others
by sharing their own experiences.
Please don't let this experience become inhibiting.
There's a lot of sand and dust to sift to search out
the simple-ideas. I value and appreciate your
participation more than you know. When the dust
finally settles on any discussion, it's my most
sincere wish that we will have sorted out the best
ideas worthy of passing on to others.
Bob . . .
________________________________________________________________________________
From: | "Steve Sampson" <SSampson.SLN21(at)london.edu> |
Subject: | Re: OV protection for internally regulated alternators |
Clay - thanks VERY much for raising this issue. It has been very helpful to
me. Dont feel bad. Steve.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Clay R
Subject: Re: AeroElectric-List: Re: OV protection for internally
regulated alternators
I'm going to reluctantly reply to your message and it
will be my very last post to this list on the subject.
I personally feel like I am being blamed for "not
knowing" that I shouldn't have switched off the
alternator switch while the engine was running.
Sorry if I was taught it could be done on a Cessna...
old habits die hard and turning off the alternator
with the engine running shouldn't be OK on one plane
but not another unless labeled as such. All I
originally wanted was a warning on Z-24 to keep others
from making the same mistake I did.
--- "Robert L. Nuckolls, III"
wrote:
> Nuckolls, III"
>
>
> Z-24 has been published for several years. I have
> to believe there have been a lot of systems
> installed
> and are flying. The questions are:
>
Z-24 may have been published for several years... but
that DOES NOT mean there are a lot of people flying it
yet and there isn't a problem with it.
The time required to build an airplane means that an
idea needs to be out there for a year or two before it
will be flying. When it was published, builders would
need to be BEFORE the wiring stage to implement this
idea easily... those that had already planned and
started their wiring when z-24 was published probably
didn't implement it because the idea was new and would
require rework.
I personally have never encountered another z-24
airplane flying, and neither had the DAR who certifies
experimental planes every week in the Dallas area.
Please, speak up if you have your flying plane wired
like z-24 and have (or have not) seen any issues with
it. Any additional data points will help.
> (1) how many alternators are subject to this
> failure
> because their internal regulators are not rated
> for
> the battery-dump stress?
>
> (2) how many builders have put their particular
> alternator "to the test" by cycling the
> alternator
> control switch while the alternator was working
> hard?
>
I had my EFIS/One turned on (3.5A), the Lightspeed
(1.3A), and the engine was at a slow idle. My battery
was charged, and there were no radios on, no lights,
nothing else... Does this qualify as working hard?
> There are so many variables here that a truly
> quantitative response to your question cannot be
> deduced from what we know.
>
> I'm not sure which alternator Van's is selling.
> I THOUGHT it was an ND alternator. Does anyone
> know?
My alternator from Vans has ND stamped on it.
>
> It does take a combination of conditions to
> trigger the event:
>
> (1) relatively old design for built in regulator
> that is NOT protected from the battery-dump
> transient.
>
> (2) size of the transient is a function of how
> fast alternator is running and at what load
> when the connection between b-lead and battery
> is broken.
>
> When fitted with rudimentary electrical system
> instrumentation (low volts warning light or
> a voltmeter) there is no practical need or
> routinely exercised practice that calls for
> opening the alternator disconnect contactor
> while the engine is running IRRESPECTIVE
> of alternator vulnerability.
>
> If EVERY airplane I've ever rented over the
> past 23 years had been vulnerable to this
> failure mode, I'm 99.9% certain that the mode
> would not have been triggered while I was
> using the airplane . . . i.e. I've never
> had a situation arise where it was valuable
> or even interesting to operate the switch
> with the engine running.
Rental airplanes and OBAM with z-24 are different...
Rentals have externally regulated alternators without
a contactor on the B-lead.
>
> At the moment, my sense is that given the way
> MOST of us were taught (or not) on how
> to operate the airplane, the risks to even
> vulnerable alternators is quite low.
>
> The risk can be driven essentially zero once
> the magnitude of the transient is characterized
> and prophylactic measures implemented. At this
> point in the investigation, it would be a sad
> thing for a builder to jerk his perfectly working
> alternator off in knee-jerk response to truthful
> but poorly quantified warnings from well meaning
> folks who don't understand the system.
>
> Bob . . .
If I'm the one giving the truthful but poorly
quantified warning, and don't understand the system,
I'm sorry for being well-meaning and bringing it up.
In retrospect, It would have been less stressful to
quietly switch to an externally regulated alternator
and left it for someone else to bring up. From the
amount of email I've received, people seem to be happy
I've shared my experience with the group.
I do believe that once the problem is fully tested and
understood a fix will be found for z-24 (or no problem
will be found at all.. it was user error), and
everyone will be happy once again. We live and learn
and move on.
For now Bob's right, don't change your alternator,
just don't switch it off unless you want to help with
the testing. ;-)
-Clay
__________________________________
---
Incoming mail is certified Virus Free.
---
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: start up/shut down procedure |
>
>Don't know if this is pertainant to this thread but I understand that once
>the SD-8 is energized it remains energized producing power until it stops
>rotating.
>
>It hasn't been made clear to me whether this is detrimental to have it
>running energized while disconnected from everything??
No, the SD-8 is a permanent magnet alternator. It's ALWAYS producing
output power whether or not it is turned on or loaded. At this time
I'm unaware of any risk to the alternator system for operating it
in the unloaded mode. There are airplanes flying the All-Electric-Airplane-
on-a-Budget system with hundreds of trouble free hours on them.
I had one builder write a year or more ago to tell me that the
SD-8 in his airplane had been called upon to do its job after
a wire became unhooked in his main alternator system. He said
the system performed as expected.
Bob . . .
________________________________________________________________________________
Subject: | Re: start up/shut down procedure |
From: | "Matt Prather" <mprather(at)spro.net> |
Hi Bob,
You said that the damaging voltage dump conditions happens when the
alternator is under significant load, and is suddenly disconnected
from that load. I gather that the problem is that some of the
regulators don't pull down the field current fast enough to reduce the
output of the alternator. Is that right? Or is that there is
signficant inductive stored energy in the output of the alternator,
and driving the output current to zero by disconnecting the alternator
causese the output voltage to spike?
Either way, would you say that the alternator can safely be
disconnected when its output current is low (0A)? Have to wait until
the battery is charged, and the pitot heat/nav lights are off...
I also wonder how large the disconnect relay needs to be if attempting
to disconnect the alternator from the bus causes such a large
transient. Will the small relays that you sell be up to the task for
an airplane that doesn't have a starter (ie, no large contactor)?
One final question: What effect will the TVS have should the atl/reg
suffer from an over voltage event, not related to turning off the alt
switch while the engine is running? Will the TVS have a turn-on
voltage higher than a typical overvoltage value? I suppose this may
be a moot point, since if the regulator cooks, causing an ov even,
I may not care what happens to the TVS, as long as the crow bar
stuff works.
None of these questions is of earth shattering significance, as it
appears that you fully understand what is going on. However, I am
interested in the topic out of curiousity.
I am interested in seeing any data you take with regard to how long
the battery/load dump even lasts, and how much total engergy is
dissipated in the process.
Regards,
Matt Prather
N34RD
________________________________________________________________________________
From: | Kent Sorensen <kents(at)snak.com> |
I keep seeing the acronym OBAM. It 's obviously referring to amateur
built aircraft as opposed to certified ones. What does it stand for ?
Owner Built Amateur Made or something ?
Kent
________________________________________________________________________________
From: | Dj Merrill <deej(at)thayer.dartmouth.edu> |
Subject: | Re: OV protection for internally regulated |
alternators
Steve Sampson wrote:
>
> Clay - thanks VERY much for raising this issue. It has been very helpful to
> me. Dont feel bad. Steve.
And educational for me. It is good to
question things less we become too complacent... ;-)
Please continue to do so. Unless questioned,
we generally take things our flight instructors teach
us as gospel. Flight instructors are people, too, and
might make mistakes or assumptions about things that
aren't entirely true. This is a great forum for
flushing out those myths about electrical related
items in aircraft. I usually lurk, rather than
post, and I've learned tons! :-)
-Dj
--
Dj Merrill Thayer School of Engineering
ThUG Sr. Unix Systems Administrator 8000 Cummings Hall
deej(at)thayer.dartmouth.edu - N1JOV Dartmouth College, Hanover, NH 03755
"On the side of the software box, in the 'System Requirements' section,
it said 'Requires Windows 95 or better'. So I installed Linux." -Anonymous
________________________________________________________________________________
From: | "Ned Thomas" <315(at)cox.net> |
Subject: | Alternator Recommendation and Conversions |
I thought I would recount my experience with Powermaster for those of you
looking for an alternator. I would also suggest B&C. Powermaster is an
automotive aftermarket firm specializing in racing products. You can buy
them thru Summit and others and sometimes on eBay.
http://store.summitracing.com/partdetail.asp?part=PWM%2D8162
After I experienced the OV on the RV6A, I took the alternator in to the
local O'Reilly's and they put it on the test stand. It immediately produced
25 volts. I called the vendor, powermaster, and explained the situation.
They said send it back and we'll repair it. They repaired it for free and
ran it thru their tests and sent me their results tabulated and graphed.
This alternator is a version of the Denso and was a "one wire" alternator.
Powermaster told me they could configure it so that an additional wire would
be available to turn on / off the alternator. So when I incorporated the
Z-24 suggestions to the rewiring it worked fine. I had no problem with this
alternator wired with the OV protection as suggested by Z-24.
It was a 50 amp model 8162 and was very light at 5.68-lbs. It has what they
call a "heat dispersant coating" that is black.
http://www.powermastermotorsports.com/Racing/Denso_Alternators/denso_alternators.html
More details:
http://www.powermastermotorsports.com/Tech_Help/FAQ_s_-_Racing_Alternators/faq_s_-_racing_alternators.html#race3
For those interested the test data was:
Max output power: 695 Watts
Max output power under full load 53 Amps
Field current 0.01 Amps
Turn on Speed (less than): 2600RPM
Leakage current tested @ 12 volts: 0.75 Amps
Ripple current @ 2500 RPM: 11 Amps
Pulley ratio: 2.05
There is a graph of Amps vs RPM and a Scope pattern at 2500 RPM that looks
like a sine wavefrom +- about 7Amps
I don't know what much of this means but it was nice to have the data......
Although the B&C weighs slightly more at 6.1 lbs it might be a better
option.
http://www.bandcspecialty.com/L40desc.html
http://www.bandcspecialty.com/L40-out.PDF
To convert and internally regulated alternator to and external regulated
alternator I found the following link quite helpful:
http://www.miramarcollege.net/programs/avim/faculty/north/alternator/index.htm
Best Regards,
Ned
________________________________________________________________________________
From: | "Ageless Wings" <harley(at)AgelessWings.com> |
Hi, Kent...
I'll save Bob the effort this time! You are close....it's Owner Built
and Maintained.
Harley
Long EZ N28EZ...
in the hanger, getting sanded and primed!
Harley Dixon
Website: www.AgelessWings.com
Email: harley(at)agelesswings.com
Henrietta, NY
USA
|-----Original Message-----
|From: owner-aeroelectric-list-server(at)matronics.com
|[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Kent
|Sorensen
|Sent: Wednesday, February 04, 2004 4:24 PM
|To: aeroelectric-list(at)matronics.com
|Subject: AeroElectric-List: OBAM ?
|
|
|
|I keep seeing the acronym OBAM. It 's obviously referring to amateur
|built aircraft as opposed to certified ones. What does it stand for ?
|
|Owner Built Amateur Made or something ?
|
|Kent
|
|
|
|
|
|
|
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | OV protection for internally regulated alternators |
>
>
>Michael/Bob, The alternator VANS shipped to me IS a refurb Nippon Denso
>(Spelling?) alternator. It is the one on p7 of the 2003 accesory catalogue.
>I had suggested the 35Amp externally regulated one but they suggested this
>was a better bet and lighter.
>
>Steve.
Thanks Steve. It may be that "refurb" regulators are the
real root cause of the vulnerability.
Bob . . .
________________________________________________________________________________
From: | "Beckman, Rick" <Rick.Beckman(at)atk.com> |
ernators
Subject: | OV protection for internally regulated alt |
ernators
>I personally feel like I am being blamed .......
Please don't let this experience become inhibiting.
There's a lot of sand and dust to sift to search out
the simple-ideas. I value and appreciate your
participation more than you know. When the dust
finally settles on any discussion, it's my most
sincere wish that we will have sorted out the best
ideas worthy of passing on to others.
Bob . . .
Bob,.... Thanks for that excellent reply, further
assuring your public that
no matter what the discussion, it never becomes a personal
grudge match with you
and others involved. I, personally, have gleaned a wealth of
information from all
the Matronics sites to which I subscribe, definitely this
one! Keep on keepin' on!
See
ya Saturday! God Bless!
Rick
________________________________________________________________________________
From: | "Dan Branstrom" <danbranstrom(at)verizon.net> |
Owner Built And Maintained. I asked the same question a while ago. ;
)
Dan Branstrom
----- Original Message -----
From: "Kent Sorensen" <kents(at)snak.com>
Subject: AeroElectric-List: OBAM ?
>
> I keep seeing the acronym OBAM. It 's obviously referring to amateur
> built aircraft as opposed to certified ones. What does it stand for ?
>
> Owner Built Amateur Made or something ?
>
> Kent
>
>
________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
>
>I keep seeing the acronym OBAM. It 's obviously referring to amateur
>built aircraft as opposed to certified ones. What does it stand for ?
It's the sound made by an airplane builder when he discovers tab A does not
fit in slot B.
Dave Morris
________________________________________________________________________________
From: | Joe Dubner <jdubner(at)yahoo.com> |
Subject: | Re: OV protection for internally regulated alternators |
On 04-Feb-04 11:48 Clay R wrote:
> I personally feel like I am being blamed for "not
> knowing" that I shouldn't have switched off the
> alternator switch while the engine was running.
[... deleted ..]
> Please, speak up if you have your flying plane wired
> like z-24 and have (or have not) seen any issues with
> it. Any additional data points will help.
Clay, if there's blame to be assigned (lets hope there isn't), I'll take
some too. My Long-EZ is wired like Z-24 and I've turned off my
alternator in flight many times and under vaying load conditions.
My reasons may not pass muster but what the heck, it's my airplane.
Some of these reasons are: 1) testing the operation of the alternator
contactor I added; I was horrified to discover that my purchased Long-EZ
had no way to disable the alternator in case of an electrical fire. 2)
Troubleshooting a noisy Aerospace Logic EGT indicator; it worked OK on
battery but noise from the alternator caused readings to vary. 3)
Simulating alternator failure in flight; I wanted to see what it was
like to fly battery only to my destination before it actually happened.
No big deal.
FWIW, my alternator has no identifying marks other than a "Hitachi"
label. Perhaps I've just been lucky but I didn't know this was an issue
either.
Thank you for bringing this up and sharing your experience with the group.
--
Joe
Long-EZ 821RP
Gilbert, AZ
________________________________________________________________________________
From: | "AI Nut" <ainut(at)earthlink.net> |
Subject: | Re: start up/shut down procedure |
Web site?
----- Original Message -----
From: "Rick Johnson" <ricklj(at)silverstar.com>
Subject: AeroElectric-List: start up/shut down procedure
>
> Bob: I am wiring my RV7 according to your Z-13 and Z-24 diagrams. The
> only exception is I am using a 2-3 switch for my battery/alternator field
> switch instead of your 2-10. I would like to know what the proper start
up
> - system check - shut down procedure should be. How should I check to see
> if the SD-8 alternator is working correctly after the engine is running?
> What will the ammeter on that circuit read if the auxiliary alternator
> switch is off? Sounds like after start up, I wouldn't want to switch off
> the battery/primary alternator then switch on the e-bus and auxiliary
> alternator to see if it is carrying the system load properly. I'm
confused
> and would rather get some good advice from you before ruining some
> expensive equipment. And thanks for your fantastic web site and all the
> great advice you dispense here.
>
> rick
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | OV protection for internally regulated alternators |
>
>On 04-Feb-04 11:48 Clay R wrote:
>
> > I personally feel like I am being blamed for "not
> > knowing" that I shouldn't have switched off the
> > alternator switch while the engine was running.
>
>[... deleted ..]
>
> > Please, speak up if you have your flying plane wired
> > like z-24 and have (or have not) seen any issues with
> > it. Any additional data points will help.
>
>Clay, if there's blame to be assigned (lets hope there isn't), I'll take
>some too. My Long-EZ is wired like Z-24 and I've turned off my
>alternator in flight many times and under vaying load conditions.
. . . if your alternator is a junk-yard take-off, it's
quite likely to have the factory original voltage regulator
in it. It's hard to tell without a teardown under experienced
eyeballs.
>My reasons may not pass muster but what the heck, it's my airplane.
>Some of these reasons are: 1) testing the operation of the alternator
>contactor I added; I was horrified to discover that my purchased Long-EZ
>had no way to disable the alternator in case of an electrical fire. 2)
>Troubleshooting a noisy Aerospace Logic EGT indicator; it worked OK on
>battery but noise from the alternator caused readings to vary. 3)
>Simulating alternator failure in flight; I wanted to see what it was
>like to fly battery only to my destination before it actually happened.
> No big deal.
. . . and it shouldn't be.
>FWIW, my alternator has no identifying marks other than a "Hitachi"
>label. Perhaps I've just been lucky but I didn't know this was an issue
>either.
>
>Thank you for bringing this up and sharing your experience with the group.
Thanks for your input Joe.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>
> >
> >I keep seeing the acronym OBAM. It 's obviously referring to amateur
> >built aircraft as opposed to certified ones. What does it stand for ?
>
>It's the sound made by an airplane builder when he discovers tab A does not
>fit in slot B.
Good one Dave! I'll have to remember that. I'm working
on a white paper for the small aircraft directorate dealing
with ageing aircraft issues. We'll start with alternators
and batteries. I'm trying to drive home the point that
aside from mechanical issues where things break loose and
jam other things, neither of these items is by itself
critical to flight. I've introduced the term OBAM to the
FAA in this paper. Never can tell, it might germinate and
take hold. The NEXT step is "CBOM" . . . commercially built,
owner maintained. My dream machine is a Piper Pacer or Tri-Pacer
with NICE front seats, a hell-of-a-cargo pad where the back
seats used to be and a Z-13 electrical system.
I think I could have a really nice mogas, x-country machine
for well under $40K with a whole lot less build-time than
starting from scratch.
Bob . . .
________________________________________________________________________________
From: | Jim Oke <wjoke(at)shaw.ca> alternators / ND alternator |
Subject: | Re: OV protection for internally regulated |
alternators / ND alternator
ND alternator
After following the Vans Nippon Denso saga for a day or so, I wonder if
anyone can comment on the smaller Denso alternator that AeroSport Power
supplies with their engines as an option.
The one I received has a Nippon Denso tag as P/N 18504-6220 although it
seems to be manufactured by Ishikawajima as P/N 100211-1680 and marketed by
Denso. It has a B+ supply and can be run on a "single wire" control basis
although there is a warning light connection as well.
The unit has worked well in my limited flying to date (RV-6A). I am using a
homebrew OVM with a B field contactor.
And, no, I haven't experimented with a "battery dump" failure mode
experiment as yet.
Jim Oke
RV-6A
RV-3
Wpg, MB
----- Original Message -----
From: "Steve Sampson" <SSampson.SLN21(at)london.edu>
Subject: RE: AeroElectric-List: Re: OV protection for internally regulated
alternators / ND alternator
>
> Michael/Bob, The alternator VANS shipped to me IS a refurb Nippon Denso
> (Spelling?) alternator. It is the one on p7 of the 2003 accesory
catalogue.
> I had suggested the 35Amp externally regulated one but they suggested this
> was a better bet and lighter.
>
> Steve.
>
> -----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
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Re: OV protection for internally regulated
> alternators
>
>
>
>
> >
> >That battery dump damage thing... is this only related
> >with the alternators from Vans, or any automotive
> >alternators (including the Nippodensos found in
> >japanese cars)?
> >
> >Is this a certainty that it will fail each time, or is
> >it once in a lifetime that this will happen?
> >
> >Thanks!
> >
> >Michel
>
> Z-24 has been published for several years. I have
> to believe there have been a lot of systems installed
> and are flying. The questions are:
>
> (1) how many alternators are subject to this failure
> because their internal regulators are not rated for
> the battery-dump stress?
>
> (2) how many builders have put their particular
> alternator "to the test" by cycling the alternator
> control switch while the alternator was working
> hard?
>
> There are so many variables here that a truly
> quantitative response to your question cannot be
> deduced from what we know.
>
> I'm not sure which alternator Van's is selling.
> I THOUGHT it was an ND alternator. Does anyone
> know?
>
> It does take a combination of conditions to
> trigger the event:
>
> (1) relatively old design for built in regulator
> that is NOT protected from the battery-dump
> transient.
>
> (2) size of the transient is a function of how
> fast alternator is running and at what load
> when the connection between b-lead and battery
> is broken.
>
> When fitted with rudimentary electrical system
> instrumentation (low volts warning light or
> a voltmeter) there is no practical need or
> routinely exercised practice that calls for
> opening the alternator disconnect contactor
> while the engine is running IRRESPECTIVE
> of alternator vulnerability.
>
> If EVERY airplane I've ever rented over the
> past 23 years had been vulnerable to this
> failure mode, I'm 99.9% certain that the mode
> would not have been triggered while I was
> using the airplane . . . i.e. I've never
> had a situation arise where it was valuable
> or even interesting to operate the switch
> with the engine running.
>
> At the moment, my sense is that given the way
> MOST of us were taught (or not) on how
> to operate the airplane, the risks to even
> vulnerable alternators is quite low.
>
> The risk can be driven essentially zero once
> the magnitude of the transient is characterized
> and prophylactic measures implemented. At this
> point in the investigation, it would be a sad
> thing for a builder to jerk his perfectly working
> alternator off in knee-jerk response to truthful
> but poorly quantified warnings from well meaning
> folks who don't understand the system.
>
> Bob . . .
>
>
> ---
> Incoming mail is certified Virus Free.
>
> ---
>
>
________________________________________________________________________________
From: | "LarryRobertHelming" <lhelming(at)sigecom.net> |
Subject: | BNC bulkhead pass-through connectors |
In this reference, http://www.mpja.com/listitems.asp?dept=93&main=83 under
the sub heading of GENDER CHANGER BNC CONNECTOR are two items that I do not
understand and would like some help with what ISOLATED and NOT Isolated
means with respect to BNC connectors.
Larry
________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
Subject: | Re: BNC bulkhead pass-through connectors |
I'm relatively sure it describes whether or not the outer conductor (where
the shield connects) is isolated from the panel mounting hardware or not.
Dave Morris
At 06:16 PM 2/4/2004, you wrote:
>
>
>In this reference, http://www.mpja.com/listitems.asp?dept=93&main=83 under
>the sub heading of GENDER CHANGER BNC CONNECTOR are two items that I do not
>understand and would like some help with what ISOLATED and NOT Isolated
>means with respect to BNC connectors.
>
>Larry
>
>
________________________________________________________________________________
From: | Charlie Kuss <chaskuss(at)bellsouth.net> |
Subject: | Re: Converting a Denso Alternator #2 |
At 10:51 PM 2/3/2004, you wrote:
>
>
>I have a couple of Denso Alternators that I want to convert to nonregulated alternators.
I've seen a few different sites that discribe how to do this, but
not one that has the same type of regulator that are on my alternators. Both
alternators I have have a plastic regulator/plug housing. There are cooling
The regulator bolts to the diodes and brushes. I'm sure someone has done one
of these alternators, I was at the junk yard today and many of the import cars
used an alternator of this disign. I have some photos if that helps.
>
>
>Thanks for any help.
>
>
>Cameron
________________________________________________________________________________
From: | Charlie Kuss <chaskuss(at)bellsouth.net> |
Subject: | Re: Converting a Denso Alternator #3 |
Cameron,
As you will read in the article, the author shows how to convert both the Nippon
Denso models and the Mitsubishi units as well.
Charlie
>
>
>I have a couple of Denso Alternators that I want to convert to nonregulated alternators.
I've seen a few different sites that discribe how to do this, but
not one that has the same type of regulator that are on my alternators. Both
alternators I have have a plastic regulator/plug housing. There are cooling
The regulator bolts to the diodes and brushes. I'm sure someone has done one
of these alternators, I was at the junk yard today and many of the import cars
used an alternator of this disign. I have some photos if that helps.
>
>
>Thanks for any help.
>
>
>Cameron
________________________________________________________________________________
From: | Charlie Kuss <chaskuss(at)bellsouth.net> |
Subject: | Re: Converting a Denso Alternator #3 |
Sorry folks,
These last 2 posts were intended for Cameron off list. I've had a long hard day.
I'm now "officially" brain dead! :-(
Charlie Kuss
>
>Cameron,
> As you will read in the article, the author shows how to convert both the Nippon
Denso models and the Mitsubishi units as well.
>Charlie
>
>>
>>
>>I have a couple of Denso Alternators that I want to convert to nonregulated alternators.
I've seen a few different sites that discribe how to do this, but
not one that has the same type of regulator that are on my alternators. Both
alternators I have have a plastic regulator/plug housing. There are cooling
The regulator bolts to the diodes and brushes. I'm sure someone has done one
of these alternators, I was at the junk yard today and many of the import cars
used an alternator of this disign. I have some photos if that helps.
>>
>>
>>Thanks for any help.
>>
>>
>>Cameron
>
>
________________________________________________________________________________
From: | "Dan Checkoway" <dan(at)rvproject.com> |
""
Subject: | EMI solution for Dynon? |
http://www.4emi.com
Has anybody seen or played with these? Sure seems like an incredibly
elegant way to go -- IF it works!
)_( Dan
RV-7 N714D
http://www.rvproject.com
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: start up/shut down procedure |
>
>Web site?
http://www.aeroelectric.com
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | OV protection for internally regulated alternators |
>alternators / ND alternator
>
>After following the Vans Nippon Denso saga for a day or so, I wonder if
>anyone can comment on the smaller Denso alternator that AeroSport Power
>supplies with their engines as an option.
>
>The one I received has a Nippon Denso tag as P/N 18504-6220 although it
>seems to be manufactured by Ishikawajima as P/N 100211-1680 and marketed by
>Denso. It has a B+ supply and can be run on a "single wire" control basis
>although there is a warning light connection as well.
>
>The unit has worked well in my limited flying to date (RV-6A). I am using a
>homebrew OVM with a B field contactor.
>
>And, no, I haven't experimented with a "battery dump" failure mode
>experiment as yet.
It's difficult to comment on any particular alternator until
we're sure as to true root cause of the failures. The working
hypothesis is that after-market regulators used by some
re-build shops may not be as robust as the factory originals
by ND and others.
Probably the most revealing question to ask your alternator
supplier . . . is this a new alternator or rebuilt? Not that
rebuilt are automatically suspect . . . there are undoubtedly
after-market regulators equal to OEM. Given that companies
like ND sell MILLIONS of alternators per year, they can't
afford a screwup that saves a few pennies per unit but
opens doors to a ton of warranty claims. The after-market
regulator folks are not so exposed. Their warranty covers
only the regulator that costs them under $1 to build and
they can always point to the fried chip and cry "load
dump!". How many folks are going to know it's something
the regulator SHOULD be able to tolerate?
Don't do any "experimenting" until we have some data
to work with. I've had conversation with two sets of
folks about some testing. It won't happen until late next
week at the earliest.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Connector for elevator trim servo |
>
>Photos and info on the Hirose connector I plan to use for the elevator trim
>servo are posted on my web site.
>
>http://users.aol.com/n67bt
>
>This thing looks like just the ticket. What do you think Bob N.?
>
>They cost around $14 for the pair.
Hirose is a good house. I've used their stuff on
several occasions when I needed lots of conductors
in a small package.
Bob . . .
________________________________________________________________________________
From: | "Richard E. Tasker" <retasker(at)optonline.net> |
Subject: | Re: BNC bulkhead pass-through connectors |
That is correct. Isolated means that the whole assembly that the BNC
connectors connect to is electrically isolated from the mounting
flange. Non-isolated means that the mounting flange is connected to the
part of the connector that connects to the shield of the coax.
Dick Tasker, RV9A #90572
Dave Morris wrote:
>
>I'm relatively sure it describes whether or not the outer conductor (where
>the shield connects) is isolated from the panel mounting hardware or not.
>
>Dave Morris
>
>
>At 06:16 PM 2/4/2004, you wrote:
>
>
>
>>
>>
>>In this reference, http://www.mpja.com/listitems.asp?dept=93&main=83 under
>>the sub heading of GENDER CHANGER BNC CONNECTOR are two items that I do not
>>understand and would like some help with what ISOLATED and NOT Isolated
>>means with respect to BNC connectors.
>>
>>Larry
>>
>>
>>
>>
>
>
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: EMI solution for Dynon? |
>
>http://www.4emi.com
>
>Has anybody seen or played with these? Sure seems like an incredibly
>elegant way to go -- IF it works!
They do work. I've had occasion to use them a couple
of times in the past 20 years. Problem is that they're
not cheap . . . and they use the same filtering technique
on all pins whether the pin is a source/victim potential
or not.
For the most part, I've found it more economical to filter
the pins that needed filtering with components appropriate
to that pin's signal duties.
Bob . . .
________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
Subject: | Re: EMI solution for Dynon? |
I'll believe it when I see the spectrum analyzer output. EMI is a complex
problem and I don't think those little things will do much good.
Dave Morris
At 09:39 PM 2/4/2004, you wrote:
>
>http://www.4emi.com
>
>Has anybody seen or played with these? Sure seems like an incredibly
>elegant way to go -- IF it works!
>
>)_( Dan
>RV-7 N714D
>http://www.rvproject.com
>
>
________________________________________________________________________________
From: | Jerzy Krasinski <krasinski(at)direcway.com> |
Subject: | Re: Converting a Denso Alternator |
I opened my internaly regulated Mitsubishi, and I found one irregular
block containing the brush holders and regulator, all epoxy potted
inside a fragile looking piece of plastic. I thought about milling out
the regulator but it is very difficult to hold that thing in the mill,
and it looked that I would have to make a new brush holder from
scratch. I have spent a day looking at it and I gave up. I put the
alternator back together and I will try to attach transorbs or a big
varistor for protection. The problem is that information about the
transients included in http://www.sto-p.com/pfp/pfp-transients.htm#load
is showing voltage approaching 100V and internal resistance of the
source between 0.1 and 1 ohm. That would imply that current through the
varistor or transorb limiting output voltage to several volts could
reach several hundreds amps. That does not seem to make any sense, I
would expect that the alternator would try to make the output current
equal to the current just before removal of the load, and such current
would reduce the peak voltage down to the normal output voltage.
I will connect the protective elements and we will see if it works.
Anyway, my Mitsubishi is nearly impossible to convert in a simple way.
But maybe somebody solved that problem? I would appreciate some info.
Thank you,
Jerzy
Mark Steitle wrote:
>
>
>
>>
>>
>>I have a couple of Denso Alternators that I want to convert to
>>nonregulated alternators.
>>
>>
>
>Cameron,
>I posted this procedure a while back, but couldn't find it in the
>archives. So, here is the procedure I used to convert my two ND
>alternators to external regulator mode.
>
>Mark
>=============================================
>Bob N. strongly recommends using externally regulated alternators only, or
>modifying the internal regulator models so as to allow it to be shut down
>if necessary. (Supposedly, a voltage run-away can happen in a few seconds.)
>Problem is that the articles I read explaining how to convert the
>internally regulated alternators to external regulation didn't work. (Did I
>do something wrong?) I think I have worked out a simpler solution. The
>objective here is to isolate the field windings from the diode bridge so
>that the alternator can then be externally controlled.
>
>This is how I went about converting my alternators. First I removed the
>back cover, exposing the diode bridge, regulator assy. and brush holder.
>Then removed the regulator and brush holder and threw the regulator assy in
>the trash. Next ........................
>
>
________________________________________________________________________________
From: | Charlie Kuss <chaskuss(at)bellsouth.net> |
Subject: | Re: Converting a Mitsu Alternator #2 |
The blurry photos are due to the fact that this article was faxed to me.
Charlie
>
>I opened my internaly regulated Mitsubishi, and I found one irregular
>block containing the brush holders and regulator, all epoxy potted
>inside a fragile looking piece of plastic. I thought about milling out
>the regulator but it is very difficult to hold that thing in the mill,
>and it looked that I would have to make a new brush holder from
>scratch. I have spent a day looking at it and I gave up. I put the
>alternator back together and I will try to attach transorbs or a big
>varistor for protection. The problem is that information about the
>transients included in http://www.sto-p.com/pfp/pfp-transients.htm#load
> is showing voltage approaching 100V and internal resistance of the
>source between 0.1 and 1 ohm. That would imply that current through the
>varistor or transorb limiting output voltage to several volts could
>reach several hundreds amps. That does not seem to make any sense, I
>would expect that the alternator would try to make the output current
>equal to the current just before removal of the load, and such current
>would reduce the peak voltage down to the normal output voltage.
>
> I will connect the protective elements and we will see if it works.
>
>Anyway, my Mitsubishi is nearly impossible to convert in a simple way.
>But maybe somebody solved that problem? I would appreciate some info.
>Thank you,
>Jerzy
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Converting a Denso Alternator |
>
>
>I opened my internaly regulated Mitsubishi, and I found one irregular
>block containing the brush holders and regulator, all epoxy potted
>inside a fragile looking piece of plastic. I thought about milling out
>the regulator but it is very difficult to hold that thing in the mill,
>and it looked that I would have to make a new brush holder from
>scratch. I have spent a day looking at it and I gave up. I put the
>alternator back together and I will try to attach transorbs or a big
>varistor for protection. The problem is that information about the
>transients included in http://www.sto-p.com/pfp/pfp-transients.htm#load
> is showing voltage approaching 100V and internal resistance of the
>source between 0.1 and 1 ohm. That would imply that current through the
>varistor or transorb limiting output voltage to several volts could
>reach several hundreds amps. That does not seem to make any sense, I
>would expect that the alternator would try to make the output current
>equal to the current just before removal of the load, and such current
>would reduce the peak voltage down to the normal output voltage.
Your thinking rationally now Jerry, gotta be careful around
those who preach the gospel of doom-n-gloom. I think we know
that an alternator is incapable of delivering more than its
magnetics are designed for . . . even in a transient condition.
So a battery-dump event would be limited to perhaps 10-20% more
than the alternator's current rating. Also, I think the time
constants cited are rather long and predicated on effects of
system loads . . the effect we're intently interested in
is an intentionally generated battery-dump when the disconnect
contactor is opened and the alternator is totally unloaded.
Like you, I've read all the literature designed to convince
us that a happy world has transorbes sprinkled all over it,
and gee, if little ones are good, fat ones are better.
Let's keep stirring the pot with good science and repeatable
experiments. This can be good stew yet.
> I will connect the protective elements and we will see if it works.
Are you planning an experiment with measurements?
>Anyway, my Mitsubishi is nearly impossible to convert in a simple way.
>But maybe somebody solved that problem? I would appreciate some info.
That's not uncommon. The moldings that hold brushes and
regulators tend to be integrated in ways that make it
difficult to remove regulators and re-wire brushes.
Bob . . .
________________________________________________________________________________
From: | "Glen Matejcek" <aerobubba(at)earthlink.net> |
Subject: | ov protection for internal v.r. alternators |
Hi Bob and list-
Something has occurred to me. While I've never been inside a ND
alternator, and am certainly no guru of any sort, I have an idea I'd like
your feedback on. It seems to me that the fundamental problem with regard
to OV protection on these internally regulated alternators is the inability
to cut the supply of power to the field during an OV event. How hard /
appropriate would it be to open the regulator up, find the wire that feeds
the field, cut it, bring the two resultant lines out of the case to a relay
and a B&C OV module? When the system goes OV, power is removed from the
field. It seems so simple, I feel like I'm missing something....
gm
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: 11133 Hersha |
<5.0.0.25.2.20040204215217.015c1920(at)pop.central.cox.net>
>I haven't tried the separate battery yet, that's my next experiment. The
>radio noise does not go away if I disconnect the antenna - either radio,
>either antenna. Squelsh is automatic and not controlable from the front of
>the panel. I have 2 VAL COM 760's. Cheap radios, but I wanted 2 and I've
>never had a problem with them in the past.
. . . and I've never heard of them being a "problem" radio.
I'm thinking there may be something basic the architecture
of you system that's causing the problem.
>My kit from Radio Shack (I'm building 3) came with a 220 micro farad
>capacitor. Your plans diagram shows a 10 micro farad capacitor to be used.
>Should I use the one supplied or go get the 10 micro farad?
the kit should have come with the 10uf cap. If you have larger
caps you want to use, that's fine too.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>Sorry, but I've researched myself into a state of confusion and was hoping
>you guys could help me out.
>
>I'm not to the point of installing avionics yet, but a buddy is finishing
>up his RV-6 and is asking for help finishing up his avionics install. I've
>got connectors and tools (fancy stripper and crimper) for RG-58 cable, but
>he is using RG400. I've never worked with RG400 before.
>
>First, the connectors. I've seen some sites that indicate a single
>connector for RG58 or RG400. Other sites specify a different connector for
>the two. Is there really that big of a difference? It seems like there is
>no reasonable way to tie to the second shield in the RG400 anyway with a
>crimp connector.
It depends on the tolerances of the specific connector. MOST connectors
for RG400 will work with RG58 also. The connectors and tools offered
by B&C work with both coaxes.
>The other question on the stripper. It's one where you rotate a die for
>RG6/RG58/RG59. It seems reasonable to me that the blades could be
>adjusted, if necessary, with the RG58 position to get a good strip on the
>RG400. Again it kind of depends on the second shield on the RG400.
Yup, I've got a stripper that was supposedly set up for
RG58 and it does a better job on 400. A little practice
with a scrap of RG400 with an Xacto and #11 blade will
do good too.
Bottom line is don't make the first attempt at a new
combination of tools and technologies the one that
goes on your airplane. Get some extra connectors, pins,
etc and see how well they work and what techniques
you may need to refine to do the best job.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | ov protection for internal v.r. alternators |
>
>
>Hi Bob and list-
>
>Something has occurred to me. While I've never been inside a ND
>alternator, and am certainly no guru of any sort, I have an idea I'd like
>your feedback on. It seems to me that the fundamental problem with regard
>to OV protection on these internally regulated alternators is the inability
>to cut the supply of power to the field during an OV event. How hard /
>appropriate would it be to open the regulator up, find the wire that feeds
>the field, cut it, bring the two resultant lines out of the case to a relay
>and a B&C OV module? When the system goes OV, power is removed from the
>field. It seems so simple, I feel like I'm missing something....
Any modification to that end would be satisfactory . . . once you're
inside, it's just about as easy to completely remove the built in
regulator and bring out the field leads like the B&C mods.
After that, you have MANY options for regulators and ov protection.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | Jerzy Krasinski <krasinski(at)direcway.com> |
Subject: | Re: Converting a Denso Alternator |
Jerzy Krasinski wrote:
I will connect the protective elements and we will see if it works.
Robert L. Nuckolls, III wrote:
> Are you planning an experiment with measurements?
>
>
>
I just got a bunch of protective diodes and the biggest varistors I
could get for a reasonable price. Unfortunately there is a 20X price
jump for really big ones. However, it seems much more cost effective to
put several smaller varistors in parallel.
The choise between the diodes and varistors is difficult. Varistors are
almost indestructible, but they have more gradual characteristics. That
means they are likely to allow a bigger voltage increase in the
conditions of a dump. Diodes have sharper current increase with voltage,
but they are more fragile and they fail making a short, if they get too
much energy. Such a short would not be nice. The solution is to put
many of them in parallel - if I can isolate several similar diodes from
the bunch I got..
In the mean time I keep reading whatever was written about the
alternators. I do not have at home capabilities to check the protective
devices in a pulsed way for high current. I will try to do that
somewhere else. I will select more promising elements and attach them to
the alternator hoping for the best.
Jerzy
________________________________________________________________________________
From: | "Scott Hersha" <shersha(at)fuse.net> |
Subject: | Re: 11133 Hersha <5.0.0.25.2.20040204215217.015c1920(at)pop.central.cox.net> |
Bob, I'm making 3 of the noise filters I got at Radio Shack, however they
will not be as pretty as the one you made. When I snipped the choke leads
shorter per plans I was left with two untinned copper wires. It was nearly
impossibe to get solder to stick to the bare copper when soldering a tinned
wire to it. I'm using a 30 watt iron and the kind of solder you
recommended. The next two I made, I didn't cut the choke leads down so I
could use the tinned ends. I had to wrap the choke wires over the top and
glue the cap on the other side of the coil. I'll still run the wires
through the coil gap and use a lot of glue to provide strain relief, but it
will be a little less professional looking than yours. I just hope it
works.
Scott Hersha
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: AeroElectric-List: Re: 11133 Hersha
<5.0.0.25.2.20040204215217.015c1920(at)pop.central.cox.net>
>
> >I haven't tried the separate battery yet, that's my next experiment. The
> >radio noise does not go away if I disconnect the antenna - either radio,
> >either antenna. Squelsh is automatic and not controlable from the front
of
> >the panel. I have 2 VAL COM 760's. Cheap radios, but I wanted 2 and
I've
> >never had a problem with them in the past.
>
> . . . and I've never heard of them being a "problem" radio.
> I'm thinking there may be something basic the architecture
> of you system that's causing the problem.
>
> >My kit from Radio Shack (I'm building 3) came with a 220 micro farad
> >capacitor. Your plans diagram shows a 10 micro farad capacitor to be
used.
> >Should I use the one supplied or go get the 10 micro farad?
>
> the kit should have come with the 10uf cap. If you have larger
> caps you want to use, that's fine too.
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "James E. Clark" <james(at)nextupventures.com> |
Subject: | OV Protection for Internally Regulated .. Another Question |
There has been a LOT of dialog along the lines mentioned below (opening up
the alternator). I have looked but probably overlooked it so my question is:
Is there a *summary* recommendation (or opinion) on what one could
reasonably do to get additional protection WITHOUT opening the
alternator????
The one is question is the 55 amp model from Van's.
Thanks,
James
[snip]
> >
> >Something has occurred to me. While I've never been inside a ND
> >alternator, and am certainly no guru of any sort, I have an idea I'd like
> >your feedback on. It seems to me that the fundamental problem
> with regard
> >to OV protection on these internally regulated alternators is
> the inability
> >to cut the supply of power to the field during an OV event. How hard /
> >appropriate would it be to open the regulator up, find the wire
> that feeds
> >the field, cut it, bring the two resultant lines out of the case
> to a relay
> >and a B&C OV module? When the system goes OV, power is removed from the
> >field. It seems so simple, I feel like I'm missing something....
>
> Any modification to that end would be satisfactory . . . once you're
> inside, it's just about as easy to completely remove the built in
> regulator and bring out the field leads like the B&C mods.
>
> After that, you have MANY options for regulators and ov protection.
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "hollandm" <hollandm(at)pacbell.net> |
Subject: | Shielded wire options |
In choosing shielded wire to hook up the radio jacks I've used some relatively
inexpensive stuff that I found. Rather than the hightech stuff with braided shields
this wire has a mylar foil, with a bleed wire. Is this an acceptable to
use for audio hookups? I'm intend to use it to connect the Dynon external mag
compass, which has been alleged to induce EMI problems.
I don't want to cut corners when it makes a difference in safety, performance or
reliability.
Thanks
________________________________________________________________________________
From: | Jan de Jong <jan.de.jong(at)xs4all.nl> |
Subject: | Re: 11133 Hersha |
"It was nearly impossibe to get solder to stick to the bare copper when
soldering a tinned wire to it."
You may have to scrape the "bare copper" to get to the bare copper...
Jan de Jong
________________________________________________________________________________
aeroelectric-list(at)matronics.com
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Flap breaker size |
<5.0.0.25.2.20040106090414.01a21320(at)pop.central.cox.net>
<5.0.0.25.2.20040107094407.01613008(at)pop.central.cox.net>
<5.0.0.25.2.20040108104000.01b115f0(at)pop.central.cox.net>
<5.0.0.25.2.20040114094816.01b2d630(at)pop.central.cox.net>
<5.0.0.25.2.20040126085640.01a85e40(at)pop.central.cox.net>
<5.0.0.25.2.20040126221300.01a651b8(at)pop.central.cox.net>
>Hi Bob
>I have that flap motor working now but think I may have a problem with the
>circuit breaker. As you remember, I had the panel built and installed
>"acres of breakers"...this was PB (pre-Bob). They used a 15 amp CB for the
>flap circuit. Zenith showed a 5 amp breaker on their drawing. You used a
>10 amp breaker on your drawing...I am using a 16 ga wire as you drew in your
>schematic to the main bus.
>
>With this set-up, should I trade out the 15 amp breaker?
>
>Dale
The Z-drawings are for describing architecture. The
final selection for circuit protection has to be based
on load analysis of the particular accessory being
protected. If you have 16AWG run in, put a 10A breaker
on it for now. Let's do some real measurements during
your flyoff to see if the breaker is the right size.
The recommendations by most kit suppliers for electrical
issues are based on hearsay and seldom on calculations
or measurements to refine the design.
I will invite you to join us on the AeroElectric List
to continue this and similar discussions. It's useful to
share the information with as many folks as possible.
A further benefit can be realized with membership on
the list. There are lots of technically capable folks
on the list who can offer suggestions too.
Thanks!
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Shielded wire options |
>
>In choosing shielded wire to hook up the radio jacks I've used some
>relatively inexpensive stuff that I found. Rather than the hightech stuff
>with braided shields this wire has a mylar foil, with a bleed wire. Is
>this an acceptable to use for audio hookups? I'm intend to use it to
>connect the Dynon external mag compass, which has been alleged to induce
>EMI problems.
>
>I don't want to cut corners when it makes a difference in safety,
>performance or reliability.
The "Beldfoil" shield is electrically superior to braided
shield when it comes to electrical characteristics that
define shielding effectiveness. It's just not available in
tefzel insulated conductors. It will be fine for the application
you proposed.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> .. Another Question |
Subject: | Re: OV Protection for Internally Regulated |
.. Another Question
.. Another Question
>
>
>There has been a LOT of dialog along the lines mentioned below (opening up
>the alternator). I have looked but probably overlooked it so my question is:
>
>Is there a *summary* recommendation (or opinion) on what one could
>reasonably do to get additional protection WITHOUT opening the
>alternator????
>
>The one is question is the 55 amp model from Van's.
Yup, Figure Z-24 in the back of the AeroElectric Connection
suggests a means for providing (1) absolute control of an
internally regulated alternator and (2) providing ov
protection. The question under consideration now is which,
if any, alternators would do better with some means of
filtering off the "load dump" phenomenon that seems to be
responsible for damaging the regulators in some alternators.
Risk of damage is VERY low if one observes simple operating
protocols for panel switches that is consistent with the
way these switches are operated 99.999% of the time anyhow.
We may be able to drive the risk to essentially zero by
(1) selecting alternators with regulators already immune
to the load-dump phenomenon (as most OEM automotive products
probably are) or (2) a judicious addition of devices to
the alternator designed to address the physics of the
phenomenon in a well considered manner.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
Subject: | Re: OV protection for internally regulated alternators |
From: | Jack Bloodgood <jackb(at)us.ibm.com> |
21, 2004) at 02/06/2004 10:26:42
Hello,
Just a thought that where appropriate we might profit from the marine
industry. Almost all private boats have a battery switch which isolates the
battery and alternator. They have found that alternator diodes blow when
this switch is opened while the field windings are still energized. The
alternator is charging into an open circuit.
An internally regulated alternator wired as Z-24 with the alternator
disconnect contactor looks to have the same problem. The solution that the
marine industry has developed is the Zap-Stop, which appears to be Bob's
proposed solution in
http://www.aeroelectric.com/articles/Alternator_Failures.pdf
Might be something to consider. Make sure you get all of the URL:
http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-1&catalogId=10001&productId=46596&catalogId=10001&classNum=12105&subdeptNum=544&storeNum=9
Jack Bloodgood
Just a Lurker
jackb(at)us.ibm.com
________________________________________________________________________________
From: | Richard Tasker <retasker(at)optonline.net> |
Subject: | Re: 11133 Hersha |
What he is saying is that the coil probably uses magnet wire. This wire
has a very thin insulation similar to varnish and is similar in color to
the copper. You have to scrape this insulation off if you want to
solder to the copper wire.
Dick Tasker
Jan de Jong wrote:
>
>
>"It was nearly impossibe to get solder to stick to the bare copper when
>soldering a tinned wire to it."
>
>You may have to scrape the "bare copper" to get to the bare copper...
>
>Jan de Jong
>
________________________________________________________________________________
From: | "James E. Clark" <james(at)nextupventures.com> |
Subject: | OV Protection for Internally Regulated .. Another |
Question
Thanks Bob.
I had overlooked it.
James
[snip]
>
> Yup, Figure Z-24 in the back of the AeroElectric Connection
> suggests a means for providing (1) absolute control of an
> internally regulated alternator and (2) providing ov
> protection. The question under consideration now is which,
>
________________________________________________________________________________
From: | "Kenneth Gresham" <kgresham(at)mtco.com> |
Subject: | Navigatin lighting |
I would like to know what is required lighting in U.S. for night VFR and later
possibly IFR. Is wing lighting with colored front, strobe center, and white at
rear of same fixture adequate? If not please give lights and specific locations.
I would like to keep wiring to rear of fuselage to a minimum. I intend to
run wing tip wiring through a conduit since this is a composite airframe Any other
thoughts or suggestions are appreciated.
Ken Gresham
Europa Kit # A268 Rigging wings
________________________________________________________________________________
From: | "Scott Hersha" <shersha(at)fuse.net> |
Subject: | Re: Navigatin lighting |
Night flying requires navigation lights (red/left, green/right), white tail
lights, and an aniti-collision lighting system for the exterior of the
airframe. The tail lights can be the aft facing white light that is on many
nav light setups. There would be a light fixture on each wingtip with a red
or green light forward and the white light aft. These also come (very
popular) with a strobe light on the end of the fixture. The strobe lights
take the place of the anti-collision light that would otherwise have to
located somewhere on the fuselage, making it visible for 360 degrees. You
also need adequate lighting to read required flight and engine instruments
in the cockpit. No difference for IFR except I think you might also need to
have landing light....I wouldn't want to fly at night without them. If you
have an Aircraft Spruce catalog, check out the lighting section. There is a
good description of required exterior lighting as well as where they need to
be mounted for proper coverage. You don't need to have any lights on your
tail.....not required.
Scott Hersha
----- Original Message -----
From: "Kenneth Gresham" <kgresham(at)mtco.com>
Subject: AeroElectric-List: Navigatin lighting
>
> I would like to know what is required lighting in U.S. for night VFR and
later possibly IFR. Is wing lighting with colored front, strobe center, and
white at rear of same fixture adequate? If not please give lights and
specific locations. I would like to keep wiring to rear of fuselage to a
minimum. I intend to run wing tip wiring through a conduit since this is a
composite airframe Any other thoughts or suggestions are appreciated.
>
> Ken Gresham
> Europa Kit # A268 Rigging wings
>
>
________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
Subject: | Re: 11133 Hersha |
I used to light a match and flame the end of magnet wire and then the
varnish will crumple off into powder and wipe off easily. They may have
changed the chemical formulation since I did that last many years ago, but
it beat the heck out of sandpaper.
Dave Morris
At 09:44 AM 2/6/2004, you wrote:
>
>
>What he is saying is that the coil probably uses magnet wire. This wire
>has a very thin insulation similar to varnish and is similar in color to
>the copper. You have to scrape this insulation off if you want to
>solder to the copper wire.
>
>Dick Tasker
>
>Jan de Jong wrote:
>
> >
> >
> >"It was nearly impossibe to get solder to stick to the bare copper when
> >soldering a tinned wire to it."
> >
> >You may have to scrape the "bare copper" to get to the bare copper...
> >
> >Jan de Jong
> >
>
>
________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
Subject: | Re: Navigatin lighting |
At 04:56 PM 2/6/2004, you wrote:
>
>Night flying requires navigation lights (red/left, green/right), white tail
>lights, and an aniti-collision lighting system for the exterior of the
>airframe. The tail lights can be the aft facing white light that is on many
>nav light setups. There would be a light fixture on each wingtip with a red
>or green light forward and the white light aft. These also come (very
>popular) with a strobe light on the end of the fixture. The strobe lights
>take the place of the anti-collision light that would otherwise have to
>located somewhere on the fuselage, making it visible for 360 degrees. You
>also need adequate lighting to read required flight and engine instruments
>in the cockpit. No difference for IFR except I think you might also need to
>have landing light....I wouldn't want to fly at night without them. If you
>have an Aircraft Spruce catalog, check out the lighting section. There is a
>good description of required exterior lighting as well as where they need to
>be mounted for proper coverage. You don't need to have any lights on your
>tail.....not required.
>Scott Hersha
Also, if you're interested in saving weight, heat, and current, check out
the advances in LED technology that are happening. You've probably seen
the new car tail lights and traffic signals that use LEDs.
Here are just a few references on LEDs that should give you an idea of
what's developing and what's possible in experimental aviation:
Brightest LEDs are from Lumileds:
http://www.lumileds.com/luxeon/products/products_index.html
They can be purchased here, but only by phone, and check for what is in
stock before getting too excited:
http://www.quickar.com/leds.php
or from the authorized distributor here:
http://www.futureelectronics.com/1033/promos/lumileds/
Tail light kits:
http://www.periheliondesign.com/ledlightkits.htm
Position lights:
http://www.killacycle.com/Lights.htm
http://www.periheliondesign.com/ledpositionlights.htm
White paper on position lights:
http://www.periheliondesign.com/pdf_files/redandgreenledpositionlights.pdf
Research:
http://members.misty.com/don/led.html
http://ledmuseum.home.att.net/ledleft.htm
Dave Morris
________________________________________________________________________________
From: | "LarryRobertHelming" <lhelming(at)sigecom.net> |
Subject: | Re: Navigatin lighting |
You might want to pick up an Aircraft Spruce Catalog sometime. It has a
nice description of the lighting requirements.
Indiana Larry, RV7 Tip-up TMX-O-360 ACS2002 Dynon CNS430 Digitrak
On Finish Kit
----- Original Message -----
From: "Kenneth Gresham" <kgresham(at)mtco.com>
Subject: AeroElectric-List: Navigatin lighting
>
> I would like to know what is required lighting in U.S. for night VFR and
later possibly IFR. Is wing lighting with colored front, strobe center, and
white at rear of same fixture adequate? If not please give lights and
specific locations. I would like to keep wiring to rear of fuselage to a
minimum. I intend to run wing tip wiring through a conduit since this is a
composite airframe Any other thoughts or suggestions are appreciated.
>
> Ken Gresham
> Europa Kit # A268 Rigging wings
>
>
________________________________________________________________________________
From: | "hollandm" <hollandm(at)pacbell.net> |
Subject: | Shielded wire options |
Thanks Bob,
In that case I want to pass along this source of the least expensive wire that
will handle this application. They also stock various connectors and antenna
wire.
http://www.thewireman.com/index.shtml
________________________________________________________________________________
From: | Joel Harding <cajole76(at)ispwest.com> |
Subject: | ic-List:Power supply |
A short time ago a suggestion was given to hook up the power supply to
the B- lead to power up the airplane. Is there any need to disconnect
the alternator before power is applied?
Joel
________________________________________________________________________________
From: | klehman(at)albedo.net |
Subject: | alternator switch |
I still have trouble with the need for absolute alternator control or a
need for an alternator switch. I am referring to an internal vr
alternator. If ov protection trips then I don't want to reset it in
flight unless I suspect a nuisance trip. However nuisance ov tripping is
unacceptable so I would want to correct that or remove the ov
protection. If diodes short then the ANL is going to blow before I can
manually turn off the alternator. If I think that I might have time and
opportunity to turn it off before an impending crash then I'm pretty
sure that I'll already have the engine shutoff and I don't expect my
psru equipped engine to windmill so the alternator will already be dead.
At this point I'm leaning toward a manual battery switch that is not on
the panel so it can't be accidently turned off and no alternator switch.
I'm still thinking about it but such an architecture would also allow me
to run the electrically dependant engine loads through the manual batt
switch. But heh I'm still listening ;) ...
Another option that I'd like is for a reasonable cost replacement for
the heavy (weight and current) contactor that seems to be required to
add ov protection to my 40 amp alternator. With high current silicon
these days, I'd almost think that there would be a way of directly
crowbar shorting/blowing the B lead ANL. Hmmm now that I think about it
there might even be some 100+ amp scr's in my junk box... I think they
came from an AC/DC welder. Fortunately a lighter S704-1 relay seems to
be acceptable for my 20 amp second alternator.
Ken
Yup, Figure Z-24 in the back of the AeroElectric Connection
suggests a means for providing (1) absolute control of an
internally regulated alternator and (2) providing ov
protection.
________________________________________________________________________________
From: | Jerzy Krasinski <krasinski(at)direcway.com> alternators |
Subject: | Re: OV protection for internally regulated |
alternators
alternators
Jack Bloodgood wrote:
>
>
>Hello,
>
>Just a thought that where appropriate we might profit from the marine
>industry. Almost all private boats have a battery switch which isolates the
>battery and alternator. They have found that alternator diodes blow when
>this switch is opened while the field windings are still energized. The
>alternator is charging into an open circuit.
>
>
From the picture it looks that they are selling $0.70 transorb for $27.99.
Jerzy
________________________________________________________________________________
Subject: | Re: Shielded wire options |
From: | John Schroeder <jschroeder(at)perigee.net> |
You can buy RG400 Coax from Wiremaster for $0.86/ft (Min. of 100 ft order)
vs. $1.50 per ft. for a 100' buy at the source listed below. Wiremasters
also has every gauge of 22759 and in almost every color for prices below
any I have found. Most buys must be 100' min.
They also have milspec M27500-xx TG x T14 (shielded hookup wire). Their 22
AWG 5 conductor is $.94/ ft and their 3 conductor (M27500-22TG3T14) is
$.26 per foot.
Call them at 800 635-5342. Ask for Deb Sullivan. Or email her at
dsullivan(at)wiremasters.net
Cheers,
John
> In that case I want to pass along this source of the least expensive
> wire that will handle this application. They also stock various
> connectors and antenna wire.
>
> http://www.thewireman.com/index.shtml
>
________________________________________________________________________________
From: | "Terry Teer" <threet(at)telepak.com> |
Just about completed wings on a RV-7 and need some help. Installing landing light,
position light, strobes (in fiberglass tips), nav/com antenna wiring (RG-400),
also a roll servo for the a/p. Should I run all the wires through the 3/4
conduit or should some of them be separated from the rest? Also on the strobe
heads...the whelen strobes say to ground the shielding to the power supply
but in Bob's manual it says to ground the shielding wire to the strobe heads
if mounting in plastic tips. What about it list? This is my second OBAM and
the first to have more advanced equipment and need some advice.
Regards,
Terry
Ackerman, MS
________________________________________________________________________________
From: | "Gary Casey" <glcasey(at)adelphia.net> |
Subject: | RE: even more ov discussion |
<>
Here's an idea along those lines. If you have a single large (normal size)
battery and 2 alternators, make one be of very modest output, like 40 amps,
and the other a reasonable backup, like 8 or 20 amps. The failure mode will
be one of them going "ov." At that low capacity you will have plenty of
warning and will be able to increase the load (in my case 160W of landing
lights, pitot heat, vent blower) to reduce or even eliminate the excess
charge current to the battery. I'm not sure I'm recommending it, but it
does seem like a reasonable approach.
Gary Casey
________________________________________________________________________________
From: | Michel Therrien <mtherr(at)yahoo.com> |
Subject: | Battery Bus Power Cut Relay - good idea? |
Hi Bob!
I designed a modification this evening for my
electrical system. It is a dual-battery, single
alternator system for an automobile conversion engine
(converted for dual ignition).
I would like to know what you think of it.
Essentially, I propose a relay to cut the power from
the battery to the battery bus. That relay would be
wired so I use the normally-closed circuit and to open
(cut) the circuit when the coil is energized.
See (relevant portion of my electrical schema):
http://mthobby.pcperfect.com/mods/wirebook040208a.gif
A little modification to this would allow to cut all
voltage in the cabin from the flick of an emergency
cut-off switch.
See:
http://mthobby.pcperfect.com/mods/wirebook040208b.gif
Why this?
1. As per AeroElectric Connection, I want anything
that keeps the engine running to receive energy even
if I turn off the Master switch(es). Ign 1, 2 and
fuel pumps are on battery bus. And I want that engine
to continue working even if I make fool operation
(like turning off masters and then, on any switch that
would energize the engine).
2. It is recommended to use a relay to energize any
circuit from the B-Bus that is fused at more than
5amps. The reasoning is that we want to keep sparks
as small as possible when the aircraft is disingrating
during a crash. I'm not an expert at this, but I
think that no matter the size of a spark, the risk is
pretty much the same.
3. Two advisors here tell me it's important to be able
to cut all electrical power should I be in a situation
were crashing is a real possibility (ex.: lost engine,
going down in a rough field).
I think the modification should be reliable (but not
being an expert, this is why I ask for your opinion)
as I will be using the normally closed circuit from
the relay (b-bus ON when relay is NOT energized). It
will also be flexible as I still can turn off the
masters, use the battery busses and if needed, with
the second diagram, turn off all electrical system at
the flick of a single switch (protected with an
emergency switch cover).
More over, this change addresses your recommendation
of using relays for 5+amp all circuits with a single
relay.
Please let me know what you think.
Regards,
Michel
=====
----------------------------
Michel Therrien CH601-HD, C-GZGQ
http://mthobby.pcperfect.com/ch601
http://www.zenithair.com/bldrlist/profiles/mthobby
http://pages.infinit.net/mthobby
__________________________________
http://taxes.yahoo.com/filing.html
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: ectric-List:Power supply |
>
>
>A short time ago a suggestion was given to hook up the power supply to
>the B- lead to power up the airplane. Is there any need to disconnect
>the alternator before power is applied?
No.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: RE: even more ov discussion |
>
><need for an alternator switch. I am referring to an internal vr
>alternator.>>
>
>Here's an idea along those lines. If you have a single large (normal size)
>battery and 2 alternators, make one be of very modest output, like 40 amps,
>and the other a reasonable backup, like 8 or 20 amps. The failure mode will
>be one of them going "ov." At that low capacity you will have plenty of
>warning and will be able to increase the load (in my case 160W of landing
>lights, pitot heat, vent blower) to reduce or even eliminate the excess
>charge current to the battery. I'm not sure I'm recommending it, but it
>does seem like a reasonable approach.
Why put ov management on the pilots list of duties
when it so easy to make it automatic?
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> regulated alternators |
Subject: | Re: OV protection for internally |
regulated alternators
regulated alternators
> alternators
>
>
>Jack Bloodgood wrote:
>
> >
> >
> >Hello,
> >
> >Just a thought that where appropriate we might profit from the marine
> >industry. Almost all private boats have a battery switch which isolates the
> >battery and alternator. They have found that alternator diodes blow when
> >this switch is opened while the field windings are still energized. The
> >alternator is charging into an open circuit.
> >
> >
>
> From the picture it looks that they are selling $0.70 transorb for $27.99.
>Jerzy
I think you're right . . . and a transorb is exactly what I'm going
to propose. But I can't make a recommendation until after we've
tested the alternator and sized the part.
Bob . . .
________________________________________________________________________________
From: | frequent flyer <jdhcv(at)yahoo.com> |
Subject: | Re: RE: even more ov discussion |
> Why put ov management on the pilots list of
> duties
> when it so easy to make it automatic?
>
> Bob . . .
Hey guys, if you have an internally regulated
alternator and OV protection, use the alternator. If
you ever do have an overvoltage condition that blows
the alternator replace it with one that is not
internally regulated. If it never happens it doesn't
matter. I think you're wasting too much time worrying
about it. fwiw.
Jack
__________________________________
http://taxes.yahoo.com/filing.html
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: alternator switch |
>
>I still have trouble with the need for absolute alternator control or a
>need for an alternator switch.
How so? If you hardwire the alternator to the airplane
and it does go into an ov condition, how would you
expect to manage the results that follow?
> I am referring to an internal vr
>alternator. If ov protection trips then I don't want to reset it in
>flight unless I suspect a nuisance trip. However nuisance ov tripping is
>unacceptable so I would want to correct that or remove the ov
>protection.
Nuisance tripping of the crowbar ov module is rare but it
HAS happened and at higher rates than real ov tripping.
I'd have no problem with resetting an ov trip one time . . .
and then watching to see if any second trip is associated with
some action. (We could do it on Bonanzas by turning landing
and taxi lights on at the same time - I unaware of any dominant
nuisance trip modes since we modified the system to accommodate
eccentricities of the Bonanza'a super bouncy switches).
>If diodes short then the ANL is going to blow before I can
>manually turn off the alternator. If I think that I might have time and
>opportunity to turn it off before an impending crash then I'm pretty
>sure that I'll already have the engine shutoff and I don't expect my
>psru equipped engine to windmill so the alternator will already be dead.
I'm confused . . . why should your engine die just 'cause the
alternator misbehaves?
Diodes shorting are also very rare, even more rare than real
ov trips.
>At this point I'm leaning toward a manual battery switch that is not on
>the panel so it can't be accidently turned off and no alternator switch.
>I'm still thinking about it but such an architecture would also allow me
>to run the electrically dependant engine loads through the manual batt
>switch. But heh I'm still listening ;) ...
First, keep in mind that the "OV TRIP PROBLEM" seems to be shaping
up as a condition limited to rebuilt internally regulated alternators
with possible after-market regulators having poor design. I fully
expect the "fix" to be simple and probably inexpensive enough for
it to be included in the Figure Z-24 design for inclusion on ALL
internally regulated alternators irrespective of pedigree. If this
turns out to be true, then all of this discussion is making a mountain
out of a mole hill.
>Another option that I'd like is for a reasonable cost replacement for
>the heavy (weight and current) contactor that seems to be required to
>add ov protection to my 40 amp alternator. With high current silicon
>these days, I'd almost think that there would be a way of directly
>crowbar shorting/blowing the B lead ANL.
I've looked at direct crowbar of the alternator b-lead. You
DON'T want to do this with an ANL . . . we'd probably recommend
a relatively robust but MUCH faster JJS/JJN series fuse at 100A
or so. This still has pitfalls. Recall that a crowbar ov module
faulted downstream of a 5A breaker gets us trip responses in
the tens of milliseconds with a 300A fault. If we expected
similar speeds from a direct crowbar of the b-lead, we're going
to looking a fault currents on the order of 1000A or more.
The BATTERY is an integral component of the crowbar ov trip system.
We want it do deliver fault currents high enough to get a speedy
trip while minimizing disruption of power to the rest of the
airplane. Trip currents necessary to open the b-lead fuse are
substantially higher than those required to open a 5A control
breaker.
> Hmmm now that I think about it
>there might even be some 100+ amp scr's in my junk box... I think they
>came from an AC/DC welder. Fortunately a lighter S704-1 relay seems to
>be acceptable for my 20 amp second alternator.
I'm not saying what you're suggesting can't work but
there's more to it than deciding to "crowbar that fuse
instead of this breaker" . . . I've already looked at
some of the issues and there are aspects of b-lead
crowbar that push our design in the wrong direction.
The goal is to shut the alternator down with minimum
stress on all parts involved including battery and other
devices soon to be dependent on the battery for power.
In fact, Z-24 would work very nicely with a 2A control
breaker. THAT's indeed a move in the right direction.
Yes, the contactor adds some weight . . but keep in
mind that the weight penalty of the disconnect contactor
(12 oz) is less than the variability of popular alternators
being considered as alternatives to the MUCH heavier
alternators in certified aircraft. If you did the mod
to run an external regulator, you add 7-10 ounces for
the regulator. So, after saving 3-6 pounds by choosing
not to use contemporary certified alternators,
then the delta weight between externally regulated
and internally regulated alternator installations is
on the order of 2 to 5 ounces.
Bob . . .
________________________________________________________________________________
From: | Jim Oke <wjoke(at)shaw.ca> |
Subject: | Re: RE: even more ov discussion |
Well, that's about the size of it. Alternators of the sort being discussed
are quite cheap compared to the expensive avionics that the OV device is
intended to protect.
Worrying about a $75 alternator when the real money is in the $1000 radios
and the $3000 (and on up) GPS units is wasted time.
The whole idea of OV protection is to look after the expensive avionics and
the aircraft wiring and not to preserve some flaky alternator to live
another day. (Most modern automotive alternators are not flaky - and are
built to withstand all sorts of abuse from mechanically inept drivers on a
"they don't even have to know it's there" basis.)
Jim Oke
Wpg., MB
----- Original Message -----
From: "frequent flyer" <jdhcv(at)yahoo.com>
Subject: Re: AeroElectric-List: RE: even more ov discussion
>
>
> > Why put ov management on the pilots list of
> > duties
> > when it so easy to make it automatic?
> >
> > Bob . . .
> Hey guys, if you have an internally regulated
> alternator and OV protection, use the alternator. If
> you ever do have an overvoltage condition that blows
> the alternator replace it with one that is not
> internally regulated. If it never happens it doesn't
> matter. I think you're wasting too much time worrying
> about it. fwiw.
>
> Jack
>
________________________________________________________________________________
From: | "Dale Martin" <niceez(at)cableone.net> |
Subject: | Re: battery / alternator switch |
In the schematic's for the all electric airplane (Z-13) and the Generic
Light Aircraft Electrical System (Z-11) both depicts a Battery / Alt switch
# 2-10 - (2 dash 10). However, in the switches, relays and contactors pages
it says switch 2 dash 3 is recommend for the combination Battery
Master/alternator-field switching.
Which one is correct?
BTW, I have just successfully removed all wires from my 28volt IFR LEZ (with
exception of the strobe and nav light wires in the wings) after 18 years and
1,100 + hours of flying. Talk about scary.... This is for a much simplier
electrical system and full panel upgrade. No more vacuum system for me and
no more 28 to 14 inverter. Everything is 28 volt.
One thing I found amazing is how many different places I had ground wires
terminating. I built my own ground bus only because the ones from B&C do
not appear to be mechanically attached to the brass and my two boys needed
some practice using the drill press using brass. The total price was less
then twenty bucks with free labor.
Also this system will only be using one alternator. Using one mag and one
E.I is enough engine redundancy with the lone battery for essential bus. I
believe in the good battery theory and checking it twice per year for acid
specific gravity and over all battery condition and replacing it as needed.
Thanks for your help and comments in advance,
Dale Martin
Lewiston, ID
LEZ-235
________________________________________________________________________________
From: | "Dan Branstrom" <danbranstrom(at)verizon.net> |
Subject: | For Bob, Comment? |
There is an upcoming program on Public Broadcasting: NOVA: The Deadly Legacy Of
an inflight fire caused by electrical arcing.
Because the article is too long to send out, I'm referring you to the press release that can be seen on the Mon, 09 Feb '04 online edition of Aero News Network http://aero-news.net/index.cfm
________________________________________________________________________________
From: | "Dan Branstrom" <danbranstrom(at)verizon.net> |
Subject: | For Bob: Comment? |
Here is a more precise address for the article. References to the ANN website
will get different stories every day.
http://aero-news.net/index.cfm?ContentBlockIDca2fd051-b7b7-4fe2-94dc-def5c536d3d5&
There is an upcoming program on Public Broadcasting: NOVA: The Deadly Legacy Of
an inflight fire caused by electrical arcing.
(The web address that follows is the general one for ANN. To see the article,
you would have to refer to the date.
Because the article is too long to send out, I'm referring you to the press release that can be seen on the Mon, 09 Feb '04 online edition of Aero News Network http://aero-news.net/index.cfm
________________________________________________________________________________
From: | BAKEROCB(at)aol.com |
AeroElectric-List message previously posted by: "Terry Teer"
<>
2/8/2004
Hello Terry, The cable from Whelen has foil shielding and a drain wire in
addition to the other wires. Just connect the drain wire to the base of the
(central?) power supply like Whelen says. See previous post below. There are
follow up postings that hash this out some more that you can read using the search
capability if you desire.
'OC'
6/29/2003
Hello Bob Nuckolls and Bret Ferrell, I'd like to flog this horse a few more
lashes.
1) Bob Nuckolls really says the drain wire should be attached at both ends on
a composite aircraft? But not on a metal aircraft? Why?
2) When one receives the strobe light installation kit from Whelen the cable
already has two AMP plastic 3 wire connectors attached, one on each end. These
connectors are the ones that plug into the mating 3 wire connectors at the
strobe light ends. After cutting the cable somewhere in the middle and snaking
those two cut ends through the airframe to the vicinity of the strobe power
supply one installs the other two (different) appropriate 3 wire connectors
provided by Whelen and plugs the cables into the power supply.
3) The installation instructions say that the drain wire should be connected
to the housing / mounting of the power supply. Easy enough to do by leaving
the drain wire longer when you cut the cable, strip it, and install the 3 wire
connectors that plug into the power supply.
4) But out at the strobe light end of the cable where the Whelen installed
connectors are, Whelen has left no access to the drain wire. I suppose one could
cut back the plastic covering, remove the aluminum shield, attach a short
wire to the now exposed drain wire, and then attach that short wire to some metal
part of the strobe light housing, but I find this action both puzzling and
unnecessary.
5) Whelen has thousands of these units in service throughout the skies
mounted on both metal surfaces and composite wing tips. I am unaware of any need
to
go through the additonal effort of connecting the drain wire to the metal
light housing out at the strobe light end. Can anyone show me different?
________________________________________________________________________________
From: | "ivorphillips" <ivor(at)ivorphillips.flyer.co.uk> |
Subject: | Re: For Bob, Comment? |
> There is an upcoming program on Public Broadcasting: NOVA: The Deadly
It deals with an inflight fire caused by electrical arcing.
>
Have seen this program a couple of weeks ago, It make you wonder how a
commercial aircraft can have its wiring set up in such away that the pilots
were unable to isolate the entertainment system from the main cockpit Bus!
No breakers tripped to alleviate the problem, just smoke from behind
panelling,
I find it hard to believe that circuits are shared without proper regards
too overload wire protection, Its criminal that so many folk lost their
lives due to a preventable wiring short circuit.
Ivor Phillips
Europa xs
________________________________________________________________________________
From: | "Paul Messinger" <paulm(at)olypen.com> |
Subject: | Load dump issues |
I have watched this discussion and am concerned that the
issue/facts/solution is going off track a little.
Load dump is NOT unique to internally regulated alternators. ANY alternator
can and will exhibit load dump when wired such that the load can be removed
from the "B" lead when the alternator is generating power. IE
internal/external/new/old/rebuilt are all the SAME with regard to Load Dump
concerns.
All alternators, regardless of design, need protection or they can dump
damaging loads either back to the alternator or to the expensive avionics
depending on what opened and where.
Designs that disconnect the "B" lead when OVP is detected are great as long
as there are Zero false trips. Bob has said many times that his OVP can and
does (while very rare) false trip. This can result in alternator damage due
to a false trip and not acceptable to me.
Alternator damage with a real OVP trip is not an issue as the alternator has
already failed.
There are more modern OVP I/C's that have provision for not false tripping
on narrow spikes as they have adjustable delay to trip times. I suggest that
this design approach be used to prevent a OVP protection device from
causing damage from a not quite perfect design.
The Linear LTC1696 is inexpensive and is designed to provide reliable OVP
with minimal additional parts.
Eric Jones has such a OVP design and I highly recommend it IF you are
concerned about False trips. It's already designed and available to us.
http://www.periheliondesign.com/
If the alternator is generating say 50 amps and 40 amps are going to the
battery and 10 amps to the rest of the system and the battery is
disconnected the alternator output voltage (and the acft system bus) will
rise until the 40 amp excess is loaded. This can result in a high voltage
spike that is not stopped with OVP devices that shut off the regulator (too
late action). Thus potential damage to avionics etc is likely if there is a
large enough load dump. The damaging current is already there and thus its
too late for a working regulator with or without OVP design to stop the
energy pulse.
On the other hand if the battery is fully charged there will be near zero
current that is unloaded and no load dump to worry about if the battery is
suddenly off line. Also most alternator regulators will work properly with
out the battery if there is enough load on the system. Some may require a
large cap say 25,000 MFD to stabilize the regulator without the battery
present.
Load dump is not new; some 20+ years ago I/C mfgrs tried to convince auto
makers to incorporate Load dump protection in their alternators. This effort
was unsuccessful (at the time) as this is not an issue with autos, as in
autos the "B" lead is always directly wired to the battery. Thus there is no
"switch" to be accidentally opened to cause load dump action. Also there is
no OVP included as its rare and not a concern in the auto mfgrs mind. At
least a couple of years ago I was unable to find ANY auto mfgr alternator
that protected against load dump.
ANY design that uses an alternator and has a requirement to be disconnected
from the battery (as in acft) needs to be fool proof. Ideally there should
be no way to do it with the accidental throw of a switch as the current Z-xx
diagrams seem allow. At least without considering the potential of damaging
load dump. Again this info (load dump) and design need is decades old and I
wonder why its just becoming an issue on this list.
What we have is the USE of an auto alternator that was designed to be always
directly connected to the battery. In a different application with
additional design requirements to consider those new requirements have not
peen fully considered. Perhaps this is a continuation of what Spam can
mfgrs did when the generator was replaced with an alternator and the
replacement was not totally though out. Also at the time regulators were
mechanical and avionics had vacuum tubes and both are much more immune to
transients that today's solid state devices.
Bob has suggested that NEW alternators have such protection and so Bob
please let us know specifically which NEW alternators have such protection
built in so we can consider them for our use.
Then there are comments about rebuilt alternators being inferior. Perhaps
some are but then many are just as good as the original NEW alternator in
all respects.
As for testing and evaluation of TVS devices for load dump protection and
getting your stamp of approval why do it??
There are such devices available that are designed, tested and industry
approved for this specific application and rated for the largest alternator
likely to be found on any acft. The ST LDP24A is one and rated for 500amp.
I do not understand the need for additional testing in this case. The
Boaters have long since solved the problem and so why are we still
investigating it??
With all due respect my comments are intended to be helpful.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: alternator switch
>
> >
> >I still have trouble with the need for absolute alternator control or a
> >need for an alternator switch.
>
> How so? If you hardwire the alternator to the airplane
> and it does go into an ov condition, how would you
> expect to manage the results that follow?
>
> > I am referring to an internal vr
> >alternator. If ov protection trips then I don't want to reset it in
> >flight unless I suspect a nuisance trip. However nuisance ov tripping is
> >unacceptable so I would want to correct that or remove the ov
> >protection.
>
> Nuisance tripping of the crowbar ov module is rare but it
> HAS happened and at higher rates than real ov tripping.
> I'd have no problem with resetting an ov trip one time . . .
> and then watching to see if any second trip is associated with
> some action. (We could do it on Bonanzas by turning landing
> and taxi lights on at the same time - I unaware of any dominant
> nuisance trip modes since we modified the system to accommodate
> eccentricities of the Bonanza'a super bouncy switches).
>
> >If diodes short then the ANL is going to blow before I can
> >manually turn off the alternator. If I think that I might have time and
> >opportunity to turn it off before an impending crash then I'm pretty
> >sure that I'll already have the engine shutoff and I don't expect my
> >psru equipped engine to windmill so the alternator will already be dead.
>
> I'm confused . . . why should your engine die just 'cause the
> alternator misbehaves?
>
> Diodes shorting are also very rare, even more rare than real
> ov trips.
>
> >At this point I'm leaning toward a manual battery switch that is not on
> >the panel so it can't be accidently turned off and no alternator switch.
> >I'm still thinking about it but such an architecture would also allow me
> >to run the electrically dependant engine loads through the manual batt
> >switch. But heh I'm still listening ;) ...
>
> First, keep in mind that the "OV TRIP PROBLEM" seems to be shaping
> up as a condition limited to rebuilt internally regulated alternators
> with possible after-market regulators having poor design. I fully
> expect the "fix" to be simple and probably inexpensive enough for
> it to be included in the Figure Z-24 design for inclusion on ALL
> internally regulated alternators irrespective of pedigree. If this
> turns out to be true, then all of this discussion is making a mountain
> out of a mole hill.
>
>
> >Another option that I'd like is for a reasonable cost replacement for
> >the heavy (weight and current) contactor that seems to be required to
> >add ov protection to my 40 amp alternator. With high current silicon
> >these days, I'd almost think that there would be a way of directly
> >crowbar shorting/blowing the B lead ANL.
>
>
> I've looked at direct crowbar of the alternator b-lead. You
> DON'T want to do this with an ANL . . . we'd probably recommend
> a relatively robust but MUCH faster JJS/JJN series fuse at 100A
> or so. This still has pitfalls. Recall that a crowbar ov module
> faulted downstream of a 5A breaker gets us trip responses in
> the tens of milliseconds with a 300A fault. If we expected
> similar speeds from a direct crowbar of the b-lead, we're going
> to looking a fault currents on the order of 1000A or more.
>
> The BATTERY is an integral component of the crowbar ov trip system.
> We want it do deliver fault currents high enough to get a speedy
> trip while minimizing disruption of power to the rest of the
> airplane. Trip currents necessary to open the b-lead fuse are
> substantially higher than those required to open a 5A control
> breaker.
>
> > Hmmm now that I think about it
> >there might even be some 100+ amp scr's in my junk box... I think they
> >came from an AC/DC welder. Fortunately a lighter S704-1 relay seems to
> >be acceptable for my 20 amp second alternator.
>
> I'm not saying what you're suggesting can't work but
> there's more to it than deciding to "crowbar that fuse
> instead of this breaker" . . . I've already looked at
> some of the issues and there are aspects of b-lead
> crowbar that push our design in the wrong direction.
>
> The goal is to shut the alternator down with minimum
> stress on all parts involved including battery and other
> devices soon to be dependent on the battery for power.
> In fact, Z-24 would work very nicely with a 2A control
> breaker. THAT's indeed a move in the right direction.
>
> Yes, the contactor adds some weight . . but keep in
> mind that the weight penalty of the disconnect contactor
> (12 oz) is less than the variability of popular alternators
> being considered as alternatives to the MUCH heavier
> alternators in certified aircraft. If you did the mod
> to run an external regulator, you add 7-10 ounces for
> the regulator. So, after saving 3-6 pounds by choosing
> not to use contemporary certified alternators,
> then the delta weight between externally regulated
> and internally regulated alternator installations is
> on the order of 2 to 5 ounces.
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Kapton insulated wire . . . NOT a OBAM aircraft |
issue
>
>
>There is an upcoming program on Public Broadcasting: NOVA: The Deadly
>Legacy Of Swiss Air 111 that will be airing on February 17th at 8:00
>EST. It deals with an inflight fire caused by electrical arcing.
>
>Because the article is too long to send out, I'm referring you to the
>press release that can be seen on the Mon, 09 Feb '04 online edition of
>Aero News Network http://aero-news.net/index.cfm
Thanks for the heads up. I'll try to catch the program. I looked
over the linked article. It's writing typical of "journalists" who
don't know enough about the art and science of the topic to
write intelligently and accurately about it. It will be interesting
see how Nova presents it.
There was a lot of worry wash thrown about with paragraphs like this:
"NOVA reports the electrical arc, generating up to 12,000 degrees (F),
ignited the supposedly fireproof mylar insulation surrounding the interior
of the aircraft. The program quotes experts who say, in aircraft where
there's as much as 150 miles of wire on board, there can be up to 1500
cracks in wiring insulation. Couple that with the type of condensation
typical in the upper compartments of an aircraft in flight and NOVA's
experts suggest the possibility for a disastrous in-flight fire event are
extraordinary."
The discussion then shifts back to failures of policy and procedures
systems to deal with materials used in insulation and other
parts with emphasis on proposals to improve ability to detect and
suppress fires.
I didn't pick up on a single statement dealing with
why an airplane with 150 miles of wire should be reasonably
expected to have 1500 cracks . . . gee, the B-52's I worked
on in 1961 had 500 miles of wire . . . Hmmmm . . . should
we have told crews that their airplane had a good chance
of having 5,000 cracks in the wiring?
The 12,000 degrees (F of course . . . that's only 8,300
degrees C but not nearly as impressive a number) statement
is suspect and not particularly relevant without explaining
what the total energy budget is and how that bundle of energy
gets from the arc to surrounding materials.
Every time you open the pitot heater switch on your airplane,
an arc of very high temperature is generated . . . but with total
energy measured in millijoules and totally contained between
two rather cool contacts. A complete non-issue when
the complete picture is examined . . . but I could write
a paragraph describing the event that would have many
builders swearing never to install a pitot heater on
their airplane.
The article didn't mention Kapton insulation on wires
. . . which I've heard was involved in this accident.
See:
http://www.flight592.com/Flight592Discussion-Current/_disc5/00000158.htm
http://www.iasa.com.au/folders/Safety_Issues/Aircraft_Wire/CBCTranscript.html
Here's a piece the takes a better than average whack at the science:
http://www.eng.buffalo.edu/Courses/ce435/2001ZGu/Kapton_Wires/KaptonWiresReport.htm
I was warned about Kapton in 1985 when we were selecting
wire for the GP-180 at Lear and frustrated with the State
Department's prohibition against exporting 22759 wire
in a product. We certainly didn't want to limit the sales
of our airplanes to US customers. I was told back then
that the Navy was having to wrap wires at the hinges of
folding-wing carrier based aircraft with Scotch 33 tape
to replace Kapton that flaked off in the salt-air environment.
I doubt the B-52 had a few dozens of cracks in wiring much less
5,000. Airplanes wired with Tefzel have to rank among the
very best we know how to do for ease of installation,
reasonable cost, and well demonstrated service life.
The Swiss Air 111 accident will make good worry-fodder
for Nova and others for years to come but I'll be completely
amazed if anyone finally burrows down to the real root cause
and makes it public. It's more useful to bash the
policy and procedures guys for what they're NOT doing
to make us "safer" than to exposed the original designers
and installers of a marginally suitable product and make them
gut those airplanes and rewire them.
Characteristics of the mylar insulation and duct
caps don't worry me nearly so much as the kind of insulation
used on the wires.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: battery / alternator switch |
>
>In the schematic's for the all electric airplane (Z-13) and the Generic
>Light Aircraft Electrical System (Z-11) both depicts a Battery / Alt switch
># 2-10 - (2 dash 10). However, in the switches, relays and contactors pages
>it says switch 2 dash 3 is recommend for the combination Battery
>Master/alternator-field switching.
>
>Which one is correct?
Either one works. A 2-3 combined with a PULLABLE field supply breaker
in the crowbar ov protection circuit gives the same functionality as
a 2-10.
It's no big deal to have the alternator ON during cranking . . . so,
a 2-3 works.
-EITHER- the mid-position on a 2-10 switch -OR- pulling the field
circuit breaker allows battery only ops for ground maintenance or turning
off a mis-behaving alternator in flight. It's not a matter of CORRECTNESS
but a matter of PREFERENCE.
>BTW, I have just successfully removed all wires from my 28volt IFR LEZ (with
>exception of the strobe and nav light wires in the wings) after 18 years and
>1,100 + hours of flying. Talk about scary.... This is for a much simplier
>electrical system and full panel upgrade. No more vacuum system for me and
>no more 28 to 14 inverter. Everything is 28 volt.
Are you going to 14v or staying 28v?
>One thing I found amazing is how many different places I had ground wires
>terminating. I built my own ground bus only because the ones from B&C do
>not appear to be mechanically attached to the brass . . .
How so?
>and my two boys needed
>some practice using the drill press using brass. The total price was less
>then twenty bucks with free labor.
Also this system will only be using one alternator. Using one mag and one
>E.I is enough engine redundancy with the lone battery for essential bus. I
>believe in the good battery theory and checking it twice per year for acid
>specific gravity and over all battery condition and replacing it as needed.
Do you have a vacuum pump pad with nothing mounted on it?
For $300 and 4 pounds you can have a SECOND engine driven
power source.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Ned Thomas" <315(at)cox.net> |
I am looking at buying a float charger for my 24volt spam can. This spam can
has an always hot battery bus with the the ships clock on it. I was
concerned about the following marketing statement as to whether it might
harm the clock. Anyone care to comment?
Thanks,
Ned
"High-frequency pulse breaks down sulphated crystals that prevent batteries
from holding a full charge."
for more:
http://www.batterymart.com/battery.mv?p=VDC-24021
________________________________________________________________________________
From: | f1rocket(at)telus.net |
Subject: | Z12 e-bus questions |
Hi all (Bob),
I'm planning on using a Z-12 type system on my Rocket. One battery, two
alternators.
I notice the e-bus alternate feed is through a 7 A (fuse?) via a 16 AWG wire.
Two questions: For peace of mind would a breaker be the best way to go here?
I'm thinking that I can easily overload the 7 amps just with the e-bus as
described in Z-11. The plane will be outfitted for night flying, and needs a
fuel booster pump. So if I end up with more than 7 A (which either I will
have, or be very close to) when I loose the main power (assuming two dead
alternators), and throw the switch, at least I can get smart, shed load and
reset the breaker. For the most part though, I plan on using fuses, because I
too have never reset a breaker were there wasn't a problem that resetting the
breaker actually helped, and I plan on having each circuit with it's own fuse.
Second question: Why only 7 amp protection device off the batter bus? The
wire should be able to handle 12 amps? So why not use the protection device to
protect the wire, since each of the devices coming off the e-bus will be
protected on it's own?
Thanks in advance, and also for all the past advice.
Jeff
________________________________________________________________________________
From: | "Dale Martin" <niceez(at)cableone.net> |
Subject: | Re: battery / alternator switch |
Bob says,
> Do you have a vacuum pump pad with nothing mounted on it?
> For $300 and 4 pounds you can have a SECOND engine driven
> power source.
>
> Bob . . .
I think you mean a Third source. (Battery =1, Alt =2, Second Alt = 3)
I like the fact that I get 4 horsepower back at cruise RPM that the Vacuum
pump stole.
> Are you going to 14v or staying 28v?
I will keep 28 v due to the wire size I use are smaller and paid for! And
have a second full size Alternator on the shelf.
But to your credit I did consider it but..... then would have to change the
starter, Alt, Nav-Com 1, landing light, strobe power unit and all the bulbs
not to mention the LR3. Your talking over $2000 bucks and accepting peanuts
for some of the equipment I have now.
BTW, I have always started the engine with the Alt off.
One thing I think is an error IMHO is not using separate Ignition Switches
either Guarded or Locking toggle switch for magneto's and especially the
older LSE electronic ignitions. When the LSE E.I. are turned on they fire
all the plugs at once - Yikes ! May not be a good idea to do this at any
RPM. If you were to bump on off in-flight and turn it back on... and it
fired say 65 BTDC..... That would really mess things up. Klaus warned me
about it.
On the alternator thread .......
If the C/B on the LR3 field wire were pulled (engine running) is the Alt
able to still send out power just not regulated? If it does, that is not
good. I was taught without the field there is no power.
Thanks for your comments,
Dale Martin
Lewiston, ID
LEZ-235
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: battery / alternator switch
>
> >
> >In the schematic's for the all electric airplane (Z-13) and the Generic
> >Light Aircraft Electrical System (Z-11) both depicts a Battery / Alt
switch
> ># 2-10 - (2 dash 10). However, in the switches, relays and contactors
pages
> >it says switch 2 dash 3 is recommend for the combination Battery
> >Master/alternator-field switching.
> >
> >Which one is correct?
>
> Either one works. A 2-3 combined with a PULLABLE field supply breaker
> in the crowbar ov protection circuit gives the same functionality as
> a 2-10.
>
> It's no big deal to have the alternator ON during cranking . . . so,
> a 2-3 works.
>
> -EITHER- the mid-position on a 2-10 switch -OR- pulling the field
> circuit breaker allows battery only ops for ground maintenance or
turning
> off a mis-behaving alternator in flight. It's not a matter of
CORRECTNESS
> but a matter of PREFERENCE.
>
>
> >BTW, I have just successfully removed all wires from my 28volt IFR LEZ
(with
> >exception of the strobe and nav light wires in the wings) after 18 years
and
> >1,100 + hours of flying. Talk about scary.... This is for a much
simplier
> >electrical system and full panel upgrade. No more vacuum system for me
and
> >no more 28 to 14 inverter. Everything is 28 volt.
>
> Are you going to 14v or staying 28v?
>
> >One thing I found amazing is how many different places I had ground wires
> >terminating. I built my own ground bus only because the ones from B&C do
> >not appear to be mechanically attached to the brass . . .
>
> How so?
>
> >and my two boys needed
> >some practice using the drill press using brass. The total price was
less
> >then twenty bucks with free labor.
>
> Also this system will only be using one alternator. Using one mag and
one
> >E.I is enough engine redundancy with the lone battery for essential bus.
I
> >believe in the good battery theory and checking it twice per year for
acid
> >specific gravity and over all battery condition and replacing it as
needed.
>
> Do you have a vacuum pump pad with nothing mounted on it?
> For $300 and 4 pounds you can have a SECOND engine driven
> power source.
>
> Bob . . .
>
> -----------------------------------------
> ( Experience and common sense cannot be )
> ( replaced with policy and procedures. )
> ( R. L. Nuckolls III )
> -----------------------------------------
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Battery Bus Power Cut Relay - good idea? |
>
>Hi Bob!
>
>I designed a modification this evening for my
>electrical system. It is a dual-battery, single
>alternator system for an automobile conversion engine
>(converted for dual ignition).
>
>I would like to know what you think of it.
>Essentially, I propose a relay to cut the power from
>the battery to the battery bus. That relay would be
>wired so I use the normally-closed circuit and to open
>(cut) the circuit when the coil is energized.
>1. As per AeroElectric Connection, I want anything
>that keeps the engine running to receive energy even
>if I turn off the Master switch(es). Ign 1, 2 and
>fuel pumps are on battery bus. And I want that engine
>to continue working even if I make fool operation
>(like turning off masters and then, on any switch that
>would energize the engine).
>
>2. It is recommended to use a relay to energize any
>circuit from the B-Bus that is fused at more than
>5amps. The reasoning is that we want to keep sparks
>as small as possible when the aircraft is disingrating
>during a crash. I'm not an expert at this, but I
>think that no matter the size of a spark, the risk is
>pretty much the same.
>
>3. Two advisors here tell me it's important to be able
>to cut all electrical power should I be in a situation
>were crashing is a real possibility (ex.: lost engine,
>going down in a rough field).
>
>I think the modification should be reliable (but not
>being an expert, this is why I ask for your opinion)
>as I will be using the normally closed circuit from
>the relay (b-bus ON when relay is NOT energized). It
>will also be flexible as I still can turn off the
>masters, use the battery busses and if needed, with
>the second diagram, turn off all electrical system at
>the flick of a single switch (protected with an
>emergency switch cover).
>
>More over, this change addresses your recommendation
>of using relays for 5+amp all circuits with a single
>relay.
I don't like putting the least reliable single component
in a system (relay/contactor) in position to be
single point of failure for all the battery bus.
Recommend you use 5A or less fuse for circuits
will run from these small fuses . . . and add
INDIVIDUAL disconnect relays for each item over
that amount. Leave the battery bus integrity
un-compromised by leaving it firmly attached to
the battery.
Bob. . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>Just about completed wings on a RV-7 and need some help. Installing
>landing light, position light, strobes (in fiberglass tips), nav/com
>antenna wiring (RG-400), also a roll servo for the a/p. Should I run all
>the wires through the 3/4 conduit or should some of them be separated from
>the rest? Also on the strobe heads...the whelen strobes say to ground the
>shielding to the power supply but in Bob's manual it says to ground the
>shielding wire to the strobe heads if mounting in plastic tips. What
>about it list? This is my second OBAM and the first to have more advanced
>equipment and need some advice.
Run them all together. Ground landing lights, nav lights and 14v power
leads for strobes locally. If your strobe bases are not grounded by
virtue of their location on non-conductive mounting, try leaving them
floating. If you get strobe pops in received signals, consider "grounding"
them to shields of leadwires that come out from the strobe supply.
Bob . . .
________________________________________________________________________________
From: | Mark Steitle <msteitle(at)mail.utexas.edu> |
Subject: | Capacitive Fuel Gauges |
Bob,
I have a pair of 6 ft. Electronics International tube type capacitive fuel
level probes and would like to build my own fuel level circuit(s) to use
with these senders. I have a Westach 0-5v dual fuel gauge that I would
also like to use. A series of articles were printed in Kitplanes magazine
in mid 2000 describing how to build a CD type circuit
(http://www.rst-engr.com/kitplanes/index.htm), but it used two flat plates
as the sender. Do you know if the "Jim Weir" capacitive fuel level design
should work with these probes. Is there an easy way to determine the
capacitance of these probes?
Thank you for sharing your knowledge and wisdom with the OBAM community.
Mark S.
________________________________________________________________________________
From: | "Alex Peterson" <alexpeterson(at)usjet.net> |
Subject: | battery / alternator switch |
I like the fact that I get 4 horsepower back at
> cruise RPM that the Vacuum pump stole.
>
Four HP?!? That sounds extremely high (or maybe the air compressor
marketing folks at Sears got ahold of it!). Just to put things in
perspective, a 100 amp, 14 volt alternator would take just a bit more
than two horsepower. In the case of the vacuum pump, where would four
horsepower go? If the vacuum pump is truly taking four horses, the
power has to go somewhere, either doing work (spinning gryos) or
dissipating in the form of heat. The gyros' power requirements are
something near zero, so everything else would be heat. Four horses are
about one eighth as much heat as my home furnace puts out (about
10000btu/hr vs 80000btu/hr). I suspect fractional hp is closer.
Alex Peterson
Maple Grove, MN
RV6-A N66AP 436 hours
www.usfamily.net/web/alexpeterson
________________________________________________________________________________
From: | "Dale Martin" <niceez(at)cableone.net> |
Subject: | Re: battery / alternator switch |
Bob asks,
>One thing I found amazing is how many different places I had ground wires
>terminating. I built my own ground bus only because the ones from B&C do
>not appear to be mechanically attached to the brass . . .
How so?
Mine are riveted on and then soldered. It is the type of -push on tabs -two
way, usually found on Terminal blocks (two holes instead of one) to connect
female 1/4" push-on connecters.
I have attached two Jpeg pictures.
- Dale
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: battery / alternator switch
>
> >
> >In the schematic's for the all electric airplane (Z-13) and the Generic
> >Light Aircraft Electrical System (Z-11) both depicts a Battery / Alt
switch
> ># 2-10 - (2 dash 10). However, in the switches, relays and contactors
pages
> >it says switch 2 dash 3 is recommend for the combination Battery
> >Master/alternator-field switching.
> >
> >Which one is correct?
>
> Either one works. A 2-3 combined with a PULLABLE field supply breaker
> in the crowbar ov protection circuit gives the same functionality as
> a 2-10.
>
> It's no big deal to have the alternator ON during cranking . . . so,
> a 2-3 works.
>
> -EITHER- the mid-position on a 2-10 switch -OR- pulling the field
> circuit breaker allows battery only ops for ground maintenance or
turning
> off a mis-behaving alternator in flight. It's not a matter of
CORRECTNESS
> but a matter of PREFERENCE.
>
>
> >BTW, I have just successfully removed all wires from my 28volt IFR LEZ
(with
> >exception of the strobe and nav light wires in the wings) after 18 years
and
> >1,100 + hours of flying. Talk about scary.... This is for a much
simplier
> >electrical system and full panel upgrade. No more vacuum system for me
and
> >no more 28 to 14 inverter. Everything is 28 volt.
>
> Are you going to 14v or staying 28v?
>
> >One thing I found amazing is how many different places I had ground wires
> >terminating. I built my own ground bus only because the ones from B&C do
> >not appear to be mechanically attached to the brass . . .
>
> How so?
>
> >and my two boys needed
> >some practice using the drill press using brass. The total price was
less
> >then twenty bucks with free labor.
>
> Also this system will only be using one alternator. Using one mag and
one
> >E.I is enough engine redundancy with the lone battery for essential bus.
I
> >believe in the good battery theory and checking it twice per year for
acid
> >specific gravity and over all battery condition and replacing it as
needed.
>
> Do you have a vacuum pump pad with nothing mounted on it?
> For $300 and 4 pounds you can have a SECOND engine driven
> power source.
>
> Bob . . .
>
> -----------------------------------------
> ( Experience and common sense cannot be )
> ( replaced with policy and procedures. )
> ( R. L. Nuckolls III )
> -----------------------------------------
>
>
________________________________________________________________________________
From: | "Dale Martin" <niceez(at)cableone.net> |
Subject: | Re: battery / alternator switch |
This time with the pictures..........
Bob asks,
>One thing I found amazing is how many different places I had ground wires
>terminating. I built my own ground bus only because the ones from B&C do
>not appear to be mechanically attached to the brass . . .
How so?
Mine are riveted on and then soldered. It is the type of -push on tabs -two
way, usually found on Terminal blocks (two holes instead of one) to connect
female 1/4" push-on connecters.
I have attached two Jpeg pictures.
- Dale
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: battery / alternator switch
>
> >
> >In the schematic's for the all electric airplane (Z-13) and the Generic
> >Light Aircraft Electrical System (Z-11) both depicts a Battery / Alt
switch
> ># 2-10 - (2 dash 10). However, in the switches, relays and contactors
pages
> >it says switch 2 dash 3 is recommend for the combination Battery
> >Master/alternator-field switching.
> >
> >Which one is correct?
>
> Either one works. A 2-3 combined with a PULLABLE field supply breaker
> in the crowbar ov protection circuit gives the same functionality as
> a 2-10.
>
> It's no big deal to have the alternator ON during cranking . . . so,
> a 2-3 works.
>
> -EITHER- the mid-position on a 2-10 switch -OR- pulling the field
> circuit breaker allows battery only ops for ground maintenance or
turning
> off a mis-behaving alternator in flight. It's not a matter of
CORRECTNESS
> but a matter of PREFERENCE.
>
>
> >BTW, I have just successfully removed all wires from my 28volt IFR LEZ
(with
> >exception of the strobe and nav light wires in the wings) after 18 years
and
> >1,100 + hours of flying. Talk about scary.... This is for a much
simplier
> >electrical system and full panel upgrade. No more vacuum system for me
and
> >no more 28 to 14 inverter. Everything is 28 volt.
>
> Are you going to 14v or staying 28v?
>
> >One thing I found amazing is how many different places I had ground wires
> >terminating. I built my own ground bus only because the ones from B&C do
> >not appear to be mechanically attached to the brass . . .
>
> How so?
>
> >and my two boys needed
> >some practice using the drill press using brass. The total price was
less
> >then twenty bucks with free labor.
>
> Also this system will only be using one alternator. Using one mag and
one
> >E.I is enough engine redundancy with the lone battery for essential bus.
I
> >believe in the good battery theory and checking it twice per year for
acid
> >specific gravity and over all battery condition and replacing it as
needed.
>
> Do you have a vacuum pump pad with nothing mounted on it?
> For $300 and 4 pounds you can have a SECOND engine driven
> power source.
>
> Bob . . .
>
> -----------------------------------------
> ( Experience and common sense cannot be )
> ( replaced with policy and procedures. )
> ( R. L. Nuckolls III )
> -----------------------------------------
>
>
________________________________________________________________________________
From: | "Dale Martin" <niceez(at)cableone.net> |
Subject: | Re: battery / alternator switch |
Alex,
I will find out from the manufacture if I understood them incorrectly.
Dale Martin
Lewiston, ID
LEZ-235
----- Original Message -----
From: "Alex Peterson" <alexpeterson(at)usjet.net>
Subject: RE: AeroElectric-List: battery / alternator switch
>
>
> I like the fact that I get 4 horsepower back at
> > cruise RPM that the Vacuum pump stole.
> >
>
> Four HP?!? That sounds extremely high (or maybe the air compressor
> marketing folks at Sears got ahold of it!). Just to put things in
> perspective, a 100 amp, 14 volt alternator would take just a bit more
> than two horsepower. In the case of the vacuum pump, where would four
> horsepower go? If the vacuum pump is truly taking four horses, the
> power has to go somewhere, either doing work (spinning gryos) or
> dissipating in the form of heat. The gyros' power requirements are
> something near zero, so everything else would be heat. Four horses are
> about one eighth as much heat as my home furnace puts out (about
> 10000btu/hr vs 80000btu/hr). I suspect fractional hp is closer.
>
> Alex Peterson
> Maple Grove, MN
> RV6-A N66AP 436 hours
> www.usfamily.net/web/alexpeterson
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>
>6/29/2003
>
>Hello Bob Nuckolls and Bret Ferrell, I'd like to flog this horse a few more
>lashes.
>
>1) Bob Nuckolls really says the drain wire should be attached at both ends on
>a composite aircraft? But not on a metal aircraft? Why?
>
>2) When one receives the strobe light installation kit from Whelen the cable
>already has two AMP plastic 3 wire connectors attached, one on each end.
>These
>connectors are the ones that plug into the mating 3 wire connectors at the
>strobe light ends. After cutting the cable somewhere in the middle and
>snaking
>those two cut ends through the airframe to the vicinity of the strobe power
>supply one installs the other two (different) appropriate 3 wire connectors
>provided by Whelen and plugs the cables into the power supply.
>
>3) The installation instructions say that the drain wire should be connected
>to the housing / mounting of the power supply. Easy enough to do by leaving
>the drain wire longer when you cut the cable, strip it, and install the 3
>wire
>connectors that plug into the power supply.
>
>4) But out at the strobe light end of the cable where the Whelen installed
>connectors are, Whelen has left no access to the drain wire. I suppose one
>could
>cut back the plastic covering, remove the aluminum shield, attach a short
>wire to the now exposed drain wire, and then attach that short wire to
>some metal
>part of the strobe light housing, but I find this action both puzzling and
>unnecessary.
>
>5) Whelen has thousands of these units in service throughout the skies
>mounted on both metal surfaces and composite wing tips. I am unaware of
>any need to
>go through the additonal effort of connecting the drain wire to the metal
>light housing out at the strobe light end. Can anyone show me different?
My friend, you're stirring requirements into the same
pot with practice and recommendations based on physics
of the best we know how to do.
You are correct that hundreds of thousands of airplanes
have been wired per manufacturer's instructions and are
"successfully" navigating the skies. I can also tell you
that when we installed strobes on the Cessnas in the
60's (per manufacturer's instructions) our pilots complained
of new noises in the systems. We went to a lot of effort
to mitigate them. I use the term "mitigate" because we never did
eliminate the noises. However, I recall that adding shielding
to the clear dome over the strobes and grounding the
base of the strobes to the shield produced noticeable
reduction in noise.
40 years later, the noises that our pilots complained about
then are now considered commonplace and nobody bothers to
honk about them. I don't recall now if Cessna decided
whether or not to pursue noise reduction to levels over and
above that which was supplied or recommended by Whelen.
By the same token, there are a hundred thousand plus airplanes
that don't used single point grounds, still bring b-lead right
to the bus, etc. etc. (although I understand current production
Cessnas now have single point grounds).
The task here is to do a best practical anticipation
of future "problems" while elevating our art with
sound supporting science. There are no requirements . . . if
the way a cookie cutter spam-can performs and it's the technology
a builder embraces, then many things discussed here on the list
will not be of interest.
Suggestions should not be mistaken for requirements. The vast
majority of OBAM aircraft ARE being assembled and wired in the
great tradition of Cessna, Piper, Beech, et. als. and most
of those airplanes will be pronounced "satisfactory" by their
owners . . . many because they don't know what their options
are for vaulting over higher bars with ease.
My personal goal is to improve the ODDS on "satisfactory"
completion of the maximum number of airplanes while improving
on system reliability. We know that certain techniques have value.
Sometimes it's a very tiny benefit and perhaps insignificant in
the final configuration of completed project. But when someone
comes up on the list with a noise problem, it's very helpful
to know if they've implemented all the techniques we've identified
as easy and useful. That clears the table of the ordinary problems
and lets us concentrate on new ones. If he says, "Naw,
wired 'er up per Van's diagrams and the kit he supplied,"
the dragons to be eliminated are more numerous to identify
and potentially more laborious to fix.
Bob . . .
________________________________________________________________________________
Subject: | Re: For Bob, Comment? |
Quite often, the installers of a STC system try to take advantage of what's
already in the aircraft without fully realizing that they may be
circumventing the intent of the aircraft manufacturer. It's amazing that
the FAA and JAA are willing to grant the STC at all!
----------------------------------------------
Original Message
From: "ivorphillips"<ivor(at)ivorphillips.flyer.co.uk>
Subject: Re: AeroElectric-List: For Bob, Comment?
Date: Mon, 9 Feb 2004 15:41:18 -0000
>
>> There is an upcoming program on Public Broadcasting: NOVA: The Deadly
>It deals with an inflight fire caused by electrical arcing.
>>
>Have seen this program a couple of weeks ago, It make you wonder how a
>commercial aircraft can have its wiring set up in such away that the pilots
>were unable to isolate the entertainment system from the main cockpit Bus!
>No breakers tripped to alleviate the problem, just smoke from behind
>panelling,
>
>I find it hard to believe that circuits are shared without proper regards
>too overload wire protection, Its criminal that so many folk lost their
>lives due to a preventable wiring short circuit.
>
>Ivor Phillips
>Europa xs
>
>
http://www.MyOwnEmail.com
Looking for friendships,romance and more?
http://www.MyOwnFriends.com
________________________________________________________________________________
Subject: | Re: ectric-List:Accuator switch |
I'm trying to wire two accuators that let my canopy go up and down. Can
anyone tell me what kind of switch I need to do this and how it is wired? Thanks
in
advance.
Tom Saccio
________________________________________________________________________________
From: | "Dale Martin" <niceez(at)cableone.net> |
Subject: | Re: ectric-List:Accuator switch |
Stepper motors and a control card otta' do it just fine......
----- Original Message -----
From: <TSaccio(at)aol.com>
Subject: Re: AeroElectric-List:Accuator switch
>
> I'm trying to wire two accuators that let my canopy go up and down. Can
> anyone tell me what kind of switch I need to do this and how it is wired?
Thanks in
> advance.
>
> Tom Saccio
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: battery / alternator switch |
>
>Bob asks,
>
> >One thing I found amazing is how many different places I had ground wires
> >terminating. I built my own ground bus only because the ones from B&C do
> >not appear to be mechanically attached to the brass . . .
>
> How so?
>
>Mine are riveted on and then soldered. It is the type of -push on tabs -two
>way, usually found on Terminal blocks (two holes instead of one) to connect
>female 1/4" push-on connecters.
>
>I have attached two Jpeg pictures.
Attachments don't get forwarded through the list
but that's okay. Rivets are fine too but let's take
care lest folks begin to worry about solder as a structural
material. With a tensile strength on the order of 3Kpsi or
better, likelihood of anyone pulling the fast-on tabs from
their B&C fabricated ground bus is very remote.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | battery / alternator switch |
>
>
>
>I like the fact that I get 4 horsepower back at
> > cruise RPM that the Vacuum pump stole.
> >
>
>Four HP?!? That sounds extremely high (or maybe the air compressor
>marketing folks at Sears got ahold of it!). Just to put things in
>perspective, a 100 amp, 14 volt alternator would take just a bit more
>than two horsepower. In the case of the vacuum pump, where would four
>horsepower go? If the vacuum pump is truly taking four horses, the
>power has to go somewhere, either doing work (spinning gryos) or
>dissipating in the form of heat. The gyros' power requirements are
>something near zero, so everything else would be heat. Four horses are
>about one eighth as much heat as my home furnace puts out (about
>10000btu/hr vs 80000btu/hr). I suspect fractional hp is closer.
I think you're right. Wonder if the decimal place didn't get
moved. 0.4 Hp sounds just about right!
Bob . . .
________________________________________________________________________________
From: | "Dale Martin" <niceez(at)cableone.net> |
Subject: | Re: battery / alternator switch |
Seems like Wayne Blackler has one with the tabs coming off in his tool box.
Each to his own I guess.
Dale Martin
Lewiston, ID
LEZ-235
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: battery / alternator switch
>
> >
> >Bob asks,
> >
> > >One thing I found amazing is how many different places I had ground
wires
> > >terminating. I built my own ground bus only because the ones from B&C
do
> > >not appear to be mechanically attached to the brass . . .
> >
> > How so?
> >
> >Mine are riveted on and then soldered. It is the type of -push on
tabs -two
> >way, usually found on Terminal blocks (two holes instead of one) to
connect
> >female 1/4" push-on connecters.
> >
> >I have attached two Jpeg pictures.
>
> Attachments don't get forwarded through the list
> but that's okay. Rivets are fine too but let's take
> care lest folks begin to worry about solder as a structural
> material. With a tensile strength on the order of 3Kpsi or
> better, likelihood of anyone pulling the fast-on tabs from
> their B&C fabricated ground bus is very remote.
>
> Bob . . .
>
>
________________________________________________________________________________
From: | Jerzy Krasinski <krasinski(at)direcway.com> |
Subject: | Re: Capacitive Fuel Gauges |
I messed around with Jim Weir circuit, but finally I gave up and I made
it using a circuit commonly used as a converter changing volmeter into
capacitance meter. Such a circuit is much simpler, it uses a popular
double timer (556?) and an op amp. Capacitance of my 1 yard long probes
made of 1/2 and 1/4 tubes is around 114 pF, which I measured by a
digital multimeter as well as by substitution of the probe by a capacitor.
Unfortunately, making such a system requires some tinkering and
adjusting the circuit to get proper readings. You must also have some
basic electronic instruments.
Jerzy
Mark Steitle wrote:
>
>Bob,
>I have a pair of 6 ft. Electronics International tube type capacitive fuel
>level probes and would like to build my own fuel level circuit(s) to use
>with these senders. I have a Westach 0-5v dual fuel gauge that I would
>also like to use. A series of articles were printed in Kitplanes magazine
>in mid 2000 describing how to build a CD type circuit
>(http://www.rst-engr.com/kitplanes/index.htm), but it used two flat plates
>as the sender. Do you know if the "Jim Weir" capacitive fuel level design
>should work with these probes. Is there an easy way to determine the
>capacitance of these probes?
>
>Thank you for sharing your knowledge and wisdom with the OBAM community.
>Mark S.
>
>
>
>
________________________________________________________________________________
From: | f1rocket(at)telus.net |
Has anyone out there uses the "Advanced Aircraft Electronics High Gail Aircraft
Antenna Systems" available at AS$?
Esspecially the transponder antenna looks interesting.
Regards,
Jeff
________________________________________________________________________________
From: | "hollandm" <hollandm(at)pacbell.net> |
Subject: | Compass shielding |
I'm getting interference between an electric turn coordinator and a compass (about
2 degrees). Before I start moving things around I was wondering if it would
be possible to shield the compass by surrounding it with some copper screening
or the like, sort of mu-metal chamber approach.
Has anyone tried this and if so did it work?
Thanks
________________________________________________________________________________
From: | Kevin Horton <khorton01(at)rogers.com> |
Subject: | LED light bar annunciator panel? |
I'm seriously considering manufacturing a small annunciator panel
from Stanley LED light bars. These are the ones with part numbers
like MU04-2101 sold by Digikey, etc. I am wondering what options I
would have to put legends on the face of the light bars. What looks
good and lasts a long time? I am also looking for ideas on how to
package the resistors, etc needed to limit the current. Does anyone
have any pictures they could point me too?
Thanks,
--
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
________________________________________________________________________________
Subject: | Re: AeroElectric-List Digest: 29 Msgs - 02/09/04 |
Please remove me for your mail list
bfv25(at)aol.com
________________________________________________________________________________
From: | "Bruce Gray" <Bruce(at)glasair.org> |
Subject: | Compass shielding |
If you shield the compass it will no longer be a compass. It has to be
able to sense the magnetic fields.
Bruce
www.glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
hollandm
Subject: AeroElectric-List: Compass shielding
I'm getting interference between an electric turn coordinator and a
compass (about 2 degrees). Before I start moving things around I was
wondering if it would be possible to shield the compass by surrounding
it with some copper screening or the like, sort of mu-metal chamber
approach.
Has anyone tried this and if so did it work?
Thanks
==
==
==
==
________________________________________________________________________________
From: | Mark Steitle <msteitle(at)mail.utexas.edu> |
Subject: | Re: Capacitive Fuel Gauges |
>
>
>I messed around with Jim Weir circuit, but finally I gave up and I made
>it using a circuit commonly used as a converter changing volmeter into
>capacitance meter. Such a circuit is much simpler, it uses a popular
>double timer (556?) and an op amp. Capacitance of my 1 yard long probes
>made of 1/2 and 1/4 tubes is around 114 pF, which I measured by a
>digital multimeter as well as by substitution of the probe by a capacitor.
Jerzy,
So I would guess that my 6 ft. fuel probe, being twice the length of your 3
ft probe, would have roughly twice the capacitance?
Which Jim Weir circuit did you build, early or late version? A friend
built an early version and got it working, but we had mixed results when we
substituted my probe for his aluminum plate capacitor. As a result, I
thought I might try building one of the Rev. 2 circuits. I would have to
search around for someone with a dual-trace scope to help me adjust/tune
the circuit. Nice thing about the Rev. 2 design is the integrated low fuel
warning light & buzzer.
Do you have any pictures of your design? Or, would you be willing to share
the schematic?
Thanks,
Mark S.
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Compass shielding |
>
>If you shield the compass it will no longer be a compass. It has to be
>able to sense the magnetic fields.
>
>Bruce
>www.glasair.org
>
>
>-----Original Message-----
>From: owner-aeroelectric-list-server(at)matronics.com
>[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
>hollandm
>To: aeroelectric-list(at)matronics.com
>Subject: AeroElectric-List: Compass shielding
>
>
>
>
>I'm getting interference between an electric turn coordinator and a
>compass (about 2 degrees). Before I start moving things around I was
>wondering if it would be possible to shield the compass by surrounding
>it with some copper screening or the like, sort of mu-metal chamber
>approach.
>
>Has anyone tried this and if so did it work?
>
>Thanks
Don't shield the victim, shield the antagonist. Cut a strip
of galvanized flashing metal from the lumber yard
so as to wrap around the t/c about 3 times. Secure
in place with tye-wraps, aluminum tape, string, etc.
I believe this has worked for a number of builders.
Let us know how it does for you.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Gary Casey" <glcasey(at)adelphia.net> |
Subject: | RE: Load dump protection |
<>
Load dump protection in autos is still a real thing. There is a "switch"
between the alternator and the battery and it is the battery terminal
itself. The worst case, that is mostly worried about by boat manufacturers,
is a loose connection on the battery terminal that vibrates, repeatedly
opening and closing. The electronics builders for boats find that it has
not been "solved" as you imply, but is almost a normal situation. The usual
scenario is that the boater stores his boat over the winter, then finds the
battery is dead. He removes the battery and charges it for 10 minutes (the
family is waiting) and then puts it in the boat and just pushes the battery
cable on. The loose cable vibrates, the battery is accepting maximum charge
and the voltage transients are incredible - and repeated many times a
second. Also, the battery doesn't have to be disconnected to have a load
dump. Any time a large load is shut off the alternator has to instantly
reduce its output, which it can't do because of the inductance of the field
windings. Of course, having the battery there tames the load dump to a very
manageable amplitude.
Gary Casey
________________________________________________________________________________
From: | "Dale Martin" <niceez(at)cableone.net> |
Subject: | Re: Compass shielding |
mount it 8 to 10 inches from any electrical current.
Dale Martin
Lewiston, ID
LEZ-235
----- Original Message -----
From: "Bruce Gray" <Bruce(at)glasair.org>
Subject: RE: AeroElectric-List: Compass shielding
>
> If you shield the compass it will no longer be a compass. It has to be
> able to sense the magnetic fields.
>
> Bruce
> www.glasair.org
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
> hollandm
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Compass shielding
>
>
>
>
> I'm getting interference between an electric turn coordinator and a
> compass (about 2 degrees). Before I start moving things around I was
> wondering if it would be possible to shield the compass by surrounding
> it with some copper screening or the like, sort of mu-metal chamber
> approach.
>
> Has anyone tried this and if so did it work?
>
> Thanks
>
>
> ==
> ==
> ==
> ==
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Capacitive Fuel Gauges |
>
>
>Bob,
>I have a pair of 6 ft. Electronics International tube type capacitive fuel
>level probes and would like to build my own fuel level circuit(s) to use
>with these senders. I have a Westach 0-5v dual fuel gauge that I would
>also like to use. A series of articles were printed in Kitplanes magazine
>in mid 2000 describing how to build a CD type circuit
>(http://www.rst-engr.com/kitplanes/index.htm), but it used two flat plates
>as the sender. Do you know if the "Jim Weir" capacitive fuel level design
>should work with these probes. Is there an easy way to determine the
>capacitance of these probes?
>
>Thank you for sharing your knowledge and wisdom with the OBAM community.
>Mark S.
The length of your probe is only part of the equation. Jim's
circuitry is designed to work with a specific change in capacitance
from some total to indicate empty to full. E.g., the probe may have
a range of 150 uF empty to 1000 pF full. You might have a coax connecing
the probe to the electronics that adds another 100 pF. So, the electronics
needs adjusting such that empty is 250 pF and full is 1100 pF.
So, if you have a probe you like and a piece of shielded wire
picked to connect probe to electronics, the task is to mate the
electronics to the probe/cable combination. Jim's schematic includes
empty and full adjust pots. What you need to know is how close
the probe you have comes to the one Jim describes. His circuit
CAN be made to work with about ANY probe.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> 02/09/04 |
Subject: | Re: AeroElectric-List Digest: 29 Msgs - |
02/09/04
02/09/04
>
>Please remove me for your mail list
>bfv25(at)aol.com
You need to go to the UN/SUBSCRIBE address cited below
where you can do it yourself.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: battery / alternator switch |
>
>Seems like Wayne Blackler has one with the tabs coming off in his tool box.
>Each to his own I guess.
>
>Dale Martin
>Lewiston, ID
>LEZ-235
Has he done anything about it? If B&C doesn't want it
back, I'd sure like to see it.
Bob . . .
>----- Original Message -----
>From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
>To:
>Subject: Re: AeroElectric-List: battery / alternator switch
>
>
>
> >
>
> > >
> > >Bob asks,
> > >
> > > >One thing I found amazing is how many different places I had ground
>wires
> > > >terminating. I built my own ground bus only because the ones from B&C
>do
> > > >not appear to be mechanically attached to the brass . . .
> > >
> > > How so?
> > >
> > >Mine are riveted on and then soldered. It is the type of -push on
>tabs -two
> > >way, usually found on Terminal blocks (two holes instead of one) to
>connect
> > >female 1/4" push-on connecters.
> > >
> > >I have attached two Jpeg pictures.
> >
> > Attachments don't get forwarded through the list
> > but that's okay. Rivets are fine too but let's take
> > care lest folks begin to worry about solder as a structural
> > material. With a tensile strength on the order of 3Kpsi or
> > better, likelihood of anyone pulling the fast-on tabs from
> > their B&C fabricated ground bus is very remote.
> >
> > Bob . . .
> >
> >
>
>
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: For Bob, Comment? |
><buckaroo_banzai@the-pentagon.com>
>
>Quite often, the installers of a STC system try to take advantage of what's
>already in the aircraft without fully realizing that they may be
>circumventing the intent of the aircraft manufacturer. It's amazing that
>the FAA and JAA are willing to grant the STC at all!
STC's generally cannot be grand-fathered to other airframes.
STC is exactly what the acronym implies . . . SUPPLEMENT
to a TYPE CERTIFICATE. These are not used as plug-n-play
across a range of aircraft.
STC is EXACTLY what those-who-know-more-about-airplanes-than-
we-do like. Treat every installation like it's never been done
before and test the hell out of it. This keeps those who
don't understand what's happening from having to think or
learn anything. It makes sure that some wheels get invented
over and over again. The STC route is relatively low risk
but also expensive because common sense approaches are
neither encouraged or allowed. Everyone is expected to
read and respond to a rule book. Whether or not he/she
understands the system to which the rules are applied
no longer matters.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: battery / alternator switch |
>
>Bob says,
> > Do you have a vacuum pump pad with nothing mounted on it?
> > For $300 and 4 pounds you can have a SECOND engine driven
> > power source.
> >
> > Bob . . .
>
>I think you mean a Third source. (Battery =1, Alt =2, Second Alt = 3)
>I like the fact that I get 4 horsepower back at cruise RPM that the Vacuum
>pump stole.
Yes, third system source but only the second engine-driven power source.
> > Are you going to 14v or staying 28v?
>
>I will keep 28 v due to the wire size I use are smaller and paid for! And
>have a second full size Alternator on the shelf.
>But to your credit I did consider it but..... then would have to change the
>starter, Alt, Nav-Com 1, landing light, strobe power unit and all the bulbs
>not to mention the LR3. Your talking over $2000 bucks and accepting peanuts
>for some of the equipment I have now.
Understand.
>BTW, I have always started the engine with the Alt off.
Doesn't hurt, but with a well maintained RG battery, probably
has no benefit other than to delay onset of alternator activity.
One might argue that the pilot is watching for effects of the
current action . . . getting the engine started usually concentrates
on things like oil pressure. If the alternator comes up immediately
in a bad mood, it's not likely to be observed as soon as if the
pilot gets the engine started first and then turns on the alternator
while watching instrumentation unique to that activity.
>One thing I think is an error IMHO is not using separate Ignition Switches
>either Guarded or Locking toggle switch for magneto's and especially the
>older LSE electronic ignitions. When the LSE E.I. are turned on they fire
>all the plugs at once - Yikes ! May not be a good idea to do this at any
>RPM. If you were to bump on off in-flight and turn it back on... and it
>fired say 65 BTDC..... That would really mess things up. Klaus warned me
>about it.
I've heard a lot of concerns over the years about "accidental"
switch operation. It's an easy thing to hypothesize but equally
easy to arrange the panel to avoid it too. Hmmm . . . at ANY
RPM? What happens when you do ignition system checks by turning
them off and on one at a time to observe operation of each system
independently?
>On the alternator thread .......
>
>If the C/B on the LR3 field wire were pulled (engine running) is the Alt
>able to still send out power just not regulated? If it does, that is not
>good. I was taught without the field there is no power.
No, with an externally regulated alternator, pulling the field
supply breaker shuts the system down completely. This has always
been the architecture of choice . . . but we'll soon figure out
how to apply internally regulated alternators with equal degree
of comfort.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: Battery Charger |
>
>I am looking at buying a float charger for my 24volt spam can. This spam can
>has an always hot battery bus with the the ships clock on it. I was
>concerned about the following marketing statement as to whether it might
>harm the clock. Anyone care to comment?
>
>Thanks,
>Ned
>
> "High-frequency pulse breaks down sulphated crystals that prevent batteries
>from holding a full charge."
This is a battery maintainer combined with a "de-sulfater".
It should be just fine. It won't hurt your clock or anything
else in the airplane.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Subject: | Re: 11153 Santerre |
>Below is the result of your inquiry. It was submitted by
>Kim Santerre (ksanterre(at)aol.com) on Monday, February 9, 2004 at 19:39:38
>
>Monday, February 9, 2004
>
>Kim Santerre
>
>,
>Email: ksanterre(at)aol.com
>Comments/Questions: Hi Bob:
>
>One of our Light Plane Maintenance Readers wants to know why starter and
>other high current solenoids seem to so badly designed. He said upon
>dissassembly it is obvious that only small points of the contact surface
>repeatedly contact and arc and subsequently have earlier failures than
>they should. Are there any sources of really good quality stuff. He has a
>Lancair. Thanks. Kim Santerre
The writer doesn't understand the physics of high
current, intermittent duty contacts. Virtually
EVERY automotive starter contactor uses the low
area very high pressure philosophy for making and
breaking current to the starter. Now, if he's
seeing poor contactor life, it may have to do with
issues outside the design of the contacts themselves.
This is very mature technology with thousands of
this style contactor flying in airplanes and millions
in ground based vehicles. His problems may have more
to do with WHO builds the contactor than with the
basic science that's supposed to make it work.
I will invite you to join us on the AeroElectric List
to continue this and similar discussions. It's useful to
share the information with as many folks as possible.
A further benefit can be realized with membership on
the list. There are lots of technically capable folks
on the list who can offer suggestions too. You can
join at . . .
http://www.matronics.com/subscribe/
Thanks!
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
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________________________________________________________________________________
From: | Dave Morris <dave(at)davemorris.com> |
Subject: | Re: LED light bar annunciator panel? |
You can have an entire annunciator panel built for you by Aircraft
Simulators.com
Take a look at this: http://www.aircraftsimulators.com/F16caution.html
They can furnish just the panel or also the LEDs and wiring.
January 28, 2004 - February 10, 2004
AeroElectric-Archive.digest.vol-cw