AeroElectric-Archive.digest.vol-hu
April 22, 2008 - May 12, 2008
switch is open. If I don't have power to the main bus, there is no power to
the e-bus unless the alt. feed relay is closed, but the only way for the alt.
feed relay to close is for there to be power to the e-bus.
Shouldn't the alt. feed relay magnet positive terminal come from the BATTERY bus
and then go to the switched ground, or be switched power to that positive terminal
and then go to ground?
Unless I am totally missing something...
George
Tucson, AZ
RV-7
--------
George Jenson -
Tucson, AZ - RV-7 Standard Build
Empennage Completed 1/06
Wings Completed 11/06
Fuselage in Progress
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=178477#178477
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Brownout Battery System P.S. |
On Tue, Apr 22, 2008 at 6:54 AM, Robert L. Nuckolls, III <
nuckolls.bob(at)cox.net> wrote:
> ...
> Take a peek at this drawing I did last night:
>
>
> http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z13-8A(BrownOutBattery).pdf
>
> Here I've suggested that you dump the #2 fat battery and
> the fat contactors associated with #2 master and crossfeed.
> Install a much smaller (7.2 AH, 5.5# 0.04 ohm) "brownout
> battery" and a pair of cube power relays wired such that
> the e-bus is supported ONLY by the brownout battery during
> engine cranking and only while the main bus is loaded so
> heavily that it cannot keep the EFIS from resetting.
>
> This same technique could be added to any single battery
> system (or even Z-14 where you wanted to use both batteries
> for cranking). This modification to Z-13 does not burden the
> SD-8 with supporting fat contactors that are never expected
> to carry cranking currents . . . hence may be ably replaced
> with smaller, plastic relays.
>
> P.S. Here's an exemplar battery that seems well suited to
> this task:
>
> http://aeroelectric.com/Mfgr_Data/Batteries/Panasonic/LC-R127R2P.pdf
>
Bob,
I like the idea of using the starter switch to trigger brown out protection.
Although my AFS EFIS's aren't subject to the dropout (they will go to their
internal backup battery automagically if needed) I'm thinking of using the
AUX battery mgmt. module scheme, which includes manual switching to bring
the AUX battery back online to extend E-bus life. Presumably, it won't be
hard to parallel the starter switch with the AUX battery mgmt. manual switch
to combine the functionality.
Also, FWIW, B&C has a similar battery (BC102-1) that is listed as 0.45
pounds lighter than the Panasonic.
Ron
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Brownout Battery System P.S. |
>
>Bob,
>
>I like the new drawing but help me out in understanding how the E-Bus
>alternate feed relay gets energized and thus energizes the e-bus in the
>event the master switch is open.
>
>If I don't have power to the main bus, there is no power to the e-bus
>unless the alt. feed relay is closed, but the only way for the alt. feed
>relay to close is for there to be power to the e-bus.
>
>Shouldn't the alt. feed relay magnet positive terminal come from the
>BATTERY bus and then go to the switched ground, or be switched power to
>that positive terminal and then go to ground.
>
>Unless I am totally missing something...
Good eye! Thank you. I've published revision B
to correct the error at:
http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z13-8B(BrownOutBattery).pdf
Bob . . .
________________________________________________________________________________
| From: | "John McMahon" <blackoaks(at)gmail.com> |
| Subject: | Re: Rear Mounted Batteries - more questions |
Bob, Very interesting discussion....
We are (were) planning on using Z19RB architecture. Granted, that requires
2 full size batteries (17- 20 AH) which we feel would provide sufficient
backup power in the event of alternator failure, redundant power sources for
the dual fuel pump and ignition required for the 20b Mazda rotory engine and
avoids the added expense and complication of the extra alternator. To
insure good batteries one would be replaced each year.
Our thought was the two batteries would provide adequate power even during
starts to prevent brownouts and a minimum of one and a half hours battery
power (with load shedding of course) in the event of an alternator failure.
We have not tested this battery endurance yet as the panel is not finished.
The brownout relay got me thinking about Z13/8 again....
Any thoughts????
On Tue, Apr 22, 2008 at 6:49 AM, Robert L. Nuckolls, III <
nuckolls.bob(at)cox.net> wrote:
> nuckolls.bob(at)cox.net>
>
>
>
--
John McMahon
Lancair Super ES, S/N 170, N9637M (Reserved)
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Brownout Battery System P.S. |
>On Tue, Apr 22, 2008 at 6:54 AM, Robert L. Nuckolls, III
><nuckolls.bob(at)cox.net> wrote:
>>...
>>
>> Take a peek at this drawing I did last night:
>>
>><http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z13-8A%28BrownOutBattery%29.pdf>http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z13-8A(BrownOutBattery).pdf
>>
>> Here I've suggested that you dump the #2 fat battery and
>> the fat contactors associated with #2 master and crossfeed.
>> Install a much smaller (7.2 AH, 5.5# 0.04 ohm) "brownout
>> battery" and a pair of cube power relays wired such that
>> the e-bus is supported ONLY by the brownout battery during
>> engine cranking and only while the main bus is loaded so
>> heavily that it cannot keep the EFIS from resetting.
>>
>> This same technique could be added to any single battery
>> system (or even Z-14 where you wanted to use both batteries
>> for cranking). This modification to Z-13 does not burden the
>> SD-8 with supporting fat contactors that are never expected
>> to carry cranking currents . . . hence may be ably replaced
>> with smaller, plastic relays.
>>
>> P.S. Here's an exemplar battery that seems well suited to
>> this task:
>>
>><http://aeroelectric.com/Mfgr_Data/Batteries/Panasonic/LC-R127R2P.pdf>http://aeroelectric.com/Mfgr_Data/Batteries/Panasonic/LC-R127R2P.pdf
>
>Bob,
>
>I like the idea of using the starter switch to trigger brown out protection.
>
>Although my AFS EFIS's aren't subject to the dropout (they will go to
>their internal backup battery automagically if needed) I'm thinking of
>using the AUX battery mgmt. module scheme, which includes manual switching
>to bring the AUX battery back online to extend E-bus life. Presumably, it
>won't be hard to parallel the starter switch with the AUX battery mgmt.
>manual switch to combine the functionality.
? if your EFIS is already brown-out proof, what's the
task for an aux battery?
>Also, FWIW, B&C has a similar battery (BC102-1) that is listed as 0.45
>pounds lighter than the Panasonic.
Yeah, there's a bunch of possibilities. I'm still pondering
a DIY project or perhaps a product for incorporation of some
small capacity (read light weight) energy storage devices
into an automatically managed brown-out battery assembly.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Re: Rear Mounted Batteries - more questions |
| From: | "Glaeser, Dennis A" <dennis.glaeser(at)eds.com> |
I have essentially the Z19RB architecture on my Subaru powered RV-7A.
For starting, I leave the Aux Bat master OFF and turn on the E-Bus which
means the starter uses only the main battery and the aux battery powers
the electronics without brownout. Once started, the Aux master comes on
and the E-bus switch goes off. Works great.
Dennis Glaeser
----------------------------------------------------------------------
From: John McMahon
Bob, Very interesting discussion....
We are (were) planning on using Z19RB architecture. Granted, that
requires
2 full size batteries (17- 20 AH) which we feel would provide sufficient
backup power in the event of alternator failure, redundant power sources
for
the dual fuel pump and ignition required for the 20b Mazda rotory engine
and
avoids the added expense and complication of the extra alternator. To
insure good batteries one would be replaced each year.
Our thought was the two batteries would provide adequate power even
during
starts to prevent brownouts and a minimum of one and a half hours
battery
power (with load shedding of course) in the event of an alternator
failure.
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Brownout Battery System P.S. |
>
>
> ? if your EFIS is already brown-out proof, what's the
> task for an aux battery?
If I do add an AUX battery, it would be for extended E-bus run time. I
wouldn't add AUX battery weight for brown out protection alone, unless there
was something else....
Wait! It would also keep my IIRG (Intergalactic Ionic Ray Gun) from
rebooting! Perfect! :-)
Ron
________________________________________________________________________________
| From: | "William Gill" <wgill10(at)comcast.net> |
| Subject: | Encoding Altimeter |
Yep...there are a lot of inconsistencies among FSDO folks. There is an
FAA inspector that monitors this site and he stated that the Dynon did
not need to be TSO'd, but simply meet the altitude testing at the
avionics shop to be legal (I'm surprised he has not yet chimed in --
check the archives). That's good enough for me. Also, a local KC FSDO
inspector called the individual on this site and he too now agrees that
the tested Dynon is legal. I'm not trying to argue, but there are
thousands flying with the Dynon encoder and the FAA folks I have queried
stated that the Dynon IS legal. I am also aware that some areas of the
country have met with resistance from avionics shops as well as their
local FAA folks. What gives?
Best regards,
Bill
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
bakerocb(at)cox.net
Sent: Tuesday, April 22, 2008 8:24 AM
wgill10(at)comcast.net
Subject: AeroElectric-List: Encoding Altimeter
4/22/2008
Hello Bill, Thanks for your input. You wrote:
1) "OR...you could buy a Dynon ........."
Since the Dynon units do not contain a TSO'd altitude encoder operating
the
Dynon unit alone to feed a transponder in flight would presently leave
one
in violation of FAR Sec 91.217 (as interpreted by FAA HQ). There are two
ways to approach this condition:
A) Purchase and install a separate TSO'd altitude encoder and use that
encoder to feed the aircraft's transponder.
B) Decide that violation of 91.217 is an acceptable risk and feed the
transponder from the non TSO'd altitude encoder contained in the Dynon
unit.
2) ".....and save even more during the IFR recertification check."
My local avionics shop charges a flat fee for the FAR Sections 91.411
and
91.413 required testing. This fee has been the same no matter whether I
do
the labor of removing and reinstalling the altimeter and TSO'd altitude
encoder, for bench testing and any adjustments needed prior to the
airplane
side testing, or they do that labor. (By the way, four years ago that
flat
fee was $150, now it is $300.)
3) "........the avionics shops actually prefer the Dynon due to their
accuracy and simplicity."
I hope that the avionics shops continue this practice without any regard
for
what FAR Sec 91.217 says.
4) ".......the avionics shops actually prefer the Dynon due to their
accuracy and simplicity."
I wonder about the complexity of removing and reinstalling an EFIS from
the
airplane compared to the complexity of removing and reinstalling an
altimeter and separate TSO'd altitude encoder should any bench testing
and
adjusting be needed.
A) Maybe EFIS removal and reinstallation is no big deal, but I envision
a
bunch of connections, particularly if it is the type of EFIS that also
includes displaying engine performance parameters.
B) Maybe the EFIS's have no means of local avionics shop adjustment.
C) Maybe the EFIS's would never need adjustment.
D) What has been the experience of EFIS operators that have actually
been
through FAR 91.411 and 91.413 checks, as appropriate, after flying for
at
least two years?
Would any EFIS owners and operators care to comment on these points?.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
---------------------------------------------------
From: "William Gill" <wgill10(at)comcast.net>
Subject: RE: Avionics-List: Encoding Altimeter
OR...you could buy a Dynon and save even more during the IFR
recertification check. In fact, the avionics shops actually prefer the
Dynon due to their accuracy and simplicity.
Bill
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Encoding Altimeter |
Good Evening Bill,
Nothing new here except another data point!
Our granddaughter just finished her Texas Star home built kit and had the
altimeter, transponder and altitude for the 430W certified by a local shop from
the area near Sulphur Springs, Texas. He had no compulsion about using the
Dynon and her airplane is now OK for IFR flight as per the requirements as
listed on the appropriate paperwork.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
Do Not Archive
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/22/2008 8:40:49 P.M. Central Daylight Time,
wgill10(at)comcast.net writes:
Yep...there are a lot of inconsistencies among FSDO folks. There is an
FAA inspector that monitors this site and he stated that the Dynon did
not need to be TSO'd, but simply meet the altitude testing at the
avionics shop to be legal (I'm surprised he has not yet chimed in --
check the archives). That's good enough for me. Also, a local KC FSDO
inspector called the individual on this site and he too now agrees that
the tested Dynon is legal. I'm not trying to argue, but there are
thousands flying with the Dynon encoder and the FAA folks I have queried
stated that the Dynon IS legal. I am also aware that some areas of the
country have met with resistance from avionics shops as well as their
local FAA folks. What gives?
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| Subject: | ELT Antenna for Fiberglass aircraft |
Thanks for the feedback. I found two options at
http://www.wingsandwheels.com/page14.htm One option is to attach a
surface mount BNC connector, add a simple ground plane over the top and
stick on a rubber duck. The fancy option is $108.00
Glenn
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Ernest Christley
Sent: Saturday, April 19, 2008 1:06 PM
Subject: Re: AeroElectric-List: ELT Antenna for Fiberglass aircraft
-->
>>
>> Bruce Gray wrote:
>>>
>>>
>>> I could be wrong but I don't think that dipole antennas are around
>>> for 406
>>> MHTZ ELT's yet. They exist for 121.5 ELT's but they will be obsolete
>>> next
>>> year.
>>>
>>
>> You're wrong. Jim Weir's antennae book shows you how to build one
>> that will handle both frequencies.
>>
>> http://ernest.isa-geek.org/Delta/Pictures/ELTantennae.jpg
I owe Bruce and apology. It's not until I read a later response that
*406 MHz* sunk into my thick skull.
ELT's use two frequencies; neither of which is 406MHz. You have to
build the dipole antennae to handle both of the frequencies, and that is
what I got caught up on. Not that it would be difficult to build a
406MHz dipole, it would just be shorter, but there is very likely little
to no marketed products at the moment.
My sincerest apologies, Bruce.
--
http://www.ronpaultimeline.com
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Brownout Battery System P.S. |
>> ? if your EFIS is already brown-out proof, what's the
>> task for an aux battery?
>
>If I do add an AUX battery, it would be for extended E-bus run time. I
>wouldn't add AUX battery weight for brown out protection alone, unless
>there was something else....
>
>Wait! It would also keep my IIRG (Intergalactic Ionic Ray Gun) from
>rebooting! Perfect! :-)
If you have an SD-8 in addition to the ship's main alternator,
then you essentially enjoy unlimited e-bus endurance irrespective
of the capacity of the ship's battery.
Z-13 lets you run a battery until it doesn't crank the engine
any more. Battery only endurance is not part of the "plan-B".
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Rear Mounted Batteries - more questions |
>Bob, Very interesting discussion....
>
>We are (were) planning on using Z19RB architecture. Granted, that
>requires 2 full size batteries (17- 20 AH) which we feel would provide
>sufficient backup power in the event of alternator failure, redundant
>power sources for the dual fuel pump and ignition required for the 20b
>Mazda rotory engine and avoids the added expense and complication of the
>extra alternator. To insure good batteries one would be replaced each year.
>
>Our thought was the two batteries would provide adequate power even during
>starts to prevent brownouts and a minimum of one and a half hours battery
>power (with load shedding of course) in the event of an alternator failure.
That's consistent with the processes by which Z-19 was crafted.
Dual alternators is simply not a practical option for many
of the automotive conversions.
>We have not tested this battery endurance yet as the panel is not finished.
You should be able to predict e-bus performance. The
Discharge curves for various battery products are generally
available from the manufacturer. Just keep in mind that
the useful capacity is not consistent with variable loads.
The higher the load, the more energy is lost internal to
the battery. In this family of curves . . .
http://www.aeroelectric.com/Pictures/Curves/17AH_12V_Capacity_vs_Load.gif
we see that a new 17 a.h. battery is good for
just over 2 hours with a 4 amp load. So about 1.5
hours when time to toss the battery. On the other
hand, a 10A load is good for about 60 minutes. If
one hour is the new-battery design goal, then end
of service life will be at about 45 minutes.
>The brownout relay got me thinking about Z13/8 again....
>Any thoughts????
It's up to you to decide what goodies are operated
during the alternator out operations and then decide
how much payload you're willing to trade for battery-
only endurance with those loads.
In VMC, your other-than-engine loads can probably
be VERY low thus offering more hours of electrical
support than you have fuel support. A set of pre-flight
tested hand-helds can certainly be part of your plan-B
equation.
Being limited to two batteries, one alternator and
a couple of hand-helds doesn't need to present a
worrisome situation.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Brownout Battery System P.S. |
>
> If you have an SD-8 in addition to the ship's main alternator,
> then you essentially enjoy unlimited e-bus endurance irrespective
> of the capacity of the ship's battery.
>
> Z-13 lets you run a battery until it doesn't crank the engine
> any more. Battery only endurance is not part of the "plan-B".
>
> Bob . . .
>
Understood. Per other thread, I do have an SD-20S for backup ALT, so the
plan C,D,E... AUX battery addition here is not compelling, as you suggest.
However, if I do have to go to the E-bus, perhaps due to a stuck starter,
requiring shutdown of the main contactor even with an alternator still
available, then battery endurance may be an issue, even if not a worry.
Other than that, I might want independent capacity for ground ops (light,
audio, radios, gizmos...) in the boonies with this mini bush plane. Those
are probably the only things that would lead me to commit 6 lbs. (+/-) to an
AUX battery system.
Ron
________________________________________________________________________________
| From: | <gmcjetpilot(at)yahoo.com> |
| Subject: | Lightspeed III & DPS smart Tach, signal issue help? |
Does any one have experience getting a DSP smart tach to work with a LS Plasma
III?
I am helping a guy out with his new Lightspeed III ignition. My analysis the
LS signal is not compatible in stock form to drive the DPS tach.
He wants to use his DPS smart tach (they are out of business BTW). Here is the
issue.
The new ignition LS Plasma III has a tach signal of a square tooth wave from
0 volt to +10 volts amplitude with a duration of 1.5ms. It fires two times per
revolution. OK its a hall effect signal a digital OFF/ON.
Here is the issue, the tach was triggered with a sensor in the access hole of
a magneto. It detected the internal rotating magnet in the magneto. Unlike a
typical magnetic inductive signal (alternating) it states in the installation
manual, voltage sits at a constant +5 volts and when the magnet passes the sensor,
the voltage momentary drops to 0.70 volts. How it looks on a scope I don't
know, probably rounded or spike.
I need to go from the LS's positive square wave signal to a volt drop signal
that is not so square wave, basically inverting the wave.
Is there some easy circuit off the top of your head to convert these two wave
forms, condition the signal? I'm thinking an Op amp, diode and a cap and R or
two.
I'm drawing a blank. The DSP tach does have selection of pulse per rotation.
Taking the tach apart to mod it is not on the table (yet). Access to the schematics
is not likely. May be it is time he bought a new tach?
Thanks George
---------------------------------
Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Lightspeed III & DPS smart Tach, signal issue help? |
>Does any one have experience getting a
>DSP smart tach to work with a LS Plasma III?
>
>I am helping a guy out with his new Lightspeed III ignition. My analysis
>the LS signal is not compatible in stock form to drive the DPS tach.
>
>He wants to use his DPS smart tach (they are out of business BTW). Here is
>the issue.
>
>The new ignition LS Plasma III has a tach signal of a square tooth wave
>from 0 volt to +10 volts amplitude with a duration of 1.5ms. It fires two
>times per revolution. OK its a hall effect signal a digital OFF/ON.
>
>Here is the issue, the tach was triggered with a sensor in the access hole
>of a magneto. It detected the internal rotating magnet in the magneto.
>Unlike a typical magnetic inductive signal (alternating) it states in the
>installation manual, voltage sits at a constant +5 volts and when the
>magnet passes the sensor, the voltage momentary drops to 0.70 volts. How
>it looks on a scope I don't know, probably rounded or spike.
>
>I need to go from the LS's positive square wave signal to a volt drop
>signal that is not so square wave, basically inverting the wave.
Was the original DSP sensor a two-wire or three-wire device?
I've seen through-the-housing aircraft magneto tach sensors
in both formats. The three wire devices are always hall effect
sensors that output a digital friendly, square waveform. If
it was a two-wire device, then it's probably a variable reluctance
sensor . . . a coil of wire wound on a central bias magnet.
The the output from these devices is a digitally unfriendly,
one-cycle per event ground referenced waveform not unlike that
illustrated in Figure 2 of this document.
http://cache.national.com/ds/LM/LM1815.pdf
Usually, the input circuitry for a device expecting a
variable reluctance input signal are capable of
properly responding to a single pulse having
nicely squared edges. But there may be a DC bias
issue presents an offset issue.
Put a 1K resistor across the input to the tach and
then look at DC voltage on both ends of the
resistor. If there is no obvious DC common mode
voltage, then check resistance of each end of
resistor to ground. Hopefully, one end is tied to
ground. If so, then the OTHER end is your real
signal input lead. If there is a measurable
DC voltage and/or neither end of the sensor input
runs at ground, then there's a possibility that
the tachometer expects a floating signal sensor
with some DC continuity and that unlike the
tach chip described above, needs to be spoofed
into believing that the ground referenced, digital
pulse from LS ignition is a variable reluctance
sensor.
The easiest way to craft an interface box is
on the bench. Set up a signal generator to
emulate the output of the LS ignition.
The 555 timer based r/c servo tester is also
suitable. See page 7 of:
http://www.princeton.edu/~mae412/TEXT/NTRAK2002/292-302.pdf
. . . except in this case, you want to vary
the period of the timing pulses (Adjust R3 in
diagram) as opposed to adjusting pulse width
(R2).
>
>Is there some easy circuit off the top of your head to convert these two
>wave forms, condition the signal? I'm thinking an Op amp, diode and a cap
>and R or two.
If the DSP tach expects a dc-continuity through
a sensor with floating ground, you might experiment
with transformer coupling a buffered version
of the LS tach signal. Something like the top sketch
at . . .
http://www.aeroelectric.com/_temp/LS-DSP_Interface.pdf
. . . offers a foundation for a working solution.
If all it needs is an inverter, then the lower
sketch is a starting point.
>
>I'm drawing a blank. The DSP tach does have selection of pulse per
>rotation. Taking the tach apart to mod it is not on the table (yet).
>Access to the schematics is not likely. May be it is time he bought a new tach?
That is probably the least expensive in terms of
$time$. Even after you solve the electronic problem,
there are issues of packaging, installation and
the specter of unanticipated future issues with respect
to EMC, etc.
It's up to all the participants involved to put
value on their $time$ and to assess return on
investment.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Brownout Battery System P.S. |
>> If you have an SD-8 in addition to the ship's main alternator,
>> then you essentially enjoy unlimited e-bus endurance irrespective
>> of the capacity of the ship's battery.
>>
>> Z-13 lets you run a battery until it doesn't crank the engine
>> any more. Battery only endurance is not part of the "plan-B".
>>
>> Bob . . .
>
>Understood. Per other thread, I do have an SD-20S for backup ALT, so the
>plan C,D,E... AUX battery addition here is not compelling, as you suggest.
>
>However, if I do have to go to the E-bus, perhaps due to a stuck starter,
??? how do you get a stuck starter contactor in flight?
> . . .requiring shutdown of the main contactor even with an alternator
> still available, then battery endurance may be an issue, even if not a
> worry. Other than that, I might want independent capacity for ground ops
> (light, audio, radios, gizmos...) in the boonies with this mini bush
> plane. Those are probably the only things that would lead me to commit 6
> lbs. (+/-) to an AUX battery system.
Agreed.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | ELT Antenna for Fiberglass aircraft |
>
>Thanks for the feedback. I found two options at
>http://www.wingsandwheels.com/page14.htm One option is to attach a
>surface mount BNC connector, add a simple ground plane over the top and
>stick on a rubber duck. The fancy option is $108.00
>
>Glenn
A rubber duck for VHF hand held is optimized for
VHF and has no specified/controlled performance at
406 Mhz. One can only guess at the Artex ELT product
but one would like to believe that a qualified ELT
product includes a multi-frequency antenna.
If you're willing to go the VHF comm antenna route,
then consider the Morris loop described at:
http://aeroelectric.com/articles/Morris_Com_Loop_Antenna.pdf
This will out-perform a 125 Mhz optimized rubber duck
at all frequencies of interest for ELT performance.
Bob . . .
________________________________________________________________________________
| From: | "Bill Denton" <bdenton(at)bdenton.com> |
| Subject: | ELT Antenna for Fiberglass aircraft |
JFTR: The Artex 406mHz ELT TSO requires the use of one of the Artex
antennas.
You might want to keep this in mind before deviating...
Thanks!
Bill Denton
bdenton(at)bdenton.com
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Wednesday, April 23, 2008 8:48 AM
Subject: RE: AeroElectric-List: ELT Antenna for Fiberglass aircraft
>
>Thanks for the feedback. I found two options at
>http://www.wingsandwheels.com/page14.htm One option is to attach a
>surface mount BNC connector, add a simple ground plane over the top and
>stick on a rubber duck. The fancy option is $108.00
>
>Glenn
A rubber duck for VHF hand held is optimized for
VHF and has no specified/controlled performance at
406 Mhz. One can only guess at the Artex ELT product
but one would like to believe that a qualified ELT
product includes a multi-frequency antenna.
If you're willing to go the VHF comm antenna route,
then consider the Morris loop described at:
http://aeroelectric.com/articles/Morris_Com_Loop_Antenna.pdf
This will out-perform a 125 Mhz optimized rubber duck
at all frequencies of interest for ELT performance.
Bob . . .
________________________________________________________________________________
| From: | "Terry Frazier" <fraziernv(at)earthlink.net> |
| Subject: | Re: Brownout Battery System P.S. |
I'm building a 7A with a somewhat modified z19 system. I'll probably use
both 16ah batteries to start, so I am concerned about EFIS (GRT) brownout
too. I've been thinking for some time that the brownout situation might be
solved with a large capacitor wired to feed the EFIS for a short time. I
see very large capacitors (1 Farad for $40) advertised for the car stereo
crowd. I think they use them to limit voltage variations while they are
trying to blow out everyone's eardrums...
What do you think?
Terry
________________________________________________________________________________
| Subject: | A36 wiring diagram |
Does anyone have a wiring diagram for an A36 Bonanza? I've got a FWF from a
1997 A36 and am putting it in my Navion (STC for the engine/prop). It comes
with the 5 engine instruments which all have unique stamped numbers on their
harnesses. They were cut when removed and I need to identify those numbers.
Aside from reconnecting them to the sensors I need to add them to my wiring
diagram. I only need the page or pages that deal with the engine instruments
(MP, RPM, Oil Temp/Press, Fuel Flow & EGT/CHT). Any help is appreciated.
Regards,
Greg Young
________________________________________________________________________________
| From: | Nick Gautier <Thomas.N.Gautier(at)jpl.nasa.gov> |
| Subject: | Re: Brownout Battery System P.S. |
Bob,
I looked at your Z13-8B(BrownOutBattery).pdf. It seems to me
that the only reason not to hook a battery like the Panasonic LC-R127R2P
directly to the endurance bus and do away with the brown-out
battery relay, alternate feed relay and the E-bus alternate feed switch
is that the battery won't charge properly through the diode
connecting the main bus to the endurance bus. However, what if you use
a shottky diode for the main bus/endurance bus connection?
The power shottky on the Perihelion Design site apparently has about
0.2v forward drop. The Panasonic spec sheet you pointed to says, if I
read it right, that the battery needs 13.6-13.8 v terminal voltage to trickle
charge. So the brown-out battery should stay charged OK if the alternator
is regulated to supply more than 14.0 v, which I understand it has to do to
keep the main battery charged.
Am I missing something simple (or subtle) that makes this not work or
a bad idea?
Nick Gautier
RV-10, in progress
> I've been pondering this discussion for the last day or so and
> I wasn't pleased with the lack of elegance. It seemed that your
> design goals were not well served with the present suite of hardware
> (too heavy).
~snip~
> So what's a reasonable middle ground? Take a peek at:
>
> Take a peek at this drawing I did last night:
>http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z13-8A(BrownOutBattery).pdf
> Here I've suggested that you dump the #2 fat battery and
> the fat contactors associated with #2 master and crossfeed.
> Install a much smaller (7.2 AH, 5.5# 0.04 ohm) "brownout
> battery" and a pair of cube power relays wired such that
> the e-bus is supported ONLY by the brownout battery during
> engine cranking and only while the main bus is loaded so
> heavily that it cannot keep the EFIS from resetting.
~snip~
> P.S. Here's an exemplar battery that seems well suited to
> this task:
>http://aeroelectric.com/Mfgr_Data/Batteries/Panasonic/LC-R127R2P.pdf
> Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Brownout Battery System P.S. |
>
>
>I'm building a 7A with a somewhat modified z19 system. I'll probably use
>both 16ah batteries to start, so I am concerned about EFIS (GRT) brownout
>too. I've been thinking for some time that the brownout situation might be
>solved with a large capacitor wired to feed the EFIS for a short time. I
>see very large capacitors (1 Farad for $40) advertised for the car stereo
>crowd. I think they use them to limit voltage variations while they are
>trying to blow out everyone's eardrums...
>
>What do you think?
A 1F capacitor impressed with 1A of current flow changes
voltage at 1 volt / second. Okay, supporting an EFIS system
that draws say 5A from brownout works out to this kind
of scenario:
Capacitor charge start point 12.5V
EFIS barfs at say 9V so assume .5 volt of headroom
and we don't want voltage to fall below 9.5 volts
for an allowable delta of 3 volts.
With a 5 volt per second decay on the support capacitor
(5A and 1F) we have 3/5 or 0.6 seconds to get the
supply voltage back above 9.5v + 0.7v (diode
isolation) = 10.2 volts. Probably not an unreasonable
thing to do electrically.
The other consideration is weight and volume of
the installed capacitor and associated switchgear.
A battery is probably smaller and lighter but has
a cost of ownership in maintenance.
Consider this. What's the real downside for cranking
the engine before you start up the EFIS system? The
corollary to that question is what's the hazard to
hardware or operation of the system by having the
EFIS system reboot?
This is an excellent illustration of the gyrations
that system designers go through in sifting all
the combinations of simple-ideas in search of the
elegant solution. You define "elegant" any way
you like.
Now, here's another combination of simple-ideas:
http://www.aeroelectric.com/Pictures/Schematics/Brown-Out_Protection_1.pdf
I built this device to protect a Unisom electronic
ignition system about 10 years ago. It's a simple boost
supply that you put in series with the protected system
that operates only while the engine is cranking. It's
boosts battery-only supply voltage by approximately 3
volts and becomes a passive 0.7 volt constant drop
when the engine is not cranking.
Let's say you're protecting a 5A load again. This
means the power supply is tailored for 15 watts
of load. It can be fabricated in less than 3 cubic
inches of volume and under 5 ounces. Since it's
active only while the engine is cranking, all the
DO-160 issues with respect to EMC go away.
Perhaps this fits the definition of elegant solution
for a variety of projects.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: A36 wiring diagram |
>Does anyone have a wiring diagram for an A36 Bonanza? I've got a FWF from
>a 1997 A36 and am putting it in my Navion (STC for the engine/prop). It
>comes with the 5 engine instruments which all have unique stamped numbers
>on their harnesses. They were cut when removed and I need to identify
>those numbers. Aside from reconnecting them to the sensors I need to add
>them to my wiring diagram. I only need the page or pages that deal with
>the engine instruments (MP, RPM, Oil Temp/Press, Fuel Flow & EGT/CHT). Any
>help is appreciated.
>
I can probably get them. They're on the Hawker-Beech
dealer data website. In fact, I'm not sure I don't
have the a36 drawings in a project file I compiled during
a development program some years ago. Let me thrash around
and see what I can find.
Bob . . .
________________________________________________________________________________
| From: | CardinalNSB(at)aol.com |
| Subject: | Re: AeroElectric-List Digest: 25 Msgs - 04/22/08 |
...B) Decide that violation of 91.217 is an acceptable risk and feed the
transponder from the non TSO'd altitude encoder contained in the Dynon
unit.....
Well, how does one decide that the real physical risk of a non-TSO's over a
TSO product is acceptable? How could I, even if I understood all the tso
testing and general electronics manufacturing business, make fact based
assessments as to the reliability of any electronic equipment unless I had a lab
and
testing lab essentially?
I'm sure there is anecdotal evidence of the Dynon's reliability. And I
understand we might want to behave in ways that mitigate against a single failure
ruining my day. But in a pinch, what tells me to trust one instrument over
another in a serious moment, especially when the error is not so great to be
obvious? Skip
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: AeroElectric-List Digest: 25 Msgs - 04/22/08 |
Good Evening Skip,
Do you intend to have only the Dynon for altitude information?
I will not be flying IFR without having a standard altimeter for reference,
but that is part of my risk assessment.
Here is my thought trail.
What harm will befall me if the Dynon sends false information to the
transponder?
Or, --- What harm will befall me if the Dynon does not send any data to the
transponder?
When I have had a transponder send bad data (From fully certified and TSO'd
equipment by the way) to the FEDs, they have told me about it and asked that
I turn off the altitude function.
So far, that has seemed to be within the acceptable risk that I am willing
to take.
Whadda Ya think?
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/23/2008 4:28:31 P.M. Central Daylight Time,
CardinalNSB(at)aol.com writes:
...B) Decide that violation of 91.217 is an acceptable risk and feed the
transponder from the non TSO'd altitude encoder contained in the Dynon
unit.....
Well, how does one decide that the real physical risk of a non-TSO's over a
TSO product is acceptable? How could I, even if I understood all the tso
testing and general electronics manufacturing business, make fact based
assessments as to the reliability of any electronic equipment unless I had a lab
and
testing lab essentially?
I'm sure there is anecdotal evidence of the Dynon's reliability. And I
understand we might want to behave in ways that mitigate against a single failure
ruining my day. But in a pinch, what tells me to trust one instrument over
another in a serious moment, especially when the error is not so great to be
obvious? Skip
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
| Subject: | Re: AeroElectric-List Digest: 25 Msgs - 04/22/08 |
works for me...But so far my Dynon has been flawless...
Frank RV7a IFR
________________________________
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectr
ic-list-server(at)matronics.com] On Behalf Of BobsV35B(at)aol.com
Sent: Wednesday, April 23, 2008 4:01 PM
Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 25 Msgs - 04/
22/08
Good Evening Skip,
Do you intend to have only the Dynon for altitude information?
I will not be flying IFR without having a standard altimeter for reference,
but that is part of my risk assessment.
Here is my thought trail.
What harm will befall me if the Dynon sends false information to the transp
onder?
Or, --- What harm will befall me if the Dynon does not send any data to the
transponder?
When I have had a transponder send bad data (From fully certified and TSO'd
equipment by the way) to the FEDs, they have told me about it and asked th
at I turn off the altitude function.
So far, that has seemed to be within the acceptable risk that I am willing
to take.
Whadda Ya think?
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/23/2008 4:28:31 P.M. Central Daylight Time, CardinalNS
B(at)aol.com writes:
...B) Decide that violation of 91.217 is an acceptable risk and feed the
transponder from the non TSO'd altitude encoder contained in the Dynon unit
.....
Well, how does one decide that the real physical risk of a non-TSO's over a
TSO product is acceptable? How could I, even if I understood all the tso
testing and general electronics manufacturing business, make fact based ass
essments as to the reliability of any electronic equipment unless I had a l
ab and testing lab essentially?
I'm sure there is anecdotal evidence of the Dynon's reliability. And I und
erstand we might want to behave in ways that mitigate against a single fail
ure ruining my day. But in a pinch, what tells me to trust one instrument
over another in a serious moment, especially when the error is not so great
to be obvious? Skip
________________________________
Need a new ride? Check out the largest site for U.S. used car listings at A
OL Autos<http://autos.aol.com/used?NCID=aolcmp00300000002851>.
________________________________________________________________________________
| Subject: | Re: AeroElectric-List Digest: 25 Msgs - 04/22/08 |
| From: | "Matt Prather" <mprather(at)spro.net> |
Right on, Bob..
I would argue that using the Dynon as the Txp encoder lowers overall risk
as compared to having a standalone encoder. Even if the baro sensor in
the Dynon isn't "as good" as the one from AmeriKing (yeah right..). For
one thing, should the Dynon display provide the primary altitude
information to the pilot, if the altitude readout gets weird, the pilot
will know it fairly quickly under most circumstances. If the airplane has
a backup Kohlsmann.
With the vast majority of standalone encoders feeding their output only to
the Txp, the pilot won't know there's a problem unless ATC complains.
Many VFR pilots never talk to ATC, but often their airplanes are equipped
and hence must operate transponders squawking altitude. If the encoder
fails the day after they leave the radio shop, they'll fly two years
reporting the wrong altitude to ATC and TCAS boxes before the problem is
detected.. It happens, and apparently it's not generally terribly
hazardous.
My preference would be a Dynon (or something similar) driving the Txp and
a GPS unit that displays altitude data. I realize they won't line up very
closely due to temperature issues, but I'm not worried about being +/-300
ft.
Another idea (which is likely not new/unique) is to have the EFIS compare
the GPS altitude against baro altitude (calculating/compensating for
measured temperature) and flash a warning any time there's a noteworthy
discrepancy. Easy to implement, and will help keep me from forgetting to
enter the proper baro setting into the EFIS (either at flight start or
after having flown several hours - through weather systems). And it
should catch rare cases where the EFIS's baro sensor has gone south -
keeping the Txp data clean.
Regards,
Matt-
> Good Evening Skip,
>
>
> Do you intend to have only the Dynon for altitude information?
>
>
> I will not be flying IFR without having a standard altimeter for
> reference,
> but that is part of my risk assessment.
>
> Here is my thought trail.
>
>
> What harm will befall me if the Dynon sends false information to the
> transponder?
>
> Or, --- What harm will befall me if the Dynon does not send any data to
> the
> transponder?
>
> When I have had a transponder send bad data (From fully certified and
> TSO'd
> equipment by the way) to the FEDs, they have told me about it and asked
> that
> I turn off the altitude function.
>
> So far, that has seemed to be within the acceptable risk that I am willing
> to take.
>
> Whadda Ya think?
>
> Happy Skies,
>
> Old Bob
> AKA
> Bob Siegfried
> Ancient Aviator
> 628 West 86th Street
> Downers Grove, IL 60516
> 630 985-8502
> Stearman N3977A
> Brookeridge Air Park LL22
>
>
> In a message dated 4/23/2008 4:28:31 P.M. Central Daylight Time,
> CardinalNSB(at)aol.com writes:
>
>
> ...B) Decide that violation of 91.217 is an acceptable risk and feed the
> transponder from the non TSO'd altitude encoder contained in the Dynon
> unit.....
>
>
> Well, how does one decide that the real physical risk of a non-TSO's over
> a
> TSO product is acceptable? How could I, even if I understood all the tso
> testing and general electronics manufacturing business, make fact based
> assessments as to the reliability of any electronic equipment unless I
> had a lab and
> testing lab essentially?
>
> I'm sure there is anecdotal evidence of the Dynon's reliability. And I
> understand we might want to behave in ways that mitigate against a single
> failure
> ruining my day. But in a pinch, what tells me to trust one instrument
> over
> another in a serious moment, especially when the error is not so great to
> be
> obvious? Skip
>
>
> **************Need a new ride? Check out the largest site for U.S. used
> car
> listings at AOL Autos.
> (http://autos.aol.com/used?NCID=aolcmp00300000002851)
>
________________________________________________________________________________
| From: | "Lee Logan" <leeloganster(at)gmail.com> |
| Subject: | Re: AeroElectric-List Digest: 28 Msgs - 04/21/08 |
Great responses to my inquiry on the utility of a battery bus (or not);
thanks to all who contributed. Confirms my suspicions. I don't believe I
have any "keep alive" requirements and I have a hot wired "pig tail" routed
where I can readily charge the battery and/or power the avionics for
extended periods on the ground, if need be. No dome light in a slider
canopy, etc. etc.
Thanks again for the help...
Lee...
________________________________________________________________________________
| From: | "Bill Bradburry" <bbradburry(at)bellsouth.net> |
| Subject: | Hope someone can point me in the right direction for |
troubleshooting.
I have come upon a problem. My plane is wired per Z-19 with two batteries.
Everything has been working fine. A couple of days ago, I started the
installation of my radios. To do so, I had to lean my panel forward to gain
access to the back.
When I next started the engine, I could hear what sounded like a loose strap
blowing and hitting against the bottom of the plane. I have since found
that this sound is caused by one of the solenoids making a clicking noise.
This sound would go away if I turned the alternator off, but the alternator
was outputting power when it was on. The next day, I found that I could not
get the alternator to output power at all. But.the clicking sound was gone!
I removed both the alternator and voltage regulator and had them checked.
Both are working.Just not on my plane!
I am suspicious that I either have a hot wire loose or a ground has come
off. Does it sound to any of you like this could be the problem?
I will check for that tomorrow, but then I will be completely out of ideas
as to what to try.
Maybe someone can help here?
Bill B
________________________________________________________________________________
| Subject: | ELT Antenna for Fiberglass aircraft |
Thanks Bob et al,
I'll be using 121.5 until someone with a badge walks up to me and says
otherwise. The Morris loop looks like a great option in the < 125 range.
Glenn
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Sent: Wednesday, April 23, 2008 9:48 AM
Subject: RE: AeroElectric-List: ELT Antenna for Fiberglass aircraft
-->
>
>Thanks for the feedback. I found two options at
>http://www.wingsandwheels.com/page14.htm One option is to attach a
>surface mount BNC connector, add a simple ground plane over the top and
>stick on a rubber duck. The fancy option is $108.00
>
>Glenn
A rubber duck for VHF hand held is optimized for
VHF and has no specified/controlled performance at
406 Mhz. One can only guess at the Artex ELT product
but one would like to believe that a qualified ELT
product includes a multi-frequency antenna.
If you're willing to go the VHF comm antenna route,
then consider the Morris loop described at:
http://aeroelectric.com/articles/Morris_Com_Loop_Antenna.pdf
This will out-perform a 125 Mhz optimized rubber duck
at all frequencies of interest for ELT performance.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Brownout Battery System P.S. |
>
>
>Bob,
>
> I looked at your Z13-8B(BrownOutBattery).pdf. It seems to me
>that the only reason not to hook a battery like the Panasonic LC-R127R2P
>directly to the endurance bus and do away with the brown-out
>battery relay, alternate feed relay and the E-bus alternate feed switch
>is that the battery won't charge properly through the diode
>connecting the main bus to the endurance bus. However, what if you use
>a shottky diode for the main bus/endurance bus connection?
You always need the alternate feed relay (or switch). You don't want
to leave the e-bus hot when the airplane is parked. You also need a way
to pre-flight the normal feedpath.
> The power shottky on the Perihelion Design site apparently has about
>0.2v forward drop. The Panasonic spec sheet you pointed to says, if I
>read it right, that the battery needs 13.6-13.8 v terminal voltage to trickle
>charge. So the brown-out battery should stay charged OK if the alternator
>is regulated to supply more than 14.0 v, which I understand it has to do to
>keep the main battery charged.
The Shottky diode is alluring . . . but it needs to
be insulated from ground and perhaps heat-sinked. It's
also probably more expensive than the plastic cube relay.
Having said that, since the brown-out battery is not needed
to bolster capacity and is only expected to carry a load for
tens of milliseonds per flight cycle, then the diode is certainly
an option. Diode isolation would be the architecture of choice for the
capacitor based brown-out technique discussed in the earlier
post.
But in either case, the alternate feedpath switch/relay is
called for.
> Am I missing something simple (or subtle) that makes this not work or
>a bad idea?
Keep in mind that during battery only operations, this same
diode would be in series with a voltage source that is
already depressed below 'normal' bus voltage. What you
propose would probably function at some level. But for the
moment, I'll have to continue to champion hard-closed contacts
of relays and switches as being more efficient and lower cost
of ownership without impacting system reliability.
Now, a Shottky diode in the normal feedpath is certainly
an option. But the "advantage" of lower voltage drop looses
its luster . . . while the alternator is running you have
watts-to-burn. So I'll suggest that the selection of this
diode should include considerations of cost and convenience
in mounting.
Bob . . .
________________________________________________________________________________
| From: | "Bill and Marsha" <docyukon(at)ptcnet.net> |
I just learned that as of yesterday Navaid Devices has closed
their doors. Anyone have any more info?
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Hope someone can point me in the right direction |
for troubleshooting.
> I have come upon a problem. My plane is wired per Z-19 with two
> batteries. Everything has been working fine. A couple of days ago, I
> started the installation of my radios. To do so, I had to lean my panel
> forward to gain access to the back.
>
>When I next started the engine, I could hear what sounded like a loose
>strap blowing and hitting against the bottom of the plane. I have since
>found that this sound is caused by one of the solenoids making a clicking
>noise. This sound would go away if I turned the alternator off, but the
>alternator was outputting power when it was on. The next day, I found
>that I could not get the alternator to output power at all. But&the
>clicking sound was gone!
>
>I removed both the alternator and voltage regulator and had them
>checked. Both are working&Just not on my plane!
>
>I am suspicious that I either have a hot wire loose or a ground has come
>off. Does it sound to any of you like this could be the problem?
>
>I will check for that tomorrow, but then I will be completely out of ideas
>as to what to try.
>
>
>Maybe someone can help here?
You're faced with the classic troubleshooting problem.
There are lots of places where a gross disconnect
can occur to produce the symptoms you cite. Fortunately
it's not an intermittent problem so your aiming at
moving target. Sorry I cannot be more specific.
Bob . . .
________________________________________________________________________________
| From: | John Swartout <jgswartout(at)earthlink.net> |
| Subject: | Mechanical question |
Does anyone have a nice, elegant method for mounting on a flat surface the in-line
automotive-type fuse-holder sold by B&C? It has no built-in mounting tab
or any such thing.
Thanks.
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Mechanical question |
On Thu, Apr 24, 2008 at 4:43 PM, John Swartout
wrote:
> jgswartout(at)earthlink.net>
>
>
> Does anyone have a nice, elegant method for mounting on a flat surface the
> in-line automotive-type fuse-holder sold by B&C? It has no built-in
> mounting tab or any such thing.
>
If you're referring to B&C's "HFB" inline yellow fuse holder, an
MS21919-WDG11 "Adel" clamp works well -- nice and snug --on the one end
where there's space for it.
Ron
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Mechanical question |
On Thu, Apr 24, 2008 at 5:43 PM, Ron Shannon wrote:
> On Thu, Apr 24, 2008 at 4:43 PM, John Swartout
> wrote:
>
>> jgswartout(at)earthlink.net>
>>
>>
>> Does anyone have a nice, elegant method for mounting on a flat surface the
>> in-line automotive-type fuse-holder sold by B&C? It has no built-in
>> mounting tab or any such thing.
>>
>
> If you're referring to B&C's "HFB" inline yellow fuse holder, an
> MS21919-WDG11 "Adel" clamp works well -- nice and snug --on the one end
> where there's space for it.
>
> Ron
>
You're probably referring instead to the black blade-style fuse holder
(IFH-2) though. You can put a black cable "zip" tie around the base (circle
parallel to the wire) attached to a stick-on nylon zip tie holder. The
holder will keep it off the surface a bit which aids access to the fuse. Not
super "elegant", but it works.
Ron
________________________________________________________________________________
| From: | "Jim" <jjewell(at)telus.net> |
| Subject: | Re: Mechanical question |
John,
The Buss fuse holders that I used had recessed holes suitable for number 8
machine screws. The local hardware store aircraft section supplied screws of
correct length.
Jim in Kelowna
----- Original Message -----
From: "John Swartout" <jgswartout(at)earthlink.net>
Sent: Thursday, April 24, 2008 4:43 PM
Subject: AeroElectric-List: Mechanical question
>
>
>
> Does anyone have a nice, elegant method for mounting on a flat surface the
> in-line automotive-type fuse-holder sold by B&C? It has no built-in
> mounting tab or any such thing.
>
> Thanks.
>
>
> --
> Checked by AVG.
> 7:24 AM
>
>
________________________________________________________________________________
| Subject: | Mechanical question |
The simple and elegant solution is to use a dab of epoxy. I will stick
to anything. Position the holder such that you can get the top off to
service the fuse. If you want to buy something take a look at click-bond
products. They have a fastener for everything you could ever want to tie
down in your airplane. Warning - they are not exactly cheap.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jim
Sent: Thursday, April 24, 2008 9:08 PM
Subject: Re: AeroElectric-List: Mechanical question
John,
The Buss fuse holders that I used had recessed holes suitable for number
8
machine screws. The local hardware store aircraft section supplied
screws of
correct length.
Jim in Kelowna
----- Original Message -----
From: "John Swartout" <jgswartout(at)earthlink.net>
Sent: Thursday, April 24, 2008 4:43 PM
Subject: AeroElectric-List: Mechanical question
>
>
>
> Does anyone have a nice, elegant method for mounting on a flat surface
> the
> in-line automotive-type fuse-holder sold by B&C? It has no built-in
> mounting tab or any such thing.
>
> Thanks.
>
>
> --
> Checked by AVG.
> 7:24 AM
>
>
________________________________________________________________________________
| From: | Edward Christian <edchristian(at)knology.net> |
Does someone have a Z-11 diagram with a keyed ACS type switch (Off/L/R/
Start)? Redoing panel and using some old components - I know it is not
optimum.
Ed
________________________________________________________________________________
| From: | Jim Piavis <jpiavis(at)microsoft.com> |
Anyone know the best source for an Artex ELT battery replacement? I need on
e for an ME406.
________________________________________________________________________________
| From: | "Jim McBurney" <jmcburney(at)pobox.com> |
| Subject: | Re: navaid devices |
I just read this post, and put in a call to Navaid Devices. They aren't
answering their telephone, so it may be true. Bummer! I was about to order
their product.
Blue skies and tailwinds
Jim
CH-801
DeltaHawk diesel
Augusta GA
90% done, 90% left
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
>
>
>Does someone have a Z-11 diagram with a keyed ACS type switch (Off/L/R/
>Start)? Redoing panel and using some old components - I know it is not
>optimum.
Figure Z-26 is the adjunct drawing to support the legacy
magneto/start switch. Keep in mind that all the Z-Figures
are intended to suggest architectures. The customization
of wire gauges, fuse/breaker sizes, bus structures,
alternator, starter, and ignition selections make for a
few million different combinations of electrical system
drawings . . . all of which conform to the spirit and
intent of Z-11.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Hope someone can point me in the right direction |
for troubleshooting.
| From: | Dan Morrow <DanFM01(at)butter.toast.net> |
> >When I next started the engine, I could hear what sounded like a loose
> >strap blowing and hitting against the bottom of the plane. I have since
> >found that this sound is caused by one of the solenoids making a clicking
> >noise. This sound would go away if I turned the alternator off, but the
> >alternator was outputting power when it was on. The next day, I found
> >that I could not get the alternator to output power at all. But&the
> >clicking sound was gone!
FYI the clicking sound when starting is a result of low battery voltage.
I've seen this several times in autos. What happens is you turn on the
starter switch which causes the starter solenoid to engage. The starter
comes on line putting humongous load on battery. Battery can't cope and
voltage drops so far that starter solenoid disengages. Starter load is
gone and battery voltage recovers and starter solenoid reengages etc.
The result is a rapid clicking sound.
This can be the result of an old battery or corroded battery cables or
corroded battery terminals or discharged battery or alternator failing
to charge the battery or bad starter or intermittent connections etc.
Basically you just have to check everything.
________________________________________________________________________________
| From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
| Subject: | Hope someone can point me in the right direction |
for troubleshooting.
Depends where the solenoid is of course..Some experimentals use a solenoid to switch
the output of the alternator...If this is the case then its probably the
solenoid has died.
If it is the battery contactor then the rapid turning on and off may have fried
the output diodes of the alternator itself.
I would try connecting the alternator B lead directly to the battery terminal and
see if it wakes up...If not get the alternator checked out.
Assumes there is not an intermittent wiring connection to the alternator as well.
Frank
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Dan Morrow
Sent: Friday, April 25, 2008 9:49 AM
Subject: Re: AeroElectric-List: Hope someone can point me in the right direction
for troubleshooting.
-->
> >When I next started the engine, I could hear what sounded like a
> >loose strap blowing and hitting against the bottom of the plane. I
> >have since found that this sound is caused by one of the solenoids
> >making a clicking noise. This sound would go away if I turned the
> >alternator off, but the alternator was outputting power when it was
> >on. The next day, I found that I could not get the alternator to
> >output power at all. But&the clicking sound was gone!
FYI the clicking sound when starting is a result of low battery voltage.
I've seen this several times in autos. What happens is you turn on the starter
switch which causes the starter solenoid to engage. The starter comes on line
putting humongous load on battery. Battery can't cope and voltage drops so
far that starter solenoid disengages. Starter load is gone and battery voltage
recovers and starter solenoid reengages etc.
The result is a rapid clicking sound.
This can be the result of an old battery or corroded battery cables or corroded
battery terminals or discharged battery or alternator failing to charge the battery
or bad starter or intermittent connections etc.
Basically you just have to check everything.
________________________________________________________________________________
| From: | "Richard Dudley" <rhdudley1(at)bellsouth.net> |
Hi Ed,
The system rejected my attachment in CAD format.
So I am trying again with a DWG format.
Regards,
Richard Dudley
RV-6A flying
----- Original Message -----
From: "Edward Christian" <edchristian(at)knology.net>
Sent: Friday, April 25, 2008 10:53 AM
Subject: AeroElectric-List: Key Switch
>
>
> Does someone have a Z-11 diagram with a keyed ACS type switch (Off/L/R/
> Start)? Redoing panel and using some old components - I know it is not
> optimum.
>
> Ed
>
>
>
________________________________________________________________________________
| From: | Jay Caldwell <caldwelljf(at)sbcglobal.net> |
I am building a CH-801 and am in need of a dual throttle setup so one canm fly
from eithr side given there is a "Y" shaped stick in the center.
I had in mind a "fly by wire" arrangement. If I could connect a servo to the "throttle
door", I could then conect a throttle quadrant with a "pot" connected
to it and actuate the throttle from either side; Pilot with left hand and Co
pilot with right hand.. Using a switch I could assign the servo to the Pilot
or Copilot.
Any ideas?
Jay F. Caldwell
Owner, Caldwell Systems Engineering (CSE), LLC
4181 Tamilynn Court
San Diego, CA 92122
Office email caldwell(at)mswin.net
Voice 858.453.4594
Facsimile 858.452.1560
Work 619.562.0885
Mobile 858.336.0394
Hanger 760-789-2557
________________________________________________________________________________
| From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
No, No and...NO...
This is a really bad idea. This represents a single point of failure which
is always a bad idea on a critical system on an airplane...Especially an el
ectrical one
In other words if any one of half a dozen failures occurs you could very ea
sily die...namely, a fuse blows, faulty wring, servo dies...etc
Don't do it!
Maybe if you have 2 servos and two electrically independant pots then maybe
but really a cable is the way to go...two cables if you have two throttles
.
Would the CH601 dual arrangement work?..I have an RV7 that has two airplane
style cables going to one throttle..works fine...well it will when I insta
ll the second cable..:)
Frank
________________________________
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectr
ic-list-server(at)matronics.com] On Behalf Of Jay Caldwell
Sent: Friday, April 25, 2008 2:21 PM
Subject: AeroElectric-List: Throttle Servo
I am building a CH-801 and am in need of a dual throttle setup so one canm
fly from eithr side given there is a "Y" shaped stick in the center.
I had in mind a "fly by wire" arrangement. If I could connect a servo to t
he "throttle door", I could then conect a throttle quadrant with a "pot" co
nnected to it and actuate the throttle from either side; Pilot with left ha
nd and Co pilot with right hand.. Using a switch I could assign the servo
to the Pilot or Copilot.
Any ideas?
Jay F. Caldwell
Owner, Caldwell Systems Engineering (CSE), LLC
4181 Tamilynn Court
San Diego, CA 92122
Office email caldwell(at)mswin.net
Voice 858.453.4594
Facsimile 858.452.1560
Work 619.562.0885
Mobile 858.336.0394
Hanger 760-789-2557
________________________________________________________________________________
| From: | "Ed Anderson" <eanderson(at)carolina.rr.com> |
| Subject: | Re: Throttle Servo |
Jay, I know of someone who is developing a "fly by wire" throttle body
using the Mazda "Fly by wire throttle body - Rx-8 auto". He is
installing it in his Rv-8. He produces electronic devices for aircraft.
I have seen it in operation - not only is it very neat, but it also
opens up possibility of some automatic engine control features such as:
1. Setting throttle to maintain engine rpm
2. Setting throttle to maintain engine manifold pressure
3. Setting throttle to maintain a constant fuel flow
etc.
Contact me off-line if interested.
Ed Anderson
Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
eanderson(at)carolina.rr.com
http://www.andersonee.com
http://members.cox.net/rogersda/rotary/configs.htm#N494BW
http://www.dmack.net/mazda/index.html
----- Original Message -----
From: Jay Caldwell
To: aeroelectric-list(at)matronics.com
Sent: Friday, April 25, 2008 5:20 PM
Subject: AeroElectric-List: Throttle Servo
I am building a CH-801 and am in need of a dual throttle setup so one
canm fly from eithr side given there is a "Y" shaped stick in the
center.
I had in mind a "fly by wire" arrangement. If I could connect a servo
to the "throttle door", I could then conect a throttle quadrant with a
"pot" connected to it and actuate the throttle from either side; Pilot
with left hand and Co pilot with right hand.. Using a switch I could
assign the servo to the Pilot or Copilot.
Any ideas?
Jay F. Caldwell
Owner, Caldwell Systems Engineering (CSE), LLC
4181 Tamilynn Court
San Diego, CA 92122
Office email caldwell(at)mswin.net
Voice 858.453.4594
Facsimile 858.452.1560
Work 619.562.0885
Mobile 858.336.0394
Hanger 760-789-2557
________________________________________________________________________________
| From: | <gmcjetpilot(at)yahoo.com> |
| Subject: | Re: ELT Antenna for Fiberglass aircraft (any aircraft) |
Yes loss of satellite monitoring of 121.5 Mhz will make
little difference, but you are also losing 246Mhz
completely. That is a big difference. that means the only
ELT you will have is something that transmit less than a
kids walkie-talkie (100mW) and has a range of a mile or
two at BEST. Basically they have to know where you are
first before they can find you.
The only way you really will be FOUND is with a
satellite signal, at least in a large and/or remote area.
What does that mean, no one will come to look for you.
Remember Steve Fossett was well-known for his world
record-setting adventures in balloons, sailboats, gliders,
and powered aircraft. He took off in Sep 2007. Never
been found despite a search that was very extensive, a
1000 times more extensive than if you or I went
missing.
406Mhz is better in every way. Resist all you want but I
find that foolish if flying over any remotely sparsely
populated area, especially if you are responsible for
other peoples lives, aka passengers, not to have one.
At least get a PLB.
BTW 406Mhz is 5 watt pulses which is one of the many
reasons its better. 121.5Mhz 100mW, do the math.
RUBBER DUCKIE ANTENNA - STUPID ON A GOOD DAY
Its best to use the antenna that comes with the ELT. If
you know anything about RUBBER DUCKIE antennas
you know they suck. There is NO magic in antennas
and you need length (to resonate at the proper freq).
"Duckie" base loaded coil non-ground plane mono-pole
antennas are a HUGE sacrifice. They really are terrible
even for the little handheld receiver or transceiver they
where designed for, meaning a super big compromise.
BTW key words, "they where designed for", meand they
where never made for your ELT ever; they WILL cause
HUGE loss in efficiency. It's you life, so beware.
LET ME SHOW YOU WHAT WE ARE TALKING ABOUT
http://tiny.cc/9tGKn
-Verses-
http://www.edmo.com/modules/products/xarimages/Large/455-5044.jpg
http://img292.imageshack.us/img292/5631/eltantennasls8.jpg
(RV's w/ ELT antenna's zoom in and see if you can see them)
"THERE IS NO SUBSTITUTE FOR AN EXTERNALLY MOUNTED 1/2 WAVE DIPOLE"
(Our whips are 1/4 wave but act as 1/2 wave on a ground plane)
You are dealing with 121.5Mhz @ 100 mW (milli watts)
power. You might as well have a string-N-can if you
screw with these dumb little excuses for an antenna.
Forget 246Mhz its gone. No birds in the sky are looking.
If talking 406Mhz they are already super short. 406Mhz
is UHF and the antenna is SMALL, PUT IT OUTSIDE
WHERE IT BELONGS.
If you get a new 406Mhz and I think you should, you
will most likely have two antennas one for 121.5Mhz
and one for 406Mhz. As you know as the freq goes up
the wave length goes down and so does antenna
length. Artex has the one antenna version that handles
both freqs (121.5 and 406). It is OK to have a longer
antenna (for 121.5mhz) that also handles the higher
UHF freq (ie 406Mhz) if designed properly.
It is not OK to go the other way, have a short antenna
(rubber duckie) for a radio that needs a long antenna. You
can always go longer bit not shorter. Again there is NO
magic or violations of physics. "Trick" the radio single all
you want but it knows it and there will be loss of efficiency.
A 406 Mhz antenna is so short no rubber duckie need apply.
This C-130 doing a grid at 6,000 agl (mile up)
at 220kts is looking for you. If your weak signal is
made weaker with a rubber duck or directional loop they
might not "hear you", even if they fly directly overhead.
121.5Mhz is for LOCAL DF steer only after they found
you.
Antenna's are a special deal, engineered to work with
that specific transmitter, power & freq. Unless a radio expert,
who knows antenna theory and how to test it, have
the equipment and knowledge to do so, screwing with it
just to make your plane look good is kind silly in my
opinion.
LOOP ANTENNAS BAD FOR ELT's (my opinion)
Loop Antenna? Well when I hear loop, normally I get
excited, because loops are directional, give good GAIN
if pointed and tuned properly and have good noise
rejection. However loop antennas claim to fame is
for lower freqs (HF or MW). Since HF and MW wave
lengths are long, their antennas are long (10' to ++100'),
so a loop is a good solution for getting the required length
to resonate at those long wave freqs a still be somewhat
compact in size. However the directional part is a draw back
for a "FIND ME" Beacon which should be omnidirectional.
THE WHEEL, REINVENTED, WHY?
Why do we need to reinvent the wheel when its already
been done for us. Yes I know you glue and string
airplane guys want to hide your antennas. OK than put
a 1/2 wave in the vertical stab or put a 1/4 wave
reflected dipole (acts like 1/2 wave) with a good grd plane.
A good 1/2 wave or 1/4 wave reflected dipole is great for
the HF and UHF band.
The Wings and Wheels antennas for gliders, like their
non ground plane 1/2 wave will work. Again who knows
how it will really work if the real world; again 121.5Mhz is
pretty lame "to be found" with anyway. At least these
antennas are professionally designed and made. There
is nothing wrong with making your own antenna if you
know what you are doing, but if your are making a smaller
antenna or one stuffed in a wing top or in between the
vert and horz stabs with horz polarization or screwing on
a rubber duckie antenna thinking you are being clever you
are not.
Do some test with your home-brew deal. Go to a big airport
and with-in the first 5 min of the hour with no more than
5 sec "on time" check range with a receiver and sensitive
signal meter. May be the CAP can help w/ some gear? The
reciver antenna can be a whip, loop or beam, great for DF
(Direction finding), but the latter two req you know where point.
Even have get some one to fly over, with receiver/meter. See
how far out you can transmit in different directions. I think you
will be disappointed with hidden antennas laying down inside
fuselages or rubber duckies. External and vertical with good
ground plane will maximize performance. Now we can get into
what if the plane flips but save that for a different time.
406Mhz antennas are so small just put them
outside the plane with a ground plane. It will not cause
drag or distract from the beauty of your plane.
#1 advice, USE THE ANTENNA THAT CAME WITH IT
and mount it as instructed. It really is the Law, since
the ELT is a TYPE certificate item. The ELT and its
installation is one of the few things an experimental
must have, must be TYPE CERT (including installation)
if operations require you having an ELT at all. I know
we get away with some crazy stuff but its your life.
Unless you are a Ham radio Gen / Extra and have the
wherewithal (& equipment) to test and evaluate your
custom ELT antenna system, than I would use the KISS
method and mount the antenna outside per the ELT's
instructions. A 121.5 Mhz elt whip cost you about 1/8 to
1/4 mph loss at 220 mph. I don't think you'll notice it. A
406Mhz Ant is the size of transponder & almost invisible
with no drag. Make it an airplane. Airplanes have antennas.
Fiberglass guys have more antenna options but a 406Mhz elt
should be the first option.
Just MY opinion, George
---------------------------------
Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Throttle Servo |
Good Afternoon Jay,
I know this is an electrical list, but I think I would look at a Stearman or
other tandem cockpit airplane for guidance.
Even the J-3 Cub uses two throttles that move at the same time.
I think a mechanical system would be better. As a flight instructor, I also
like the idea of both controls moving when either one is actuated. One of the
things I don't like about the Air Bus is that you can't see what movements
the copilot is making on his/her side stick.
I would think a mechanical setup would be easy to arrange, very economical,
and very reliable.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
628 West 86th Street
Downers Grove, IL 60516
630 985-8502
Stearman N3977A
Brookeridge Air Park LL22
In a message dated 4/25/2008 4:26:45 P.M. Central Daylight Time,
caldwelljf(at)sbcglobal.net writes:
I am building a CH-801 and am in need of a dual throttle setup so one can
fly from either side given there is a "Y" shaped stick in the center.
I had in mind a "fly by wire" arrangement. If I could connect a servo to
the "throttle door", I could then connect a throttle quadrant with a "pot"
connected to it and actuate the throttle from either side; Pilot with left hand
and Co pilot with right hand.. Using a switch I could assign the servo to the
Pilot or Copilot.
Any ideas?
Jay F. Caldwell
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Hinde, Frank George (Corvallis)" <frank.hinde(at)hp.com> |
Buy a constant speed prop!...Does all of this, more efficiently (cus closin
g a throttle is a poor thing to do efficiency wise;...at least at cruise) a
nd its safer!
One dirty pot and does you throttle go to idle?..Like everything else all t
he fialure modes have to be understood.
Frank
________________________________
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectr
ic-list-server(at)matronics.com] On Behalf Of Ed Anderson
Sent: Friday, April 25, 2008 2:46 PM
Subject: Re: AeroElectric-List: Throttle Servo
Jay, I know of someone who is developing a "fly by wire" throttle body usin
g the Mazda "Fly by wire throttle body - Rx-8 auto". He is installing it i
n his Rv-8. He produces electronic devices for aircraft. I have seen it i
n operation - not only is it very neat, but it also opens up possibility of
some automatic engine control features such as:
1. Setting throttle to maintain engine rpm
2. Setting throttle to maintain engine manifold pressure
3. Setting throttle to maintain a constant fuel flow
etc.
Contact me off-line if interested.
Ed Anderson
Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
eanderson(at)carolina.rr.com
http://www.andersonee.com
http://members.cox.net/rogersda/rotary/configs.htm#N494BW
http://www.dmack.net/mazda/index.html
----- Original Message -----
From: Jay Caldwell<mailto:caldwelljf(at)sbcglobal.net>
Sent: Friday, April 25, 2008 5:20 PM
Subject: AeroElectric-List: Throttle Servo
I am building a CH-801 and am in need of a dual throttle setup so one canm
fly from eithr side given there is a "Y" shaped stick in the center.
I had in mind a "fly by wire" arrangement. If I could connect a servo to t
he "throttle door", I could then conect a throttle quadrant with a "pot" co
nnected to it and actuate the throttle from either side; Pilot with left ha
nd and Co pilot with right hand.. Using a switch I could assign the servo
to the Pilot or Copilot.
Any ideas?
Jay F. Caldwell
Owner, Caldwell Systems Engineering (CSE), LLC
4181 Tamilynn Court
San Diego, CA 92122
Office email caldwell(at)mswin.net
Voice 858.453.4594
Facsimile 858.452.1560
Work 619.562.0885
Mobile 858.336.0394
Hanger 760-789-2557
href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.ma
tronics.com/Navigator?AeroElectric-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
________________________________________________________________________________
| From: | "Matt Prather" <mprather(at)spro.net> |
I know fly by wire makes everybody's hair stand up.. But I don't think
it's a terrible idea. It would definitely require careful design and
implementation, but it could certainly be lighter and lower maintenance.
A few thoughts:
The control doesn't have to use a pot to generate signal. An optical
position sensor seems feasible to me. Or maybe a capacitive sensor.
The throttle levers could be motorized - effectively linking them together
- and provide feedback. Not trivial, but possible. A switch on the panel
would select which throttle handle was in charge, and which was just
indicating.
It could also be relatively easy to make the throttle body spring loaded
to WOT - achieving this position if power is lost/cut to the
controller/positioner. A reasonable fail safe not unlike our existing
all-mechanic systems.
At would also be reasonably easy to put a mechanical echo throttle control
in the middle of the panel. It would just ride along with what the
whatever position the throttle body was in (indicating) - unless you had a
control failure. If the power to the system is cut, this is now the
control. The ergonomics might be less than optimal, but it would allow
you to control the engine output.
All that said, it should be fairly easy to make an all mechanical setup.
You could have a torque tube attached to the panel which translates the
throttle movement from one side to the other. I kind of wonder about how
to make a friction lock work, but I'm sure it's possible.
If it were mine, I'd use a mechanical throttle on each side of the panel
but only one mixture (and prop) control - in the middle.
Regards,
Matt-
> Buy a constant speed prop!...Does all of this, more efficiently (cus
> closing a throttle is a poor thing to do efficiency wise;...at least at
> cruise) and its safer!
>
> One dirty pot and does you throttle go to idle?..Like everything else all
> the fialure modes have to be understood.
>
> Frank
>
> ________________________________
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ed
> Anderson
> Sent: Friday, April 25, 2008 2:46 PM
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: Throttle Servo
>
> Jay, I know of someone who is developing a "fly by wire" throttle body
> using the Mazda "Fly by wire throttle body - Rx-8 auto". He is installing
> it in his Rv-8. He produces electronic devices for aircraft. I have seen
> it in operation - not only is it very neat, but it also opens up
> possibility of some automatic engine control features such as:
>
> 1. Setting throttle to maintain engine rpm
> 2. Setting throttle to maintain engine manifold pressure
> 3. Setting throttle to maintain a constant fuel flow
> etc.
>
> Contact me off-line if interested.
>
> Ed Anderson
>
> Ed Anderson
> Rv-6A N494BW Rotary Powered
> Matthews, NC
> eanderson(at)carolina.rr.com
> http://www.andersonee.com
> http://members.cox.net/rogersda/rotary/configs.htm#N494BW
> http://www.dmack.net/mazda/index.html
> ----- Original Message -----
> From: Jay Caldwell<mailto:caldwelljf(at)sbcglobal.net>
> To:
> aeroelectric-list(at)matronics.com
> Sent: Friday, April 25, 2008 5:20 PM
> Subject: AeroElectric-List: Throttle Servo
>
> I am building a CH-801 and am in need of a dual throttle setup so one canm
> fly from eithr side given there is a "Y" shaped stick in the center.
>
> I had in mind a "fly by wire" arrangement. If I could connect a servo to
> the "throttle door", I could then conect a throttle quadrant with a "pot"
> connected to it and actuate the throttle from either side; Pilot with left
> hand and Co pilot with right hand.. Using a switch I could assign the
> servo to the Pilot or Copilot.
>
> Any ideas?
>
> Jay F. Caldwell
> Owner, Caldwell Systems Engineering (CSE), LLC
> 4181 Tamilynn Court
> San Diego, CA 92122
> Office email caldwell(at)mswin.net
> Voice 858.453.4594
> Facsimile 858.452.1560
> Work 619.562.0885
> Mobile 858.336.0394
> Hanger 760-789-2557
>
>
> href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.matronics.com/Navigator?AeroElectric-List
> href="http://forums.matronics.com">http://forums.matronics.com
> href="http://www.matronics.com/contribution">http://www.matronics.com/c
>
>
________________________________________________________________________________
| From: | "Ed Anderson" <eanderson(at)carolina.rr.com> |
| Subject: | Re: Throttle Servo |
No doubt, a CS is more efficient, but also very much more costly to
acquire and properly maintain and props also fail - (single point of
failure? - unless you fly a twin). A case could be make that a fixed
pitch prop is inherently more safe than a CS. But, many (if not most of
us) would love to have a light weight (inexpensive) CS hung off our nose
(or tail as the case may be) even if less reliable.
Anything mechanical or electronic can and will eventually fail (cables
also break, bind or become detached). Check on the FAA accident list
and observe how frequently an engine (or some related component) is
cited in the accident report. Yet, we have been producing and flying
with essentially the same engine design for 60 years.
One could point out that by virtue of our decision to be airborne
(without naturally bestowed wings) we are increasing our risk, yet, we
take that risk. Because, most of us believe (correctly or not) that we
mitigate that risk in our favor by our awareness, knowledge, skills and
understanding.
Every new approach in aviation has certainly carried risks - frequently
not fully appreciate at the beginning- but techniques and technology
has generally overcome the faults to give us increased reliability and
safety. Space flight relies almost exclusively on electronic controls
vice mechanical ones - simply because it has been repeatedly shown that
properly designed electronic systems fail less often than mechanical
ones and are generally much easier to build redundancy/safe guards into
in event they should fail.
Thinking about Jimmy Dolittle and the other participants in first
"instrument" flights come to mind. Hydraulic brakes replacing cables,
GPS, autopilots, heated pitot tubes, electric gyros, electric fuel
pumps, etc., are just a few of what once were "new " technology now
commonly accepted.
Fortunately, we have sufficient difference of opinions and views on this
list that each side gets presented and the inquiring mind can make a
(hopefully) informed decision. So I also urge caution being undertaken
when trying a "different" approach - make certain you understand the
risks as well as your ability to assess and mitigate them - you may fool
yourself, but not the laws of physics. That said, if no one tried
anything new - there would be no advancement in aviation.
But, to answer your specific question about possible pot malfunction -
while environmentally sealed pots are readily available, if I were to
design a fly-by-wire throttle, I would probably go with a digital pot
which has no physical parts to wear and which can have values stored in
nonvolatile memory to handle such things as lost of control signal, etc
.
Excerpt from a producer of such devices:
Digital potentiometers are far more reliable than mechanical
potentiometers. Digital pots can easily guarantee 50,000 writing cycles,
while the mechanical parts rate only a few thousand, and sometimes only
a few hundred.
http://www.maxim-ic.com/appnotes.cfm/appnote_number/3417/
Best Regards
Ed
- ----- Original Message -----
From: Hinde, Frank George (Corvallis)
To: aeroelectric-list(at)matronics.com
Sent: Friday, April 25, 2008 6:03 PM
Subject: RE: AeroElectric-List: Throttle Servo
Buy a constant speed prop!...Does all of this, more efficiently (cus
closing a throttle is a poor thing to do efficiency wise;...at least at
cruise) and its safer!
One dirty pot and does you throttle go to idle?..Like everything else
all the fialure modes have to be understood.
Frank
-------------------------------------------------------------------------
-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ed
Anderson
Sent: Friday, April 25, 2008 2:46 PM
To: aeroelectric-list(at)matronics.com
Subject: Re: AeroElectric-List: Throttle Servo
Jay, I know of someone who is developing a "fly by wire" throttle body
using the Mazda "Fly by wire throttle body - Rx-8 auto". He is
installing it in his Rv-8. He produces electronic devices for aircraft.
I have seen it in operation - not only is it very neat, but it also
opens up possibility of some automatic engine control features such as:
1. Setting throttle to maintain engine rpm
2. Setting throttle to maintain engine manifold pressure
3. Setting throttle to maintain a constant fuel flow
etc.
Contact me off-line if interested.
Ed Anderson
Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
eanderson(at)carolina.rr.com
http://www.andersonee.com
http://members.cox.net/rogersda/rotary/configs.htm#N494BW
http://www.dmack.net/mazda/index.html
----- Original Message -----
From: Jay Caldwell
To: aeroelectric-list(at)matronics.com
Sent: Friday, April 25, 2008 5:20 PM
Subject: AeroElectric-List: Throttle Servo
I am building a CH-801 and am in need of a dual throttle setup so
one canm fly from eithr side given there is a "Y" shaped stick in the
center.
I had in mind a "fly by wire" arrangement. If I could connect a
servo to the "throttle door", I could then conect a throttle quadrant
with a "pot" connected to it and actuate the throttle from either side;
Pilot with left hand and Co pilot with right hand.. Using a switch I
could assign the servo to the Pilot or Copilot.
Any ideas?
Jay F. Caldwell
Owner, Caldwell Systems Engineering (CSE), LLC
4181 Tamilynn Court
San Diego, CA 92122
Office email caldwell(at)mswin.net
Voice 858.453.4594
Facsimile 858.452.1560
Work 619.562.0885
Mobile 858.336.0394
Hanger 760-789-2557
href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.
matronics.com/Navigator?AeroElectric-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
ist">http://www.matronics.com/Navigator?AeroElectric-List
ics.com
.matronics.com/contribution
________________________________________________________________________________
| From: | "Richard Girard" <jindoguy(at)gmail.com> |
| Subject: | Re: Throttle Servo |
I won't comment either way on the safety of a fly by wire throttle, but I
think Ed is right about the possibilities it presents. The unit in my Toyota
truck is both very reliable and the cruise control is eerily accurate and
easy to adjust upward or downward as needed. Why reinvent the wheel when you
could snag everything out of a wrecking yard?
On Fri, Apr 25, 2008 at 6:19 PM, Matt Prather wrote:
> >
>
> I know fly by wire makes everybody's hair stand up.. But I don't think
> it's a terrible idea. It would definitely require careful design and
> implementation, but it could certainly be lighter and lower maintenance.
>
> A few thoughts:
>
> The control doesn't have to use a pot to generate signal. An optical
> position sensor seems feasible to me. Or maybe a capacitive sensor.
>
> The throttle levers could be motorized - effectively linking them together
> - and provide feedback. Not trivial, but possible. A switch on the panel
> would select which throttle handle was in charge, and which was just
> indicating.
>
> It could also be relatively easy to make the throttle body spring loaded
> to WOT - achieving this position if power is lost/cut to the
> controller/positioner. A reasonable fail safe not unlike our existing
> all-mechanic systems.
>
> At would also be reasonably easy to put a mechanical echo throttle control
> in the middle of the panel. It would just ride along with what the
> whatever position the throttle body was in (indicating) - unless you had a
> control failure. If the power to the system is cut, this is now the
> control. The ergonomics might be less than optimal, but it would allow
> you to control the engine output.
>
> All that said, it should be fairly easy to make an all mechanical setup.
> You could have a torque tube attached to the panel which translates the
> throttle movement from one side to the other. I kind of wonder about how
> to make a friction lock work, but I'm sure it's possible.
>
> If it were mine, I'd use a mechanical throttle on each side of the panel
> but only one mixture (and prop) control - in the middle.
>
>
> Regards,
>
> Matt-
>
>
> > Buy a constant speed prop!...Does all of this, more efficiently (cus
> > closing a throttle is a poor thing to do efficiency wise;...at least at
> > cruise) and its safer!
> >
> > One dirty pot and does you throttle go to idle?..Like everything else all
> > the fialure modes have to be understood.
> >
> > Frank
> >
> > ________________________________
> > From: owner-aeroelectric-list-server(at)matronics.com
> > [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ed
> > Anderson
> > Sent: Friday, April 25, 2008 2:46 PM
> > To: aeroelectric-list(at)matronics.com
> > Subject: Re: AeroElectric-List: Throttle Servo
> >
> > Jay, I know of someone who is developing a "fly by wire" throttle body
> > using the Mazda "Fly by wire throttle body - Rx-8 auto". He is
> installing
> > it in his Rv-8. He produces electronic devices for aircraft. I have
> seen
> > it in operation - not only is it very neat, but it also opens up
> > possibility of some automatic engine control features such as:
> >
> > 1. Setting throttle to maintain engine rpm
> > 2. Setting throttle to maintain engine manifold pressure
> > 3. Setting throttle to maintain a constant fuel flow
> > etc.
> >
> > Contact me off-line if interested.
> >
> > Ed Anderson
> >
> > Ed Anderson
> > Rv-6A N494BW Rotary Powered
> > Matthews, NC
> > eanderson(at)carolina.rr.com
> > http://www.andersonee.com
> > http://members.cox.net/rogersda/rotary/configs.htm#N494BW
> > http://www.dmack.net/mazda/index.html
> > ----- Original Message -----
> > From: Jay Caldwell<mailto:caldwelljf(at)sbcglobal.net>
> > To:
> > aeroelectric-list(at)matronics.com
> > Sent: Friday, April 25, 2008 5:20 PM
> > Subject: AeroElectric-List: Throttle Servo
> >
> > I am building a CH-801 and am in need of a dual throttle setup so one
> canm
> > fly from eithr side given there is a "Y" shaped stick in the center.
> >
> > I had in mind a "fly by wire" arrangement. If I could connect a servo to
> > the "throttle door", I could then conect a throttle quadrant with a "pot"
> > connected to it and actuate the throttle from either side; Pilot with
> left
> > hand and Co pilot with right hand.. Using a switch I could assign the
> > servo to the Pilot or Copilot.
> >
> > Any ideas?
> >
> > Jay F. Caldwell
> > Owner, Caldwell Systems Engineering (CSE), LLC
> > 4181 Tamilynn Court
> > San Diego, CA 92122
> > Office email caldwell(at)mswin.net
> > Voice 858.453.4594
> > Facsimile 858.452.1560
> > Work 619.562.0885
> > Mobile 858.336.0394
> > Hanger 760-789-2557
> >
> >
> >
> > href="http://www.matronics.com/Navigator?AeroElectric-List">
> http://www.matronics.com/Navigator?AeroElectric-List
> > href="http://forums.matronics.com">http://forums.matronics.com
> > href="http://www.matronics.com/contribution">http://www.matronics.com/c
> >
> >
> >
> >
> >
> >
> >
>
>
________________________________________________________________________________
| From: | John Swartout <jgswartout(at)earthlink.net> |
| Subject: | Mechanical question |
I'll take a look at the Click Bond website. I see you have to register (Grrrrrrr!!!!)
to look at their products. Thanks for the tip. I have a hunch I'll wish
I'd known about them about 3,000 hours of airplane-building ago.
John
-----Original Message-----
>From: longg(at)pjm.com
>Sent: Apr 25, 2008 8:43 AM
>To: aeroelectric-list(at)matronics.com
>Subject: RE: AeroElectric-List: Mechanical question
>
>
>The simple and elegant solution is to use a dab of epoxy. I will stick
>to anything. Position the holder such that you can get the top off to
>service the fuse. If you want to buy something take a look at click-bond
>products. They have a fastener for everything you could ever want to tie
>down in your airplane. Warning - they are not exactly cheap.
>
>-----Original Message-----
>From: owner-aeroelectric-list-server(at)matronics.com
>[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jim
>Sent: Thursday, April 24, 2008 9:08 PM
>To: aeroelectric-list(at)matronics.com
>Subject: Re: AeroElectric-List: Mechanical question
>
>
>John,
>
>The Buss fuse holders that I used had recessed holes suitable for number
>8
>machine screws. The local hardware store aircraft section supplied
>screws of
>correct length.
>
>Jim in Kelowna
>
>----- Original Message -----
>From: "John Swartout" <jgswartout(at)earthlink.net>
>To:
>Sent: Thursday, April 24, 2008 4:43 PM
>Subject: AeroElectric-List: Mechanical question
>
>
>>
>>
>>
>> Does anyone have a nice, elegant method for mounting on a flat surface
>
>> the
>> in-line automotive-type fuse-holder sold by B&C? It has no built-in
>> mounting tab or any such thing.
>>
>> Thanks.
>>
>>
>>
>>
>>
>>
>> --
>> Checked by AVG.
>> 7:24 AM
>>
>>
>
>
________________________________________________________________________________
| From: | bill(at)waterbirds.com |
| Subject: | Re: Your email to Waterbirds |
--- MIME Errors - No Plain-Text Section Found ---
A message with no text/plain MIME section was received.
The entire body of the message was removed. Please
resend the email using Plain Text formatting.
HOTMAIL is notorious for only including an HTML section
in their client's default configuration. If you're using
HOTMAIL, please see your email application's settings
and switch to a default mail option that uses "Plain Text".
--- MIME Errors No Plain-Text Section Found ---
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Mechanical question |
FWIW - I'm a big Click Bond fan, and have used several of their products
extensively in my project. The retail source in the US is
http://theflightshop.com, and you don't have to register before looking.
Very helpful and knowledgeable folks there. Email me off list if I can help
in any way.
Ron
Murphy Rebel
http://n254mr.com
On Fri, Apr 25, 2008 at 10:39 PM, John Swartout
wrote:
> jgswartout(at)earthlink.net>
>
> I'll take a look at the Click Bond website. I see you have to register
> (Grrrrrrr!!!!) to look at their products. Thanks for the tip. I have a
> hunch I'll wish I'd known about them about 3,000 hours of airplane-building
> ago.
>
> John
>
________________________________________________________________________________
| From: | "Jim McBurney" <jmcburney(at)pobox.com> |
| Subject: | Re: Throttle Servo |
Hi, Jay (and List),
The Zenith demo 801 has dual throttle controls. They KISSed the problem:
ran both cables to the carb, connected both to the throttle lever. It works
well, but you can't use a vernier throttle. Zenith used friction-lock
throttles, took the friction bushing out of the secondary (right-seat)
control. There are several ideas in the Matronics Zenith list archives that
have been done, mostly on 601s. Check it out.
Blue skies and tailwinds
Jim
CH-801
DeltaHawk diesel
Augusta GA
90% done, 90% left
________________________________________________________________________________
| From: | Matt Dralle <dralle(at)matronics.com> |
| Subject: | Four New Email Lists At Matronics!! |
Dear Listers,
I have added four new Lists to the Matronics line up today. These include the
following categories:
Citabria-List Citabria, Decathlon, Scout, and Champ
Zenith601-List Zenair Zodiac CH 601
Zenith640-List Zenair Zodiac CH 640
Zenith701801-List Zenair STOL CH 701 and CH 801
All services are enabled and now available including Search, Browse, Digest, Archives,
Forums, Chat, etc., etc. etc...:
Citabria:
http://www.matronics.com/navigator?citabria-list
Zenith601:
http://www.matronics.com/navigator?zenith601-list
Zenith640:
http://www.matronics.com/navigator?zenith640-list
Zenith701801:
http://www.matronics.com/navigator?zenith701801-list
To subscribe, go to the Matronics Email List Subscription Form:
http://www.matronics.com/subscribe
To check the new Lists out on the Matronics Forum go here:
http://forums.matronics.com
Enjoy the new Lists!! Don't forget me during the Fund Raiser! :-)
Best regards,
Matt Dralle
Matronics Email List Administrator
________________________________________________________________________________
| From: | RScott <rscott(at)cascadeaccess.com> |
Best source I have found for my Artex ELT 110 is from Chief Aircraft in
Grant's Pass, Oregon.
Cheaper than from Artex themselves.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Mechanical question |
>Besides the aggravation of having to register to view their products, I
>find their products not suitable for aviation. I have used their
>nutplates and ty wrap anchors and found both to be unsuitable for use in
>my airplane. Their adhesive does not adhere well. For example, of the
>nutplates I installed (about 40), half came loose. Perhaps I didn't do a
>good job of applying the adhesive, but I doubt I would have screwed up 20
>of them. The reasons I don't like using Click-Bond nutplates is because:
>1. Nutplates are typically used in locations that are otherwise difficult
>to access. When the nutplate comes unglued (it's a matter of time) you
>cannot remove the screw to replace it because the nutplate spins with the
>screw. The nutplates are shorter than normal riveted nutplates and thus
>they can spin in a small space. If the nutplate location is not
>accessable, you have to cut through panels to get to it.
>2. If (when) a nutplate comes loose and frees itself from the screw (or
>falls off while removing a screw), it can become FOD inside the airplane
>to get jammed in (you name it) controls, cables, etc.
>Ask me how I've learned these things.
>Personally, I threw away my $100 worth of Click-Bond products. I didn't
>give them to anyone because I didn't want anyone else to suffer the same
>aggravations and fears I did. I use only normal nutplates or screws with nuts.
>Perhaps others have had better results with Click-Bond, but I am not
>satisfied with them and cannot recommend them.\
It would be useful to know how the system is failing you.
They're used all over the airplanes at Hawker-Beech.
I've never installed any personally but many folks I work
around have used them.
I will note that the only airplanes/places I specifically
recall their use is on the composite surfaces of structure
and fuselage. It may be that the recommended adhesive for
aluminum surfaces is different. I wish you hadn't pitched
the surplus, it would have been an interesting experiment
to see what was happening.
Bob . . .
________________________________________________________________________________
| From: | bill(at)waterbirds.com |
| Subject: | Re: Your email to Waterbirds |
--- MIME Errors - No Plain-Text Section Found ---
A message with no text/plain MIME section was received.
The entire body of the message was removed. Please
resend the email using Plain Text formatting.
HOTMAIL is notorious for only including an HTML section
in their client's default configuration. If you're using
HOTMAIL, please see your email application's settings
and switch to a default mail option that uses "Plain Text".
--- MIME Errors No Plain-Text Section Found ---
________________________________________________________________________________
| From: | "Henry Trzeciakowski" <hammer408(at)comcast.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
Bob:
I'm planning to use copper bar in lieu of "fat wire" in 2 areas:
1- from the Starter Contactor to Master Battery Contactor - 1/8" (.125)
thick
2- and from the Starter Contactor to the 60 amp Current Limiter - 1/16"
(.063)...
My question is: Is the thickness of the copper bar appropriate?
Thanks
Hank
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
>
>
>Bob:
>
>I'm planning to use copper bar in lieu of "fat wire" in 2 areas:
>
>1- from the Starter Contactor to Master Battery Contactor - 1/8" (.125)
>thick
>
>2- and from the Starter Contactor to the 60 amp Current Limiter - 1/16"
>(.063)...
>
>My question is: Is the thickness of the copper bar appropriate?
>
>Thanks
>
>Hank
Those are PLENTY thick . . . if it's stuff you already
have laying around and don't mind working with copper
(machines like peanut butter) it will be find. If you're
of a mind to make the task a bit easier, .032" x 3/4"
brass strips like #243 found at:
http://www.udisco.com/hobbies/inv/KS.HTM
are much easier to work with.
Bob . . .
________________________________________________________________________________
| From: | "Henry Trzeciakowski" <hammer408(at)comcast.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
Bob:
I already have the copper bars and, if fact, they are cut and ready to bend
and install......they were a lottle hard to work with !!!!
I'm somewhat surprised that you suggest .032: isn't that a little thin,
considering these bars are replacing 4awg wire ????
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
Sent: Sunday, April 27, 2008 7:44 AM
Subject: Re: AeroElectric-List: Re: Copper Bar vs "FAT" wire
>
>
> >
> >
> >Bob:
> >
> >I'm planning to use copper bar in lieu of "fat wire" in 2 areas:
> >
> >1- from the Starter Contactor to Master Battery Contactor - 1/8" (.125)
> >thick
> >
> >2- and from the Starter Contactor to the 60 amp Current Limiter - 1/16"
> >(.063)...
> >
> >My question is: Is the thickness of the copper bar appropriate?
> >
> >Thanks
> >
> >Hank
>
> Those are PLENTY thick . . . if it's stuff you already
> have laying around and don't mind working with copper
> (machines like peanut butter) it will be find. If you're
> of a mind to make the task a bit easier, .032" x 3/4"
> brass strips like #243 found at:
>
> http://www.udisco.com/hobbies/inv/KS.HTM
>
> are much easier to work with.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Ralph Finch" <rgf(at)dcn.davis.ca.us> |
| Subject: | Re: Copper Bar vs "FAT" wire |
I assume your motive for using a bar instead of wire is higher current
capacity -> lower resistance -> lower voltage drop and power loss.
I'm a hydraulic engineer for the California Dept. of Water Resources...and
years ago took a tour of our biggest lift station at the base of the
Tehachapi Mtns. A single lift of about 2,000 feet, 4,500 cfs pumping rate.
That requires a lot of power. I remember well the "wire" they use to carry
the current (which I think was about 1000 amps at 10-12kV): a tube a few
inches in diameter. The electrical engineer said current is carried on the
surface and the tube gave them the surface they needed.
Not suggesting you use a tube, but maybe braided multi-strand wire is better
than a single bar?
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Henry
Trzeciakowski
Sent: Sunday, April 27, 2008 8:58 AM
Subject: AeroElectric-List: Re: Copper Bar vs "FAT" wire
-->
Bob:
I'm planning to use copper bar in lieu of "fat wire" in 2 areas:
1- from the Starter Contactor to Master Battery Contactor - 1/8" (.125)
thick
2- and from the Starter Contactor to the 60 amp Current Limiter - 1/16"
(.063)...
My question is: Is the thickness of the copper bar appropriate?
Thanks
Hank
________________________________________________________________________________
| From: | "Dennis Johnson" <pinetownd(at)volcano.net> |
| Subject: | Epoxy to Aluminum |
Greetings,
As part of building a composite airplane, I studied everything I could
find about epoxies, materials, and adhesive bonding in general. I
concluded that I did not have the ability to make an epoxy bond to
aluminum that I could be confident that it wouldn't fail.
The problem is that aluminum begins oxidizing immediately after
cleaning. No matter how quick you are, unless you use extraordinary
measures, there will be aluminum oxide on the surface you are bonding.
Aluminum oxide has relatively low strength. The epoxy bonds well to the
aluminum oxide, but the aluminum oxide isn't stuck very well to the
underlying aluminum. After some number of hot/cold and wet/dry cycles,
the bond may weaken enough to fail.
Obviously, Boeing and others solved this problem long ago. However,
based on the great reference book, "Composite Basics," by Andrew
Marshall, their methods aren't practical for most of us homebuilders.
>From chapter 11, Marshall says, "Unfortunately, both the FPL etch and
the PAA treatments (the ones widely and successfully used in the
industry) involve extensive chemical control and a large investment in
equipment."
As an interesting aside, he describes an industry standard "wedge" test
where two .125" thick aluminum pieces are bonded together. After
curing, a wedge is driven into the end of the assembly, between the two
pieces of aluminum, which forces the bond to break at that point. A
mark is placed at the point where the fracture stops. The test piece is
then placed into a warm, wet chamber for one hour. The assembly is then
removed and the additional distance the crack propagated during the
warm/wet test is measured. If the crack grew less than three-fourths of
an inch, the bond is considered to be good for life. Marshall says that
if the aluminum was cleaned but not chemically treated, the assembly
will likely totally delaminate during the one hour test!
Since I didn't have the ability to duplicate Boeing's chemical treatment
process, I didn't make any bond to aluminum that would cause anything
more than inconvenience if it failed. Heat and humidity seem to be the
culprits, which might explain why some people report long lasting bonds
and others have failures.
Best,
Dennis
________________________________________________________________________________
| From: | "Vernon Little" <rv-9a-online(at)telus.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
Actually, what you are referring to is "skin effect" and it only comes into
play at high frequencies. For DC loads in an aircraft, it's the total
cross-sectional area that determines the resistance.
For what it's worth, Brass has about 4 times the resistance of Copper (7 vs.
1.7 microhm-centimeters according the Handbook of Chemistry and Physics).
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ralph
Finch
Sent: April 27, 2008 9:29 AM
Subject: RE: AeroElectric-List: Re: Copper Bar vs "FAT" wire
-->
I assume your motive for using a bar instead of wire is higher current
capacity -> lower resistance -> lower voltage drop and power loss.
I'm a hydraulic engineer for the California Dept. of Water Resources...and
years ago took a tour of our biggest lift station at the base of the
Tehachapi Mtns. A single lift of about 2,000 feet, 4,500 cfs pumping rate.
That requires a lot of power. I remember well the "wire" they use to carry
the current (which I think was about 1000 amps at 10-12kV): a tube a few
inches in diameter. The electrical engineer said current is carried on the
surface and the tube gave them the surface they needed.
Not suggesting you use a tube, but maybe braided multi-strand wire is better
than a single bar?
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Henry
Trzeciakowski
Sent: Sunday, April 27, 2008 8:58 AM
Subject: AeroElectric-List: Re: Copper Bar vs "FAT" wire
-->
Bob:
I'm planning to use copper bar in lieu of "fat wire" in 2 areas:
1- from the Starter Contactor to Master Battery Contactor - 1/8" (.125)
thick
2- and from the Starter Contactor to the 60 amp Current Limiter - 1/16"
(.063)...
My question is: Is the thickness of the copper bar appropriate?
Thanks
Hank
________________________________________________________________________________
| Subject: | Re: Copper Bar vs "FAT" wire |
I did the same thing. Van's recommends sandwiching (2) .063 strips, so
hopefully (1) .128 strip oughta be the same. I was using the same
thickness from master to starter to anl-60a to shunt, but it might be
worth a redo to change over to .063 between the starter, anl and shunt.
Here's my fwf wiring. The odd angle of the anl install was chosen to
keep the bolts accessible around the engine mount. Shaping the strip
was easy with a vice grip and hand seamer.
http://donka.net/gallery/view_photo.php?set_albumName=rv7wiring&id=DSC07591
Using the copper bar for these short runs was easier than fab'ing
cables at the time. I'm interested in feedback as well.
Don
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Epoxy to Aluminum |
Dennis Johnson wrote:
> Greetings,
>
> As part of building a composite airplane, I studied everything I could
> find about epoxies, materials, and adhesive bonding in general. I
> concluded that I did not have the ability to make an epoxy bond to
> aluminum that I could be confident that it wouldn't fail.
>
> The problem is that aluminum begins oxidizing immediately after
> cleaning. No matter how quick you are, unless you use
> extraordinary measures, there will be aluminum oxide on the surface
> you are bonding. Aluminum oxide has relatively low strength. The
> epoxy bonds well to the aluminum oxide, but the aluminum oxide isn't
> stuck very well to the underlying aluminum. After some number of
> hot/cold and wet/dry cycles, the bond may weaken enough to fail.
>
> Obviously, Boeing and others solved this problem long ago. However,
> based on the great reference book, "/Composite Basics/," by Andrew
> Marshall, their methods aren't practical for most of us homebuilders.
> From chapter 11, Marshall says, "Unfortunately, both the FPL etch and
> the PAA treatments (the ones widely and successfully used in the
> industry) involve extensive chemical control and a large investment in
> equipment."
>
> As an interesting aside, he describes an industry standard "wedge"
> test where two .125" thick aluminum pieces are bonded together. After
> curing, a wedge is driven into the end of the assembly, between the
> two pieces of aluminum, which forces the bond to break at that point.
> A mark is placed at the point where the fracture stops. The test
> piece is then placed into a warm, wet chamber for one hour. The
> assembly is then removed and the additional distance the crack
> propagated during the warm/wet test is measured. If the crack grew
> less than three-fourths of an inch, the bond is considered to be good
> for life. Marshall says that if the aluminum was cleaned but not
> chemically treated, the assembly will likely totally delaminate during
> the one hour test!
>
> Since I didn't have the ability to duplicate Boeing's chemical
> treatment process, I didn't make any bond to aluminum that would cause
> anything more than inconvenience if it failed. Heat and humidity seem
> to be the culprits, which might explain why some people report long
> lasting bonds and others have failures.
>
> Best,
> Dennis
When was the book written? There are some pretty impressive bonding
agents available now (not all are 'epoxy').
Even if you limit the discussion to epoxies, consider JB Weld. There are
*lots* of aluminum things flying around on homebuilts that were repaired
(or assembled) using JB Weld, including engine components.
The BD-4's original assembly method for the wing was to bond the
fiberglass wing ribs to the aluminum tube spar. Just about every one of
them leaked fuel through the poor quality 'glass rib/skin assemblies,
but I've never heard of a debonding event at the rib/spar joints. Note
that this joint was glued with what amounts to fuel sealant (commonly
called 'pro-seal'), not a true epoxy adhesive. It wasn't even designed
to be a structural adhesive.
FWIW,
Charlie
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Mechanical question |
4/27/2008
Hello Stan, Take a look at Perforated Base Binding Nuts and Studs on page
3120 of the
http://www.mcmaster.com/
online catalog as alternatives to both Click Bond and EZ-Point hardware.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
--------------------------------------------------------
From: Speedy11(at)aol.com
Subject: AeroElectric-List: Re: Mechanical question
Besides the aggravation of having to register to view their products, I
find
their products not suitable for aviation. I have used their nutplates and
ty wrap anchors and found both to be unsuitable for use in my airplane.
Their
adhesive does not adhere well. For example, of the nutplates I installed
(about 40), half came loose. Perhaps I didn't do a good job of applying
the
adhesive, but I doubt I would have screwed up 20 of them. The reasons I
don't
like using Click-Bond nutplates is because:
1. Nutplates are typically used in locations that are otherwise difficult
to
access. When the nutplate comes unglued (it's a matter of time) you cannot
remove the screw to replace it because the nutplate spins with the screw.
The nutplates are shorter than normal riveted nutplates and thus they can
spin
in a small space. If the nutplate location is not accessable, you have to
cut through panels to get to it.
2. If (when) a nutplate comes loose and frees itself from the screw (or
falls off while removing a screw), it can become FOD inside the airplane to
get
jammed in (you name it) controls, cables, etc.
Ask me how I've learned these things.
Personally, I threw away my $100 worth of Click-Bond products. I didn't
give them to anyone because I didn't want anyone else to suffer the same
aggravations and fears I did. I use only normal nutplates or screws with
nuts.
Perhaps others have had better results with Click-Bond, but I am not
satisfied with them and cannot recommend them.
Stan Sutterfield
________________________________________________________________________________
| From: | "raymondj" <raymondj(at)frontiernet.net> |
| Subject: | Re: Epoxy to Aluminum |
Greetings,
The following is intended for hardware mounting on boats.
After proper dry preparation per the manual, West System epoxy technical
manual ( catalogue number 002-950, 1994) on page 9, item 5, in bonding
hardware ( continued from page 8) says: "Coat the bottom contact surface of
the hardware with unthickened epoxy.Wire brush or sand the wet epoxy into
the surface with 50 grit sandpaper. Sanding the base with, coated with
epoxy, will expose the epoxy directly to fresh metal with no chance for the
metal to oxidize."
Raymond Julian
Kettle River, MN
"Hope for the best,
but prepare for the worst."
----- Original Message -----
From: "Dennis Johnson" <pinetownd(at)volcano.net>
Sent: Sunday, April 27, 2008 12:06 PM
Subject: AeroElectric-List: Epoxy to Aluminum
Greetings,
As part of building a composite airplane, I studied everything I could find
about epoxies, materials, and adhesive bonding in general. I concluded that
I did not have the ability to make an epoxy bond to aluminum that I could be
confident that it wouldn't fail.
The problem is that aluminum begins oxidizing immediately after cleaning.
No matter how quick you are, unless you use extraordinary measures, there
will be aluminum oxide on the surface you are bonding. Aluminum oxide has
relatively low strength. The epoxy bonds well to the aluminum oxide, but
the aluminum oxide isn't stuck very well to the underlying aluminum. After
some number of hot/cold and wet/dry cycles, the bond may weaken enough to
fail.
Obviously, Boeing and others solved this problem long ago. However, based
on the great reference book, "Composite Basics," by Andrew Marshall, their
methods aren't practical for most of us homebuilders. >From chapter 11,
Marshall says, "Unfortunately, both the FPL etch and the PAA treatments (the
ones widely and successfully used in the industry) involve extensive
chemical control and a large investment in equipment."
As an interesting aside, he describes an industry standard "wedge" test
where two .125" thick aluminum pieces are bonded together. After curing, a
wedge is driven into the end of the assembly, between the two pieces of
aluminum, which forces the bond to break at that point. A mark is placed at
the point where the fracture stops. The test piece is then placed into a
warm, wet chamber for one hour. The assembly is then removed and the
additional distance the crack propagated during the warm/wet test is
measured. If the crack grew less than three-fourths of an inch, the bond is
considered to be good for life. Marshall says that if the aluminum was
cleaned but not chemically treated, the assembly will likely totally
delaminate during the one hour test!
Since I didn't have the ability to duplicate Boeing's chemical treatment
process, I didn't make any bond to aluminum that would cause anything more
than inconvenience if it failed. Heat and humidity seem to be the culprits,
which might explain why some people report long lasting bonds and others
have failures.
Best,
Dennis
--------------------------------------------------------------------------------
Checked by AVG.
3:01 PM
________________________________________________________________________________
| From: | "Peter Pengilly" <peter(at)sportingaero.com> |
| Subject: | Strange Exp-Bus Problem |
Hi,
The last few times I have flown I have had a few strange 'brown-outs'.
It is most noticeable over the intercom as a short kind of shhuukkk
sound. Occasionally the radio (KX-135A) re-cycles and goes through its
re-boot routine. Initially I thought it was the master solenoid, but
thinking some more, I concluded that if the master solenoid were to
momentarily lose contact then the alternator would hold everything up.
The interrupts are usually of very short duration, such that I don't
notice most of the services blink, or by the time I have looked inside
everything is back on again. Sometimes it happens once every 5 or 10
minutes, sometimes not for a half hour or more.
I have an Exp-Bus DC load centre - I know that there has been some less
than complementary comments here about these devices (and I would not
fit one to an airplane I built, but I bought this one and I don't want
to rip it out). I'm now thinking that I am suffering some strange very
intermittent failure of this device (that I can't reproduce on the
ground).
Does anyone have any experience of the Exp-bus, or could suggest what
the fault might be?
Regards, Peter
________________________________________________________________________________
| From: | "RALPH HOOVER" <hooverra(at)verizon.net> |
| Subject: | Strange Exp-Bus Problem |
Peter,
This is just a shot in the dark as I have no experience with the EXP
buss. I do have considerable experience with failed solder joints on PC
boards used in automotive applications. Look carefully at the solder joints
for a fracture either through the solder or at the junction of the solder
and heavy objects like relays. A magnifying glass helps.
PS if this doesn't help on the EXP Buss keep it in mind for Bosch relays as
used on Volvo, Saab and many others. 10 minutes may save you enough to fill
a gas tank twice:) I've fixed flakey auto instrument panels this way also
and that's way more than a couple tanks of gas!!
Ralph & Laura Hoover
RV7A N527LR
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Peter
Pengilly
Sent: Sunday, April 27, 2008 4:30 PM
Subject: AeroElectric-List: Strange Exp-Bus Problem
Hi,
The last few times I have flown I have had a few strange 'brown-outs'.
It is most noticeable over the intercom as a short kind of shhuukkk
sound. Occasionally the radio (KX-135A) re-cycles and goes through its
re-boot routine. Initially I thought it was the master solenoid, but
thinking some more, I concluded that if the master solenoid were to
momentarily lose contact then the alternator would hold everything up.
The interrupts are usually of very short duration, such that I don't
notice most of the services blink, or by the time I have looked inside
everything is back on again. Sometimes it happens once every 5 or 10
minutes, sometimes not for a half hour or more.
I have an Exp-Bus DC load centre - I know that there has been some less
than complementary comments here about these devices (and I would not
fit one to an airplane I built, but I bought this one and I don't want
to rip it out). I'm now thinking that I am suffering some strange very
intermittent failure of this device (that I can't reproduce on the
ground).
Does anyone have any experience of the Exp-bus, or could suggest what
the fault might be?
Regards, Peter
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
>
>
>Bob:
>
>I already have the copper bars and, if fact, they are cut and ready to bend
>and install......they were a lottle hard to work with !!!!
>
>I'm somewhat surprised that you suggest .032: isn't that a little thin,
>considering these bars are replacing 4awg wire ????
Yeah . . . I stuck my foot in it. I was tangled up
in some numbers recalled from a different case
and blew it.
For COPPER thin sheet conductors, the resistance is
Micro-ohms/inch = .69/(t * w)
where t = thickness in inches and w = width in
inches.
So a copper bus bar .75" wide by .062" thick is on
the order of 15 micro-ohms/inch and from the big bus
bar tables in the sky at:
http://www.stormcopper.com/design/ampacity.htm
will exhibit a 30C rise at 145 amps. A strap
with 3" of length between studs would have a
resistance of about 45 micro-ohms. A 250 average
amps cranking current would drop 250 x 45
11,250 microvolts or 11.2 millivolts. Power
lost in this jumper would be .0112v * 250A
2.8 watts. If you had a 250 amp, 50mV shunt
in series with the starter for the purpose of
measuring its current draw, it would toss off
4x the voltage at 12.5 watts!
Note also that the same .062" x .75" strap
has a cross section of 0.046 square inches.
The minor diameter of a 5/16 stud is on the
order of 0.25" for a cross section of 0.049
square inches. So a 0.062 x .75 strap is
equivalent to the contactor studs it
attaches to.
In practice, this short bus will benefit from
heat-sinking by the mounting studs and
from relatively short duty cycle so you won't
experience the calculated 30C rise that can be
expected in long conductors allowed to achieve
a stabilized temperature.
As another Lister pointed out, brass has a higher
resistance than copper. A quick measurement of
some stuff in my metals bin from K&S Engineering
shows their brass alloy to be about 4x the
resistance of equivalent copper sheet. So, the
same stud-to-stud strap of .062 x .75 brass strip
would drop about 45 millivolts . . . on the same
order as a shunt . . . but unnecessarily high.
When I get the drive stand running, I'll be
strapping some high current contactors in the same
manner as those on your airplanes and I'll get some
actual drops and temperature rises for the various
materials available to us. In the mean time,
the K&S metals 16142 0.060 copper sheet is the
better material from which to fabricate stud
jumpers than the brass strip cited earlier.
Bob . . .
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Epoxy to Aluminum |
4/28/2008
Hello Dennis, Thanks for your interesting input.
One technique that may be used, if appropriate to the situation, to improve
joint holding, is to make holes in the aluminum. This permits the epoxy to
ooze through and form sort of a rivet effect for the glue line.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
-----------------------------------------------------------
From: "Dennis Johnson" <pinetownd(at)volcano.net>
Subject: AeroElectric-List: Epoxy to Aluminum
Greetings,
As part of building a composite airplane, I studied everything I could
find about epoxies, materials, and adhesive bonding in general. I
concluded that I did not have the ability to make an epoxy bond to
aluminum that I could be confident that it wouldn't fail.
The problem is that aluminum begins oxidizing immediately after
cleaning. No matter how quick you are, unless you use extraordinary
measures, there will be aluminum oxide on the surface you are bonding.
Aluminum oxide has relatively low strength. The epoxy bonds well to the
aluminum oxide, but the aluminum oxide isn't stuck very well to the
underlying aluminum. After some number of hot/cold and wet/dry cycles,
the bond may weaken enough to fail.
Obviously, Boeing and others solved this problem long ago. However,
based on the great reference book, "Composite Basics," by Andrew
Marshall, their methods aren't practical for most of us homebuilders.
>From chapter 11, Marshall says, "Unfortunately, both the FPL etch and
the PAA treatments (the ones widely and successfully used in the
industry) involve extensive chemical control and a large investment in
equipment."
As an interesting aside, he describes an industry standard "wedge" test
where two .125" thick aluminum pieces are bonded together. After
curing, a wedge is driven into the end of the assembly, between the two
pieces of aluminum, which forces the bond to break at that point. A
mark is placed at the point where the fracture stops. The test piece is
then placed into a warm, wet chamber for one hour. The assembly is then
removed and the additional distance the crack propagated during the
warm/wet test is measured. If the crack grew less than three-fourths of
an inch, the bond is considered to be good for life. Marshall says that
if the aluminum was cleaned but not chemically treated, the assembly
will likely totally delaminate during the one hour test!
Since I didn't have the ability to duplicate Boeing's chemical treatment
process, I didn't make any bond to aluminum that would cause anything
more than inconvenience if it failed. Heat and humidity seem to be the
culprits, which might explain why some people report long lasting bonds
and others have failures.
Best,
Dennis
________________________________________________________________________________
| Subject: | Re: Copper Bar vs "FAT" wire |
| From: | "grjtucson" <george(at)georgejenson.com> |
nuckolls.bob(at)cox.net wrote:
>
> Yeah . . . I stuck my foot in it. I was tangled up
> in some numbers recalled from a different case
> and blew it.
>
>
> As another Lister pointed out, brass has a higher
> resistance than copper. A quick measurement of
> some stuff in my metals bin from K&S Engineering
> shows their brass alloy to be about 4x the
> resistance of equivalent copper sheet. So, the
> same stud-to-stud strap of .062 x .75 brass strip
> would drop about 45 millivolts . . . on the same
> order as a shunt . . . but unnecessarily high.
>
> When I get the drive stand running, I'll be
> strapping some high current contactors in the same
> manner as those on your airplanes and I'll get some
> actual drops and temperature rises for the various
> materials available to us. In the mean time,
> the K&S metals 16142 0.060 copper sheet is the
> better material from which to fabricate stud
> jumpers than the brass strip cited earlier.
>
> Bob . . .
Ouch.
Bob,
Per your earlier recommendation to me, I standardized on 4 awg fat wires for my
60amp RV-7 and I went with .75 x .062 brass for the strap between master and
starter contactor and between starter contactor and anl. You had actually suggested
.032 but that seemed thin to me, particularly since Van's calls out .125
copper.
Now you're suggesting copper for these and I'm wondering if I should swap out my
brass? It's not a huge amount of work but if the .062 brass will still work
fine, I'm likely to leave it.
Also, is .032 brass still OK for the ground buses? I haven't installed those yet
though the tabs are soldered on.
Thanks,
George Jenson
RV-7
Tucson, AZ
--------
George Jenson -
Tucson, AZ - RV-7 Standard Build
Empennage Completed 1/06
Wings Completed 11/06
Fuselage in Progress
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=179827#179827
________________________________________________________________________________
| Subject: | Re: Epoxy to Aluminum |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
> Greetings,
>
> After proper dry preparation per the manual, West System epoxy technical manual
(catalogue number 002-950, 1994) on page 9, item 5, in bonding hardware ( continued
from page says: "Coat the bottom contact surface of the hardware with
unthickened epoxy. Wire brush or sand the wet epoxy into the surface with 50
grit sandpaper. Sanding the base with, coated with epoxy, will expose the epoxy
directly to fresh metal with no chance for the metal to oxidize."
> Raymond Julian
> Kettle River, MN
The West System method seems brilliant to me. It seems to use the approach often
used in soldering aluminum where a stainless-wire brush removes the oxide while
being protected from re-oxidation by the solder (and flux). Nice.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=179832#179832
________________________________________________________________________________
| Subject: | Re: Mechanical question - Bond Studs |
| From: | <rparigor(at)SUFFOLK.LIB.NY.US> |
"Perforated Base Binding Nuts and Studs on page 3120 of the
http://www.mcmaster.com"
For what its worth I have used McMaster perforated base studs. I used the
Stainless ones. They are very shiny, guess you could hand sand them,
blasting with aluminium oxide does a better job. I used the 1/4-20 studs,
but needed small nuts so tapped some aviation small outside diameter nuts
and gave them a bit of a squishing, and used a dab of Loctite. They are
easy to cut, and in my instance tack weld together (TIG) for easy
installation with exact dimension between studs for holding two Flowscan
201B transducers.
They are heavier than Aircraft Spruce aluminium studs, but the ability to
weld made them my choice for the Transducers.
As far as bonding to aluminium, you can not do much better than Redux 420
(or Huntsmans Epibond 420) which has rubber added to it, also has glass in
its brew so you can not squeeze out all adhesive. My Europa is held
together with this stuff! Far superior to Laminating Epoxy or JB Weld.
Scuff sand with 80 grit or if scratches will not cause stress cracking use
40 grit. Then wet out with pure Redux, then make a bed of Redux and Flox
(toothpaste consistency, Flox is chopped cotton and makes structural mix)
and set stud in place. Aluminium studs from Spruce or Wicks work great
with Redux, I drill some holes in it for rivet effect. Note McMaster studs
allow a flat base even with adhesive because of integral stand off. If it
is something I don't want to come off ever, can put 2 BID on it. BID is
BiDirectional fiberglass cloth as used by Rutan. What you do is take a
piece of clear plastic and draw a circle on it with a magic marker, turn
sheet over and place 2 pieces of BID on it, then wet out with Redux and
squeegee out excess, make a hole in center for stud, cut circumferance and
apply to stud, then peel off plastic.
Again Redux has rubber in it, so it is somewhat flexible, it prevents
point loading and peeling. Boeing uses Epibond 420. I am pretty certain
that if you anodized it would probably make a better bond, but I am pretty
certain that studs stuck only with Redux to scuffed aluminium will be
around for life of aircraft, and with 2 BID, foreverrrrr.
Side note, I bond zip tie blocks or other nylon hold downs to aluminium,
by scuffing nylon with 40 and aluminium with 40 or 80, then JB KWIK in
place, after 15 minutes Redux/Flox fillet and 1 Redux/BID. If you don't
have Redux, you could probably plastic sheet 1 BID with long cure JB Weld.
If you don't have BID could probably plastic sheet a few layers of gauze
style Spackle tape with long cure JB Weld, both of which are available at
the aviation isle of Home Depot or your local home center or hardware
store. Test first as I have not, but pretty certain it will be a winner.
On Fiberglass, I JB KWIK, then Aeropoxy/flox fillet then 1 Aeropoxy/BID.
Redux would work but harder to work with (mix and mess and expense).
Back to studs, you will need to try, but on aluminium or fiberglass, scuff
stud with 40 grit, and aircraft with 40 or 80, wet stud and aircraft with
thin layer of JB long cure, then mix some JB long cure with some flox
(toothpaste consistency) and install stud, then plastic sheet a few layers
of spackle tape and JB long cure, cut center hole and scissor OD and
install.
If cold, or damp just leave the plastic on and remove after cure, will be
a nice smooth surface.
If you are not working in 70 plus temperatures with less than ~60%
humidity, warm up stud and airplane.
Warm up first, scuff sand and apply adhesive, wait as Little time as you
can after scuff to apply adhesive.
Ron Parigoris
I could have installed 4 studs with JB Long and Spackle tape in the amount
of time it took me to write this.
________________________________________________________________________________
| From: | "Henry Trzeciakowski" <hammer408(at)comcast.net> |
| Subject: | Fuses vs Circuit Breaker Fuses |
Bob:
I was "surfing the net" the other day and came upon a couple of sites that
sell ATC Circuit Breaker fuses. They fit a standard fluse block that B & C
sells. I found these quite interesting and pondered the question:
if they are worth the investment (not a huge difference in cost between the
CB fuse and regular fuse)?
are they more robust and would they make a good substitute for fuselable
links?
and serve any "better" or improve upon the electric architecture than
standard fuses? - especially in your Z diagrams: Z-11, 12 and or 13?
Henry
________________________________________________________________________________
| From: | "Mark Doble" <mark(at)stratologic.net> |
| Subject: | Re: Strange Exp-Bus Problem |
Hey Peter,
Check the electrical system closely for wire connector rings of the
incorrect size. Eg. A too large ring over a connector stud.
If the connector rings are bigger than the stud, over time they vibrate and
the resulting residue makes a poor contact. This will give you the exact
fault you have.intermittent electrical faults.
I would check all the contactors connections, alternator connectors,
etc..anything with a big ring connector. The culprit ring connector will
look black when you take the nut off.
Don't ask how I know so much about this problem :-)
Cheers,
Mark.
________________________________________________________________________________
| Subject: | Re: Copper Bar vs "FAT" wire |
| From: | "n277dl" <dljinia(at)yahoo.com> |
grjtucson wrote:
>
> nuckolls.bob(at)cox.net wrote:
> >
> > Yeah . . . I stuck my foot in it. I was tangled up
> > in some numbers recalled from a different case
> > and blew it.
> >
> >
> > As another Lister pointed out, brass has a higher
> > resistance than copper. A quick measurement of
> > some stuff in my metals bin from K&S Engineering
> > shows their brass alloy to be about 4x the
> > resistance of equivalent copper sheet. So, the
> > same stud-to-stud strap of .062 x .75 brass strip
> > would drop about 45 millivolts . . . on the same
> > order as a shunt . . . but unnecessarily high.
> >
> > When I get the drive stand running, I'll be
> > strapping some high current contactors in the same
> > manner as those on your airplanes and I'll get some
> > actual drops and temperature rises for the various
> > materials available to us. In the mean time,
> > the K&S metals 16142 0.060 copper sheet is the
> > better material from which to fabricate stud
> > jumpers than the brass strip cited earlier.
> >
> > Bob . . .
>
>
> Ouch.
>
> Bob,
>
> Per your earlier recommendation to me, I standardized on 4 awg fat wires for
my 60amp RV-7 and I went with .75 x .062 brass for the strap between master and
starter contactor and between starter contactor and anl. You had actually suggested
.032 but that seemed thin to me, particularly since Van's calls out .125
copper.
>
> Now you're suggesting copper for these and I'm wondering if I should swap out
my brass? It's not a huge amount of work but if the .062 brass will still work
fine, I'm likely to leave it.
>
> Also, is .032 brass still OK for the ground buses? I haven't installed those
yet though the tabs are soldered on.
>
> Thanks,
>
> George Jenson
> RV-7
> Tucson, AZ
George,
I was doing the annual on my 7A this past weekend. It'd began to get difficult
to start the prop spinning when cold. The battery was only a couple years
old but I decided to replace it. Also, just for good measure I replaced the original
starter contactor and battery contactor with new ones from B&C, original
ones from Vans. Rumor (un-proven by me) that the B&C were better quality.
Anyway, had to replace the copper bus bars as the original doesn't work anymore.
Couldn't find copper anywhere local so came back, found the post in early April
where brass was recommended instead of copper.... purchased .063 x .5, installed
on the 7A and it all worked fine. Only a couple starts but didn't have
any problems so the brass will work. Guess time will tell how well.
Doug
--------
Doug
"Fools" are always more creative than process people and will always
find ways to ruin a perfectly good set of processes.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=179943#179943
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Mechanical question - Bond Studs |
>
>
>I found that copper tubing used for gas lines can be beaten flat and used
>as the copper bar - the advantage is you can find it almost anywhere.
>
>Ed
If one is attempting to get gas-tight connections to
the sheet-material bus-bars, they need to be as flat
as possible with parallel and smooth front and back
surfaces. While you can certainly drill holes in and
bolt up chunks of flattened tubing, the finished product
leaves some concerns for long-term joint integrity.
Suggest you stick with manufactured sheet materials.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
>
> > Bob,
> >
> > Per your earlier recommendation to me, I standardized on 4 awg fat
> wires for my 60amp RV-7 and I went with .75 x .062 brass for the strap
> between master and starter contactor and between starter contactor and
> anl. You had actually suggested .032 but that seemed thin to me,
> particularly since Van's calls out .125 copper.
> >
> > Now you're suggesting copper for these and I'm wondering if I should
> swap out my brass? It's not a huge amount of work but if the .062 brass
> will still work fine, I'm likely to leave it.
> >
> > Also, is .032 brass still OK for the ground buses? I haven't installed
> those yet though the tabs are soldered on.
> >
> > Thanks,
> >
> > George Jenson
> > RV-7
> > Tucson, AZ
>
>
>George,
> I was doing the annual on my 7A this past weekend. It'd began to get
> difficult to start the prop spinning when cold. The battery was only a
> couple years old but I decided to replace it. Also, just for good
> measure I replaced the original starter contactor and battery contactor
> with new ones from B&C, original ones from Vans. Rumor (un-proven by me)
> that the B&C were better quality.
>
>Anyway, had to replace the copper bus bars as the original doesn't work
>anymore. Couldn't find copper anywhere local so came back, found the post
>in early April where brass was recommended instead of copper.... purchased
>.063 x .5, installed on the 7A and it all worked fine. Only a couple
>starts but didn't have any problems so the brass will work. Guess time
>will tell how well.
I think you're going to be okay. It will warm up some
during cranking. I'll know more about the details later
this year. Weather is warming up - spent several good
chunks of time in the shop cleaning up around the drive
stand. My son is going to strip out all the old system
wiring next weekend in anticipation of installing a mock-up
of Z-11/13-8/14 electrical systems.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Fuses vs Circuit Breaker Fuses |
>
>
>Bob:
>
>I was "surfing the net" the other day and came upon a couple of sites that
>sell ATC Circuit Breaker fuses. They fit a standard fluse block that B & C
>sells. I found these quite interesting and pondered the question:
>
> if they are worth the investment (not a huge difference in cost between the
>CB fuse and regular fuse)?
>
>are they more robust and would they make a good substitute for fuselable
>links?
>
>and serve any "better" or improve upon the electric architecture than
>standard fuses? - especially in your Z diagrams: Z-11, 12 and or 13?
You can't get any simpler/more-reliable protection than the
fuse. Breakers add moving parts in a device that will probably
never be called upon to protect a wire but . . .
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
| Subject: | Re: Mechanical question |
Considering how many people have had success with them, the fault obviously
lies with me.
I was adhering to bare aluminum.
I have already switched to all normal riveted nutplates and I'm very happy
with them.
Stan Sutterfield
I add my data point on them. Not to be contrary, but I have never had one
come off and indeed when I have misplaced one I found it very difficult to
remove. I wonder Stan, what kind of surface you were adhering to? Boeing,
Lockheed and Airbus use them, can't be all that bad.
Tim Andres
**************Need a new ride? Check out the largest site for U.S. used car
listings at AOL Autos.
(http://autos.aol.com/used?NCID=aolcmp00300000002851)
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
>
>
>grjtucson wrote:
> >
> > nuckolls.bob(at)cox.net wrote:
> > >
> > > Yeah . . . I stuck my foot in it. I was tangled up
> > > in some numbers recalled from a different case
> > > and blew it.
> > >
> > >
> > > As another Lister pointed out, brass has a higher
> > > resistance than copper. A quick measurement of
> > > some stuff in my metals bin from K&S Engineering
> > > shows their brass alloy to be about 4x the
> > > resistance of equivalent copper sheet. So, the
> > > same stud-to-stud strap of .062 x .75 brass strip
> > > would drop about 45 millivolts . . . on the same
> > > order as a shunt . . . but unnecessarily high.
> > >
> > > When I get the drive stand running, I'll be
> > > strapping some high current contactors in the same
> > > manner as those on your airplanes and I'll get some
> > > actual drops and temperature rises for the various
> > > materials available to us. In the mean time,
> > > the K&S metals 16142 0.060 copper sheet is the
> > > better material from which to fabricate stud
> > > jumpers than the brass strip cited earlier.
> > >
> > > Bob . . .
> >
> >
> > Ouch.
> >
> > Bob,
> >
> > Per your earlier recommendation to me, I standardized on 4 awg fat
> wires for my 60amp RV-7 and I went with .75 x .062 brass for the strap
> between master and starter contactor and between starter contactor and
> anl. You had actually suggested .032 but that seemed thin to me,
> particularly since Van's calls out .125 copper.
> >
> > Now you're suggesting copper for these and I'm wondering if I should
> swap out my brass? It's not a huge amount of work but if the .062 brass
> will still work fine, I'm likely to leave it.
> >
> > Also, is .032 brass still OK for the ground buses? I haven't installed
> those yet though the tabs are soldered on.
> >
> > Thanks,
> >
> > George Jenson
> > RV-7
> > Tucson, AZ
>
>
>George,
> I was doing the annual on my 7A this past weekend. It'd began to get
> difficult to start the prop spinning when cold. The battery was only a
> couple years old but I decided to replace it. Also, just for good
> measure I replaced the original starter contactor and battery contactor
> with new ones from B&C, original ones from Vans. Rumor (un-proven by me)
> that the B&C were better quality.
Last time I had any specific information on Van's contactors
he was selling Cole-Hersey battery contactors. I think his
starter contactors were commercial-off-the-shelf devices too.
These are in the same league as the devices offered by B&C.
I'd be interested in hearing from any folks who are having
difficulties with devices from either source.
>Anyway, had to replace the copper bus bars as the original doesn't work
>anymore. Couldn't find copper anywhere local so came back, found the post
>in early April where brass was recommended instead of copper.... purchased
>.063 x .5, installed on the 7A and it all worked fine. Only a couple
>starts but didn't have any problems so the brass will work. Guess time
>will tell how well.
Hmmm . . . . 0.5" wide? After you drill a 5/16" hole in
this for attachment to contactor, you're short on edge
margin. 0.75" wide is recommended both for mechanical
and electrical considerations.
I'll be looking into voltage drop and temperature
rise issues for these short stud-to-stud jumpers
later this year.
Bob . . .
________________________________________________________________________________
| From: | Gerard Ricciotti <gfr56(at)comcast.net> |
Greetings
Refering to the Fig Z-13/8 and the wiring of the Endurance bus the
connection from the Main bus is not protected with a fuse or breaker
yet the feed from the battery bus is protected with a fuse at the bus
block and a fuse link between the e-bus alternate feed switch and the
endurance bus, what is the concept behind this?
Also on the same figure Z-13/8 the connection between the DC Power
Master Switch and the Main Power Distribution Bus has both a breaker
and a fuse link, what is concept behind this?
On the same diagram the wire gage for the connection between the Main
Power Distribution Bus and the Endurance Bus has an * denoting "6
inches or less" . In my installation the wire run will be longer than
six inches. Do I need to use a larger gage wire?
Thanks in advance Jerry
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Copper Bar vs "FAT" wire |
One reason I decided to use cable instead of bar is that when combined with
terminal boots, the cable is insulated against a variety of accidental
shorts (falling wires, tools, moisture, whatever) whether in operation or
maintenance.
Is there a good way to insulate bars?
Ron
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Hand-held antenna adapter |
>Below is the result of your inquiry. It was submitted by
>Hank Eilts (eilts(at)ti.com) on Tuesday, April 29, 2008 at 08:14:03
>---------------------------------------------------------------------------
>
>Tuesday, April 29, 2008
>
>Comments/Questions: Hello Bob,
>
>I believe that I saw an article on your website describing how to wire a
>jack into the panel for connecting a handheld comm to the external
>aircraft antenna. I believe you advocated a 1/4 phone jack with a
>switching function on the jack for the panel. However, now I cannot find
>the article and I wonder if you may have pulled the article due to
>operational problems with the technique.
Yes, the quality of close-circuit phone jacks available to
the task was pretty poor. Failure of the jack's switch
would disable the panel-mounted radio. Here's a photo
of the DIY project:
http://www.aeroelectric.com/Pictures/Antenna/CommTap-Jack.jpg
ICOM offers a hand-held adapter with the same technology
http://www.aeroelectric.com/Pictures/Antenna/ICOM_Hand_Held_Adapter_1.jpg
http://www.aeroelectric.com/Pictures/Antenna/ICOM_Hand_Held_Adapter_2.jpg
>I work in electronics and can wire up the panel mod without problems, but
>I'm wondering if normal panel vibration can make/break the switch when a
>handheld in not installed, causing problems for the main radio.
Given the lead lengths for the commercial off the shelf
device from ICOM, you probably couldn't do much worse!
How about CK7000 series switch with a bnc chassis
mount connector mounted right next to each other.
http://www.aeroelectric.com/Pictures/Switches/7301P3YZQE.jpg
Bring ship's antenna and transmitter coaxes up to
the back and assemble with shortest practical leads
to toggle antenna between hand-held and panel-mounted
transceivers.
In fact, I've been considering a product consisting
of a 2 pole switch that terminates the panel-mounted
radio into a dummy load when the hand-held is being
serviced by the antenna.
However you decide to go, I don't recommend the 1/8"
closed circuit jack.
Bob . . .
----------------------------------------
( IF one wishes to be "world class" at )
( anything, what ever you do must be )
( exercised EVERY day . . . )
( R. L. Nuckolls III )
----------------------------------------
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Epoxy to Aluminum |
> ... Perhaps the Click-Bond products are most ideal for composite
> airplanes and regular nutplates are better for aluminum airplanes.
>
FWIW, all my 200+ Click Bond fasteners are on aluminum. Surface prep is
essential, but easy. Just a scuff with the provided Scotch Brite pad, a
swipe with the provided solvent/cleaner, thoroughly mix the two part epoxy
from the pre-measured packet... and on they go. Wait 24 hrs. to cure and
bolts torque down fine.
Ron
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
>One reason I decided to use cable instead of bar is that when combined
>with terminal boots, the cable is insulated against a variety of
>accidental shorts (falling wires, tools, moisture, whatever) whether in
>operation or maintenance.
>
>Is there a good way to insulate bars?
Not that I know of. There are 'partial' fixes
for being bare . . . but most folks don't worry
about it. See pictures at:
http://www.aeroelectric.com/Pictures/Wiring_Technique/Contactor_Interconnect/
Note these two in particular . . .
http://www.aeroelectric.com/Pictures/Wiring_Technique/Contactor_Interconnect/Contactor_Strap_3.jpg
http://www.aeroelectric.com/Pictures/Wiring_Technique/Contactor_Interconnect/Contactor_Strap_4.jpg
which I took on the production line. There's
lots of electrically hot stuff hanging out in
the breeze . . . but each risk has been evaluated
against probability of problems and deemed
good to go.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: z13/8 question |
>
>Greetings
> Refering to the Fig Z-13/8 and the wiring of the Endurance bus the
>connection from the Main bus is not protected with a fuse or breaker
>yet the feed from the battery bus is protected with a fuse at the bus
>block and a fuse link between the e-bus alternate feed switch and the
>endurance bus, what is the concept behind this?
Note the (*) symbol on short feeders which if kept
down to 6" or so, are not generally considered worthy
of protection. If the main and e-bus fuse blocks are
co-located with the normal feedpath diode, then protection
can be dispensed with.
>Also on the same figure Z-13/8 the connection between the DC Power
>Master Switch and the Main Power Distribution Bus has both a breaker
>and a fuse link, what is concept behind this?
The wire from the bus to the alternator field breaker is an
EXTENSION of the bus . . . which is also a long wire and
generally worthy of some protection. However, if you use
crowbar ov protection, the fusing-constant for the upstream
protection needs to be much longer than the fusing constant
for the crow-bar breaker. Hence, the fusible link which will
carry enough current to crow-bar the breaker without
opening itself.
>On the same diagram the wire gage for the connection between the Main
>Power Distribution Bus and the Endurance Bus has an * denoting "6
>inches or less" . In my installation the wire run will be longer than
>six inches. Do I need to use a larger gage wire?
The "six-inch-rule" is a wiring practice adopted by the
certificated aircraft world for the purpose of deciding
whether or not fault protection is needed. It's up to
you if you want to adopt a "12-inch-rule" . . . or whatever.
It's not a wire size issue.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Generally accepted wiring practices |
>
>Question: When attaching fast-on connectors to wire, is it generally
>good to heat shrink every connector?
I don't think so. Closing things up without making
it a hermetic seal only encourages entrapment of moisture.
>Is there a standard for when I
>should use heat-shrink and when I can ignore it? I understand the value
>of labeling, but that is irrelevant for this question.
None I've seen. I leave them hanging out in the breeze
to get dry fast if ever subjected to drip, splash or
condensation. I've never seen anyone cover them in
a production environment either but it's a low-risk
concern . . . so if you like a more "finished" look,
it will probably be just fine.
> In practice I have also used liquid electrical tape to backfill
>open connectors. It appears that has the same effect of keeping dirt
>out, but may not have the tensile strength required if the squirrels get
>busy.
??? If you have PIDG style terminals attached with the appropriate
tool, no further processing is needed.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| Subject: | Re: Copper Bar vs "FAT" wire |
| From: | "n277dl" <dljinia(at)yahoo.com> |
nuckolls.bob(at)cox.net wrote:
>
>
>
>
> >
> >
> >
> >
> >
> >
> > George,
> >
> > I was doing the annual on my 7A this past weekend. It'd began to get
> > difficult to start the prop spinning when cold. The battery was only a couple
years old but I decided to replace it. Also, just for good measure I replaced
the original starter contactor and battery contactor with new ones from
B&C, original ones from Vans. Rumor (un-proven by
> > me) that the B&C were better quality.
> >
> >
> >
> >
>
>
> Last time I had any specific information on Van's contactors he was selling
Cole-Hersey battery contactors. I think his starter contactors were commercial-off-the-shelf
devices too. These are in the same league as the devices offered
by B&C. I'd be interested in hearing from any folks who are having
difficulties with devices from either source.
>
>
>
>
>
>
> > Anyway, had to replace the copper bus bars as the original doesn't work anymore.
Couldn't find copper anywhere local so came back, found the post in early
April where brass was recommended instead of copper....
> > purchased .063 x .5, installed on the 7A and it all worked fine. Only a couple
starts but didn't have any problems so the brass will work. Guess time will
tell how well.
> >
> >
> >
> >
>
>
> Hmmm . . . . 0.5" wide? After you drill a 5/16" hole in this for attachment
to contactor, you're short on edge margin. 0.75" wide is recommended both
for mechanical and electrical considerations.
>
>
>
> I'll be looking into voltage drop and temperature rise issues for these short
stud-to-stud jumpers later this year.
>
> Bob . . .
Bob, thanks for the correction with 3/4 inch wide. I picked up the .5
from the original design using copper from Vans and your response on
4/7/08 to George. I'll switch it out to 3/4 copper at some point.
>
>
>
>
> nuckolls.bob(at)cox.net wrote:
>
> Quote:
>
>
> Summary - 5 questions:
>
> 1. 2AWG welding cable OK for engine to firewall ground in lieu of braid?
>
> 2. 2AWG welding cable OK for 60amp PP alternator b-lead or should I downsize?
>
> Go 4AWG throughout . . .
> Quote:
>
> 3. .125 x .5 brass bar OK for contactor to contactor run (Van's specs same size
but Copper)?
>
> 4. .063 x .5 brass bar OK for contactor to current limiter (no starter
>
> current)?
>
> 5. .050 x .75 x 5 copper bars/straps on either side of firewall, each
>
> soldered with brass tabs, with 3/16 brass bolts as ground setup OK?
>
>
>
>
>
>
>
> Go .032 brass for all and at LEAST 5/16 or better
>
> yet 3/8" brass bolts for fat-wire terminals. Torque
>
> to 80+ percent of maximum for the materials and thread
>
> sizes. Check AC43.13 for values.
>
>
>
>
>
> Fantastic Bob, thanks for the help and for the work you continue to do.
> Simply extraordinary.
>
> George
>
>
Also, let me be clear that I did not test the contactors but instead
took the shotgun approach. The battery contactor is in fact a
Cole-Hersey so do not want to mis-represent it's quality.
I replaced the starter contactor as well for good measure :)
Got to quit reading so much.
Doug
--------
Doug
"Fools" are always more creative than process people and will always
find ways to ruin a perfectly good set of processes.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=180182#180182
Attachments:
http://forums.matronics.com//files/strtcntr_159.jpg
________________________________________________________________________________
| From: | "Dave Leikam" <daveleikam(at)wi.rr.com> |
Is it necessary to purchase expensive comant antenna's or are less
expensive bent whip belly mounts as good?
Dave Leikam
RV-10
Ready to install some antennas
________________________________________________________________________________
| From: | "Dale Ensing" <densing(at)carolina.rr.com> |
| Subject: | Re: Antenna choice |
My research when I purchased was to spend the money and get a good one.
Have a Comant and not sorry.
Dale
----- Original Message -----
From: Dave Leikam
To: aeroelectric-list(at)matronics.com
Sent: Wednesday, April 30, 2008 12:08 AM
Subject: AeroElectric-List: Antenna choice
Is it necessary to purchase expensive comant antenna's or are less
expensive bent whip belly mounts as good?
Dave Leikam
RV-10
Ready to install some antennas
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
Since heat dissapation is not an issue for me, I just wrapped them in
silicone self sticking tape. It sticks to itself with no adhesive and
unlike electrical tape, it seems to last forever unless you cut it off.
Ken
Ron Shannon wrote:
> One reason I decided to use cable instead of bar is that when combined
> with terminal boots, the cable is insulated against a variety of
> accidental shorts (falling wires, tools, moisture, whatever) whether in
> operation or maintenance.
>
> Is there a good way to insulate bars?
>
> Ron
>
________________________________________________________________________________
| From: | "Jerry Ricciotti" <gfr56(at)comcast.net> |
| Subject: | Re: z13/8 question |
Many Thanks
Jerry
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
Sent: Tuesday, April 29, 2008 10:53 PM
Subject: Re: AeroElectric-List: z13/8 question
>
>
>
>>
>>
>>Greetings
>> Refering to the Fig Z-13/8 and the wiring of the Endurance bus the
>>connection from the Main bus is not protected with a fuse or breaker
>>yet the feed from the battery bus is protected with a fuse at the bus
>>block and a fuse link between the e-bus alternate feed switch and the
>>endurance bus, what is the concept behind this?
>
> Note the (*) symbol on short feeders which if kept
> down to 6" or so, are not generally considered worthy
> of protection. If the main and e-bus fuse blocks are
> co-located with the normal feedpath diode, then protection
> can be dispensed with.
>
>>Also on the same figure Z-13/8 the connection between the DC Power
>>Master Switch and the Main Power Distribution Bus has both a breaker
>>and a fuse link, what is concept behind this?
>
> The wire from the bus to the alternator field breaker is an
> EXTENSION of the bus . . . which is also a long wire and
> generally worthy of some protection. However, if you use
> crowbar ov protection, the fusing-constant for the upstream
> protection needs to be much longer than the fusing constant
> for the crow-bar breaker. Hence, the fusible link which will
> carry enough current to crow-bar the breaker without
> opening itself.
>
>>On the same diagram the wire gage for the connection between the Main
>>Power Distribution Bus and the Endurance Bus has an * denoting "6
>>inches or less" . In my installation the wire run will be longer than
>>six inches. Do I need to use a larger gage wire?
>
> The "six-inch-rule" is a wiring practice adopted by the
> certificated aircraft world for the purpose of deciding
> whether or not fault protection is needed. It's up to
> you if you want to adopt a "12-inch-rule" . . . or whatever.
> It's not a wire size issue.
>
> Bob . . .
>
> ----------------------------------------)
> ( . . . a long habit of not thinking )
> ( a thing wrong, gives it a superficial )
> ( appearance of being right . . . )
> ( )
> ( -Thomas Paine 1776- )
> ----------------------------------------
>
>
>
________________________________________________________________________________
| Subject: | Re: Copper Bar vs "FAT" wire |
| From: | Larry Mac Donald <lm4(at)juno.com> |
Yes. A liquid semi-hard rubber called Plastisol.
writes:
Is there a good way to insulate bars?
Ron
________________________________________________________________________________
| Subject: | Re: Epoxy to Aluminum |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
After following this thread it occurred to me that I had to learn ONE very important
thing when using epoxy particularly--there must be epoxy in the bonded interface...Duh....It
is easy to prepare the surfaces, put epoxy on one or both
parts and press or clamp the parts together squeezing out virtually ALL the epoxy.
Thus no bonded joint, or the bond has inadequate flexibility and fails.
Pay attention to the minimum bond-line specification, or failing that, if the joint
is between two very flat surfaces, assure that a few thousandths bond-line
remains.
"A witty saying proves nothing."
--Voltaire
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=180233#180233
________________________________________________________________________________
| From: | paul wilson <pwmac(at)sisna.com> |
| Subject: | Another fat wire lug connection |
Comments solicited
<http://fordfuelinjection.com/?p=59>http://fordfuelinjection.com/?p=59
The world of car battery connections. The link shows a popular way to
deal with soldering the big cables.
The last pic also shows his alt to batt cable with the fat fuse. Used
for high amp alts for the off road guys.
Paul
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
| Subject: | Re: Another fat wire lug connection |
paul wilson wrote:
> Comments solicited
> <http://fordfuelinjection.com/?p=59>http://fordfuelinjection.com/?p=59
>
> The world of car battery connections. The link shows a popular way to
> deal with soldering the big cables.
> The last pic also shows his alt to batt cable with the fat fuse. Used
> for high amp alts for the off road guys.
>
> Paul
Good-gawd!!!
The propane torch is WAY oversized for this job. It's like using a Mack
truck to race around a picnic table 8*)
Get one of the $8 butane torches. They're useful for all sorts of
things other than making fat cables, and you won't set the house on fire
doing it 8*)
________________________________________________________________________________
| Subject: | Generally accepted wiring practices |
Thanks Bob...
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Sent: Tuesday, April 29, 2008 10:58 PM
Subject: Re: AeroElectric-List: Generally accepted wiring practices
-->
>
>Question: When attaching fast-on connectors to wire, is it generally
>good to heat shrink every connector?
I don't think so. Closing things up without making
it a hermetic seal only encourages entrapment of moisture.
>Is there a standard for when I
>should use heat-shrink and when I can ignore it? I understand the value
>of labeling, but that is irrelevant for this question.
None I've seen. I leave them hanging out in the breeze
to get dry fast if ever subjected to drip, splash or
condensation. I've never seen anyone cover them in
a production environment either but it's a low-risk
concern . . . so if you like a more "finished" look,
it will probably be just fine.
> In practice I have also used liquid electrical tape to
>backfill open connectors. It appears that has the same effect of
>keeping dirt out, but may not have the tensile strength required if the
>squirrels get busy.
??? If you have PIDG style terminals attached with the appropriate
tool, no further processing is needed.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Emrath" <emrath(at)comcast.net> |
| Subject: | Re: Copper Bar vs "FAT" wire |
Ron, How about some large diameter shrink tubing?
Marty
From: "Ron Shannon" <rshannon(at)CRUZCOM.COM>
Subject: Re: AeroElectric-List: Re: Copper Bar vs "FAT" wire
One reason I decided to use cable instead of bar is that when combined with
terminal boots, the cable is insulated against a variety of accidental
shorts (falling wires, tools, moisture, whatever) whether in operation or
maintenance.
Is there a good way to insulate bars?
Ron
________________________________________________________________________________
| From: | "Europa (Alfred Buess)" <ykibuess(at)bluewin.ch> |
| Subject: | AW: New HOBBS Idea |
There is another clever solution for hooking up the Hobbs to your engine:
Comco Ikarus (http://www.comco-ikarus.de/index_english.html) sells an
electronic filter produced by Utz Schicke (producer of the Schicke GR6
regulator for Rotax engines) which hooks directly to the AC wires of the
alternator. Whenever the alternator is in action (even with the regulator
shut off), the Hobbs (or an other brand of hour meter) gets DC power and is
active too. I got my filter for 65 Euros.
Alfred
Alfred Buess, CH-3052 Zollikofen, Switzerland
E-Mail: ykibuess(at)bluewin.ch
Europa XS #097, Monowheel, Foam wing, Rotax 912ULS, Airmaster 332 CS
-----Ursprngliche Nachricht-----
Von: owner-rotaxengines-list-server(at)matronics.com
[mailto:owner-rotaxengines-list-server(at)matronics.com] Im Auftrag von rampil
Gesendet: Montag, 14. April 2008 12:43
An: rotaxengines-list(at)matronics.com
Betreff: RotaxEngines-List: New HOBBS Idea
--> RotaxEngines-List message posted by: "rampil"
At SnF this year, my best find was a small device for engine time recording.
It is completely independent of and connections to the rest of the aircraft
(power or engine). It time the duration of vibration!
When the engine is running, the timer is going with its own 5 yr battery.
Its made by ENM and I purchased it at PSA aircraft Supply (Lakeland, FL) for
$22 (half retail from ENM)
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176686#176686
________________________________________________________________________________
| From: | "Bret Smith" <smithhb(at)tds.net> |
| Subject: | Re: Another fat wire lug connection |
I just soldered my fat wire connectors using the "Nuckolls Method" and
was surprised how easy it was... Kinda fun actually.
http://www.flightinnovations.com/wiring.html#Installing_Battery_Cable_Con
nectors
Bret Smith
RV-9A "Canopy"
Blue Ridge, GA
www.FlightInnovations.com
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
| Subject: | Re: Another fat wire lug connection |
Robert McCallum wrote:
> Ernest;
>
> While I agree with you totally, you must admit that the results depicted in the
photos appear to be pretty good.
>
Indeed, I must. But how many charred remnants are on the floor? (Or in
his trash can if he isn't as messy as me.)
We're mostly manufacturing one-offs. How many battery cables do you
expect to make in your life? You -could- do the job with a #6 welding
torch set to a large oxidizing flame given enough practice (not that
I've tried it, mind you). Those little butane torches are a godsend in
many applications. This being one of those.
________________________________________________________________________________
| From: | revenson(at)comcast.net (Roger Evenson) |
| Subject: | Voltmeter/Ammeter Recommendations |
Bob: I'd like some clarification on two apparent inconsistencies.
1. On page 4-9, you recommend a battery ammeter, but it appears that in the Z drawings,
you show the ammeter (loadmeter) wired to show alternator output instead.
An inconsistency or am I just ignorant?
2. On page 4-8 (figure 4-5), you show a voltmeter placed on the incoming and ground
sides of the voltage regulator, and provide text on the implications of
various readings. However, Z-23 (note 8) seems to show a voltmeter recommendation
on the alternator field instead (again with good troubleshooting notes).
I'm looking for installation recommendations for one voltmeter and one ammeter
for a Z-11 approach (perhaps w/ 2 Pmags).
Roger, Tucson, AZ
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Another fat wire lug connection |
>Where does one find the solder plugs/
They're a specialty item that's totally
unnecessary to the task. For closed barrel terminals
like that shown in the article, pre-tin your
conductors out in the open. Heat the terminal
and fill the wire-grip about 1/3 full of solder.
Then bring the wire strands up to the rear
of the wire grip . . . warm them along with
the terminal until the solder softens and then
slowly immerse the wire into the terminal.
I prefer the open barrel terminals like those
shown in:
http://aeroelectric.com/articles/big_term.pdf
This style terminal lends itself to "copper-
wedging" so that you can minimize dependency
on solder to fill the joint. You can also
apply solder as needed from the proper end
and avoid overheating the wire's insulation.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| Subject: | Re: Another fat wire lug connection |
| From: | "grjtucson" <george(at)georgejenson.com> |
nuckolls.bob(at)cox.net wrote:
> There's a variety of small gas tools depicted on
> my website at:
>
> http://www.aeroelectric.com/Pictures/Tools/Soldering/Gas_Tools/
>
> Any one of these tools would be very convenient
> sources of heat for putting the terminals on fat-wires.
>
> Bob . . .
I just got one of these:
http://www.aeroelectric.com/Pictures/Tools/Soldering/Gas_Tools/Pencil_Torch_2.jpg
at Ace Hardware for about $12. Kind like a refillable BIC lighter with an attitude.
Worked great to make ground buses, I suspect it'll do a bang-up job on my fat wire
terminals.
George
--------
George Jenson -
Tucson, AZ - RV-7 Standard Build
Empennage Completed 1/06
Wings Completed 11/06
Fuselage in Progress
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=180628#180628
________________________________________________________________________________
| From: | "h&jeuropa" <butcher43(at)att.net> |
I'm having a problem with my comm antenna installed in my Europa. It is a common
copper tape antenna with toroids over the coax. Materials and plans came from
RST Engineering. Installed in the vertical rudder fin per Europa directions
and tuned using a SWR bridge.
When I transmit, certain frequencies cause my ACK ELT to transmit. It is located
on the bottom of the fuselage touching the rear bulkhead (under the elevator
torque tube). This is about 20 inches forward of the antenna and near the tip
of the copper tape. If I disconnect the cable going to the remote actuator,
there is no problem. (I had this problem previously and added toroids to the four
wires but no change).
Also, when I transmit, certain frequencies cause the magnetometer in my GRT EFIS
to swing heading 20 degrees. The magnetometer is mounted on the port side of
the fuselage essentially on the fuselage parting line and just at the rear of
the D panel bulkhead. This is about 60 inches forward of the antenna and about
aligned with the center of the copper tape.
Have others had difficulity with the dipole in the rudder causing problems? Found
a solution? How about using other antennas, like Bob Archer?
Thanks
Jim Butcher
Europa N241BW
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=180803#180803
________________________________________________________________________________
| From: | "Dennis Jones" <djones(at)northboone.net> |
| Subject: | switch for smoke pump |
I would like to wire the panel switch to work as follows:
pump off, pump on and a third position to activate a remote switch to
turn the pump on and off. What would be the proper switch to use and how
would one wire it?
Thanks
Jonsey
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Voltmeter/Ammeter Recommendations |
>
>Bob: I'd like some clarification on two apparent inconsistencies.
>
>1. On page 4-9, you recommend a battery ammeter, but it appears that in
>the Z drawings, you show the ammeter (loadmeter) wired to show alternator
>output instead. An inconsistency or am I just ignorant.
>2. On page 4-8 (figure 4-5), you show a voltmeter placed on the incoming
>and ground sides of the voltage regulator, and provide text on the
>implications of various readings. However, Z-23 (note 8) seems to show a
>voltmeter recommendation on the alternator field instead (again with good
>troubleshooting notes).
>
>I'm looking for installation recommendations for one voltmeter and one
>ammeter for a Z-11 approach (perhaps w/ 2 Pmags).
Understand first that the book speaks to lots of options . . .
not the least of which are a variety of architectures
and choices for instrumentation. The options are so
diverse that one should not take the whole as any
sort of collective recommendation.
Voltmeters and ammeters are not especially useful as
aids to operating an airplane. 99.5% of the time they
say the same thing every time you look at one. In
other words, they only confirm a reading that's easily
predictable. This leaves them with a duty of being a
warning device . . . also not especially useful. Because
they say the same thing most of the time, we tend to
miss them in the scan of important things . . . or
even ignore or dismiss the odd readings when they do
occur.
The PRIMARY electrical system monitor for use in flight
is the active notification of low voltage. When
the light tells you the alternator is not supporting
ship's, there's nothing that a voltmeter or ammeter
adds to knowledge that helps you get down without
breaking a sweat. When the light comes on, you will,
of course, have a plan-B in place that's accomplished
in a timely manner and with minimum pilot workload.
Once on the ground and with tools in hand, voltmeters
and ammeters ARE useful for trouble shooting. Problem
is, that your panel mounted ammeters and voltmeters tend
to sample one place in the system. An objective trouble
shooting activity depends on a host of measurements all
over the system.
Bottom line is, if you'd like to have some panel
decoration that goes beyond the "genius-light", the
options are diverse and no particular combination
of choices is going to make your airplane any easier,
more difficult or more costly to operate.
If it were my airplane, I'd have a low voltage warning
light on the main bus and any aux battery bus. I'd
have a loadmeter on each engine driven power source.
I'd instrument the voltage on the e-bus.
Is that a recommendation? You may view it as such
if you wish. In reality, it's a personal recipe
for success consistent with my design goals and
understanding of the system. You may have different
goals. Know that risks associated with doing something
different (within a boundaries of a well considered
Plan-A/Plan-B modus operandi) are zero.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: switch for smoke pump |
>I would like to wire the panel switch to work as follows:
>pump off, pump on and a third position to activate a remote switch to turn
>the pump on and off. What would be the proper switch to use and how would
>one wire it?
Here's one way . . .
http://www.aeroelectric.com/Pictures/Schematics/Smoke_Oil_Pump_1.pdf
B&C offers a suitable switch. It's their S700-2-10
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net> |
| Subject: | Re: switch for smoke pump |
Jonsey,
I would use a SPDT center off switch (ON - OFF - ON) to select the pump
on,
pump off, remote function. Wire the "pump on" side directly to the
pump.
Wire the "remote" side through a SPST (ON - OFF) switch and back to the
ON
side of the DPDT switch. The SPST switch can be a push button, if you
desire.
When you turn the function switch ON it is "smoke on" until you turn it
off.
When the function switch is REMOTE, it will be "smoke on" only while you
hold the push button.
Roger
________________________________________________________________________________
| From: | "Dennis Jones" <djones(at)northboone.net> |
| Subject: | Re: switch for smoke pump |
Bob
I forgot. I have a light on the panel to let me know the pump is on. Should
I wire that just after the pump on the switch side? Also is that #6 going to
ground? Also if I wanted to wire as Roger had indicated with the off
position in the middle so I could go straight to either the pump on or to
the remote switch would I use the S700-2-1? How would that impact the
wiring?
Thanks
Jonsey
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>
Sent: Saturday, May 03, 2008 8:54 AM
Subject: Re: AeroElectric-List: switch for smoke pump
>
>
>
>>I would like to wire the panel switch to work as follows:
>>pump off, pump on and a third position to activate a remote switch to turn
>>the pump on and off. What would be the proper switch to use and how would
>>one wire it?
>
>
> Here's one way . . .
>
> http://www.aeroelectric.com/Pictures/Schematics/Smoke_Oil_Pump_1.pdf
>
> B&C offers a suitable switch. It's their S700-2-10
>
> Bob . . .
>
>
> ----------------------------------------)
> ( . . . a long habit of not thinking )
> ( a thing wrong, gives it a superficial )
> ( appearance of being right . . . )
> ( )
> ( -Thomas Paine 1776- )
> ----------------------------------------
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Comm Antenna |
>
>I'm having a problem with my comm antenna installed in my Europa. It is a
>common copper tape antenna with toroids over the coax. Materials and plans
>came from RST Engineering. Installed in the vertical rudder fin per Europa
>directions and tuned using a SWR bridge.
>
>When I transmit, certain frequencies cause my ACK ELT to transmit. It is
>located on the bottom of the fuselage touching the rear bulkhead (under
>the elevator torque tube). This is about 20 inches forward of the antenna
>and near the tip of the copper tape. If I disconnect the cable going to
>the remote actuator, there is no problem. (I had this problem previously
>and added toroids to the four wires but no change).
>
>Also, when I transmit, certain frequencies cause the magnetometer in my
>GRT EFIS to swing heading 20 degrees. The magnetometer is mounted on the
>port side of the fuselage essentially on the fuselage parting line and
>just at the rear of the D panel bulkhead. This is about 60 inches forward
>of the antenna and about aligned with the center of the copper tape.
>
>Have others had difficulity with the dipole in the rudder causing
>problems? Found a solution? How about using other antennas, like Bob Archer?
It's probably not the antenna . . . in fact, the BETTER the antenna
works, the worse the problem(s) get.
When crafting products to live in the real worlds aboard
aircraft, the the thoughtful and through designer tries to
anticipate and accommodate every expected stress that might
attack the product's performance.
This process generally includes an assessment of the
design against guidelines cited in DO-160. See:
http://aeroelectric.com/articles/do160.html
Under the topic of Radiated Susceptibility, DO_160
cites a variety of test levels which a product
must stand of without degradation of performance.
Things that are buried in the guts of an all metal
airplane and have no direct sight of external antennas
(either on airplane or off) have the lowest test
levels. Things that have clear sight of and perhaps
close proximity to antennas have the highest test
levels. There is a HUGE difference between the highest
and lowest levels.
In a small plastic airplane, we're faced with the
worst case scenario for friendly system integration.
The exposure probabilities and magnitudes for the
small plastic airplane are as bad or worse than
any of those encountered by the heavy iron birds.
The variables for electro-whizzies responding badly
to comm (or even transponder) signals fall into
three categories.
(1) strength and signature of the interferring
source. Is it radiating stresses that are normally
expected to be under control? In the case of your
transceiver and antenna installation, the strength
is obviously strong . . . and it's unlikely that
were seeing the effects of spurious outputs.
(2) coupling mode. In this case you have close
proximity, un obstructed spaces between an
antenna that's radiating normally and a device
that operates normally . . . except while you're
transmitting.
Can this feature be mitigated? Probably not in
that size airplane constructed of radio energy
transparent materials.
(3) inability of the offended device to operate
in this environment. Unfortunately, may devices
that have served us well in metal airplanes for
decades are seeing new and un-anticipated problems
in plastic airplanes. They may have been
artfully crafted with the metal airplane in mind.
A further consideration is that devices intended
for the OBAM aircraft market are not being produced
by individuals with knowledge of (or perhaps an
interest in) what's needed to work properly
in this relatively unique environment.
I have one such case on my bench right now. The
Van's aircraft ammeter would be hard pressed to
run the gauntlets necessary for qualification
onto type certificated aircraft . . . much less
an OBAM aircraft.
The task before you is daunting without the
support of skills and experience of individuals
who solve these problems for a living. Your
best bet is to get with the manufacturers of
the victim devices and see if any other customers
have experienced difficulty and what remedies
were useful.
Bob . . .
________________________________________________________________________________
| From: | Kevin Horton <khorton01(at)rogers.com> |
| Subject: | Re: Comm Antenna |
On 3-May-08, at 12:24 , Robert L. Nuckolls, III wrote:
> >
>
>> >
>>
>> I'm having a problem with my comm antenna installed in my Europa.
>> It is a common copper tape antenna with toroids over the coax.
>> Materials and plans came from RST Engineering. Installed in the
>> vertical rudder fin per Europa directions and tuned using a SWR
>> bridge.
>>
>> When I transmit, certain frequencies cause my ACK ELT to transmit.
>> It is located on the bottom of the fuselage touching the rear
>> bulkhead (under the elevator torque tube). This is about 20 inches
>> forward of the antenna and near the tip of the copper tape. If I
>> disconnect the cable going to the remote actuator, there is no
>> problem. (I had this problem previously and added toroids to the
>> four wires but no change).
>>
> It's probably not the antenna . . . in fact, the BETTER the antenna
> works, the worse the problem(s) get.
>
It seems that the cable between the ELT and the cockpit control is
acting as an antenna, picking up COM transmissions, and feeding it
into the ELT. This signal coming in on the cable is somehow
interpreted as if the cockpit control had been activated. So, I
wonder if there is a way to shield the cable between the ELT and the
cockpit control, to reduce the amount of energy that it is picking up
from COM transmissions. Also, rerouting that cable further away from
the COM antenna would reduce the energy level it sees.
Bob - the ACK ELT uses a length of apparently conventional telephone
cable to connect the ELT to the cockpit control. Is it worth trying
to replace that telephone cable with some sort of shielded cable,
splicing it into a piece of telephone cable at each end so it has the
correct connectors? If that was tried, where should the shield be
grounded (keeping in mind this is a composite aircraft, and that the
ELT enclosure and cockpit control are both made of plastic)?
--
Kevin Horton RV-8 (final assemby)
Ottawa, Canada
http://www.kilohotel.com/rv8
________________________________________________________________________________
| Subject: | 90 degree disconnect - what kind of crimp tool? |
| From: | "mikef" <mikefapex(at)gmail.com> |
Due to space limitations I have a need for a 90 degree disconnect/fast-on. I've
obtained both the insulated and bare versions but I am not sure how to go about
crimping these little suckers.
I guess I could put them in a vise and screw until crushed flat. Seems heavy handed
after using my nice PIDG crimp tool.
Thanks for any pointers,
Mike
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=180948#180948
________________________________________________________________________________
| Subject: | KY-97 Power Pins |
| From: | "Matt Prather" <mprather(at)spro.net> |
Hey group,
I am helping to install a King Ky-97 comm into a friend's airplane and
have a question about wiring the power pins. The manual lists "SWITCHED
A/C POWER", "13.75 A/C POWER" along with "13.75V POWER". Does anyone know
how these pin groups differ in function? Would it be safe to connect them
all together?
Regards,
Matt-
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: KY-97 Power Pins |
>
>Hey group,
>
>I am helping to install a King Ky-97 comm into a friend's airplane and
>have a question about wiring the power pins. The manual lists "SWITCHED
>A/C POWER", "13.75 A/C POWER" along with "13.75V POWER". Does anyone know
>how these pin groups differ in function? Would it be safe to connect them
>all together?
>
>
>Regards,
>
>Matt-
If I read the data at:
http://www.aeroelectric.com/Installation_Data/KY97A.pdf
correctly, pins 14 and "R" are the ship's power input
from the bus.
Pins 11, 13, "M" and "P" according to Note 4 all get
tied together. If we had a schematic of the radio, I
think we would find that two of the four cited above
are switched power FROM the bus and two others are
power INTO the transponder's electronics. This pair
of pathways are brought out downstream of the transponder
power switch to allow you a switched source of power for
the encoder.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Comm Antenna |
>It seems that the cable between the ELT and the cockpit control is
>acting as an antenna, picking up COM transmissions, and feeding it
>into the ELT. This signal coming in on the cable is somehow
>interpreted as if the cockpit control had been activated. So, I
>wonder if there is a way to shield the cable between the ELT and the
>cockpit control, to reduce the amount of energy that it is picking up
>from COM transmissions. Also, rerouting that cable further away from
>the COM antenna would reduce the energy level it sees.
I've heard this about the ACK ELTs in the past. I
'presume' they've done their homework and meet all
the test requirements levied on them for qualification
in metal airplanes.
>Bob - the ACK ELT uses a length of apparently conventional telephone
>cable to connect the ELT to the cockpit control. Is it worth trying
>to replace that telephone cable with some sort of shielded cable,
>splicing it into a piece of telephone cable at each end so it has the
>correct connectors? If that was tried, where should the shield be
>grounded (keeping in mind this is a composite aircraft, and that the
>ELT enclosure and cockpit control are both made of plastic)?
I presume the problem goes away when the cable is unplugged?
Hmmm . . . shielding a bundle is almost never the best way
to go after an RFI problem. A filter assembly at the ELT's
remote switch connector is the best shot at it. Do you know
which wires in the conductor are common or ground? A few
chokes and capacitors from Digikey could be crafted into
a compact filter that would have high attenuation at
VHF Comm frequencies.
Bob . . .
________________________________________________________________________________
| From: | "Henry Trzeciakowski" <hammer408(at)comcast.net> |
| Subject: | Re: Torque Values |
Bob:
I just can't find any info on what the torque values are for the large
and small terminals on the Battery Contactor and Starter Contactor.
Any assistance appreciated.
Hank
________________________________________________________________________________
| From: | John Morgensen <john(at)morgensen.com> |
| Subject: | Re: Epoxy to Aluminum |
Has anyone tried re-using the click-bond "worms" with standard K1000
plate nuts? It seems to me that the rivet holes would aid in bonding and
the rubber "worm" provides alignment, compression, and protects the
threads from the adhesive.
john
bakerocb(at)cox.net wrote:
>
> 4/28/2008
>
> Hello Dennis, Thanks for your interesting input.
>
> One technique that may be used, if appropriate to the situation, to
> improve joint holding, is to make holes in the aluminum. This permits
> the epoxy to ooze through and form sort of a rivet effect for the glue
> line.
>
> 'OC' Says: "The best investment we can make is the effort to gather
> and understand knowledge."
>
> -----------------------------------------------------------
>
> From: "Dennis Johnson" <pinetownd(at)volcano.net>
> Subject: AeroElectric-List: Epoxy to Aluminum
>
> Greetings,
>
> As part of building a composite airplane, I studied everything I could
> find about epoxies, materials, and adhesive bonding in general. I
> concluded that I did not have the ability to make an epoxy bond to
> aluminum that I could be confident that it wouldn't fail.
>
> The problem is that aluminum begins oxidizing immediately after
> cleaning. No matter how quick you are, unless you use extraordinary
> measures, there will be aluminum oxide on the surface you are bonding.
> Aluminum oxide has relatively low strength. The epoxy bonds well to the
> aluminum oxide, but the aluminum oxide isn't stuck very well to the
> underlying aluminum. After some number of hot/cold and wet/dry cycles,
> the bond may weaken enough to fail.
>
> Obviously, Boeing and others solved this problem long ago. However,
> based on the great reference book, "Composite Basics," by Andrew
> Marshall, their methods aren't practical for most of us homebuilders.
>> From chapter 11, Marshall says, "Unfortunately, both the FPL etch and
> the PAA treatments (the ones widely and successfully used in the
> industry) involve extensive chemical control and a large investment in
> equipment."
>
> As an interesting aside, he describes an industry standard "wedge" test
> where two .125" thick aluminum pieces are bonded together. After
> curing, a wedge is driven into the end of the assembly, between the two
> pieces of aluminum, which forces the bond to break at that point. A
> mark is placed at the point where the fracture stops. The test piece is
> then placed into a warm, wet chamber for one hour. The assembly is then
> removed and the additional distance the crack propagated during the
> warm/wet test is measured. If the crack grew less than three-fourths of
> an inch, the bond is considered to be good for life. Marshall says that
> if the aluminum was cleaned but not chemically treated, the assembly
> will likely totally delaminate during the one hour test!
>
> Since I didn't have the ability to duplicate Boeing's chemical treatment
> process, I didn't make any bond to aluminum that would cause anything
> more than inconvenience if it failed. Heat and humidity seem to be the
> culprits, which might explain why some people report long lasting bonds
> and others have failures.
>
> Best,
> Dennis
>
>
________________________________________________________________________________
| From: | "Dennis Jones" <djones(at)northboone.net> |
| Subject: | AC switches in DC applications |
Bob
I know this has been discussed before. I'm unable to find the reference
in the connection about AC switches, there ratings and how to make sure
you are using an appropriate AC switch in a DC application.
Thanks
Jonsey
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: AC switches in DC applications |
You may find at least some of the answers you need in Bob's article here:
http://www.bandc.biz/swtchrat.pdf
Ron
On Sun, May 4, 2008 at 10:00 AM, Dennis Jones wrote:
> Bob
>
> I know this has been discussed before. I'm unable to find the reference in
> the connection about AC switches, there ratings and how to make sure you are
> using an appropriate AC switch in a DC application.
>
> Thanks
> Jonsey
>
________________________________________________________________________________
| From: | Larry Rosen <LarryRosen(at)comcast.net> |
| Subject: | ANL Current Limiter to protect 10 AWG Wire |
I need some guidance.
I want to use 10 AWG wire from my SD-20 alternator to feed my endurance
bus.
I would like to use an ANL current limiter to protect the wire.
B&C sells a 40 amp ANL and Bussman makes a 35 amp ANL (does anyone have
a source for this 35 amp ANL)
The wire table (Fig 8-3) in the connection suggests 30 amp protection
for 10 AWG wire.
Is 35 or 40 amp protection on this wire acceptable?
Would I be better off using a 14 AWG fusible link?
In addition in this circuit I want to use a S704-1 relay that is rated
at 20 amps, do I need to protect the relay? The maximum loads off the
relay are well below the 20 amps, but if it does see excessive currents,
how does it fail?
Larry Rosen
________________________________________________________________________________
| Subject: | Re: KY-97 Power Pins |
| From: | "Matt Prather" <mprather(at)spro.net> |
Thanks for the input Bob. They KY-97 is a comm radio however.
I wired the unit according to the manual (a copy of which Bill posted),
and it seems to power up okay - no antenna hooked up so haven't tried
transmitting/receiving yet. I had speculated that the loop put an
internal regulator in the correct mode, but still not sure.
Regards,
Matt-
>
>
>
>>
>>
>>Hey group,
>>
>>I am helping to install a King Ky-97 comm into a friend's airplane and
>>have a question about wiring the power pins. The manual lists "SWITCHED
>>A/C POWER", "13.75 A/C POWER" along with "13.75V POWER". Does anyone
>> know
>>how these pin groups differ in function? Would it be safe to connect
>> them
>>all together?
>>
>>
>>Regards,
>>
>>Matt-
>
> If I read the data at:
>
> http://www.aeroelectric.com/Installation_Data/KY97A.pdf
>
> correctly, pins 14 and "R" are the ship's power input
> from the bus.
>
> Pins 11, 13, "M" and "P" according to Note 4 all get
> tied together. If we had a schematic of the radio, I
> think we would find that two of the four cited above
> are switched power FROM the bus and two others are
> power INTO the transponder's electronics. This pair
> of pathways are brought out downstream of the transponder
> power switch to allow you a switched source of power for
> the encoder.
>
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: ANL Current Limiter to protect 10 AWG Wire |
Larry,
FWIW, I was convinced by a number of folks that #12 AWG was adequate for
both my Jabiru 3300's nominal 20A alternator AND for the SD-20S backup,
which have separate charging output circuits, of course. If you look at
AC43, you'll see that in short lengths, #12 is plenty big enough for even
30A. I don't expect to ever draw more than 25A from either alternator, and
then only for rare, short periods, after a long cold start followed by
fairly immediate high RPM, i.e., poor battery mgmt.
On advice of B&C, for over current protection I went with an 30A ATC inline
blade fuse, one for each alternator, and the S704-1 relay to provide
switching for one leg of the Jabiru PM alternator's output (no field circuit
there) for OV protection. I don't think you need a relay for the SD-20,
because the OVP scheme (whether inboard with the LR3C regulator, or one of
the outboard "crowbar" circuits) will shut down the alternator by cutting
the field circuit, wired in series with your panel ALT switch.
Ron
On Sun, May 4, 2008 at 2:50 PM, Larry Rosen wrote:
> LarryRosen(at)comcast.net>
>
> I need some guidance.
>
> I want to use 10 AWG wire from my SD-20 alternator to feed my endurance
> bus.
> I would like to use an ANL current limiter to protect the wire.
> B&C sells a 40 amp ANL and Bussman makes a 35 amp ANL (does anyone have a
> source for this 35 amp ANL)
> The wire table (Fig 8-3) in the connection suggests 30 amp protection for
> 10 AWG wire.
> Is 35 or 40 amp protection on this wire acceptable?
> Would I be better off using a 14 AWG fusible link?
> In addition in this circuit I want to use a S704-1 relay that is rated at
> 20 amps, do I need to protect the relay? The maximum loads off the relay
> are well below the 20 amps, but if it does see excessive currents, how does
> it fail?
>
> Larry Rosen
>
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: ANL Current Limiter to protect 10 AWG Wire |
Forgot to mention that Potter & Brumfield, makers of the S704-1, rate it for
30A through the N.O. contact when used in SPST configuration. If I'm paying
attention, it should hardly ever see more than 20A, and never more than 30A
from the Jabiru's PM alternator.
Ron
________________________________________________________________________________
| From: | Frank Davis <ffdavis(at)earthlink.net> |
| Subject: | Re: Epoxy to Aluminum |
Yes, I have re-used the "worms" with K1000 nutplates and J-B Weld.
Worked well. However if the plate is in a critical non-accesable
location, I spring for the more expensive Click-Bond adhesive (paranoia).
As an aside, Click-Bond is located at the Carson City Airport, NV,
where my EAA Chapter is. We have toured the factory several time. One
of the things discussed was the strength of the adhesive bond. They
said that while it doesn't have great peel strength, it has good shear
strength, which is required to counteract the torque of inserting the
fastener.
Frank
*From: * */John Morgensen <john(at)morgensen.com
>/*
*Subject: * /*_Re: Epoxy to Aluminum_*/
* Has anyone tried re-using the click-bond "worms" with standard K1000
plate nuts? It seems to me that the rivet holes would aid in bonding and
the rubber "worm" provides alignment, compression, and protects the
threads from the adhesive. john*
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: Z-19 Item Clarification |
On Mon, May 5, 2008 at 6:06 AM, wrote:
> -...
> 1. The DC Power Master Off/Bat/Bat + Alt switch depicted on the diagram
> does print clearly in terms of the switch number. Is that a (2-10) or
> (2-11)?
It's S700-2-10
> 2. I have the 48 point B & C grounding block on instrument panel (G3) do
> I need to bother with the avionics ground bus? All of my equipment is
> close by and I have 48 connections there anyway, why not use G3?
No need for a separate avionics ground bus.
> 3. What is the B & C part number for the alternate e-bus feed relay?
>
The B&C S704-1 will work well. Small, light, and low current drain.
(Depending on your architecture, if the E-bus load isn't too large, you may
not need a relay.)
Ron
________________________________________________________________________________
| From: | "Terry Frazier" <fraziernv(at)earthlink.net> |
FWIW, I looked up the installation instructions on the artex ME406 ELT
http://www.artex.net/products/oneproduct.php?categoryid=15&productid=87 .
They call for a shielded cable between the ELT and the control panel. I
decided to go with the C91a ELT, but ran the shielded cable from the ELT
location to the panel for future upgrade ease. I'm no expert, but I'd try
the shielded control cable first.
Terry
7A Panel
SNIP
From: "Dennis Jones" <djones(at)northboone.net>
Subject: Re: AeroElectric-List: switch for smoke pump
From: Kevin Horton <khorton01(at)rogers.com>
Subject: Re: AeroElectric-List: Comm Antenna
On 3-May-08, at 12:24 , Robert L. Nuckolls, III wrote:
> >
>
>> >
>>
>> I'm having a problem with my comm antenna installed in my Europa.
>> It is a common copper tape antenna with toroids over the coax.
>> Materials and plans came from RST Engineering. Installed in the
>> vertical rudder fin per Europa directions and tuned using a SWR
>> bridge.
>>
>
It seems that the cable between the ELT and the cockpit control is
acting as an antenna, picking up COM transmissions, and feeding it
into the ELT. This signal coming in on the cable is somehow
interpreted as if the cockpit control had been activated. So, I
wonder if there is a way to shield the cable between the ELT and the
cockpit control, to reduce the amount of energy that it is picking up
from COM transmissions. Also, rerouting that cable further away from
the COM antenna would reduce the energy level it sees.
Bob - the ACK ELT uses a length of apparently conventional telephone
cable to connect the ELT to the cockpit control. Is it worth trying
to replace that telephone cable with some sort of shielded cable,
splicing it into a piece of telephone cable at each end so it has the
correct connectors? If that was tried, where should the shield be
grounded (keeping in mind this is a composite aircraft, and that the
ELT enclosure and cockpit control are both made of plastic)?
--
Kevin Horton RV-8 (final assemby)
Ottawa, Canada
http://www.kilohotel.com/rv8
SNIP
________________________________________________________________________________
| Subject: | Z-19 Item Clarification |
Excellent,
Thanks Ron
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ron
Shannon
Sent: Monday, May 05, 2008 12:03 PM
To: aeroelectric-list(at)matronics.com
Subject: Re: AeroElectric-List: Z-19 Item Clarification
On Mon, May 5, 2008 at 6:06 AM, wrote:
-...
1. The DC Power Master Off/Bat/Bat + Alt switch depicted
on the diagram
does print clearly in terms of the switch number. Is
that a (2-10) or
(2-11)?
It's S700-2-10
2. I have the 48 point B & C grounding block on
instrument panel (G3) do
I need to bother with the avionics ground bus? All of my
equipment is
close by and I have 48 connections there anyway, why not
use G3?
No need for a separate avionics ground bus.
3. What is the B & C part number for the alternate e-bus
feed relay?
The B&C S704-1 will work well. Small, light, and low current
drain. (Depending on your architecture, if the E-bus load isn't too
large, you may not need a relay.)
Ron
________________________________________________________________________________
| From: | "Bill Bradburry" <bbradburry(at)bellsouth.net> |
The instructions call for a 1/4 amp slo blo fuse. Any ideas as to where to
source this item?
Bill B
________________________________________________________________________________
| Subject: | Re: Comm Antenna |
| From: | "rampil" <ira.rampil(at)gmail.com> |
Hi Jim,
I agree that the ELT remote head cable is picking up the com signal.
Most Europas I have dived into (including mine) use standard
unshielded telephone quad cable. My King 450 ELT does not pick up
the RFI as a test button press however.
The right sized toroids at the ELT end of the cable might help,
Changing the length of the cable (to move it from a resonance, might help,
finally, shield the cable.
Unless of course you think its time to get a new UHF ELT ;-)
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=181271#181271
________________________________________________________________________________
| Subject: | Re: Comm Antenna |
| From: | "Alfio" <longeron(at)gmail.com> |
Terry,
This may not be your problem or situation, however .....
One thing I noticed about the ACK installation, is that their antenna cannot be
substituted for another one. It is part and parcel of the EMC filtering of the
unit. According to ACK, other RF signals (e.g. comm) can be received via the
ACK antenna port and falsely trigger the unit.
If you did not substitute the antenna, then this would not apply.
Alfio
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=181273#181273
________________________________________________________________________________
| Subject: | Re: Comm Antenna |
| From: | "Matt Prather" <mprather(at)spro.net> |
snip
> Unless of course you think its time to get a new UHF ELT ;-)
A UHF ELT might not have remote circuitry that is any more immune to VHF
RF energy than one of the VHF ULTs...
Regards,
Matt-
________________________________________________________________________________
| From: | <gmcjetpilot(at)yahoo.com> |
| Subject: | Re: Comm Antenna (ACK ELT RFI issue) |
Change the length and / or the routing of the ACK ELT phone line, from panel switch
to unit.
Yes a shielded wire cable would probably do it. Personally I didn't like the
telephone wire in my plane and fab'ed a 22awg cable, twisting the wires together.
Before that I few with the standard phone line and did not have an RFI issue.
I made the change to make it more durable. For what it's worth, my new Artex
ELT uses discrete wires to connect the panel control/indicator to ELT unit.
G
---------------------------------
Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | oil pressure warn logic |
Here's a puzzle. It may be a "can't get there from here" or a "why bother"
situation, but I know some of you listers love a challenge. :-)
I have a B&C S8012 oil pressure switch, where the N.C. contact is wired to
an oil pressure warning LED. (See http://www.bandc.biz/S8012dwg.pdf) I also
have an ACS OFF-L-R-BOTH key switch for the mags (separate START button) and
an S700-2-10 master switch. The issue is that I would like the oil pressure
warning LED to operate only when the ACS key switch is not OFF, e.g., when
it's in any of the L-R-BOTH positions. The reason is that I don't want the
oil pressure warning light ON when I'm just running the panel during engine
off ground ops. I plan a separate master ON nag LED, also wired through the
N.C. contact.
In short, I'd like to distinguish between A) master only ON, and B) master
AND key switch ON.
It's apparent that I need to incorporate the logic of the key switch (see
Z-27 logic table) into the low oil pressure warning LED circuit somehow but
I'm bamboozled as to how to do it, especially in a way that won't defeat the
purpose of the mag switch(s). Of course, I'd rather not add another relay,
but additional diode switching logic might be OK.
Ron
________________________________________________________________________________
| Subject: | Re: oil pressure warn logic |
| From: | "Matt Prather" <mprather(at)spro.net> |
If course, you could get rid of the key switch in favor of a couple of
simple toggle switches. One of the toggle switches could have an extra
pole which would defeat the OP light when off. Easy.
I don't think the ACS key switch has any unused poles. I don't see a way
to control the OP light with the key switch without adding some fail modes
to the magneto operation. And needless complexity.
As was mentioned by a lister a while back concerning controlling the Hobbs
by means of monitoring alternator operation, a similar method could be
used to control the OP warning light.
With a couple of components, you could add a "defeat" circuit which would
allow suppressing the OP light operation by means of a momentary push
button. Turn the master on, press the OP warning "defeat" button, and the
light goes out. Next time the master is cycled, the OP warning functions
as expected.
Finally, why are you concerned about the OP warning being on when with
engine-off operations? It probably won't burn as much power as anything
else in the panel.. I guess that fits into the "why bother" response
category... :)
Regards,
Matt-
> Here's a puzzle. It may be a "can't get there from here" or a "why bother"
> situation, but I know some of you listers love a challenge. :-)
>
> I have a B&C S8012 oil pressure switch, where the N.C. contact is wired to
> an oil pressure warning LED. (See http://www.bandc.biz/S8012dwg.pdf) I
> also
> have an ACS OFF-L-R-BOTH key switch for the mags (separate START button)
> and
> an S700-2-10 master switch. The issue is that I would like the oil
> pressure
> warning LED to operate only when the ACS key switch is not OFF, e.g., when
> it's in any of the L-R-BOTH positions. The reason is that I don't want
> the
> oil pressure warning light ON when I'm just running the panel during
> engine
> off ground ops. I plan a separate master ON nag LED, also wired through
> the
> N.C. contact.
>
> In short, I'd like to distinguish between A) master only ON, and B) master
> AND key switch ON.
>
> It's apparent that I need to incorporate the logic of the key switch (see
> Z-27 logic table) into the low oil pressure warning LED circuit somehow
> but
> I'm bamboozled as to how to do it, especially in a way that won't defeat
> the
> purpose of the mag switch(s). Of course, I'd rather not add another relay,
> but additional diode switching logic might be OK.
>
> Ron
>
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: oil pressure warn logic |
Thanks, Matt. All points well taken.
One reason to have that light OFF during engine off ground ops would be to
make it more palatable to use a blinking LED. After due deliberations, I
committed to the key switch some time back. As you point out, it would have
been easy with mag toggles. A latching defeat switch, perhaps with an auto
timeout in addition to the master cycle reset you suggest, is a possibility.
Of course, the oil pressure warn is critical, and mandates a KISS
architecture. No doubt, it's my inclination to complicate it that deserves a
defeat switch. :-)
Ron
On Mon, May 5, 2008 at 1:29 PM, Matt Prather wrote:
> >
>
> If course, you could get rid of the key switch in favor of a couple of
> simple toggle switches. One of the toggle switches could have an extra
> pole which would defeat the OP light when off. Easy.
>
> I don't think the ACS key switch has any unused poles. I don't see a way
> to control the OP light with the key switch without adding some fail modes
> to the magneto operation. And needless complexity.
>
> As was mentioned by a lister a while back concerning controlling the Hobbs
> by means of monitoring alternator operation, a similar method could be
> used to control the OP warning light.
>
> With a couple of components, you could add a "defeat" circuit which would
> allow suppressing the OP light operation by means of a momentary push
> button. Turn the master on, press the OP warning "defeat" button, and the
> light goes out. Next time the master is cycled, the OP warning functions
> as expected.
>
> Finally, why are you concerned about the OP warning being on when with
> engine-off operations? It probably won't burn as much power as anything
> else in the panel.. I guess that fits into the "why bother" response
> category... :)
>
>
> Regards,
>
> Matt-
>
________________________________________________________________________________
| From: | Fiveonepw(at)aol.com |
| Subject: | Re: Comm Antenna (ACK ELT RFI issue) |
In a message dated 05/05/2008 2:00:10 PM Central Daylight Time,
gmcjetpilot(at)yahoo.com writes:
Change the length and / or the routing of the ACK ELT phone line, from panel
switch to unit.
>>>
On a tangent, the ACKs I've installed in RVs have remote cables MUCH longer
than needed. I simply coiled the extra up and ty-wrapped near the ELT without
difficulty. If done likewise in a composite a/c and the coil were in close
proximity to the antagonist, might this cause the activation by acting like a
transformer secondary amplifying com signal leakage? Is there any excess cable
bundled near the com coax or antenna?
Mark
**************Wondering what's for Dinner Tonight? Get new twists on family
favorites at AOL Food.
(http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001)
________________________________________________________________________________
| From: | MR Corder <mike.corder(at)sbcglobal.net> |
I have an SD-8 back up alternator on my RV-7A. I'm just curious if most
people leave it running on all the time (i.e. do the two alternators
fight each other ?) or just plan on turning it on if the main unit fails.
Mike Corder
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: SD-8 on when ? |
>
>I have an SD-8 back up alternator on my RV-7A. I'm just curious if most
>people leave it running on all the time (i.e. do the two alternators fight
>each other ?) or just plan on turning it on if the main unit fails.
>
>Mike Corder
The original design philosophy behind Z-13/8 was to use the SD-8
as a back-up alternator in a two-layer electrical system. There
is no need nor advantage in running the SD-8 in tandem with the
main alternator (unless you main alternator is undersized . . .
in which case you have a design issue much more serious than
deciding how to run the SD-8).
They don't "fight" each other but there's no operational
rationale for tandem operation.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: oil pressure warn logic |
>Thanks, Matt. All points well taken.
>
>One reason to have that light OFF during engine off ground ops would be to
>make it more palatable to use a blinking LED. After due deliberations, I
>committed to the key switch some time back. As you point out, it would
>have been easy with mag toggles. A latching defeat switch, perhaps with an
>auto timeout in addition to the master cycle reset you suggest, is a
>possibility.
>
>Of course, the oil pressure warn is critical, and mandates a KISS
>architecture. No doubt, it's my inclination to complicate it that deserves
>a defeat switch. :-)
>
>Ron
Do you have a low voltage warning light? Does it not flash?
The reason for flashing lights is to get attention to an
urgent matter. Another advantage of flashing lights is to
remind you to turn the master switch(es) off after engine
shutdown.
I'm curious as to the driver behind efforts to defeat the
ideas that drove the original design goals for these lights.
Bob . . .
________________________________________________________________________________
| From: | CardinalNSB(at)aol.com |
| Subject: | Info on TKM "LED" cdi |
Can anyone direct me to info on the TKM cdi, in particular whether it will
work with the Garmin and King KNS80 units (I know they need a resolver)? and
whether its internal switcher switches all input, or if it is like the King
209A and apparently bypasses the resolver?
Anyone use this unit, like or not, I know some don't like the led lights and
prefer the needles?
Thanks, Skip
**************Wondering what's for Dinner Tonight? Get new twists on family
favorites at AOL Food.
(http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001)
________________________________________________________________________________
| From: | "Joe" <fran5sew(at)banyanol.com> |
| Subject: | Re: oil pressure warn logic |
Ron,
You could check the continuity of the unused terminals LR and BO on the
back of the ACS key switch. Check from LR and BO to BAT and to GROUIND
and to terminals R and L with the switch in different positions. Report
your findings back here and maybe someone can use that information to
help you. Even if those unused terminals are of no use for your
application, knowing how they are wired is useful information that could
help others. This website
http://www.aircraftspruce.com/pdf/2008Individual/Cat08448.pdf has a
pinout of the back of the switch, but there is no schematic to show
exactly how the switch is wired internally. Adding a circuit component
that disables the low pressure warning light introduces a failure point
that could prevent the light from warning you when needed.
Joe
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: oil pressure warn logic |
>Ron,
>You could check the continuity of the unused terminals LR and BO on the
>back of the ACS key switch. Check from LR and BO to BAT and to GROUIND
>and to terminals R and L with the switch in different positions. Report
>your findings back here and maybe someone can use that information to help
>you. Even if those unused terminals are of no use for your application,
>knowing how they are wired is useful information that could help
>others. This website
><http://www.aircraftspruce.com/pdf/2008Individual/Cat08448.pdf>http://www.aircraftspruce.com/pdf/2008Individual/Cat08448.pdf
>has a pinout of the back of the switch, but there is no schematic to show
>exactly how the switch is wired internally. Adding a circuit component
>that disables the low pressure warning light introduces a failure point
>that could prevent the light from warning you when needed.
>Joe
Functionality of the internal workings of the classic off-l-r-both-start
switch is described at:
http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z26-27K.pdf
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: oil pressure warn logic |
On Tue, May 6, 2008 at 6:24 AM, Robert L. Nuckolls, III <
nuckolls.bob(at)cox.net> wrote:
> nuckolls.bob(at)cox.net>
>
>
> Thanks, Matt. All points well taken.
> >
> > One reason to have that light OFF during engine off ground ops would be
> > to make it more palatable to use a blinking LED. After due deliberations, I
> > committed to the key switch some time back. As you point out, it would have
> > been easy with mag toggles. A latching defeat switch, perhaps with an auto
> > timeout in addition to the master cycle reset you suggest, is a possibility.
> >
> > Of course, the oil pressure warn is critical, and mandates a KISS
> > architecture. No doubt, it's my inclination to complicate it that deserves
a
> > defeat switch. :-)
> >
> > Ron
> >
>
> Do you have a low voltage warning light? Does it not flash?
> The reason for flashing lights is to get attention to an
> urgent matter. Another advantage of flashing lights is to
> remind you to turn the master switch(es) off after engine
> shutdown.
>
> I'm curious as to the driver behind efforts to defeat the
> ideas that drove the original design goals for these lights.
>
> Bob . . .
Bob, I thought I had explained the driver -- not necessarily a sufficient
one -- to allow ground ops (programming GPS, etc.) without having the oil
pressure warn light blinking away. (Yes, my LV warn light will blink, and
the same issue may apply when not on ground power.)
I did concede at the outset and again above that this concern may not be
important enough to change the circuit, logic, etc. Just a puzzle that I
thought worthy of discussion if, and only if, it could be solved safely and
reliably.
Ron
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
>
>
> The instructions call for a 1/4 amp slo blo fuse. Any ideas as to where to
>source this item?
http://www.elexp.com/fus_0mdl.htm
Bob . . .
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: oil pressure warn logic |
On Tue, May 6, 2008 at 7:55 AM, Joe wrote:
> Ron,
> You could check the continuity of the unused terminals LR and BO on the
> back of the ACS key switch. Check from LR and BO to BAT and to GROUIND and
> to terminals R and L with the switch in different positions. Report your
> findings back here and maybe someone can use that information to help you.
> Even if those unused terminals are of no use for your application, knowing
> how they are wired is useful information that could help others. This
> website http://www.aircraftspruce.com/pdf/2008Individual/Cat08448.pdf has
> a pinout of the back of the switch, but there is no schematic to show
> exactly how the switch is wired internally. Adding a circuit component that
> disables the low pressure warning light introduces a failure point that
> could prevent the light from warning you when needed.
> Joe
>
The key switch model without START doesn't have those terminals. Just GND, L
and R.
I realize this proposal could introduce failure points, and thought I had
already acknowledged that, though perhaps not enough. Surely the fact that
some proposal may introduce failure points if not done right is not a reason
to explore possible ways to do it right.
Ron
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: oil pressure warn logic |
On Tue, May 6, 2008 at 10:26 AM, Robert L. Nuckolls, III <
nuckolls.bob(at)cox.net> wrote:
> nuckolls.bob(at)cox.net>
> ...
> Functionality of the internal workings of the classic off-l-r-both-start
> switch is described at:
>
> http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z26-27K.pdf
>
>
> Bob . . .
>
Understood. I referenced Z-27 in the first post in this thread.
Ron
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: AC switches in DC applications |
>Bob
>
>I know this has been discussed before. I'm unable to find the reference in
>the connection about AC switches, there ratings and how to make sure you
>are using an appropriate AC switch in a DC application.
>
>Thanks
>Jonsey
See http://aeroelectric.com/articles/Switch_Ratings.pdf
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: AW: New HOBBS Idea |
>
>
> There is another clever solution for hooking up the Hobbs to your engine:
>Comco Ikarus (http://www.comco-ikarus.de/index_english.html) sells an
>electronic filter produced by Utz Schicke (producer of the Schicke GR6
>regulator for Rotax engines) which hooks directly to the AC wires of the
>alternator. Whenever the alternator is in action (even with the regulator
>shut off), the Hobbs (or an other brand of hour meter) gets DC power and is
>active too. I got my filter for 65 Euros.
It's also possible to do-it-yerself. Here's an approach
I sketched for some folks several years ago:
http://www.aeroelectric.com/Pictures/Schematics/Hourmeter_Adapter_for_PM_Alternators.pdf
It's a simple AC/DC rectifier combined with a shunt regulator
to keep the capacitor from charging up to un-restrained maximum
that can be well over 50 volts in cruise rpm.
The transistor needs to be heat-sinked to an aluminum
enclosure. It should also be insulated from the heatsink.
Hence the call-out for an insulator kit on the drawing.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: 90 degree disconnect - what kind of crimp tool? |
>
>Due to space limitations I have a need for a 90 degree disconnect/fast-on.
>I've obtained both the insulated and bare versions but I am not sure how
>to go about crimping these little suckers.
>
>I guess I could put them in a vise and screw until crushed flat. Seems
>heavy handed after using my nice PIDG crimp tool.
>
>Thanks for any pointers,
>
>Mike
If your existing tools won't do it, you can look for
an alternative tool or process. Consider the hardware
store tool like:
http://www.aeroelectric.com/Pictures/Tools/Crimp_Tools/Two_Shot_Crimp_Tool.jpg
Tools specific to that terminal are probably not cheap
and you only need to do a few installations.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| Subject: | AW: New HOBBS Idea |
Ira,
Great find. This has to be the simplest solution yet. No wires! Yeah! I suppose
it still have moving parts like those old Swiss watch movements where you shook
them up to wind them, but it should last for years. The best price I found
so far is about $50.00 from ENM. If anyone finds a better price, please post.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Europa (Alfred Buess)
Sent: Thursday, May 01, 2008 3:37 AM
Subject: AeroElectric-List: AW: New HOBBS Idea
-->
There is another clever solution for hooking up the Hobbs to your engine: Comco Ikarus (http://www.comco-ikarus.de/index_english.html) sells an electronic filter produced by Utz Schicke (producer of the Schicke GR6 regulator for Rotax engines) which hooks directly to the AC wires of the alternator. Whenever the alternator is in action (even with the regulator shut off), the Hobbs (or an other brand of hour meter) gets DC power and is active too. I got my filter for 65 Euros.
Alfred
Alfred Buess, CH-3052 Zollikofen, Switzerland
E-Mail: ykibuess(at)bluewin.ch
Europa XS #097, Monowheel, Foam wing, Rotax 912ULS, Airmaster 332 CS
-----Ursprngliche Nachricht-----
Von: owner-rotaxengines-list-server(at)matronics.com
[mailto:owner-rotaxengines-list-server(at)matronics.com] Im Auftrag von rampil
Gesendet: Montag, 14. April 2008 12:43
An: rotaxengines-list(at)matronics.com
Betreff: RotaxEngines-List: New HOBBS Idea
--> RotaxEngines-List message posted by: "rampil"
At SnF this year, my best find was a small device for engine time recording. It
is completely independent of and connections to the rest of the aircraft (power
or engine). It time the duration of vibration!
When the engine is running, the timer is going with its own 5 yr battery. Its made
by ENM and I purchased it at PSA aircraft Supply (Lakeland, FL) for $22 (half
retail from ENM)
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=176686#176686
________________________________________________________________________________
| From: | "Henry Trzeciakowski" <hammer408(at)comcast.net> |
| Subject: | Fw: Torque Values |
----- Original Message -----
From: Henry Trzeciakowski
Sent: Sunday, May 04, 2008 10:15 AM
Subject: Re: Torque Values
Bob:
I just can't find any info on what the torque values are for the large
and small terminals on the Battery Contactor and Starter Contactor.
Any assistance appreciated.
Hank
________________________________________________________________________________
| From: | "Bill Bradburry" <bbradburry(at)bellsouth.net> |
Thanks, Bob.
I will have to look around in there a little. They have a $20 min order and
my fuse and holder is only about $1.35.
Bill B
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Tuesday, May 06, 2008 1:31 PM
Subject: Re: AeroElectric-List: Artex ME406
-->
>
>
> The instructions call for a 1/4 amp slo blo fuse. Any ideas as to
>where to source this item?
http://www.elexp.com/fus_0mdl.htm
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
>
>
>Thanks, Bob.
>I will have to look around in there a little. They have a $20 min order and
>my fuse and holder is only about $1.35.
>
>Bill B
Okay. Consider the fuse offerings at Radio Shack. That "1/4A
Slo-Blo" citation is somewhat arcane. It has the look and
smell of some attempt to protect internals of a product
for the consequences of failure of internal components.
It's poor etiquette to push such a task off on the
installer/owner of a product.
I cannot imagine the physics that makes a 1/4A-SB fuse
so attractive. I'd be willing to bet that a perfectly
ordinary 1A device would do just as well and be MUCH
easier to find.
If it were my installation, I'd go with a 1A standard
fast blow and see if I get any nuisance tripping. Radio
Shack can fix you up with fuses at attractive over-the-
counter prices.
Bob . . .
________________________________________________________________________________
| From: | "Bill Denton" <bdenton(at)bdenton.com> |
JFTR: The only thing powered through this fuse is an LED.
Thanks!
Bill Denton
bdenton(at)bdenton.com
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Wednesday, May 07, 2008 8:38 AM
Subject: RE: AeroElectric-List: Artex ME406
>
>
>Thanks, Bob.
>I will have to look around in there a little. They have a $20 min order
and
>my fuse and holder is only about $1.35.
>
>Bill B
Okay. Consider the fuse offerings at Radio Shack. That "1/4A
Slo-Blo" citation is somewhat arcane. It has the look and
smell of some attempt to protect internals of a product
for the consequences of failure of internal components.
It's poor etiquette to push such a task off on the
installer/owner of a product.
I cannot imagine the physics that makes a 1/4A-SB fuse
so attractive. I'd be willing to bet that a perfectly
ordinary 1A device would do just as well and be MUCH
easier to find.
If it were my installation, I'd go with a 1A standard
fast blow and see if I get any nuisance tripping. Radio
Shack can fix you up with fuses at attractive over-the-
counter prices.
Bob . . .
________________________________________________________________________________
| From: | CardinalNSB(at)aol.com |
| Subject: | Cessna erector set flap switch, why? |
My Cessna flap switch looks like my 4th grade erector set science project,
open contacts, bakelite or something, huge, scary, lots of cross wires.
Not considering the FAA issues, would a 20 amp Eaton mom off mom be a good
choice as far as electrical/physical qualities? I see other Cessnas used the
mom switches. Is my 177 flap motor (probablly the same as 172?) something
special in its design that the "open erector set architecture" is necessary?
Thank you all, Skip
**************Wondering what's for Dinner Tonight? Get new twists on family
favorites at AOL Food.
(http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001)
________________________________________________________________________________
| From: | "earl_schroeder(at)juno.com" <earl_schroeder(at)juno.com> |
-- "Robert L. Nuckolls, III" wrote:
I cannot imagine the physics that makes a 1/4A-SB fuse
so attractive. I'd be willing to bet that a perfectly
ordinary 1A device would do just as well and be MUCH
easier to find.
Hi Bob,
When working for GE Plastics, we used 1/4A SB fuses in all the 24VDC process control
loops [4-20ma]. Perhaps the primary reason was to negate the trip up or
down multiple floors to the control room to replace a fuse we inadvertently blew
when the screwdriver slipped a bit.
The original design was for regular fuses but they were quickly replaced to save
steps and time... the loop wiring was 18ga twisted Beldon always run in metal
conduit. In the 30+ years of employment, I never saw a fault in the wiring
that actually required a fuse. A few defective amplifiers did pop the fuse however
[used in flow, level, pressure & temp control].
Earl
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Cessna erector set flap switch, why? |
>My Cessna flap switch looks like my 4th grade erector set science project,
>open contacts, bakelite or something, huge, scary, lots of cross wires.
>
>Not considering the FAA issues, would a 20 amp Eaton mom off mom be a good
>choice as far as electrical/physical qualities? I see other Cessnas used
>the mom switches. Is my 177 flap motor (probablly the same as 172?)
>something special in its design that the "open erector set architecture"
>is necessary?
>
>Thank you all, Skip
Yeah, I vaguely remember that thing. I think at the time
the flap control system of choice used a pair of microswitches
mounted on the flap handle . . . the switches were actuated
by a cam attached to the flap extension mechanism by a
Bowden control cable. A pretty simple, on/off servo system
that was easy to build and maintain.
I don't recall now how the switch was used on the 177.
Do you have a flap system schematic from the maintenance
manual that you could share with us?
Bob . . .
________________________________________________________________________________
| From: | "Joe" <fran5sew(at)banyanol.com> |
| Subject: | Re: oil pressure warn logic |
Ron,
Looking at the schematic that Bob K provided on Z-26, there are no
unused contacts on the key switch. Connecting to the left or right mag
wires is a bad idea because doing so might disable the magneto. Here is
a suggestion: Tape a piece of reflective tape to the key. Aim an
optical IR beam at the key so that the beam will reflect to a receiver
when the key is in the off position. When the reflected beam is
received, the low oil pressure warning light will be disabled. It
sounds complicated but I am sure that there are off the shelf parts
available to easily accomplish this. Perhaps someone knowledgeable in
solid state circuitry can help you.
Joe
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: oil pressure warn logic |
ROTFL ! I knew sooner or later somebody would come through with an elegant,
failsafe solution!
Ron
On Wed, May 7, 2008 at 11:32 AM, Joe wrote:
> Ron,
>
> Looking at the schematic that Bob K provided on Z-26, there are no unused
> contacts on the key switch. Connecting to the left or right mag wires is a
> bad idea because doing so might disable the magneto. Here is a suggestion:
> Tape a piece of reflective tape to the key. Aim an optical IR beam at the
> key so that the beam will reflect to a receiver when the key is in the off
> position. When the reflected beam is received, the low oil pressure warning
> light will be disabled. It sounds complicated but I am sure that there are
> off the shelf parts available to easily accomplish this. Perhaps someone
> knowledgeable in solid state circuitry can help you.
> Joe
>
________________________________________________________________________________
| Subject: | Re: oil pressure warn logic |
| From: | "Matt Prather" <mprather(at)spro.net> |
I little Rube Goldberg-ian, but I like it.. :)
A crude optical encoder..
Matt-
> Ron,
>
> Looking at the schematic that Bob K provided on Z-26, there are no unused
> contacts on the key switch. Connecting to the left or right mag wires is
> a bad idea because doing so might disable the magneto. Here is a
> suggestion: Tape a piece of reflective tape to the key. Aim an optical IR
> beam at the key so that the beam will reflect to a receiver when the key
> is in the off position. When the reflected beam is received, the low oil
> pressure warning light will be disabled. It sounds complicated but I am
> sure that there are off the shelf parts available to easily accomplish
> this. Perhaps someone knowledgeable in solid state circuitry can help
> you.
> Joe
________________________________________________________________________________
| Subject: | Re: AW: New HOBBS Idea |
| From: | "rampil" <ira.rampil(at)gmail.com> |
Hi LongG,
It may have been a show special price, but PSA is still worth a try at
http://www.psaenterprises.com/
I am using the little guy in car at the moment, trying to build some hours on it
;-)
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=181801#181801
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Z-19 Item Clarification |
>I have attached my electrical diagram. It was made with TurboCad Pro 14 and
>it's a .DWG. There was some issues getting some people to read it before,
>if anyone knows of a better, more universal format, let me know.
PDF is as close to a universal print format as you can get.
If you have Acrobat, you can print your CAD drawing to that.
If you don't have a pdf generator, goto
http://www.cutepdf.com/Products/CutePDF/writer.asp
and get CutePDF Writer. Be sure to read and follow
the installation requirements. Theres a conversion
utility you need too.
I've used these for years with excellent performance.
They're free for the downloading.
Bob. . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Fw: Torque Values |
>"urn:schemas-microsoft-com:vml" xmlns:o =
>"urn:schemas-microsoft-com:office:office" xmlns:w =
>"urn:schemas-microsoft-com:office:word" xmlns:st1 =
>"urn:schemas-microsoft-com:office:smarttags">
>
>----- Original Message -----
>From: <mailto:hammer408(at)comcast.net>Henry Trzeciakowski
>To: aeroelectric-list(at)matronics.com
>Sent: Sunday, May 04, 2008 10:15 AM
>Subject: Re: Torque Values
>
>Bob:
>
>I just can't find any info on what the torque values are for the large and
>small terminals on the Battery Contactor and Starter Contactor.
>
>Any assistance appreciated.
I hadn't forgotten you. I've been mulling over the value
of looking up and then citing 'optimum' torque values but
ultimately decided against it.
These are not structural joints. The main goal is to achieve
gas-tight connection to terminals. I've successfully
installed these critters for years on a lot of applications
and never used a torque wrench. Never observed a failure
that was related to fastener torque.
There's a nice bolt torque calculator you can reference
at:
http://www.futek.com/boltcalc.aspx
Use "custom" material entries (20KPSI copper isn't
in the calculator's data tables). Enter 15000 psi as
the proof strength for the bolt (stud) and
20000 psi as yield strength for the receptacle
(nut). The nut thickness for 5/16-18 is about
.30" so enter that as "length" of engagement.
The program will honk at you for not having sufficient
recommended engagement and then call 30 in-lb as being
a good value. You can repeat this exercise for other
fasteners by entering appropriate data.
By the way, it's a good practice to put a counter-
torque wrench on the inside nut of this style
of contactor . . .
http://www.aeroelectric.com/Pictures/Contactors/s701-1l.jpg
and apply anti-rotation force on it as you tighten
the top nut. But don't loose a lot of sleep over them.
Snug them up "purdy good" and they'll probably be fine.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Ben Westfall" <rv10(at)sinkrate.com> |
| Subject: | PMA-6000 intercom 28V install |
PS Engineering's PMA-6000 intercom has the following note:
"To reduce the amount of heat dissipated in the audio selector panel, when
used in a 28
Volt aircraft, it is required that the 15-Ohm, 15-Watt dropping resistor
(p/n 701-015-1501) be in-
stalled in series with the power input."
The install manual goes on to say "failure to do so will generate
unnecessary heat inside the unit and may void PS Engineering's warranty".
Does anyone have experience installing one of these units in a 28V
environment? Is the dropping resistor really required? The only reason I
ask is the local radio shops don't seem to know much about it which makes me
wonder if they ever used them. They all say they can order one but nobody
has one in stock.
-Ben Westfall
________________________________________________________________________________
| From: | Larry Rosen <LarryRosen(at)comcast.net> |
| Subject: | Re: Z-19 Item Clarification |
Attached is a pdf of the file.
Robert L. Nuckolls, III wrote:
>
>
>
>> I have attached my electrical diagram. It was made with TurboCad Pro
>> 14 and
>> it's a .DWG. There was some issues getting some people to read it
>> before,
>> if anyone knows of a better, more universal format, let me know.
>
> PDF is as close to a universal print format as you can get.
> If you have Acrobat, you can print your CAD drawing to that.
> If you don't have a pdf generator, goto
>
> http://www.cutepdf.com/Products/CutePDF/writer.asp
>
> and get CutePDF Writer. Be sure to read and follow
> the installation requirements. Theres a conversion
> utility you need too.
>
> I've used these for years with excellent performance.
> They're free for the downloading.
>
> Bob. . .
>
>
________________________________________________________________________________
| From: | "RALPH HOOVER" <hooverra(at)verizon.net> |
| Subject: | PMA-6000 intercom 28V install |
Ben,
Sounds like about 12 w or so of extra heat localized near the regulator
(probably not a switcher with this note) I would follow PS Engineering's
recommendation. Because some have ignored the advice and not installed the
resistor and it worked doesn't mitigate the long term effects of additional
heat. Most things electronic work better and last longer if kept cool.
Ralph Hoover
_____
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ben
Westfall
Sent: Wednesday, May 07, 2008 11:24 PM
Subject: AeroElectric-List: PMA-6000 intercom 28V install
PS Engineering's PMA-6000 intercom has the following note:
"To reduce the amount of heat dissipated in the audio selector panel, when
used in a 28
Volt aircraft, it is required that the 15-Ohm, 15-Watt dropping resistor
(p/n 701-015-1501) be in-
stalled in series with the power input."
The install manual goes on to say "failure to do so will generate
unnecessary heat inside the unit and may void PS Engineering's warranty".
Does anyone have experience installing one of these units in a 28V
environment? Is the dropping resistor really required? The only reason I
ask is the local radio shops don't seem to know much about it which makes me
wonder if they ever used them. They all say they can order one but nobody
has one in stock.
-Ben Westfall
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Architecture Review |
>Attached is a pdf of the file.
Re: AeroElectric-List: Z-19 Item Clarification
Hmmm. Perhaps there was some form of thread-creep
but the attached drawing has no resemblance to
Z-19. I'll have to let the List members work
on this. It's so far from the best I know how
to do, distilling it down to the simple-ideas
would take a significant amount of time . . .
a commodity I don't have in abundance right
now. Sorry.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Jerry Ricciotti" <gfr56(at)comcast.net> |
| Subject: | Z-13/8 AWG question |
Greetings
Referring to Z-13/8 diagram, the wire from the battery contactor to the
main power distribution bus does not have a AWG callout. Would I be
correct in assuming it should be 14 AWG (the same as battery contactor
to the Main Battery Bus)
Thanks Jerry
________________________________________________________________________________
| Subject: | Z-19 Item Clarification |
Thanks for converting Larry.
Scott, you broke the simplification rule, but not the experimental one.
Starting from the grip, wow that's a bit lazy :) Looks good, thanks for
posting. The always hot deal for the fuel pumps/EFI/ECU is not a bad
thing on these Subes. Do you have a layout of your panel switches?
Glenn
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Larry
Rosen
Sent: Thursday, May 08, 2008 6:56 AM
Subject: Re: AeroElectric-List: Z-19 Item Clarification
Attached is a pdf of the file.
Robert L. Nuckolls, III wrote:
>
>
>
>> I have attached my electrical diagram. It was made with TurboCad Pro
>> 14 and
>> it's a .DWG. There was some issues getting some people to read it
>> before,
>> if anyone knows of a better, more universal format, let me know.
>
> PDF is as close to a universal print format as you can get.
> If you have Acrobat, you can print your CAD drawing to that.
> If you don't have a pdf generator, goto
>
> http://www.cutepdf.com/Products/CutePDF/writer.asp
>
> and get CutePDF Writer. Be sure to read and follow
> the installation requirements. Theres a conversion
> utility you need too.
>
> I've used these for years with excellent performance.
> They're free for the downloading.
>
> Bob. . .
>
>
________________________________________________________________________________
| From: | "Scott R. Shook" <sshook(at)cox.net> |
| Subject: | Z-19 Item Clarification |
I am confused...Simplification rule starting from the grip? Are you talking
about my use of the infinity grips?
Scott R. Shook
RV-7A (Building)
N696JS (Reserved)
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
longg(at)pjm.com
Sent: Thursday, 08 May, 2008 09:16
Subject: RE: AeroElectric-List: Z-19 Item Clarification
Thanks for converting Larry.
Scott, you broke the simplification rule, but not the experimental one.
Starting from the grip, wow that's a bit lazy :) Looks good, thanks for
posting. The always hot deal for the fuel pumps/EFI/ECU is not a bad
thing on these Subes. Do you have a layout of your panel switches?
Glenn
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Larry
Rosen
Sent: Thursday, May 08, 2008 6:56 AM
Subject: Re: AeroElectric-List: Z-19 Item Clarification
Attached is a pdf of the file.
Robert L. Nuckolls, III wrote:
>
>
>
>> I have attached my electrical diagram. It was made with TurboCad Pro
>> 14 and
>> it's a .DWG. There was some issues getting some people to read it
>> before,
>> if anyone knows of a better, more universal format, let me know.
>
> PDF is as close to a universal print format as you can get.
> If you have Acrobat, you can print your CAD drawing to that.
> If you don't have a pdf generator, goto
>
> http://www.cutepdf.com/Products/CutePDF/writer.asp
>
> and get CutePDF Writer. Be sure to read and follow
> the installation requirements. Theres a conversion
> utility you need too.
>
> I've used these for years with excellent performance.
> They're free for the downloading.
>
> Bob. . .
>
>
________________________________________________________________________________
| From: | "Scott R. Shook" <sshook(at)cox.net> |
| Subject: | Architecture Review |
The design for power to the engine was from what Eggenfellner is
recommending and supporting. Power comes from the main buss to the engine
through the 4P3T switch. The 4P3T switch is to counter an alternator, a
relay failure, or exhaustion of the main battery.
If my alternator goes south:
1) Fly the Plane
2) Isolate the aux battery (aux batt switch off)
3) Find a close airport to land at.
4) Reduce non-essential electrical loads (AP, Radio, etc.) - Note I will
still have AHRS as both EFIS screens are battery backed up and I have
handheld backups (ICOM and GPS).
5) If I have still not landed after 30 minutes on the main battery - with
the flip of the 4P3T switch I still have the Aux battery to supply power to
keep the prop turning.
Please understand: I will not take any criticism personally. I would not
have submitted this to the list had I not expected corrections.
I don't want God beating the FAA to the crash site. The more eyes the
better.
There are already two suggestions from off-list responses that I have had
that I will likely incorporate - Remove Avionics Mater - move the momentary
push to start to the panel.
Scott R. Shook
RV-7A (Building)
N696JS (Reserved)
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Thursday, 08 May, 2008 07:47
Subject: AeroElectric-List: Architecture Review
>Attached is a pdf of the file.
Re: AeroElectric-List: Z-19 Item Clarification
Hmmm. Perhaps there was some form of thread-creep
but the attached drawing has no resemblance to
Z-19. I'll have to let the List members work
on this. It's so far from the best I know how
to do, distilling it down to the simple-ideas
would take a significant amount of time . . .
a commodity I don't have in abundance right
now. Sorry.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: Z-19 Item Clarification |
FWIW you might consider that you simply don't have the oil pressure
issues that air cooled engines have with single grade oil. I run 5W50
synthetic and I pretty much ignore the oil pressure just like most car
drivers. If it doesn't come up or if it goes out of limits, the EIS will
bring it to my attention. The chances of a secondary failure where the
EIS would be helpful, at the same time as an alternator failure, have
got to to be very small. Keeping it simple has advantages. Do you really
care if the EIS works after an alternator failure? Will it help you fly
the airplane or just be a distraction?
Ken
Allen Fulmer wrote:
>snip
> 4. One of the things I am wrestling with is how to power the engine
> instruments (GRT EIS4000 in my case; AFS3500 EMS in yours) so ONLY it comes
> on when the Engine Bus Master Switch is placed in either ON position. (To
> check oil pressure light working and to see the oil pressure come up when
> engine starts.) That may require an Avionics Switch/Relay since the starter
> requires/prefers to have both Battery Contactors energized. Still thinking
> about that issue.
>
________________________________________________________________________________
| From: | "Allen Fulmer" <afulmer(at)charter.net> |
| Subject: | Z-19 Item Clarification |
Thanks Ken,
One of the reasons for turning on the EIS before starting the engine is to
make sure the oil pressure sensor DOES work like it is supposed to. But you
make a good point. Maybe the light could be checked when shutting DOWN the
engine before the EIS is turned OFF? Thoughts?
Allen
>>>-----Original Message-----
>>>From: owner-aeroelectric-list-server(at)matronics.com
>>>[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Ken
>>>Sent: Thursday, May 08, 2008 4:03 PM
>>>To: aeroelectric-list(at)matronics.com
>>>Subject: Re: AeroElectric-List: Z-19 Item Clarification
>>>
>>>
>>>
>>>FWIW you might consider that you simply don't have the oil pressure
>>>issues that air cooled engines have with single grade oil. I
>>>run 5W50
>>>synthetic and I pretty much ignore the oil pressure just
>>>like most car
>>>drivers. If it doesn't come up or if it goes out of limits,
>>>the EIS will
>>>bring it to my attention. The chances of a secondary failure
>>>where the
>>>EIS would be helpful, at the same time as an alternator
>>>failure, have
>>>got to to be very small. Keeping it simple has advantages.
>>>Do you really
>>>care if the EIS works after an alternator failure? Will it
>>>help you fly
>>>the airplane or just be a distraction?
>>>Ken
>>>
>>>Allen Fulmer wrote:
>>>>snip
>>>> 4. One of the things I am wrestling with is how to power the engine
>>>> instruments (GRT EIS4000 in my case; AFS3500 EMS in yours)
>>>so ONLY it comes
>>>> on when the Engine Bus Master Switch is placed in either
>>>ON position. (To
>>>> check oil pressure light working and to see the oil
>>>pressure come up when
>>>> engine starts.) That may require an Avionics Switch/Relay
>>>since the starter
>>>> requires/prefers to have both Battery Contactors
>>>energized. Still thinking
>>>> about that issue.
>>>>
>>>
>>>
>>>
>>>
>>>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Z-13/8 AWG question |
>Greetings
>Referring to Z-13/8 diagram, the wire from the battery contactor to the
>main power distribution bus does not have a AWG callout. Would I be
>correct in assuming it should be 14 AWG (the same as battery contactor to
>the Main Battery Bus)
Yes, all wires in series with each other are generally the
same guage.
Bob . . .
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: Z-19 Item Clarification |
Allen
My EIS comes on any time the master switch is on so it is on before
startup. However I elected not to provide any other power source for it
so it does go dead if I turn off the master switch.
The warning light flashes for everything outside of spec which means you
can cancel them one at a time to confirm they are working. However I
normally just start the engine which removes all the warnings except low
coolant pressure.
At shutdown the warnings come back on for low voltage and low oil
pressure which can again be canceled one at a time as you suggest.
However if the oil pressure indicated normal at any time while the
engine was running, it is very unlikely that the low pressure warning
will not work from the EIS. You can also set the low oil pressure
warning such that it will come on at slow idle just before shutdown (if
the oil is up to temperature). In my case I also wired a small light to
the low pressure switch that was already installed in my stock engine.
The engine is my own conversion and I run a modified Z-14 architecture
with two small alternators and two very small 8AH batteries. The system
actually weighs less than many single alternator single battery
installations.
Ken
Allen Fulmer wrote:
>
> Thanks Ken,
>
> One of the reasons for turning on the EIS before starting the engine is to
> make sure the oil pressure sensor DOES work like it is supposed to. But you
> make a good point. Maybe the light could be checked when shutting DOWN the
> engine before the EIS is turned OFF? Thoughts?
>
> Allen
>
>>>> -----Original Message-----
>>>> From: owner-aeroelectric-list-server(at)matronics.com
>>>> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Ken
>>>> Sent: Thursday, May 08, 2008 4:03 PM
>>>> To: aeroelectric-list(at)matronics.com
>>>> Subject: Re: AeroElectric-List: Z-19 Item Clarification
>>>>
>>>>
>>>>
>>>> FWIW you might consider that you simply don't have the oil pressure
>>>> issues that air cooled engines have with single grade oil. I
>>>> run 5W50
>>>> synthetic and I pretty much ignore the oil pressure just
>>>> like most car
>>>> drivers. If it doesn't come up or if it goes out of limits,
>>>> the EIS will
>>>> bring it to my attention. The chances of a secondary failure
>>>> where the
>>>> EIS would be helpful, at the same time as an alternator
>>>> failure, have
>>>> got to to be very small. Keeping it simple has advantages.
>>>> Do you really
>>>> care if the EIS works after an alternator failure? Will it
>>>> help you fly
>>>> the airplane or just be a distraction?
>>>> Ken
>>>>
>>>> Allen Fulmer wrote:
>>>>> snip
>>>>> 4. One of the things I am wrestling with is how to power the engine
>>>>> instruments (GRT EIS4000 in my case; AFS3500 EMS in yours)
>>>> so ONLY it comes
>>>>> on when the Engine Bus Master Switch is placed in either
>>>> ON position. (To
>>>>> check oil pressure light working and to see the oil
>>>> pressure come up when
>>>>> engine starts.) That may require an Avionics Switch/Relay
>>>> since the starter
>>>>> requires/prefers to have both Battery Contactors
>>>> energized. Still thinking
>>>>> about that issue.
>>>>>
>>>>
>>>>
>>>>
>>>>
>
>
>
>
>
________________________________________________________________________________
| Subject: | Re: PMA-6000 intercom 28V install |
| From: | Etienne Phillips <etienne.phillips(at)gmail.com> |
Here's my suggestion... (Hello for the first time everybody, by the
way):
What about using a DC-DC converter? Using a resistor, the extra
energy provided by the 28V is simply dissipated as heat... Using a DC-
DC converter, the voltage is usually dropped using a tiny switching-
type power supply.
Doing the Maths:
Worst case is that the 15W resistor is being driven to the limit of 15W
Using P=I^2 * R
yields a current draw by the intercom of 1A
There is a fair variety of 14V switching voltage regulators (or DC-DC
converters), eg: PT78ST114 from Texas Instruments (spec sheet: http://
www.ti.com/lit/gpn/pt78st114 ) this one has a 90%+ efficiency, and is
a single component with 3 legs: In, Out and Ground... In connects to
28V, Out connects to the intercom power in, and the intercom's
ground, the voltage regulator's ground and panel ground connect
together. It's also advised to put a smoothing cap on either side, so
I guess the total component count is actually 3 parts.
No heat, no power wastage, and ripple- and spike-free power for the
intercom...
Disadvantage: black box between power and intercom that could fail.
Risk: Highly unlikely, these things have all sorts of built in
protection against heat, short-circuit, open circuit, over-current
draw, etc...
Anyway, it's just an intercom ;-)
What do you guys think?
Etienne
On 08 May 2008, at 12:59 PM, RALPH HOOVER wrote:
> Ben,
> Sounds like about 12 w or so of extra heat localized near the
> regulator (probably not a switcher with this note) I would follow
> PS Engineering=92s recommendation. Because some have ignored the
> advice and not installed the resistor and it worked doesn=92t
> mitigate the long term effects of additional heat. Most things
> electronic work better and last longer if kept cool.
>
> Ralph Hoover
>
>
> From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-
> aeroelectric-list-server(at)matronics.com] On Behalf Of Ben Westfall
> Sent: Wednesday, May 07, 2008 11:24 PM
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: PMA-6000 intercom 28V install
>
> PS Engineering=92s PMA-6000 intercom has the following note:
>
> =93To reduce the amount of heat dissipated in the audio selector
> panel, when used in a 28
> Volt aircraft, it is required that the 15-Ohm, 15-Watt dropping
> resistor (p/n 701-015-1501) be in-
> stalled in series with the power input.=94
>
> The install manual goes on to say =93failure to do so will generate
> unnecessary heat inside the unit and may void PS Engineering=92s
> warranty=94. Does anyone have experience installing one of these
> units in a 28V environment? Is the dropping resistor really
> required? The only reason I ask is the local radio shops don=92t
> seem to know much about it which makes me wonder if they ever used
> them. They all say they can order one but nobody has one in stock.
>
> -Ben Westfall
>
>
> http://www.matronics.com/contribution
>
>
________________________________________________________________________________
| From: | "RALPH HOOVER" <hooverra(at)verizon.net> |
| Subject: | PMA-6000 intercom 28V install |
Etienne,
I suspect that PS engineering is using an analog regulator for noise
concerns (cost can figure in as well). Use care inserting a switcher without
properly considering the noise concern. A switcher would certainly allow for
a wide input voltage range without a lot of heat. Not a show stopper but a
design challenge to address.
This is just my take I have no knowledge of PS Engineering's design or the
process and decisions they have taken to arrive at their design. I have used
a switcher for my ANR power supply I'll soon find out if I have any issues!
Ralph & Laura Hoover
RV7A N527LR
_____
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Etienne
Phillips
Sent: Friday, May 09, 2008 2:58 AM
Subject: Re: AeroElectric-List: PMA-6000 intercom 28V install
Here's my suggestion... (Hello for the first time everybody, by the way):
What about using a DC-DC converter? Using a resistor, the extra energy
provided by the 28V is simply dissipated as heat... Using a DC-DC converter,
the voltage is usually dropped using a tiny switching-type power supply.
Doing the Maths:
Worst case is that the 15W resistor is being driven to the limit of 15W
Using P=I^2 * R
yields a current draw by the intercom of 1A
There is a fair variety of 14V switching voltage regulators (or DC-DC
converters), eg: PT78ST114 from Texas Instruments (spec sheet:
http://www.ti.com/lit/gpn/pt78st114 ) this one has a 90%+ efficiency, and is
a single component with 3 legs: In, Out and Ground... In connects to 28V,
Out connects to the intercom power in, and the intercom's ground, the
voltage regulator's ground and panel ground connect together. It's also
advised to put a smoothing cap on either side, so I guess the total
component count is actually 3 parts.
No heat, no power wastage, and ripple- and spike-free power for the
intercom...
Disadvantage: black box between power and intercom that could fail.
Risk: Highly unlikely, these things have all sorts of built in protection
against heat, short-circuit, open circuit, over-current draw, etc...
Anyway, it's just an intercom ;-)
What do you guys think?
Etienne
On 08 May 2008, at 12:59 PM, RALPH HOOVER wrote:
Ben,
Sounds like about 12 w or so of extra heat localized near the regulator
(probably not a switcher with this note) I would follow PS Engineering's
recommendation. Because some have ignored the advice and not installed the
resistor and it worked doesn't mitigate the long term effects of additional
heat. Most things electronic work better and last longer if kept cool.
Ralph Hoover
_____
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ben
Westfall
Sent: Wednesday, May 07, 2008 11:24 PM
Subject: AeroElectric-List: PMA-6000 intercom 28V install
PS Engineering's PMA-6000 intercom has the following note:
"To reduce the amount of heat dissipated in the audio selector panel, when
used in a 28
Volt aircraft, it is required that the 15-Ohm, 15-Watt dropping resistor
(p/n 701-015-1501) be in-
stalled in series with the power input."
The install manual goes on to say "failure to do so will generate
unnecessary heat inside the unit and may void PS Engineering's warranty".
Does anyone have experience installing one of these units in a 28V
environment? Is the dropping resistor really required? The only reason I
ask is the local radio shops don't seem to know much about it which makes me
wonder if they ever used them. They all say they can order one but nobody
has one in stock.
-Ben Westfall
<http://www.matronics.com/contribution>
http://www.matronics.com/contribution
________________________________________________________________________________
| From: | "sam(at)fr8dog.net" <sam.marlow(at)adelphia.net> |
| Subject: | Re: PMA-6000 intercom 28V install |
Hi Etienne,
I'm not installing an intercom,but I do have the need to reduce bus voltage to
a stable 4.8 to 5.0 volts for instrumentation at times. But I was wondering why
you chose the PT78ST114S,isn't that 13.9 volt max out? Wouldn't the PT78ST05S
work for 5.0v out? Or am I reading the chart incorrectly?
Thanks,
Sam Marlow
---- Etienne Phillips wrote:
============
Here's my suggestion... (Hello for the first time everybody, by the
way):
What about using a DC-DC converter? Using a resistor, the extra
energy provided by the 28V is simply dissipated as heat... Using a DC-
DC converter, the voltage is usually dropped using a tiny switching-
type power supply.
Doing the Maths:
Worst case is that the 15W resistor is being driven to the limit of 15W
Using P=I^2 * R
yields a current draw by the intercom of 1A
There is a fair variety of 14V switching voltage regulators (or DC-DC
converters), eg: PT78ST114 from Texas Instruments (spec sheet: http://
www.ti.com/lit/gpn/pt78st114 ) this one has a 90%+ efficiency, and is
a single component with 3 legs: In, Out and Ground... In connects to
28V, Out connects to the intercom power in, and the intercom's
ground, the voltage regulator's ground and panel ground connect
together. It's also advised to put a smoothing cap on either side, so
I guess the total component count is actually 3 parts.
No heat, no power wastage, and ripple- and spike-free power for the
intercom...
Disadvantage: black box between power and intercom that could fail.
Risk: Highly unlikely, these things have all sorts of built in
protection against heat, short-circuit, open circuit, over-current
draw, etc...
Anyway, it's just an intercom ;-)
What do you guys think?
Etienne
On 08 May 2008, at 12:59 PM, RALPH HOOVER wrote:
> Ben,
> Sounds like about 12 w or so of extra heat localized near the
> regulator (probably not a switcher with this note) I would follow
> PS Engineerings recommendation. Because some have ignored the
> advice and not installed the resistor and it worked doesnt
> mitigate the long term effects of additional heat. Most things
> electronic work better and last longer if kept cool.
>
> Ralph Hoover
>
>
> From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-
> aeroelectric-list-server(at)matronics.com] On Behalf Of Ben Westfall
> Sent: Wednesday, May 07, 2008 11:24 PM
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: PMA-6000 intercom 28V install
>
> PS Engineerings PMA-6000 intercom has the following note:
>
> To reduce the amount of heat dissipated in the audio selector
> panel, when used in a 28
> Volt aircraft, it is required that the 15-Ohm, 15-Watt dropping
> resistor (p/n 701-015-1501) be in-
> stalled in series with the power input.
>
> The install manual goes on to say failure to do so will generate
> unnecessary heat inside the unit and may void PS Engineerings
> warranty. Does anyone have experience installing one of these
> units in a 28V environment? Is the dropping resistor really
> required? The only reason I ask is the local radio shops dont
> seem to know much about it which makes me wonder if they ever used
> them. They all say they can order one but nobody has one in stock.
>
> -Ben Westfall
>
>
> http://www.matronics.com/contribution
>
>
________________________________________________________________________________
| Subject: | Z13/8, max. E-bus and self-excitation |
| From: | "Camillo" <ungaritrasatti(at)alice.it> |
Hi. I read all the book, surfed the forum and still have a couple of questions.
1) Is there any reason why I cannot put almost every load on E-bus and then switch
what's not necessary off via breakers? I mean, if battery contactor fails,
I could not use all loads on main bus. If main alternator/battery contactor fails,
I can select what I need to remain under 8/10 amp.
2) Is Z25 self excitation mode utility needed in case of a battery short?
Thank-you.
Camillo
RV9A
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182144#182144
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Z13/8, max. E-bus and self-excitation |
>
>Hi. I read all the book, surfed the forum and still have a couple of
>questions.
>
>1) Is there any reason why I cannot put almost every load on E-bus and
>then switch what's not necessary off via breakers? I mean, if battery
>contactor fails, I could not use all loads on main bus. If main
>alternator/battery contactor fails, I can select what I need to remain
>under 8/10 amp.
Sure . . . you can do that. Why would you want to?
The point of the e-bus is to maximize utilization of a
limited resource of energy (battery) during alternator
out operations with a minimum of pilot work load (minimum
risk of doing something undesirable under stressful
conditions) and dual feedpaths for power.
Obviously, there are countless combinations of architecture,
bus loading and "plans-b" one could craft for their
project. All combinations would function as designed.
The questions to be asked and answered is what
benefits are derived by departing from a repeatable
experiment where design goals have been debated and
refined for over a decade?
In other words, what shortcoming do you perceive in Z13/8
as published. What design goals do you have that are not
addressed by Z13/8? Perhaps Z12 is a better fit for
you.
>2) Is Z25 self excitation mode utility needed in case of a battery short?
No, in case the battery is not available . . . I.e. disconnected.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| From: | "Allen Fulmer" <afulmer(at)charter.net> |
| Subject: | Z-19 Item Clarification |
Thanks Ken,
If your panel contains EFIS display units, are they on when your "master
switch" is turned on? Keeping them off until the engine is started is my
desire. I think BobN says it is not an issue with modern day electronics
but I seem to remember that GRT (at least) recommends that you not expose
the display units to the potential voltage drop during engine start.
(Actually, I seriously doubt starting the Subaru with it's geared starter is
going to create much of a drop but . . ..)
Allen
>>>-----Original Message-----
>>>From: owner-aeroelectric-list-server(at)matronics.com
>>>[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Ken
>>>Sent: Thursday, May 08, 2008 9:33 PM
>>>To: aeroelectric-list(at)matronics.com
>>>Subject: Re: AeroElectric-List: Z-19 Item Clarification
>>>
>>>
>>>
>>>Allen
>>>
>>>My EIS comes on any time the master switch is on so it is on before
>>>startup. However I elected not to provide any other power
>>>source for it
>>>so it does go dead if I turn off the master switch.
>>>
>>>The warning light flashes for everything outside of spec
>>>which means you
>>>can cancel them one at a time to confirm they are working. However I
>>>normally just start the engine which removes all the
>>>warnings except low
>>>coolant pressure.
>>>
>>>At shutdown the warnings come back on for low voltage and low oil
>>>pressure which can again be canceled one at a time as you suggest.
>>>However if the oil pressure indicated normal at any time while the
>>>engine was running, it is very unlikely that the low
>>>pressure warning
>>>will not work from the EIS. You can also set the low oil pressure
>>>warning such that it will come on at slow idle just before
>>>shutdown (if
>>>the oil is up to temperature). In my case I also wired a
>>>small light to
>>>the low pressure switch that was already installed in my
>>>stock engine.
>>>The engine is my own conversion and I run a modified Z-14
>>>architecture
>>>with two small alternators and two very small 8AH batteries.
>>>The system
>>>actually weighs less than many single alternator single battery
>>>installations.
>>>Ken
>>>
>>>
>>>Allen Fulmer wrote:
>>>
>>>>
>>>> Thanks Ken,
>>>>
>>>> One of the reasons for turning on the EIS before starting
>>>the engine is to
>>>> make sure the oil pressure sensor DOES work like it is
>>>supposed to. But you
>>>> make a good point. Maybe the light could be checked when
>>>shutting DOWN the
>>>> engine before the EIS is turned OFF? Thoughts?
>>>>
>>>> Allen
>>>>
>>>>>>> -----Original Message-----
>>>>>>> From: owner-aeroelectric-list-server(at)matronics.com
>>>>>>> [mailto:owner-aeroelectric-list-server(at)matronics.com]On
>>>Behalf Of Ken
>>>>>>> Sent: Thursday, May 08, 2008 4:03 PM
>>>>>>> To: aeroelectric-list(at)matronics.com
>>>>>>> Subject: Re: AeroElectric-List: Z-19 Item Clarification
>>>>>>>
>>>>>>>
>>>
>>>>>>>
>>>>>>> FWIW you might consider that you simply don't have the
>>>oil pressure
>>>>>>> issues that air cooled engines have with single grade oil. I
>>>>>>> run 5W50
>>>>>>> synthetic and I pretty much ignore the oil pressure just
>>>>>>> like most car
>>>>>>> drivers. If it doesn't come up or if it goes out of limits,
>>>>>>> the EIS will
>>>>>>> bring it to my attention. The chances of a secondary failure
>>>>>>> where the
>>>>>>> EIS would be helpful, at the same time as an alternator
>>>>>>> failure, have
>>>>>>> got to to be very small. Keeping it simple has advantages.
>>>>>>> Do you really
>>>>>>> care if the EIS works after an alternator failure? Will it
>>>>>>> help you fly
>>>>>>> the airplane or just be a distraction?
>>>>>>> Ken
>>>>>>>
>>>>>>> Allen Fulmer wrote:
>>>>>>>> snip
>>>>>>>> 4. One of the things I am wrestling with is how to
>>>power the engine
>>>>>>>> instruments (GRT EIS4000 in my case; AFS3500 EMS in yours)
>>>>>>> so ONLY it comes
>>>>>>>> on when the Engine Bus Master Switch is placed in either
>>>>>>> ON position. (To
>>>>>>>> check oil pressure light working and to see the oil
>>>>>>> pressure come up when
>>>>>>>> engine starts.) That may require an Avionics Switch/Relay
>>>>>>> since the starter
>>>>>>>> requires/prefers to have both Battery Contactors
>>>>>>> energized. Still thinking
>>>>>>>> about that issue.
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>
________________________________________________________________________________
| Subject: | Re: Z-19 Item Clarification |
| From: | "Mark Sletten" <marknlisa(at)hometel.com> |
sshook(at)cox.net wrote:
> For my Z19/Egg Hybrid wiring, I used all of Jan's recommendations for supplying
electrical power to the engine ECU, prop, and fuel pumps.--
Ok, I'll be the first to bite... why run power to all critical engine components
thru a single point of failure, specifically the four-pole switch? While you
have redundant sources feeding redundant poles on the feed side of the switch,
the failure of a single pole on the feed side of the switch (bad connection,
poor crimp, broken wire, etc.) results in engine shut down.
Additionally, you have both fuel pumps feeding off a single pole on the switch.
This seems like a single-point of failure added to a single-point of failure.
If this one pole of the switch fails you lose both fuel pumps.
In my mind, the whole point of redundant power supplies is to avoid single points
of failure.
Regards,
--------
Mark Sletten
Legacy FG N828LM
http://www.legacyfgbuilder.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182183#182183
________________________________________________________________________________
| From: | "Scott R. Shook" <sshook(at)cox.net> |
| Subject: | Re: Z-19 Item Clarification |
I hear what you are saying with the 4P3T switch. I just don't see any other
alternatives to switching bus power while still staying within the
recommendations/requirements of Eggenfellner.
Certainly, if someone has a suggestion or recommendation for me - I am
always ready to hear it.
Eventually, all roads in our redundant electrical systems lead to a single
point of failure - the power wire for the component we are powering. That
will always be a single point of failure as I do not know of many components
that have independent, redundant power sources.
Scott R. Shook
RV-7A (Building)
N696JS (Reserved)
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Mark
Sletten
Sent: Friday, 09 May, 2008 08:56
Subject: AeroElectric-List: Re: Z-19 Item Clarification
sshook(at)cox.net wrote:
> For my Z19/Egg Hybrid wiring, I used all of Jan's recommendations for
supplying electrical power to the engine ECU, prop, and fuel pumps.--
Ok, I'll be the first to bite... why run power to all critical engine
components thru a single point of failure, specifically the four-pole
switch? While you have redundant sources feeding redundant poles on the feed
side of the switch, the failure of a single pole on the feed side of the
switch (bad connection, poor crimp, broken wire, etc.) results in engine
shut down.
Additionally, you have both fuel pumps feeding off a single pole on the
switch. This seems like a single-point of failure added to a single-point of
failure. If this one pole of the switch fails you lose both fuel pumps.
In my mind, the whole point of redundant power supplies is to avoid single
points of failure.
Regards,
--------
Mark Sletten
Legacy FG N828LM
http://www.legacyfgbuilder.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182183#182183
________________________________________________________________________________
| From: | "Allen Fulmer" <afulmer(at)charter.net> |
| Subject: | Re: Z-19 Item Clarification |
Mark and all interested in the Z19/Eggenfellner Subaru electrical system
design discussion:
See if this link works to the thread titled: "Diode verses Switches 101"
http://forums.matronics.com/viewtopic.php?p=169493#169493
Allen Fulmer
>>>-----Original Message-----
>>>From: owner-aeroelectric-list-server(at)matronics.com
>>>[mailto:owner-aeroelectric-list-server(at)matronics.com]On
>>>Behalf Of Mark
>>>Sletten
>>>Sent: Friday, May 09, 2008 10:56 AM
>>>To: aeroelectric-list(at)matronics.com
>>>Subject: AeroElectric-List: Re: Z-19 Item Clarification
>>>
>>>
>>>
>>>
>>>
>>>sshook(at)cox.net wrote:
>>>> For my Z19/Egg Hybrid wiring, I used all of Jan's
>>>recommendations for supplying electrical power to the engine
>>>ECU, prop, and fuel pumps.--
>>>
>>>
>>>Ok, I'll be the first to bite... why run power to all
>>>critical engine components thru a single point of failure,
>>>specifically the four-pole switch? While you have redundant
>>>sources feeding redundant poles on the feed side of the
>>>switch, the failure of a single pole on the feed side of the
>>>switch (bad connection, poor crimp, broken wire, etc.)
>>>results in engine shut down.
>>>
>>>Additionally, you have both fuel pumps feeding off a single
>>>pole on the switch. This seems like a single-point of
>>>failure added to a single-point of failure. If this one pole
>>>of the switch fails you lose both fuel pumps.
>>>
>>>In my mind, the whole point of redundant power supplies is
>>>to avoid single points of failure.
>>>
>>>Regards,
>>>
>>>--------
>>>Mark Sletten
>>>Legacy FG N828LM
>>>http://www.legacyfgbuilder.com
>>>
>>>
>>>
>>>
>>>Read this topic online here:
>>>
>>>http://forums.matronics.com/viewtopic.php?p=182183#182183
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
________________________________________________________________________________
| Subject: | Re: Z13/8, max. E-bus and self-excitation |
| From: | "Camillo" <ungaritrasatti(at)alice.it> |
> Sure . . . you can do that. Why would you want to?
> The point of the e-bus is to maximize utilization of a
> limited resource of energy (battery) during alternator
> out operations with a minimum of pilot work load (minimum
> risk of doing something undesirable under stressful
> conditions) and dual feedpaths for power.
Among the others instruments, I'm planning a Dynon D10A, a GPS and an ADI, all
with internal batteries and I would like to disconnect them from airplane power
to lower aux. alternator load in case of primary alternator failure. But, I
still would be able to use plane power for them, if necessary. I understand the
pilot work stress came from switching each one off separately, but I plan to
mark the three said breakers in yellow in the CB panel and to make a remind above
the main alt. warning light (i.e.: in case of failure, switch off bks. x,y,z).
In addition, I'm planning to do IFR and I would not like to have NAV/COMM
off (for a mayday or a radar assistance to home). So, if I have to keep at least
this things on the E-bus, I thought it would be better to have all on it.
> Obviously, there are countless combinations of architecture,
> bus loading and "plans-b" one could craft for their
> project. All combinations would function as designed.
> The questions to be asked and answered is what
> benefits are derived by departing from a repeatable
> experiment where design goals have been debated and
> refined for over a decade?
> In other words, what shortcoming do you perceive in Z13/8
> as published. What design goals do you have that are not
> addressed by Z13/8? Perhaps Z12 is a better fit for
> you.
I chose Z13/8 because I understood that in Z12 SD-20 would not work without a battery
and adding a second battery would have not been a great idea, since an
RV9 is not a Boeing (actually, the idea was to pass to Z-14, since the step would
have been short...the Boeing relates to this). So, I thaught SD8, even if
less powerful, would have been a better choice in terms of safety (cost and weight).
Also, I can't say if Z12 could be adapted to receive SD-8. If yes, I anyway
doubt it would be good choice: the battery contactor will take 1 amp. off!.
In such event, will it work with SB-1 (great capability having it...) or shall
it be activated manually as per Z13/8?
At the end of this, I may guess options are:
- Z13/8 as I said;
- Z12 (L40 + SD20) with Z35 to supply power to secondary alternator.
> No, in case the battery is not available . . . I.e. disconnected.
Sorry...I may need a fourth reading of the book here. If battery is shorted I would
have no alternative than using analogic instrument and internally powered
electronics one. Isn't it?
Thank-you again.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182216#182216
________________________________________________________________________________
| From: | Harley <harley(at)AgelessWings.com> |
| Subject: | Re: Z-19 Item Clarification |
>>I do not know of many components that have independent, redundant
power sources.<<
The P-Mag for one...electrically, anyway
Harley
------------------------------------------------------------------------
Scott R. Shook wrote:
>
> I hear what you are saying with the 4P3T switch. I just don't see any other
> alternatives to switching bus power while still staying within the
> recommendations/requirements of Eggenfellner.
>
> Certainly, if someone has a suggestion or recommendation for me - I am
> always ready to hear it.
>
> Eventually, all roads in our redundant electrical systems lead to a single
> point of failure - the power wire for the component we are powering. That
> will always be a single point of failure as I do not know of many components
> that have independent, redundant power sources.
>
>
> Scott R. Shook
> RV-7A (Building)
> N696JS (Reserved)
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Mark
> Sletten
> Sent: Friday, 09 May, 2008 08:56
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Re: Z-19 Item Clarification
>
>
>
>
> sshook(at)cox.net wrote:
>
>> For my Z19/Egg Hybrid wiring, I used all of Jan's recommendations for
>>
> supplying electrical power to the engine ECU, prop, and fuel pumps.--
>
>
> Ok, I'll be the first to bite... why run power to all critical engine
> components thru a single point of failure, specifically the four-pole
> switch? While you have redundant sources feeding redundant poles on the feed
> side of the switch, the failure of a single pole on the feed side of the
> switch (bad connection, poor crimp, broken wire, etc.) results in engine
> shut down.
>
> Additionally, you have both fuel pumps feeding off a single pole on the
> switch. This seems like a single-point of failure added to a single-point of
> failure. If this one pole of the switch fails you lose both fuel pumps.
>
> In my mind, the whole point of redundant power supplies is to avoid single
> points of failure.
>
> Regards,
>
> --------
> Mark Sletten
> Legacy FG N828LM
> http://www.legacyfgbuilder.com
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=182183#182183
>
>
>
> ------------------------------------------------------------------------
>
>
> Agelesswings certifies that no virus is in this incoming message.
> Checked by AVG.
>
________________________________________________________________________________
| Subject: | Re: Z13/8, max. E-bus and self-excitation |
| From: | "Matt Prather" <mprather(at)spro.net> |
>
>
>
snip
> Among the others instruments, I'm planning a Dynon D10A, a GPS and an ADI,
> all with internal batteries and I would like to disconnect them from
> airplane power to lower aux. alternator load in case of primary alternator
> failure. But, I still would be able to use plane power for them, if
> necessary.
I wonder how much power these items will draw when the main bus voltage
drops after an alternator failure. It might be slick if they'd switch to
internal battery if the bus voltage drops down to ~12V.. Not terribly
difficult to accomplish.
Regards,
Matt-
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: Z-19 Item Clarification |
Hello Allen
No I do not have an EFIS, just a six pack of conventional flight
instruments on my bird.
Computers make wonderful monitoring tools though and my Grand Rapids EIS
(engine instruments only) is always powered during start up. It does not
reboot as far as I know but it wouldn't matter anyway as it comes up
pretty much instantly when turned on. It has survived several hundred
startups so far ;) Thanks to the crowbar overvoltage module, it has
also survived a voltage regulator failure that drove the voltage up.
Ken
Allen Fulmer wrote:
>
> Thanks Ken,
>
> If your panel contains EFIS display units, are they on when your "master
> switch" is turned on? Keeping them off until the engine is started is my
> desire. I think BobN says it is not an issue with modern day electronics
> but I seem to remember that GRT (at least) recommends that you not expose
> the display units to the potential voltage drop during engine start.
> (Actually, I seriously doubt starting the Subaru with it's geared starter is
> going to create much of a drop but . . ..)
>
> Allen
>
________________________________________________________________________________
| From: | Etienne Phillips <etienne.phillips(at)gmail.com> |
| Subject: | Re: PMA-6000 intercom 28V install |
On 09 May 2008, at 3:10 PM, sam(at)fr8dog.net wrote:
> Hi Etienne,
> I'm not installing an intercom,but I do have the need to reduce bus
> voltage to a stable 4.8 to 5.0 volts for instrumentation at times.
> But I was wondering why you chose the PT78ST114S,isn't that 13.9
> volt max out? Wouldn't the PT78ST05S work for 5.0v out? Or am I
> reading the chart incorrectly?
> Thanks,
> Sam Marlow
Hi Sam
I suggested that one, because I presumed that the intercom (as per
the topic ;-) ) would run very comfortably on 14V. If you need 5V,
then I'd suggest a PT78ST105V, assuming your entire bus doesn't
require more than 1.5A, and as per Ralf Hoover's comment, make sure
that your instruments can handle having a switch-mode supply up stream.
The reason I like this family of switchers though is because they
have a fairly high internal frequency of 650kHz, which can be
filtered out quite easily using the smoothing caps. However, there is
still a chance of that noise getting through into the instrument, so
some testing is probably in order...
Hope that helps :-)
Etienne
P.S. For my last response, I made a mistake with the part number - it
should read PT78ST114V, and not PT78ST114S - S is for surface
mount, and V is for vertical mount!
________________________________________________________________________________
| Subject: | Re: Z-19 Item Clarification |
| From: | "Mark Sletten" <marknlisa(at)hometel.com> |
sshook(at)cox.net wrote:
> I hear what you are saying with the 4P3T switch. I just don't see any other
alternatives to switching bus power while still staying within the recommendations/requirements
of Eggenfellner.
I've read the Eggenfellner install manual. There IS a schematic depicting what
the manual refers to as "one way to wire your system" using the switch to which
you refer. I couldn't find anything stating the switch as a "requirement." As
far as I can see, the ONLY benefit this switch provides is the ability to switch
between power supplies with a single switch.
Other than the drawing in the manual, which specific recommendation(s) from Eggenfellner
require you to incorporate a single point of failure in your electrical
system? Maybe a better question might be how has Eggenfellner justified the
recommendation(s) you feel compelled to follow?
sshook(at)cox.net wrote:
> Eventually, all roads in our redundant electrical systems lead to a single point
of failure - the power wire for the component we are powering. That will
always be a single point of failure as I do not know of many components that have
independent, redundant power sources.
Comparing a single, unbroken wire connected at either end with a switch incorporating
12 external connecting points and a multitude of moving parts manipulating
several internal contacts is a bit of a stretch...
Even if you are convinced of the invincibility of the switch, what design philosophy
drives connecting both fuel pumps to a single pole of the switch?
Regards,
--------
Mark Sletten
Legacy FG N828LM
http://www.legacyfgbuilder.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182437#182437
________________________________________________________________________________
| From: | "Henry Trzeciakowski" <hammer408(at)comcast.net> |
| Subject: | Re: EFIS Battery Back-up Power |
Bob:
I'm planning to install a AFS 3400 with it's own internal battery
back-up...... fused it to my Main Bus..
How I visualize: main alternator goes off line, I kill the alternator via
the master switch, turn on the E-Bus alternator feed switch....
Since the Main Bus will be de-energized due to a failed alternator, I assume
that the EFIS will utilize it's internal battery to keep the EFIS
energized..... OR
is my thought process all wrong !!!
Do I need a seperate switch on my panel to turn the EFIS off, eventhough the
Main Bus is de-energized....
What would the wiring architect be in this case ??
Thanks
Hank
________________________________________________________________________________
| From: | "Ron Shannon" <rshannon(at)CRUZCOM.COM> |
| Subject: | Re: EFIS Battery Back-up Power |
Hank,
If you have just one EFIS, it (or if you have two, the first one) should be
wired to the e-bus -- assuming you want to have the EFIS available during
endurance (battery only) flight ops -- as most of us would like to have.
If you have two EFIS's, you may want to shut one down during endurance ops,
and the second one would therefore be wired to the main bus. (If that second
EFIS already has an automatic internal battery, you may have to shut it down
manually even though it's on the main bus, to save that internal battery.)
This is the way my dual AFS-3400 EFIS system is wired.
The e-bus is normally fed from the main bus through a one-way diode. When
the alternator(s) fail, the e-bus alternate feed is turned ON which powers
the e-bus direct from the battery, i.e., not through the main battery
contactor. (For brief moment, the e-bus is then effectively fed from two
places: the battery upstream of the battery contactor, and the main bus,
from downstream of the battery contactor.) After the e-bus alternate feed
has been turned ON, you immediately turn the main battery contactor OFF, to
rapidly and positively shed those non-essential main bus loads. That's the
sequence (e-bus alt feed ON, then main battery contactor OFF) to keep the
e-bus powered and avoid rebooting things like your EFIS that are on the
e-bus when you shut down the main.
When the e-bus alternate feed is ON, and the main battery contactor and main
bus are OFF, the e-bus will not back feed the main bus because the diode
keeps current from flowing from the e-bus to the main bus.
I hope that helps explain the desired function and results.
Ron
On Sun, May 11, 2008 at 12:58 PM, Henry Trzeciakowski
wrote:
> hammer408(at)comcast.net>
>
> Bob:
>
> I'm planning to install a AFS 3400 with it's own internal battery
> back-up...... fused it to my Main Bus..
>
> How I visualize: main alternator goes off line, I kill the alternator via
> the master switch, turn on the E-Bus alternator feed switch....
> Since the Main Bus will be de-energized due to a failed alternator, I
> assume
> that the EFIS will utilize it's internal battery to keep the EFIS
> energized..... OR
> is my thought process all wrong !!!
>
> Do I need a seperate switch on my panel to turn the EFIS off, eventhough
> the
> Main Bus is de-energized....
>
> What would the wiring architect be in this case ??
>
> Thanks
>
> Hank
>
________________________________________________________________________________
| From: | "John W Livingston" <livingjw(at)earthlink.net> |
| Subject: | Re: EFIS Battery Back-up Power |
Why wouldn't you want to feed it directly from a battery bus with its own
switch? One wire, one switch, done. If you have two, EFISs then two wires,
two switches, done.
----- Original Message -----
From: "Henry Trzeciakowski" <hammer408(at)comcast.net>
Sent: Sunday, May 11, 2008 3:58 PM
Subject: AeroElectric-List: Re: EFIS Battery Back-up Power
>
>
> Bob:
>
> I'm planning to install a AFS 3400 with it's own internal battery
> back-up...... fused it to my Main Bus..
>
> How I visualize: main alternator goes off line, I kill the alternator via
> the master switch, turn on the E-Bus alternator feed switch....
> Since the Main Bus will be de-energized due to a failed alternator, I
> assume
> that the EFIS will utilize it's internal battery to keep the EFIS
> energized..... OR
> is my thought process all wrong !!!
>
> Do I need a seperate switch on my panel to turn the EFIS off, eventhough
> the
> Main Bus is de-energized....
>
> What would the wiring architect be in this case ??
>
> Thanks
>
> Hank
>
>
>
________________________________________________________________________________
| From: | John Morgensen <john(at)morgensen.com> |
| Subject: | Re: EFIS Battery Back-up Power |
Hi Henry,
Henry Trzeciakowski wrote:
>
> Bob:
>
> I'm planning to install a AFS 3400 with it's own internal battery
> back-up...... fused it to my Main Bus..
>
> How I visualize: main alternator goes off line, I kill the alternator via
> the master switch, turn on the E-Bus alternator feed switch....
>
I am at the same stage in my 9A project and I think it is important to
be clear about the E-Bus terminology. You do not say what Z architecture
you are planning. I plan on a Z-13/8 strategy that has an SD-8 backup
alternator. I do NOT plan on an "endurance bus" like a traditional Z-11
architecture. In your scenario, killing the main alternator and
energizing the backup alternator will restore 8 amps of power to the
main bus. I expect the AFS 3500 and the Garmin GPS to stay up on their
internal batteries, if necessary, or the ships' battery while I switch
over. I will shed other loads with individual switches as necessary.
My only experience like this was a rented spam-can with my yoke mounted
Garmin. The first indication of an alternator failure came when the
Garmin complained, "external power lost". I have no idea how long the
alternator had been off line. Since then, I have discovered that the
Garmin 496 has all kinds of configurable alerts including a "low
voltage" that lets you set the threshold.
John
> Since the Main Bus will be de-energized due to a failed alternator, I assume
> that the EFIS will utilize it's internal battery to keep the EFIS
> energized..... OR
> is my thought process all wrong !!!
>
> Do I need a seperate switch on my panel to turn the EFIS off, eventhough the
> Main Bus is de-energized....
>
> What would the wiring architect be in this case ??
>
> Thanks
>
> Hank
>
>
>
________________________________________________________________________________
| From: | "Scott R. Shook" <sshook(at)cox.net> |
| Subject: | Re: Z-19 Item Clarification |
The "requirement" I spoke of came about from an off-field incident in March
which Eggenfellner said that they will not support bridge rectifiers being
used for their engines.
Scott R. Shook
RV-7A (Building)
N696JS (Reserved)
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Mark
Sletten
Sent: Saturday, 10 May, 2008 19:58
Subject: AeroElectric-List: Re: Z-19 Item Clarification
sshook(at)cox.net wrote:
> I hear what you are saying with the 4P3T switch. I just don't see any
other alternatives to switching bus power while still staying within the
recommendations/requirements of Eggenfellner.
I've read the Eggenfellner install manual. There IS a schematic depicting
what the manual refers to as "one way to wire your system" using the switch
to which you refer. I couldn't find anything stating the switch as a
"requirement." As far as I can see, the ONLY benefit this switch provides is
the ability to switch between power supplies with a single switch.
Other than the drawing in the manual, which specific recommendation(s) from
Eggenfellner require you to incorporate a single point of failure in your
electrical system? Maybe a better question might be how has Eggenfellner
justified the recommendation(s) you feel compelled to follow?
sshook(at)cox.net wrote:
> Eventually, all roads in our redundant electrical systems lead to a single
point of failure - the power wire for the component we are powering. That
will always be a single point of failure as I do not know of many components
that have independent, redundant power sources.
Comparing a single, unbroken wire connected at either end with a switch
incorporating 12 external connecting points and a multitude of moving parts
manipulating several internal contacts is a bit of a stretch...
Even if you are convinced of the invincibility of the switch, what design
philosophy drives connecting both fuel pumps to a single pole of the switch?
Regards,
--------
Mark Sletten
Legacy FG N828LM
http://www.legacyfgbuilder.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182437#182437
________________________________________________________________________________
I have a new 0.5 farad capacitor sitting around.? It was left over from a step
sons car audio adventure.? I was thinking about using it for the capacitor in
my Rotax powered project. Since it will likely discharge after some shutdowns,?
This device would likely look like a short circuit, transiently?for every start
up.???is this a reasonable expectation??? Would this be too stressful for
the battery???I would guess the battery would try to charge it long before the
starter starts to crank. ?
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net> |
| Subject: | Re: Rotax capacitor |
>I have a new 0.5 farad capacitor sitting around. It was left over from a
>step sons car audio adventure. I was thinking about using it for the
>capacitor in my Rotax powered project. Since it will likely discharge
>after some shutdowns, This device would likely look like a short circuit,
>transiently for every start up. is this a reasonable
>expectation? Would this be too stressful for the battery? I would guess
>the battery would try to charge it long before the starter starts to crank.
These things are 'tempting' . . . they offer a potential
for a very "quiet" system. However, your misgivings are
well founded. Capacitors this large present some system
dynamics at periods MUCH longer than those presented by
classic noise sources. Getting these puppies charged up
is not a trivial concern. Further, they boost the potential
for short but exceedingly large fault currents in case of
a short.
The battery and/or alternator are not at risk for damage.
I recommend that you stick with the smaller devices which
certainly perform to expectations and offer no special
risks.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
________________________________________________________________________________
| Subject: | Re: Z-19 Item Clarification |
| From: | "ZuluZephyr" <zuluzephyr(at)yahoo.com> |
Scott,
The failure that you mention was due to an incorrectly sized rectifier or diode
that was not designed to carry the load that was applied. Not because the basic
design is faulty. All designs have advantages and disadvantages.
Eggenfellner's design solves certain potential problems and creates others.
Ultimately, it is your plane and your risks. The trick is to make fully informed
decisions about the trade-offs in design and decide what your risk tolerance
is for the various design options.
Rocky Morrison
Sportsman / H6
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182633#182633
________________________________________________________________________________
| Subject: | Re: Z-19 Item Clarification |
| From: | "Mark Sletten" <marknlisa(at)hometel.com> |
sshook(at)cox.net wrote:
> The "requirement" I spoke of came about from an off-field incident in March which
Eggenfellner said that they will not support bridge rectifiers being used
for their engines.
Scott,
1. The NTSB has not completed its investigation of this accident yet. I would hesitate
to base design decisions on speculation regarding ANY accident -- especially
if the speculation comes from a party with an interest in the results of
that investigation.
2. I do not believe the accident aircraft to which you refer incorporated a bridge
rectifier in the power path to the critical engine components.
3. If you are leery about using bridge rectifiers there are other products capable
of controlling power routing besides them.
Regards,
--------
Mark Sletten
Legacy FG N828LM
http://www.legacyfgbuilder.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182673#182673
________________________________________________________________________________
| From: | "Carlos Trigo" <trigo(at)mail.telepac.pt> |
| Subject: | GPS antennas with miniature connector |
Listers
I have 2 GPS antennas to install, one is for my Trutrak ADI and the other
for the GRT - EFIS, both having internal GPS.
I attached 2 pictures of one of them, they are similar, both use a thin
cable (less than 1/8" outer diameter) and a miniature brass connector.
Since we must always seek to save some weight in our birds, I have 2
questions:
First question, which is probably dumb, but here it goes: can I install only
one antenna and T the cable for both devices?
Second question: if I want to get rid of that much cable length, can I cut
it somewhere in the middle, remove the unnecessary length, and reconnect the
cable ends? If yes, how do I do it?
Or is it better to forget the existing connector, cut the necessary length
and use a new connector? In this case, where can I find these miniature
connectors and is there a special crimper for these?
Carlos Trigo
________________________________________________________________________________
| Subject: | Re: Z-19 Item Clarification |
I spoke with two Legacy builders from Princeton, NJ on Saturday. One of
their fellow builders was flying their RV-9 and Egg Sube when a $20.00
switch or diode failed. You can have all the batteries and busses you
like, the Sube ignition maintains a single point of failure. That's why
they call it Experimental.
The crash pilot escaped with a mangled foot and broken leg. He is
re-building and now a favorite customer at Lycoming. BTW - If he had
turned right off after take-off there are smoother fields available for
landing. As Murphy would have it, he went left towards the trees.
Performance goes far beyond switches. Nothing is perfect, but Lycoming
still offers the Briggs and Stratton reliability to bring you home again
and again.
Keep it smart; wire for reliability not convenience.
The result:
http://www.ntsb.gov/ntsb/brief.asp?ev_id 080319X00337&key=1
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Mark
Sletten
Sent: Monday, May 12, 2008 10:00 AM
Subject: AeroElectric-List: Re: Z-19 Item Clarification
-->
sshook(at)cox.net wrote:
> The "requirement" I spoke of came about from an off-field incident in
> March which Eggenfellner said that they will not support bridge
> rectifiers being used for their engines.
Scott,
1. The NTSB has not completed its investigation of this accident yet. I
would hesitate to base design decisions on speculation regarding ANY
accident -- especially if the speculation comes from a party with an
interest in the results of that investigation. 2. I do not believe the
accident aircraft to which you refer incorporated a bridge rectifier in
the power path to the critical engine components. 3. If you are leery
about using bridge rectifiers there are other products capable of
controlling power routing besides them.
Regards,
--------
Mark Sletten
Legacy FG N828LM
http://www.legacyfgbuilder.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=182673#182673
________________________________________________________________________________
| From: | Ernest Christley <echristley(at)nc.rr.com> |
| Subject: | Re: GPS antennas with miniature connector |
Carlos Trigo wrote:
> Listers
>
> I have 2 GPS antennas to install, one is for my Trutrak ADI and the other
> for the GRT - EFIS, both having internal GPS.
> I attached 2 pictures of one of them, they are similar, both use a thin
> cable (less than 1/8" outer diameter) and a miniature brass connector.
>
> Since we must always seek to save some weight in our birds, I have 2
> questions:
>
> First question, which is probably dumb, but here it goes: can I install only
> one antenna and T the cable for both devices?
>
Yes. You'll just have to fly much closer to the satellites in order to
get sufficient signal strength to get a lock. Remember that those
satellites are REALLY far away (22,500 miles ?), which means your
receiver has to capture a very weak signal. Cutting the received signal
in half isn't going to be helpful.
> Second question: if I want to get rid of that much cable length, can I cut
> it somewhere in the middle, remove the unnecessary length, and reconnect the
> cable ends? If yes, how do I do it?
> Or is it better to forget the existing connector, cut the necessary length
> and use a new connector? In this case, where can I find these miniature
> connectors and is there a special crimper for these?
>
That can be done, but you're trading a crimp done constantly by a
machine that has some semblance of quality control for a one-off job
done by someone that (so far) doesn't even know which crimper to use.
You could eventually do a better job than the machine. The question is
if the weight savings are worth the expense and effort.
I suggest you weigh that 1/8" cable and then decide if it is worth your
effort. I you think it is, then try splitting it then see how many
satellites it the receiver will lock onto. The ones to watch for are
the ones on the horizons, as they will be giving the weakest signals.
________________________________________________________________________________
| Subject: | Re: RE: Re: Z-19 Item Clarification |
| From: | "Glaeser, Dennis A" <dennis.glaeser(at)eds.com> |
----------------------------------------------------------------
The "requirement" I spoke of came about from an off-field incident in
March which Eggenfellner said that they will not support bridge
rectifiers being used for their engines.
Scott R. Shook RV-7A (Building) N696JS (Reserved)
----------------------------------------------------------------
The cause of that incident has not been determined. Jan's assessment
that it was 'the diodes' is his pure unfounded speculation, and totally
wrong IMHO and experience. They were high capacity (45V 60A) diodes -
NOT a bridge rectifier (which I agree would be inadequate for this
application).
I am using diodes (50HQ035) in my Egg H6 ignition circuit without any
problems (all 14.5 hours so far :-) My electrical design (similar to
Z-19) can be viewed at:
http://www.wideopenwest.com/~glaesers/electrical_plan.htm
I have a temp sensor on the highest amp (EFI) diode on the main ignition
circuit and the highest temp it has seen is 103F (it's rated to 350F).
My design was complete, and my airplane wired well before the current H6
installation manual was published. When Jan decided to get away from
using the EXPBUS, he was looking for alternative designs, so I sent him
mine, but obviously it wasn't adopted.
Jan does not support using diodes, and that's OK with me. There is
nothing 'wrong' with their design, and the 4PDT switch they specify is a
high quality switch. I just prefer multiple redundant (and much cheaper)
switches. My design could be implemented without the diodes and would
work just fine, but would not be as 'operator error proof' under certain
(albeit highly unlikely) failure modes.
Dennis Glaeser
RV-7A Egg-H6 - flying - Phase 1
________________________________________________________________________________
| From: | "Carlos Trigo" <trigo(at)mail.telepac.pt> |
| Subject: | GPS antennas with miniature connector |
Dear Ernest
Although you were not of much help, thanks anyway.
If I didn't think it was worth the effort to save the weight, I wouldn't
have asked.
Can somebody else please indicate me a way of getting rid of those 2 useless
coils of GPS antenna cable?
Carlos
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-
> server(at)matronics.com] On Behalf Of Ernest Christley
> Sent: segunda-feira, 12 de Maio de 2008 16:33
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: GPS antennas with miniature connector
>
>
> Carlos Trigo wrote:
> > Listers
> >
> > I have 2 GPS antennas to install, one is for my Trutrak ADI and the
other
> > for the GRT - EFIS, both having internal GPS.
> > I attached 2 pictures of one of them, they are similar, both use a thin
> > cable (less than 1/8" outer diameter) and a miniature brass connector.
> >
> > Since we must always seek to save some weight in our birds, I have 2
> > questions:
> >
> > First question, which is probably dumb, but here it goes: can I install
only
> > one antenna and T the cable for both devices?
> >
> Yes. You'll just have to fly much closer to the satellites in order to
> get sufficient signal strength to get a lock. Remember that those
> satellites are REALLY far away (22,500 miles ?), which means your
> receiver has to capture a very weak signal. Cutting the received signal
> in half isn't going to be helpful.
> > Second question: if I want to get rid of that much cable length, can I
cut
> > it somewhere in the middle, remove the unnecessary length, and reconnect
the
> > cable ends? If yes, how do I do it?
> > Or is it better to forget the existing connector, cut the necessary
length
> > and use a new connector? In this case, where can I find these miniature
> > connectors and is there a special crimper for these?
> >
> That can be done, but you're trading a crimp done constantly by a
> machine that has some semblance of quality control for a one-off job
> done by someone that (so far) doesn't even know which crimper to use.
> You could eventually do a better job than the machine. The question is
> if the weight savings are worth the expense and effort.
>
> I suggest you weigh that 1/8" cable and then decide if it is worth your
> effort. I you think it is, then try splitting it then see how many
> satellites it the receiver will lock onto. The ones to watch for are
> the ones on the horizons, as they will be giving the weakest signals.
>
________________________________________________________________________________
| Subject: | Re: GPS antennas with miniature connector |
| From: | simon(at)synchronousdesign.com |
> First question, which is probably dumb, but here it goes: can I
> install only one antenna and T the cable for both devices?
Carlos, GPS satellites transmit very weak signals, and most GPS receivers
are designed to get as much signal strength as possible for best
reliability. Putting a T between the antennas and the receiver will
guarantee failure or at best, lousy performance. By the way, GPS
satellites are not 22,500 miles out. That radius would put them in
synchronous orbit with the TV and other satellites. Instead, they are
12,500 miles out and orbit north to south. The transmitters' output
powers guarantee weak signals by the time they make it into our
atmosphere. The best solution is to provide a dedicated GPS amtenna for
each receiver.
> Second question: if I want to get rid of that much cable length,
> can I cut it somewhere in the middle, remove the unnecessary
> length, and reconnect the cable ends? If yes, how do I do it?
> Or is it better to forget the existing connector, cut the
> necessary length and use a new connector? In this case, where
> can I find these miniature connectors and is there a special
> crimper for these?
Again, any tampering with the cable between the antenna and the receiver
will introduce attenuation. There is a good solution here, though.
Instead of cutting it in the middle, just cut it to length and then place
the same type connector on the cut end. You may have to buy special
tooling to do this, but if you really want to do it and you do it right,
you will not suffer signal degradation. All connectors introduce some
degradation, but all you're doing is moving the degradation from N feet
out to N/2 feet out.
Simon Ramirez
Oviedo, FL USA
________________________________________________________________________________
| Subject: | Re: GPS antennas with miniature connector |
| From: | "Matt Prather" <mprather(at)spro.net> |
Aren't many GPS antennas active (amplified, powered)? If so, it should be
possible to design an impedance match circuit from the output of the
antenna to the input of the two receivers. It's also possible that the
output of the amplified antenna is robust enough to not require any match
circuitry for adequate performance...
Regards,
Matt-
>
>> First question, which is probably dumb, but here it goes: can I
>> install only one antenna and T the cable for both devices?
>
> Carlos, GPS satellites transmit very weak signals, and most GPS receivers
> are designed to get as much signal strength as possible for best
> reliability. Putting a T between the antennas and the receiver will
> guarantee failure or at best, lousy performance. By the way, GPS
> satellites are not 22,500 miles out. That radius would put them in
> synchronous orbit with the TV and other satellites. Instead, they are
> 12,500 miles out and orbit north to south. The transmitters' output
> powers guarantee weak signals by the time they make it into our
> atmosphere. The best solution is to provide a dedicated GPS amtenna for
> each receiver.
>
>> Second question: if I want to get rid of that much cable length,
>> can I cut it somewhere in the middle, remove the unnecessary
>> length, and reconnect the cable ends? If yes, how do I do it?
>> Or is it better to forget the existing connector, cut the
>> necessary length and use a new connector? In this case, where
>> can I find these miniature connectors and is there a special
>> crimper for these?
>
> Again, any tampering with the cable between the antenna and the receiver
> will introduce attenuation. There is a good solution here, though.
> Instead of cutting it in the middle, just cut it to length and then place
> the same type connector on the cut end. You may have to buy special
> tooling to do this, but if you really want to do it and you do it right,
> you will not suffer signal degradation. All connectors introduce some
> degradation, but all you're doing is moving the degradation from N feet
> out to N/2 feet out.
>
> Simon Ramirez
> Oviedo, FL USA
>
>
April 22, 2008 - May 12, 2008
AeroElectric-Archive.digest.vol-hu