Today's Message Index:
----------------------
1. 07:27 AM - Re: Contactors (Vince Ackerman)
2. 08:23 AM - Re: Substitute for Shoo Goo (Gilles.Thesee)
3. 08:53 AM - Contactor Question (Charles Brame)
4. 09:54 AM - Garmin GMA340 music volume was: Updated instructions for Audio Iso Amp (royt.or@netzero.com)
5. 10:50 AM - Re: Substitute for Shoo Goo (Robert L. Nuckolls, III)
6. 10:51 AM - Re: Contactors (Robert L. Nuckolls, III)
7. 11:52 AM - Re: Updated instructions for Audio Iso Amp (Dan Checkoway)
8. 01:06 PM - Re: Wire Selection (Joseph Kearns, DO,MPH,FACOEM)
9. 01:22 PM - Re: Contactor Question (Robert L. Nuckolls, III)
10. 01:45 PM - Re: Alternator Noise in Headset - Epilogue? (Robert L. Nuckolls, III)
11. 02:07 PM - An electrical system for my homebuilt (Robert L. Nuckolls, III)
12. 02:11 PM - Re: Contactors (Steve Sampson)
13. 03:04 PM - Re: Watsonville Seminar Nov 8/9 (David.Shani@sanmina-sci.com)
14. 03:30 PM - Re: Dimmers (Robinson, Chad)
15. 03:44 PM - Fuses - 28v (dschaefer1@kc.rr.com)
16. 05:08 PM - Re: Contactors (Phil Birkelbach)
17. 05:17 PM - Re: Watsonville Seminar Nov 8/9 (Robert L. Nuckolls, III)
18. 05:42 PM - Re: Contactors (Robert L. Nuckolls, III)
19. 05:43 PM - Re: Fuses - 28v (Robert L. Nuckolls, III)
20. 06:18 PM - Re: Fuses - 28v (David Swartzendruber)
21. 06:56 PM - Nav/Loc/GS and Comm antennae internally mounted (Treff, Arthur)
22. 08:27 PM - Re: Contactors (Robinson, Chad)
Message 1
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--> AeroElectric-List message posted by: Vince Ackerman <vack@mac.com>
Bob,
Do you know the lowest voltage required to hold the coil closed (on B&C
Contactor)? I don't have a variable power supply or I'd check it myself.
Thanks
Vince
Message 2
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| Subject: | Re: Substitute for Shoo Goo |
--> AeroElectric-List message posted by: "Gilles.Thesee" <Gilles.Thesee@ac-grenoble.fr>
Bob,
Thanks for your answer and your offer.
Before you get into too much trouble I'll try and make sure we really don't
have a suitable substitute at hand.
Had a peek at their website. Rally amazing stuff indeed. I gather it is a
rubber base sealant-adhesive or something.
Thank you,
Gilles
> No, hot melts are a whole other attachment technology. The
> more generic, industrial equivalent of Shoe Goo is E-6000
> offered by Eclectic Products (also makes Shoe Goo). Check with
> hardware and craft stores. If push comes to shove, I could
> get some and send it to you. This is a unique product with
> extra-ordinary capabilities. There are undoubtedly other products
> with similar capabilities but I've not researched any.
>
>
> Bob . . .
>
>
Message 3
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| Subject: | Contactor Question |
--> AeroElectric-List message posted by: Charles Brame <charleyb@earthlink.net>
I have a Van's three terminal Master Contactor. I have two fat wires and
a diode attached to the BAT terminal. I need to connect a back up
alternator lead to the same terminal, but there ain't no more room. Is
there an easy solution other than going to a four terminal contactor?
Charlie Brame
RV-6A N11CB
San Antonio
Message 4
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| Subject: | Garmin GMA340 music volume was: Updated instructions |
for Audio Iso Amp
--> AeroElectric-List message posted by: royt.or@netzero.com
Jim, Bob,
I'm using the equivalent of a boostaroo (see http://www.boostaroo.com/) that I got from Radio Shack for about $20.00. This is ~$30.00 on the boostaroo web page. (Currently, I can not find this on the Radio Shack web page.)
This works well for using a portable CD/MP3 player with the Garmin GMA340 in my
plane. I plan to try the Garmin update in the future.
Regards,
Roy
CH601HDS, Rotax 912S, All electric panel. 130 hours since first flight on 5/12/03
Message 5
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| Subject: | Re: Substitute for Shoo Goo |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 05:23 PM 10/23/2003 +0200, you wrote:
>--> AeroElectric-List message posted by: "Gilles.Thesee"
><Gilles.Thesee@ac-grenoble.fr>
>
>Bob,
>
>Thanks for your answer and your offer.
>Before you get into too much trouble I'll try and make sure we really don't
>have a suitable substitute at hand.
>Had a peek at their website. Rally amazing stuff indeed. I gather it is a
>rubber base sealant-adhesive or something.
I think it's a polyurethane or close cousin. It's tough as
a boot when cured (hence characteristics adequate for gluing
one's sneakers back together). Really more of a plastic than
a rubber. It would be no big deal to ship you a tube if
needs be. I can get it in a hobby shop two blocks from
my house.
I note that Eclectic's website speaks of retail outlets
in US, Canada, Mexico and Asia . . . hmmm . . . might
have to send you some. I'll check with Todd at B&C
to see if they're interested in stocking it.
Bob . . .
Message 6
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 07:26 AM 10/23/2003 -0700, you wrote:
>--> AeroElectric-List message posted by: Vince Ackerman <vack@mac.com>
>
>Bob,
>
>Do you know the lowest voltage required to hold the coil closed (on B&C
>Contactor)? I don't have a variable power supply or I'd check it myself.
>
>Thanks
>
>Vince
At room temperature, the one I have picks up at 6 and drops
out at 4 volts.
Bob . . .
Message 7
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| Subject: | Re: Updated instructions for Audio Iso Amp |
--> AeroElectric-List message posted by: "Dan Checkoway" <dan@rvproject.com>
Jim,
I can tell you that the optional gain does work very well on the GMA-340.
It boosts it more than you might think. I went and installed a little
toggle switch on my panel to control the boost on/off. You might want to
give it a shot and try it out before going with a more complicated solution.
Just my 2 cents!
)_( Dan
RV-7 N714D
http://www.rvproject.com
----- Original Message -----
From: "J. Oberst" <joberst@cox-internet.com>
Subject: Re: AeroElectric-List: Updated instructions for Audio Iso Amp
> --> AeroElectric-List message posted by: "J. Oberst"
<joberst@cox-internet.com>
>
> Bob, I have a Garmin GMA340 audio panel, and I have installed some mini
> earphone jacks that go to its music input. Problem is with portable tape
or
> CD players, their output level is far short of what's needed to hear them
in
> the headphones. Garmin has a fix that provides 10dB gain, but that
doesn't
> seem to me like it will be enough, so I don't want to start removing
surface
> mount resistors to do it. What would be simplest would be to add a stereo
> audio amplifier between my panel jacks and the Garmin music input.
>
> I saw this post on an audio isolation amplifier, and was wondering if this
> is what I need. Or if not, has there been a design (or a simple box I can
> buy) discussed before?
>
> Thanks.
>
> Jim Oberst
>
> ----- Original Message -----
> From: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
> To: <aeroelectric-list@matronics.com>
> Subject: AeroElectric-List: Updated instructions for Audio Iso Amp
>
>
> > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <bob.nuckolls@cox.net>
> >
> > I've combed out some errors and added a note (14) to
> > point out connector pin variations depending on how
> > the connector is mounted. Download:
> >
> > http://www.aeroelectric.com/Catalog/AEC/9009/9009-700D.pdf
> >
> > Bob . . .
> >
> > --------------------------------------------
> > ( Knowing about a thing is different than )
> > ( understanding it. One can know a lot )
> > ( and still understand nothing. )
> > ( C.F. Kettering )
> > --------------------------------------------
> >
> >
>
>
Message 8
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| Subject: | Re: Wire Selection |
--> AeroElectric-List message posted by: "Joseph Kearns, DO,MPH,FACOEM" <Kearns@pol.net>
Valued contributors.
Does anyone have an excel spreadsheet that will consider temp, length,
current, bundled, ... and will give the suggested gage according to the
AC43-13? Thanks.
Message 9
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| Subject: | Re: Contactor Question |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 10:53 AM 10/23/2003 -0500, you wrote:
>--> AeroElectric-List message posted by: Charles Brame
><charleyb@earthlink.net>
>
>I have a Van's three terminal Master Contactor. I have two fat wires and
>a diode attached to the BAT terminal. I need to connect a back up
>alternator lead to the same terminal, but there ain't no more room. Is
>there an easy solution other than going to a four terminal contactor?
Hmmm . . . the Cole-Hersee contactors have a fat wire stud
length about 0.1" shorter than the RBM/Stancore parts from
B&C . . . it can present a problem with terminal stacking.
Do you have a battery bus? If so, you can tie the aux alternator
to a fuse slot on the battery bus and eliminate the fusible link.
I'd go for a 15A fuse in off the battery bus.
Bob . . .
Message 10
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| Subject: | Re: Alternator Noise in Headset - Epilogue? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 09:30 PM 10/22/2003 -0700, you wrote:
>--> AeroElectric-List message posted by: Pete Waters <pedroagua@yahoo.com>
>
>Bob,
>
> If the weather cooperates, I'll even bring the RV-4 we've been
> discussing on the Aerolelectric list.
great!
> BTW, I replaced the voltage regulator I had with an automotive one (a
> Transpo), and I no longer hear the Morse Code-like noise. The new VR
> cost me about $20. I also took the alternator and old regulator out of
> the airplane to an automotive alternator shop. They found nothing wrong
> with either, but at least in the process I learned that the alternator,
> which is still in great shape, is a 35 A Nippondenso model off a mid-70's
> Honda. The old voltage regulator is probably of the same vintage, but is
> completely unmarked and therefore a complete mystery part.
Good detective work. I've run into a whistling regulator
a couple of times that I can recall. My design for the B&C LR-1 and
LR-2 regulators would go into oscillation at an inaudible
radio frequency that upset ADF and Loran receivers when driving
a long regulator-to-field wire in canard pushers. I think
I recall talking with two different builders about adding
a capacitor inside the regulator to stop the problem. We
got it right with the LR-3 series regulators later.
> For $20 it was worth it for me to just replace the VR so that I could
> write a model and part number on the massive airplane configuration
> spreadsheet I'm gradually constructing.
Sure. The generic "ford" regulators are a good example
of a $5 to $20 regulator that gives good service.
> I also replace the automotive voltmeter that came in the airplane with
> an Electronics Instruments VA-1A volt/ammeter so I could have an ammeter
> in the plane to diagnose any future electrical issues. Right off, I
> learned that, with both landing
> lights off, I pull about 13 A with everything else on; with both
> landing lights on, I pull 31 A (off a 35A alternator) and get a
> flickering discharge light on the ammeter.
Hmmm . . . fat rascals aren't they?
> So, I clearly need to either (a) go to lower-wattage landing lights, or
> (b) disconnect one of them,
or put them on separate switches so you have one or both but
always an independent spare should one turn belly up.
> (c) live with it for the short period on final when everything is one,
this isn't a sin either . . . how about two switches with a wigwag
system. You can turn on both lights in the last few seconds before
flare and keep total lighting loads down to 9A before this time.
> or (d) get a higher-output alternator.
I think what you have will do just fine.
> I'll probably go for (a) in the short term and (d) at the next annual.
> I'm not sure if the headset noise won't return, but at least I'm
> learning how this plane is wired.
> I'll copy this to the Aeroelectric list also to share it with the bubbas.
I appreciate that. See you in Watsonville!
Bob . . .
Message 11
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| Subject: | An electrical system for my homebuilt |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 11:07 PM 10/19/2003 +0200, you wrote:
>Bob,
>
>
>In France, a small minority of people have the "Legion d'honneur". A
>minority in this minority really deserves it. I believe that if you live
>in France you would deserve it!
>I build a two-seats aircraft in composite (carbon epoxy). It is a MCR 01
>SPORTSTER known in US under the name of LAFAYETTE. It is powered with a
>ROTAX 912 and gently cruise at 140 Kts.
>
>I discovered your Web site thanks to (excellent!) friend of mine. I do not
>put myself any more a question, I have the answers!!!!! It is a true gold
>mine and I think that it is necessary to be right and don't forget the minor!!
>
>I want to buy at B&C all which I need to carry out my wiring and first of
>all, THE BOOK !!.
Thank you for the kind words . . .
>As the Atlantic Ocean separates us, I have many questions to ask to you in
>order to avoid making errors by writing this order.
> * Which is the wire is necessary to employ for the control circuits?
> The electric considerations would allow very fine gauges: AWG 34 for the
> relays of engine control of flaps (200 ma) by ex. But of the mechanical
> considerations (brittleness) and especially the possibility of crimping
> seems to limit the choice to AWG 22. Is it correct?
Correct. We use some 24AWG wire in harnesses on Premier at Raytheon
with a mixed bag of reaction from folks on the line. Personally,
22AWG is the smallest wire I would use in the airframe. Some folks
have wired with 20AWG as the smallest . . . it fits into all but a few
avionics connectors and handles currents up to 7A which covers the
majority of installed systems. 20AWG Tefzel is no heavier than 22AWG
nylon over PVC of yesteryear . . . and in any case . . . would probably
add less than a pound of empty weight to a simple airplane.
> * Is your S704-1 relay a good choice for the engine control of flaps
> (10 A) and trim (5 A). I will use 2 relays in "H bridge" for each one.
It's certainly BIG enough and one could consider smaller relays. I like
this particular product for ease of use. It's easy to mount and wire.
> * Do you think that it is possible (and desirable) to entirely carry
> out a full disconnectable instrument panel thanks to D-Sub connectors.
If you use any connector for this purpose, a D-sub is hard to beat.
Consider also building your airframe to panel wire harness with
perhaps 1' of slack in it so that you can dismount the panel and
lay it aside without disconnecting it. Either way should serve
you well as long as the connector quality is good. Machined pin
d-subs would be my connector of choice.
> * When you are read, one could believe that the "buses bar" are
> reserved for the "breakers". I will use fuses (of course !) and in
> particular Fuseholder (20 position). Which is the good method to
> distribute the PLUS to all fuses?
A bus bar is built into the fuse holder. A single fat screw visable
centered on one end is the commom (+) supply for all of the fuses
in the holder.
> * Logically, it would be necessary to protect the wiring located
> between the battery and the Fuseholder with a principal fuse located
> close to the battery. Does one have to do it?
You don't need to do this. These wires are classically BIG. Further,
there are only a few and easy to install with extra care to preclude
mechanical damage that might ground the wire. When you get the book,
you will note there are no special provisions for protecting fat
wires in the airplane. All fat-wires in certified single engine
airplanes are treated the same way here in the US
> * I do not see on B&C Web site the in line fuse (JJN/JJS Serie
> cartridge fuse) allowing to protect the alternator which you describe in
> your article "Circuit_protection.pdf".
The JJN/JJS series fuses are offered only for spares for folks who
installed them per recommendations of some years back. B&C uses the
ANL series devices in their kits for certified alternators so it
made more sense to convert to the ANL series for all high current
circuit protection.
> * In France, the MICROAIR VHF has been approved only for one month
> (!). It interests me much, because beyond his good service/price ratio,
> it is the least long of the market and in my case, they is very
> advantageous. Do you have good opinions on this radio?
I have sold about two dozen. Out of these, I am aware
of only one that needed to be returned for service. This
is a relatively new product and I expect some early
learning glitches . . . I think their radios are good
value and so far, their willingness to fix misbehaving
radios is quite good. I would probably put Microair radios
in the panel if I were building an airplane.
> * I saw that you provide a harness for this radio. Which are its
> advantages compared to that which provided MICROAIR? It is not on the B
I don't know the details of their harness but I suspect it's
not much different than the one we offered. I'm out of stock
on those harnesses for now put plan to do a batch of both 760VHF
and T2000 harnesses and put them back up on my website. B&C
doesn't plan to offer them but I'll have them again soon.
> * Which is the best place to install a "spike catching diode", at the
> boundaries of the contact or the boundaries of the coil?
On the coil.
See http://www.aeroelectric.com/articles/spikecatcher.pdf
> * Which is the good protection device for the engine of the starter?
> The question of the protection of the cable between the battery and the
> relay also arises (?).
These wires are very rarely a problem and are not protected.
The wiring diagrams in the book will illustrate placement
and numbers of recommended circuit protection.
>
>Thank you for your answers.
You are most welcome. Good luck on your project.
I will invite you to join us on the AeroElectric List
to continue this and similar discussions. It's useful to
share the information with as many folks as possible.
A further benefit can be realized with membership on
the list. There are lots of technically capable folks
on the list who can offer suggestions too. You can
join at . . .
http://www.matronics.com/subscribe/
Well considered and technically elegant answers to
all of your questions are waiting for you there. Also,
check out the downloadable materials at
http://www.aeroelectric.com
Thanks!
Bob . . .
|---------------------------------------------------|
| A lie can travel half way around the world while |
| the truth is till putting on its shoes . . . |
| -Mark Twain- |
|---------------------------------------------------|
Message 12
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--> AeroElectric-List message posted by: "Steve Sampson" <SSampson.SLN21@london.edu>
Bob - thanks for that. In that case I will get a S701-1.
But for my education, why cant I use the VANS 3 terminal unit? Surely it is
internally wired as in the top right of the attached diag. with the coil
between the third terminal and the case which is grounded to the firewall?
Doesnt energising the coil, terminal to case pull the contactor in, and vica
versa? (If the diag. does not go through matronics, it is yours and
labelled - 'OV protection for built in regulator 1.0' It appears to have the
filename 'bleadov.pdf' which I suspect is your name for it.)
Thanks, Steve.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert
L. Nuckolls, III
Subject: Re: AeroElectric-List: Contactors
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
At 08:35 PM 10/21/2003 +0100, you wrote:
>--> AeroElectric-List message posted by: "Steve Sampson"
><SSampson.SLN21@london.edu>
>
>Why do contactors normally have one side labelled to the battery and the
>other to the load? They would appear to be a symmetrical device from the
>internal diagram in Bob's book.
some but not all contactors have one side of coil connected
internally to the BAT terminal. Often, a manufacturer uses
the same shell for all versions of the contactor and one of
the fat terminals gets marked BAT even tho it's really significant
for only part of the product line.
>The reason for the question is that I am wiring up the firewall of an RV9a
>and am using basically diags Z9 and Z24 (to control an internally regulated
>alternator). Placement of the contactor to kill the supply from the
>alternator means the wiring would be simpler if the device was wired
>'backwards'. In fact the current will also flow through it backwards in
that
>if a contactor is normally handling current flowing from a battery to
>devices this contactor will be handling current flowing from an alternator
>to a battery.
If you're using a 4-terminal device, you can ignore any
marking suggesting one of the fat terminals goes to
BAT.
>The specific units concerned are the VANS Master Relay and the VANS ND 60
>amp alternator.
As I recall, Van's master relay is a 3-terminal device with one
coil lead attached to BAT. This contactor can't be used for
alternator disconnect, you need a 4-terminal device like
the S701-1 offered by B&C at:
http://www.bandc.biz/S701-1.html
and others.
Bob . . .
Message 13
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| Subject: | Re: Watsonville Seminar Nov 8/9 |
--> AeroElectric-List message posted by: David.Shani@sanmina-sci.com
Hi Bob,
I am an EAA Chapter 119 member...and I did not hear a thing about your
seminar coming to Watsonville Nov 8th.
Where are you going to conduct the seminar - I know of quit a few people
that will be interested...
Thanks
David Shani
Email: david.shani@sanmina-sci.com
Message
<META content="MSHTML 6.00.2800.1264" name=GENERATOR>
Hi
Bob,
<SPAN
class=820361117-23102003>
I am an
EAAChapter 119 member...and I did not hear a thing about your
seminarcoming to Watsonville Nov 8th.
Where are you going
to conduct the seminar - I know of quit a few people that will be
interested...
<SPAN
class=820361117-23102003>
<SPAN
class=820361117-23102003>Thanks
David Shani
Email:
david.shani@sanmina-sci.com
Message 14
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--> AeroElectric-List message posted by: "Robinson, Chad" <crobinson@rfgonline.com>
John Schroeder wrote:
>
> To get relatively uniform dimming/illumination from a linear
> regulator on a string of LED's you should have them in parallel.
> Correct?
You can run LEDs in series or parallel. There is a short, sweet summary of the
pros and cons of series vs. parallel LEDs at:
http://www.bivar.com/eLetter/driving-la.htm
Technically, by running them in series, you guarantee that they consume the same
amount of current and thus you theoretically get more consistent lighting. (It's
the current through the device that sets the brightness.) Manufacturing tolerances
can alter the voltage drop, so parallel LEDs may not always be exactly
the same brightness.
Eric's point about series strings is sound - you've basically got the same amount
of power through the string that you'd have with only a single diode. So is
John R's - you don't want to run too many, because you need "headroom" both to
make sure they stay lit if the power rail sags, but also because that headroom
is your dimming range.
I'd like to add a few points (heard that before? <grin>):
1. Series LEDs aren't a panacea. When LEDs fail they can fail open OR shorted.
If they fail open you lose the entire chain, like you expect. But if they fail
closed the same can happen - the voltage drop is gone, so the current flow goes
up, and you can get a cascade failure. This really isn't a common occurrence,
but I figured I'd cover all the bases.
2. Dimmers are usually designed so a full turn of the potentiometer dial is a full
range from 0 (or nearly 0) to the power supply rail. You usually can't share
a dimmer controlling series LED chains with a few individual devices in parallel,
or regular light bulbs, because they won't dim at the same rate. (Well,
bulbs would be brighter anyway, so you probably wouldn't want them, but still...)
3. If the LEDs aren't going to be near each other, making a series chain can be
a pain. Since wiring and connectors are one of the most common (Bob, any stats
here?) areas for a failure, I'm personally not all that fond of daisy-chaining
widely separated LEDs. This is best used if they're close together, or you
can get a rats nest of wiring.
By the way, it's simple math, but there's a neat calculator for this formula at:
http://ourworld.compuserve.com/homepages/Bill_Bowden/led.htm
It's more complex than others in that it handles multiple LEDs but if you're planning
on chaining it's a neat tool.
Regards,
Chad
Message 15
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--> AeroElectric-List message posted by: dschaefer1@kc.rr.com
Bob .. this may be a stupid question .. but.. I've got a couple of 28 volt items
in my panel (MFD). I've got a commercial 28 volt 'booster' from KGS Electrics
I'm going to power a 6 fuse '28v bus'. What fuses do I use in this bus? Are
they the same as 12v amperage-wise?
Thanks...
David
Message 16
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--> AeroElectric-List message posted by: "Phil Birkelbach" <phil@petrasoft.net>
The coil on Van's three terminal device isn't between the terminal and
ground it is between the terminal and the BATT terminal. You ground the
little terminal on the contactor to get it to pull in.
I had the same problem and had to order the S701-1 to get it to work.
Godspeed,
Phil
----- Original Message -----
From: Steve Sampson <SSampson.SLN21@london.edu>
Subject: RE: AeroElectric-List: Contactors
> --> AeroElectric-List message posted by: "Steve Sampson"
<SSampson.SLN21@london.edu>
>
> Bob - thanks for that. In that case I will get a S701-1.
>
> But for my education, why cant I use the VANS 3 terminal unit? Surely it
is
> internally wired as in the top right of the attached diag. with the coil
> between the third terminal and the case which is grounded to the firewall?
> Doesnt energising the coil, terminal to case pull the contactor in, and
vica
> versa? (If the diag. does not go through matronics, it is yours and
> labelled - 'OV protection for built in regulator 1.0' It appears to have
the
> filename 'bleadov.pdf' which I suspect is your name for it.)
>
> Thanks, Steve.
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server@matronics.com
> [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert
> L. Nuckolls, III
> To: aeroelectric-list@matronics.com
> Subject: Re: AeroElectric-List: Contactors
>
>
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <bob.nuckolls@cox.net>
>
> At 08:35 PM 10/21/2003 +0100, you wrote:
> >--> AeroElectric-List message posted by: "Steve Sampson"
> ><SSampson.SLN21@london.edu>
> >
> >Why do contactors normally have one side labelled to the battery and the
> >other to the load? They would appear to be a symmetrical device from the
> >internal diagram in Bob's book.
>
> some but not all contactors have one side of coil connected
> internally to the BAT terminal. Often, a manufacturer uses
> the same shell for all versions of the contactor and one of
> the fat terminals gets marked BAT even tho it's really significant
> for only part of the product line.
>
>
> >The reason for the question is that I am wiring up the firewall of an
RV9a
> >and am using basically diags Z9 and Z24 (to control an internally
regulated
> >alternator). Placement of the contactor to kill the supply from the
> >alternator means the wiring would be simpler if the device was wired
> >'backwards'. In fact the current will also flow through it backwards in
> that
> >if a contactor is normally handling current flowing from a battery to
> >devices this contactor will be handling current flowing from an
alternator
> >to a battery.
>
> If you're using a 4-terminal device, you can ignore any
> marking suggesting one of the fat terminals goes to
> BAT.
>
>
> >The specific units concerned are the VANS Master Relay and the VANS ND 60
> >amp alternator.
>
> As I recall, Van's master relay is a 3-terminal device with one
> coil lead attached to BAT. This contactor can't be used for
> alternator disconnect, you need a 4-terminal device like
> the S701-1 offered by B&C at:
>
> http://www.bandc.biz/S701-1.html
>
> and others.
>
> Bob . . .
>
>
Message 17
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| Subject: | Re: Watsonville Seminar Nov 8/9 |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 06:12 PM 10/23/2003 -0400, you wrote:
>--> AeroElectric-List message posted by: David.Shani@sanmina-sci.com
>
>Hi Bob,
>
>I am an EAA Chapter 119 member...and I did not hear a thing about your
>seminar coming to Watsonville Nov 8th.
>Where are you going to conduct the seminar - I know of quit a few people
>that will be interested...
>
>Thanks
>
>David Shani
>Email: david.shani@sanmina-sci.com
Our seminar schedule is always posted months in advance
at http://www.aeroelectric.com/whatsnew.html
Dave has a big hangar for us to use so there's plenty
of room. I would appreciate it if you'd pass the word.
Thanks!
Bob . . .
Message 18
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 03:16 PM 10/23/2003 +0100, you wrote:
>--> AeroElectric-List message posted by: "Steve Sampson"
><SSampson.SLN21@london.edu>
>
>Bob - thanks for that. In that case I will get a S701-1.
>
>But for my education, why cant I use the VANS 3 terminal unit? Surely it is
>internally wired as in the top right of the attached diag. with the coil
>between the third terminal and the case which is grounded to the firewall?
>Doesnt energising the coil, terminal to case pull the contactor in, and vica
>versa? (If the diag. does not go through matronics, it is yours and
>labelled - 'OV protection for built in regulator 1.0' It appears to have the
>filename 'bleadov.pdf' which I suspect is your name for it.)
To use a contactor with coil internally connected to the BAT
terminal, you need to pull to ground to close the contactor . . .
like for the battery master. Your alternator control leads is
a pull up to bus to turn the alternator on. To satisfy both of
these conditions, you would have to have a 3-pole DC PWR master
wired like:
http://www.aeroelectric.com/temp/sampson.gif
By going to a 4-terminal contactor, you can make both alternator
AND contactor operate by pulling up to bus with one pole of a two
pole master switch.
Bob . . .
Message 19
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 06:44 PM 10/23/2003 -0400, you wrote:
>--> AeroElectric-List message posted by: dschaefer1@kc.rr.com
>
>Bob .. this may be a stupid question .. but.. I've got a couple of 28 volt
>items in my panel (MFD). I've got a commercial 28 volt 'booster' from KGS
>Electrics I'm going to power a 6 fuse '28v bus'. What fuses do I use in
>this bus? Are they the same as 12v amperage-wise?
They're whatever you would use if the device is powered
from a 28v supply. This data should be available from the
manufacturer of the device. Generally speaking, 28 volt
fuses are 1/2 the size of fuses for the same device in a
14 volt version . . . but not always. Check with manufacturer
for recommended protection or do your own measurements on
a functioning system.
Bob . . .
Message 20
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--> AeroElectric-List message posted by: "David Swartzendruber" <dswartzendruber@earthlink.net>
I interpreted the question a little differently than Bob. The 5A blade fuse
you buy from your local automotive supplier is a 5A fuse regardless whether
is used in a 12V system or 24V system.
Dave in Wichita
> >
> >Bob .. this may be a stupid question .. but.. I've got a couple of 28
volt
> >items in my panel (MFD). I've got a commercial 28 volt 'booster' from
KGS
> >Electrics I'm going to power a 6 fuse '28v bus'. What fuses do I use in
> >this bus? Are they the same as 12v amperage-wise?
>
> They're whatever you would use if the device is powered
> from a 28v supply. This data should be available from the
> manufacturer of the device. Generally speaking, 28 volt
> fuses are 1/2 the size of fuses for the same device in a
> 14 volt version . . . but not always. Check with manufacturer
> for recommended protection or do your own measurements on
> a functioning system.
>
> Bob . . .
>
Message 21
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| Subject: | Nav/Loc/GS and Comm antennae internally mounted |
--> AeroElectric-List message posted by: "Treff, Arthur" <Arthur.Treff@Smartm.com>
All,
I would love to imbed the Comm, Nav/Loc/GS antennae in the fiberglass wing tips
of my RV-8. I the slight research I have done, a foil Nav ant seems well suited
to glass wing tip duty, but I have not seen any reviews of this same wing
tip-mounted antenna when used for Loc/GS duty. Additionally, there seem to be
mixed reviews of the foil Comm being hid beneath a wingtip on metal planes. Van's
published an article years ago about the performance of a Comm ant glued
to the windscreen, wherein they said performance was wonderful, however, said
xmitting put a squeal into the headsets. I am radio ignorant. I desire good
radio performance for instrument work, and I do not believe that a few antennae
will slow me down more than a knot or two. However, I know plastic plane guys
do really well with concealed antennae. Any thoughts out there?
Art Treff
Rv-8 Fastback (wiring)
Message 22
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--> AeroElectric-List message posted by: "Robinson, Chad" <crobinson@rfgonline.com>
Bob, speaking of contactors, what do they weigh? It's a small part of the setup,
I know, but I've been considering things like ground power jacks and such and
would like to at least have the datum tracked, since I'm going to all the trouble
to track everything else.
Regards,
Chad
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