AeroElectric-Archive.digest.vol-bx
April 14, 2003 - April 24, 2003
about not being hip with the latest good-thing-to-do; so another
handful of floobydust has been stirred into the fertile
ground of folklore.
Bob . . .
________________________________________________________________________________
| From: | "Alex Peterson" <alexpeterson(at)usjet.net> |
| Subject: | dual power and ground wires |
> >The instructions for my Icom A-200 say that I should run two 20awg
> >wires for the power and two for the ground. Why would I do
> that? John
> >Slade Cozy IV
>
> Yeah, the Microair guys are asking for that too. I wrote to them
> and asked for an explanation with no response yet. 20AWG is 10
> milliohms per foot. The average feeder from bus to radio
> is probably
> no more than 4' for 40 mohms total. A second lead in parallel is
> going to drop it to 20 . . . ????
>
> Beats me . . .
>
> Somebody might have some notions about "reliability" but if you
> have one wire come loose, how will you know that you've now
> reduced your wiring reliability by a factor of two?
>
> We wired a lot of radios with a single power supply and
> ground wire over the years. Maybe there's some heretofore
> ignored reason for doing it but nothing I can deduce.
> I'll ask around some more.
>
> I'll bet somebody did it, others noticed, everybody worried
> about not being hip with the latest good-thing-to-do; so another
> handful of floobydust has been stirred into the fertile
> ground of folklore.
Could it be that the wire size needed is too large for the connector
pins? I think that is what I concluded on my KY97A. Seems pretty dumb,
but IIRC, I immediately ran the two wires together into a larger wire
and on to the fuse. Might be a 28/14 volt thing. Seems like I recall
that the largest wire into the pin wasn't sized large enough for the
transmit current draw (although I would have no problems with the
transient load of transmitting, the wire wouldn't be properly
protected).
Alex Peterson
Maple Grove, MN
RV6-A N66AP 291 hours
www.rvforum.org
www.usfamily.net/web/alexpeterson
________________________________________________________________________________
| Subject: | Regulator/Rectifier for PM Alternator |
Anybody know of a source for information on the workings of
regulator/rectifiers for permanent magnet alternators? The rectifier part
isn't too hard, but how do they regulate voltage? Apparently there are
several types.
Dan Horton
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
| Subject: | dual power and ground wires |
> Yeah, the Microair guys are asking for that too. I wrote to them
> and asked for an explanation with no response yet. 20AWG is 10
> milliohms per foot. The average feeder from bus to radio is probably
> no more than 4' for 40 mohms total. A second lead in parallel is
> going to drop it to 20 . . . ????
Thanks.
Actually I misstated. The instructions call for 2 * 18AWG.
John Slade
________________________________________________________________________________
| From: | "Tom Schiff" <tomschiff(at)attbi.com> |
| Subject: | 110V Ball switch |
Try Radio Shack. They have switches that are used for burglar alarms.
Might not have enough current carrying capacity so you may want to put
in a relay. They also have magnetic switches for the same purpose one of
them may also work.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
TSaccio(at)aol.com
Subject: Re: AeroElectric-List: 110V Ball switch
I realize that this is off the beaten path but maybe some could help me.
I'm
looking for a 110 V ball switch that I could mount on a Bifold door.
It's
function would be to turn a light on and off in a closet by opening and
closing the door.
If you know where a switch like this could be found please let me know.
Already tried Mouser, Digi-key, MPJA and McMaster-Carr.
Thanks,
Tom Saccio
tsaccio(at)aol.com
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: dual power and ground wires |
In a message dated 4/14/03 8:32:39 AM Central Daylight Time,
sladerj(at)bellsouth.net writes:
> > Yeah, the Microair guys are asking for that too. I wrote to them
> > and asked for an explanation with no response yet. 20AWG is 10
> > milliohms per foot. The average feeder from bus to radio is probably
> > no more than 4' for 40 mohms total. A second lead in parallel is
> > going to drop it to 20 . . . ????
> Thanks.
> Actually I misstated. The instructions call for 2 * 18AWG.
> John Slade
>
Good Morning John,
For What It's Worth, my Trimble 2000 Approach Plus calls for two power and
two ground pins. They are to be jumpered right at the pins. I assume that
is to allow maximum contact via the small leaf style pins. I have further
assumed they did that primarily because there are more pins in the connector
than are needed for the application. Could be that I have assumed wrong.
Anybody know for sure?
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | Jim Oke <wjoke(at)shaw.ca> |
| Subject: | Re: dual power and ground wires |
The explanation that I was given by the avionics shop that wired my KY-97A
was that a single connector "pin" (actually a PCB edge connector) could not
reliably carry the max current needed (presumably on transmit). The
schematic called for two wires going to two separate pins which then joined
internal to the radio, thus halving the effective current carried per pin
down to something more reasonable. (This would also provide a degree of
redundancy to the power supply - this was not stated as a reason though).
By this rationale, power per pin is the important factor not wire size.
Presumably a single heavier wire could be wired to a tee splice feeding the
two pins. Do the ICOM and Microair schematics use two power and ground pins
or two wires entering at the same pin? If the former, then perhaps the
"power per pin" rationale is being used by these two manufacturers as well.
Jim Oke
RV-6A (taxi tests)
Winnipeg, MB
----- Original Message -----
From: "Alex Peterson" <alexpeterson(at)usjet.net>
Subject: RE: AeroElectric-List: dual power and ground wires
>
> > >The instructions for my Icom A-200 say that I should run two 20awg
> > >wires for the power and two for the ground. Why would I do
> > that? John
> > >Slade Cozy IV
> >
> > Yeah, the Microair guys are asking for that too. I wrote to them
> > and asked for an explanation with no response yet. 20AWG is 10
> > milliohms per foot. The average feeder from bus to radio
> > is probably
> > no more than 4' for 40 mohms total. A second lead in parallel is
> > going to drop it to 20 . . . ????
> >
> > Beats me . . .
> >
> > Somebody might have some notions about "reliability" but if you
> > have one wire come loose, how will you know that you've now
> > reduced your wiring reliability by a factor of two?
> >
> > We wired a lot of radios with a single power supply and
> > ground wire over the years. Maybe there's some heretofore
> > ignored reason for doing it but nothing I can deduce.
> > I'll ask around some more.
> >
> > I'll bet somebody did it, others noticed, everybody worried
> > about not being hip with the latest good-thing-to-do; so another
> > handful of floobydust has been stirred into the fertile
> > ground of folklore.
>
> Could it be that the wire size needed is too large for the connector
> pins? I think that is what I concluded on my KY97A. Seems pretty dumb,
> but IIRC, I immediately ran the two wires together into a larger wire
> and on to the fuse. Might be a 28/14 volt thing. Seems like I recall
> that the largest wire into the pin wasn't sized large enough for the
> transmit current draw (although I would have no problems with the
> transient load of transmitting, the wire wouldn't be properly
> protected).
>
> Alex Peterson
> Maple Grove, MN
> RV6-A N66AP 291 hours
> www.rvforum.org
> www.usfamily.net/web/alexpeterson
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | dual power and ground wires |
>
> > Yeah, the Microair guys are asking for that too. I wrote to them
> > and asked for an explanation with no response yet. 20AWG is 10
> > milliohms per foot. The average feeder from bus to radio is probably
> > no more than 4' for 40 mohms total. A second lead in parallel is
> > going to drop it to 20 . . . ????
>Thanks.
>Actually I misstated. The instructions call for 2 * 18AWG.
Hmmmm . . . extraordinarily mystifying . . .
Bob . . .
________________________________________________________________________________
| Subject: | Re: Master Switch |
I think you have reversed pins 4 and 5, pin 4 should go to the voltage reg
and pin 5 should go to the main bus (fuse block in my case). At least mine
works correctly as wired this way.
Harry Crosby
Pleasanton, California
RV-6, firewall forward
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
| Subject: | dual power and ground wires |
> By this rationale, power per pin is the important factor not wire size.
I see some sense in this argument, except that the instructions also have me
jumper ing four power pins together. (and 4 grounds) They say I can use the
same breaker, but that two pairs of 18awg should be run to the breaker.
________________________________________________________________________________
| From: | Randy Pflanzer <F1Rocket(at)comcast.net> |
| Subject: | TruTrak Autopilot Install |
Both the installation guide and the operation manual for the TruTrak
autopilot indicates the need for a "Autopilot Master Switch". To quote
the instructions:
"Aircraft electrical systems can generate voltage transients during an
engine start, and like other avionics systems, the autopilot should not
be subjected unnecessarily to these conditions."
Given the recent discussion regarding this topic, I would rather not
install another switch in my panel and introduce another point of
failure in my electrical system. Has anyone flying a TruTrak system
installed theirs sans the switch?
I'm tempted to forego the switch but I also don't want to fry $7K of
electronics and find the warranty voided because I didn't follow the
instructions.
Randy
F1 Rocket
http://mywebpages.comcast.net/f1rocket/
________________________________________________________________________________
| From: | "rondefly" <rondefly(at)pacbell.net> |
Hi, I sent an email to FADEC asking about their ignition system for a 0-200
and they told me you have to buy the hole bird. How do you get the system by
itself?
Ron Triano
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: TruTrak Autopilot Install |
Here in Houston there was an airplane lost (or at least heavily damaged)
because the autopilot was on during takeoff. As soon as the wheels left the
ground the airplane went into a steep bank. It was a C-172 if I remember
right. Whether the autopilot was powered because of pilot error or
mechanical malfuction is still out for debate but I decided that I wanted to
make sure that during takeoff and landing that there was no power to the
autopilot. Regardless of it's ability to live with these mysterious
'voltage transients' I want the power OFF to the autopilot when I am close
to the ground.
This switch would be dedicated to the autopilot, not an 'Avionics Master.'
So it is not a single point of failure for anything other than the
autopilot. At least that is the way that I'm going to wire it up.
Just something else to think about.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
----- Original Message -----
From: "Randy Pflanzer" <F1Rocket(at)comcast.net>
Subject: AeroElectric-List: TruTrak Autopilot Install
>
> Both the installation guide and the operation manual for the TruTrak
> autopilot indicates the need for a "Autopilot Master Switch". To quote
> the instructions:
>
> "Aircraft electrical systems can generate voltage transients during an
> engine start, and like other avionics systems, the autopilot should not
> be subjected unnecessarily to these conditions."
>
> Given the recent discussion regarding this topic, I would rather not
> install another switch in my panel and introduce another point of
> failure in my electrical system. Has anyone flying a TruTrak system
> installed theirs sans the switch?
>
> I'm tempted to forego the switch but I also don't want to fry $7K of
> electronics and find the warranty voided because I didn't follow the
> instructions.
>
> Randy
> F1 Rocket
> http://mywebpages.comcast.net/f1rocket/
>
>
________________________________________________________________________________
| From: | "Alex Peterson" <alexpeterson(at)usjet.net> |
| Subject: | TruTrak Autopilot Install |
I agree - I put a separate disconnect switch for the A/P. Initially, I
made sure this was off during all low altitude ops, but haven't turned
it off for a long time now. I do, however, have an avionics master
switch. I have this switch mainly for laziness - I don't want to have
to wander around the panel turning stuff on after startup, and I don't
want the battery loaded with it during start. It isn't a single point
of failure, because I can feed the avionics bus with the essential bus
switch also.
Alex Peterson
Maple Grove, MN
RV6-A N66AP 291 hours
www.rvforum.org
www.usfamily.net/web/alexpeterson
> -----Original
> This switch would be dedicated to the autopilot, not an
> 'Avionics Master.' So it is not a single point of failure for
> anything other than the autopilot. At least that is the way
> that I'm going to wire it up.
>
________________________________________________________________________________
| From: | Randy Pflanzer <F1Rocket(at)comcast.net> |
| Subject: | Re: TruTrak Autopilot Install |
The way I read it, you want to power up the AP while on the ground so
it can find it's bearings and set itself. The AP is still disengaged
as noted by the "AP OFF" in the window. So even if I install a AP
Master switch, I would only turn it off when starting and then
immediately turn it on. Part of the checklist would include "Verify
autopilot disengaged".
I still don't see any value to the switch. Appreciate your comments
Phil. BTW, I love your web site. Nice job.
Randy
F1 Rocket
http://mywebpages.comcast.net/f1rocket/
----- Original Message -----
From: Phil Birkelbach <phil(at)petrasoft.net>
Date: Monday, April 14, 2003 1:24 pm
Subject: Re: AeroElectric-List: TruTrak Autopilot Install
>
> Here in Houston there was an airplane lost (or at least heavily
> damaged)because the autopilot was on during takeoff. As soon as
> the wheels left the
> ground the airplane went into a steep bank. It was a C-172 if I
> rememberright. Whether the autopilot was powered because of pilot
> error or
> mechanical malfuction is still out for debate but I decided that I
> wanted to
> make sure that during takeoff and landing that there was no power
> to the
> autopilot. Regardless of it's ability to live with these mysterious
> 'voltage transients' I want the power OFF to the autopilot when I
> am close
> to the ground.
>
> This switch would be dedicated to the autopilot, not an 'Avionics
> Master.'So it is not a single point of failure for anything other
> than the
> autopilot. At least that is the way that I'm going to wire it up.
>
> Just something else to think about.
>
> Godspeed,
>
> Phil Birkelbach - Houston Texas
> RV-7 N727WB (Reserved) - Fuselage
> http://www.myrv7.com
>
> ----- Original Message -----
> From: "Randy Pflanzer" <F1Rocket(at)comcast.net>
> To:
> Subject: AeroElectric-List: TruTrak Autopilot Install
>
>
>
> >
> > Both the installation guide and the operation manual for the TruTrak
> > autopilot indicates the need for a "Autopilot Master Switch".
> To quote
> > the instructions:
> >
> > "Aircraft electrical systems can generate voltage transients
> during an
> > engine start, and like other avionics systems, the autopilot
> should not
> > be subjected unnecessarily to these conditions."
> >
> > Given the recent discussion regarding this topic, I would rather not
> > install another switch in my panel and introduce another point of
> > failure in my electrical system. Has anyone flying a TruTrak system
> > installed theirs sans the switch?
> >
> > I'm tempted to forego the switch but I also don't want to fry
> $7K of
> > electronics and find the warranty voided because I didn't follow the
> > instructions.
> >
> > Randy
> > F1 Rocket
> > http://mywebpages.comcast.net/f1rocket/
> >
> >
>
>
> _-
>
======================================================================_-
= - The AeroElectric-List Email Forum -
> _-
>
======================================================================_-
= !! NEWish !!
> _-
>
======================================================================_-
= List Related Information
> _-
> ======================================================================
>
>
>
>
________________________________________________________________________________
| From: | Randy Pflanzer <F1Rocket(at)comcast.net> |
| Subject: | Re: TruTrak Autopilot Install |
Regardless of which bus is providing power, how do you get around a
failed switch? I think that is the reason not to install the switch in
the first place. You just know that when it fails, you will be IFR in
the soup.
I agree about the convenience of an avionics master switch, but I
haven't yet decided on that one. Thanks for your thoughts Alex.
Randy
F1 Rocket
http://mywebpages.comcast.net/f1rocket/
----- Original Message -----
From: Alex Peterson <alexpeterson(at)usjet.net>
Date: Monday, April 14, 2003 1:46 pm
Subject: RE: AeroElectric-List: TruTrak Autopilot Install
>
> I agree - I put a separate disconnect switch for the A/P.
> Initially, I
> made sure this was off during all low altitude ops, but haven't turned
> it off for a long time now. I do, however, have an avionics master
> switch. I have this switch mainly for laziness - I don't want to have
> to wander around the panel turning stuff on after startup, and I don't
> want the battery loaded with it during start. It isn't a single point
> of failure, because I can feed the avionics bus with the essential bus
> switch also.
>
> Alex Peterson
> Maple Grove, MN
> RV6-A N66AP 291 hours
> www.rvforum.org
> www.usfamily.net/web/alexpeterson
>
>
> > -----Original
> > This switch would be dedicated to the autopilot, not an
> > 'Avionics Master.' So it is not a single point of failure for
> > anything other than the autopilot. At least that is the way
> > that I'm going to wire it up.
> >
>
>
> _-
>
======================================================================_-
= - The AeroElectric-List Email Forum -
> _-
>
======================================================================_-
= !! NEWish !!
> _-
>
======================================================================_-
= List Related Information
> _-
> ======================================================================
>
>
>
>
________________________________________________________________________________
| From: | "Rogers, Bob J." <BRogers(at)fdic.gov> |
| Subject: | Reverse Polarity Switch |
I am planning to install an electric linear actuator to control my cowl flap
on the Mustang II that I am building. The actuator is just a motor-driven
tube that runs one direction (extends) when the positive and ground wires
are each connected to the specified attach poles on the motor, and runs the
opposite direction (retracts) when the wires and polarity are reversed. I
want to mount a switch on the instrument panel that will extend the actuator
when I move the switch to the down position and will retract the actuator
when I move the switch to the up position. The actuator has built in limit
switches to make it automatically stop when it gets to the end of its range
of motion.
Can you please tell me what kind of switch will cause the polarity of this
electric motor to be reversed and how it should be wired? A diagram would
be helpful.
________________________________________________________________________________
| From: | RSwanson <rswan19(at)comcast.net> |
| Subject: | Re: Reverse Polarity Switch |
You need a double throw double pole switch. The actuator leads go to the
center pins and the positive and negative go to the top and bottom pins.
You just need to jumper the power leads so they end up being on opposite
sides on the top and bottom. ie. X them with a positive and negative on
the top and bottom.
Hope this helps.
R
----- Original Message -----
From: "Rogers, Bob J." <BRogers(at)fdic.gov>
Subject: AeroElectric-List: Reverse Polarity Switch
>
>
> I am planning to install an electric linear actuator to control my cowl
flap
> on the Mustang II that I am building. The actuator is just a
motor-driven
> tube that runs one direction (extends) when the positive and ground wires
> are each connected to the specified attach poles on the motor, and runs
the
> opposite direction (retracts) when the wires and polarity are reversed.
I
> want to mount a switch on the instrument panel that will extend the
actuator
> when I move the switch to the down position and will retract the actuator
> when I move the switch to the up position. The actuator has built in
limit
> switches to make it automatically stop when it gets to the end of its
range
> of motion.
>
> Can you please tell me what kind of switch will cause the polarity of
this
> electric motor to be reversed and how it should be wired? A diagram
would
> be helpful.
>
>
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | TruTrak Autopilot Install |
Not to argue against you or anything, as I totally agree. However, I'd
like to point out a nice feature of the TruTrak line of autopilots is
that the will disengage below a certain speed that you set. For
example, you can program it where it won't engage until you are at 90
knots. Anway, no big deal, just a nice feature the TruTrak offers. Too
bad we can't put real autopilots into a Cessna. I certainly know that
the junk JUNK Navomatic 400B in our C182RG that I fly would be better
left in the hanger than in the airplane :)
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Phil
Birkelbach
Subject: Re: AeroElectric-List: TruTrak Autopilot Install
Here in Houston there was an airplane lost (or at least heavily damaged)
because the autopilot was on during takeoff. As soon as the wheels left
the
ground the airplane went into a steep bank. It was a C-172 if I
remember
right. Whether the autopilot was powered because of pilot error or
mechanical malfuction is still out for debate but I decided that I
wanted to
make sure that during takeoff and landing that there was no power to the
autopilot. Regardless of it's ability to live with these mysterious
'voltage transients' I want the power OFF to the autopilot when I am
close
to the ground.
This switch would be dedicated to the autopilot, not an 'Avionics
Master.'
So it is not a single point of failure for anything other than the
autopilot. At least that is the way that I'm going to wire it up.
Just something else to think about.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
----- Original Message -----
From: "Randy Pflanzer" <F1Rocket(at)comcast.net>
Subject: AeroElectric-List: TruTrak Autopilot Install
>
> Both the installation guide and the operation manual for the TruTrak
> autopilot indicates the need for a "Autopilot Master Switch". To
quote
> the instructions:
>
> "Aircraft electrical systems can generate voltage transients during an
> engine start, and like other avionics systems, the autopilot should
not
> be subjected unnecessarily to these conditions."
>
> Given the recent discussion regarding this topic, I would rather not
> install another switch in my panel and introduce another point of
> failure in my electrical system. Has anyone flying a TruTrak system
> installed theirs sans the switch?
>
> I'm tempted to forego the switch but I also don't want to fry $7K of
> electronics and find the warranty voided because I didn't follow the
> instructions.
>
> Randy
> F1 Rocket
> http://mywebpages.comcast.net/f1rocket/
>
>
________________________________________________________________________________
| From: | Kevin Horton <khorto1537(at)rogers.com> |
| Subject: | Re: Reverse Polarity Switch |
>
>
>I am planning to install an electric linear actuator to control my cowl flap
>on the Mustang II that I am building. The actuator is just a motor-driven
>tube that runs one direction (extends) when the positive and ground wires
>are each connected to the specified attach poles on the motor, and runs the
>opposite direction (retracts) when the wires and polarity are reversed. I
>want to mount a switch on the instrument panel that will extend the actuator
>when I move the switch to the down position and will retract the actuator
>when I move the switch to the up position. The actuator has built in limit
>switches to make it automatically stop when it gets to the end of its range
>of motion.
>
>Can you please tell me what kind of switch will cause the polarity of this
>electric motor to be reversed and how it should be wired? A diagram would
>be helpful.
This sounds exactly like what you would need to run an electric flap
system on RVs. You should be able to use the same sort of circuit.
See:
http://www.aeroelectric.com/articles/flaps.pdf
Another example, slightly harder to figure out:
http://rv8asite.homestead.com/flapswitch.html
Good luck,
--
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | TruTrak Autopilot Install |
As Bob typically says, if its something that is essential for flight, it
should be backed up. If you HAVE to have an autopilot when you are in
IFR, you should have an alternate source for power to it. (I don't HAVE
to have an AP...I'd like to have one, but I'd hate to depend on it...if
I ever find myself solely depending on an AP in while in IFR, I'd quit
flying IFR until I felt I could fly it myself) So, if you have to have
it, back its power source up.
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Randy
Pflanzer
Subject: Re: RE: AeroElectric-List: TruTrak Autopilot Install
Regardless of which bus is providing power, how do you get around a
failed switch? I think that is the reason not to install the switch in
the first place. You just know that when it fails, you will be IFR in
the soup.
I agree about the convenience of an avionics master switch, but I
haven't yet decided on that one. Thanks for your thoughts Alex.
Randy
F1 Rocket
http://mywebpages.comcast.net/f1rocket/
----- Original Message -----
From: Alex Peterson <alexpeterson(at)usjet.net>
Date: Monday, April 14, 2003 1:46 pm
Subject: RE: AeroElectric-List: TruTrak Autopilot Install
>
> I agree - I put a separate disconnect switch for the A/P.
> Initially, I
> made sure this was off during all low altitude ops, but haven't turned
> it off for a long time now. I do, however, have an avionics master
> switch. I have this switch mainly for laziness - I don't want to have
> to wander around the panel turning stuff on after startup, and I don't
> want the battery loaded with it during start. It isn't a single point
> of failure, because I can feed the avionics bus with the essential bus
> switch also.
>
> Alex Peterson
> Maple Grove, MN
> RV6-A N66AP 291 hours
> www.rvforum.org
> www.usfamily.net/web/alexpeterson
>
>
> > -----Original
> > This switch would be dedicated to the autopilot, not an
> > 'Avionics Master.' So it is not a single point of failure for
> > anything other than the autopilot. At least that is the way
> > that I'm going to wire it up.
> >
>
>
> _-
>
======================================================================_-
= - The AeroElectric-List Email Forum -
> _-
>
======================================================================_-
= !! NEWish !!
> _-
>
======================================================================_-
= List Related Information
> _-
> ======================================================================
>
>
>
>
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | TruTrak Autopilot Install |
Not to argue against you or anything, as I totally agree. However, I'd
like to point out a nice feature of the TruTrak line of autopilots is
that the will disengage below a certain speed that you set. For
example, you can program it where it won't engage until you are at 90
knots. Anway, no big deal, just a nice feature the TruTrak offers. Too
bad we can't put real autopilots into a Cessna. I certainly know that
the junk JUNK Navomatic 400B in our C182RG that I fly would be better
left in the hanger than in the airplane :)
BTW, I put a switch in that is a single point of failure for ONLY my
TruTrak autopilot. I can always get rid of the switch later by wiring
around it, but didn't want to struggle with trying to add it in later.
It's there, we'll see if I need it.
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Phil
Birkelbach
Subject: Re: AeroElectric-List: TruTrak Autopilot Install
Here in Houston there was an airplane lost (or at least heavily damaged)
because the autopilot was on during takeoff. As soon as the wheels left
the
ground the airplane went into a steep bank. It was a C-172 if I
remember
right. Whether the autopilot was powered because of pilot error or
mechanical malfuction is still out for debate but I decided that I
wanted to
make sure that during takeoff and landing that there was no power to the
autopilot. Regardless of it's ability to live with these mysterious
'voltage transients' I want the power OFF to the autopilot when I am
close
to the ground.
This switch would be dedicated to the autopilot, not an 'Avionics
Master.'
So it is not a single point of failure for anything other than the
autopilot. At least that is the way that I'm going to wire it up.
Just something else to think about.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
----- Original Message -----
From: "Randy Pflanzer" <F1Rocket(at)comcast.net>
Subject: AeroElectric-List: TruTrak Autopilot Install
>
> Both the installation guide and the operation manual for the TruTrak
> autopilot indicates the need for a "Autopilot Master Switch". To
quote
> the instructions:
>
> "Aircraft electrical systems can generate voltage transients during an
> engine start, and like other avionics systems, the autopilot should
not
> be subjected unnecessarily to these conditions."
>
> Given the recent discussion regarding this topic, I would rather not
> install another switch in my panel and introduce another point of
> failure in my electrical system. Has anyone flying a TruTrak system
> installed theirs sans the switch?
>
> I'm tempted to forego the switch but I also don't want to fry $7K of
> electronics and find the warranty voided because I didn't follow the
> instructions.
>
> Randy
> F1 Rocket
> http://mywebpages.comcast.net/f1rocket/
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | TruTrak Autopilot Install |
>
>
>As Bob typically says, if its something that is essential for flight, it
>should be backed up. If you HAVE to have an autopilot when you are in
>IFR, you should have an alternate source for power to it. (I don't HAVE
>to have an AP...I'd like to have one, but I'd hate to depend on it...if
>I ever find myself solely depending on an AP in while in IFR, I'd quit
>flying IFR until I felt I could fly it myself) So, if you have to have
>it, back its power source up.
. . . but is the single switch really the issue? Count all
the parts in the autopilot system, all of the moving parts,
electrical parts AND the power sources. Given that you're
going to maintain the battery well, it's probably the single
most reliable component in the system . . . if you have the
slightest worry about switches, you can always replace it
ever so often with another switch that has been "screened"
but what about all the goodies in the autopilot itself?
When I say "backup", I mean backup for the entire system,
not just one component of the system. Folks tend to worry
most about electrical power sources going down 'cause
that's what they read about most. YOUR airplane isn't
going to suffer a power failure . . .
The hand-held radios independently back up panel-mounts.
#1 com on main bus is backed up by #2 com on aux bus.
Right ignition backs up left ignition. In every case where
you have a valid backup . . . it's totally independent
of the "essential" system or it's not a backup.
Bob . . .
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: TruTrak Autopilot Install |
I have not gotten the controller yet for my TTAP so I didn't know it had to
be turned on on the ground. I don't like to think that this thing can't get
it's bearings while airborne. There may be a delay but you really need to
be able to reboot the thing in the air don't you?
If this AP is built like I think it is then the 'AP Off' in the window
simply means that the software inside the AP has the power turned off to the
Servo and is not actively trying to control anything. By trusting this you
are relying on that AP to not 'lose it's mind' for one reason or another.
As long as that autopilot has power and the microprocessor is processing
there is a chance that a malfunction (read software bug) could cause it to
go haywire. Those buttons on the front don't look like toggle switches and
I imagine that they are simply inputs to the microprocessor and as such they
can do strange things. I'll admit that the odds of this happening is
probably very close to zero. Chances are that you'll lose your engine
several times before this AP will fail in this way. But if it does fail I
want to be able to kill it, and I would prefer that it be dead anytime I am
close to the ground.
What I may do is use one of Bob K's 3 position progressive transfer
switches. Down=Off, Middle=Controller Only, Up= Servo and Controller. I
have not consulted with Tru-Trak about this (so I could be completely wrong)
and I am not trying to argue with anyone. I just want to give you something
else to think about. I write software for a living and if I had written the
code in that AP I'd still want a way to turn power to it off. If nothing
else a circuit breaker that I could pull.
In the grand scheme of things if you choose not to install that switch then
you will probably never regret it, and I may very well regret installing it,
who knows. When I get to that point I'll give Tru-Trak a call and get the
skinny on the inards of the unit, and then I'll be able to make a more
intelligent decision.
Oh and BTW thanks for the kind words on the website. I am glad you enjoy
it.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
----- Original Message -----
From: "Randy Pflanzer" <F1Rocket(at)comcast.net>
Subject: Re: AeroElectric-List: TruTrak Autopilot Install
>
> The way I read it, you want to power up the AP while on the ground so
> it can find it's bearings and set itself. The AP is still disengaged
> as noted by the "AP OFF" in the window. So even if I install a AP
> Master switch, I would only turn it off when starting and then
> immediately turn it on. Part of the checklist would include "Verify
> autopilot disengaged".
>
> I still don't see any value to the switch. Appreciate your comments
> Phil. BTW, I love your web site. Nice job.
>
> Randy
> F1 Rocket
> http://mywebpages.comcast.net/f1rocket/
>
>
> ----- Original Message -----
> From: Phil Birkelbach <phil(at)petrasoft.net>
> Date: Monday, April 14, 2003 1:24 pm
> Subject: Re: AeroElectric-List: TruTrak Autopilot Install
>
> >
> > Here in Houston there was an airplane lost (or at least heavily
> > damaged)because the autopilot was on during takeoff. As soon as
> > the wheels left the
> > ground the airplane went into a steep bank. It was a C-172 if I
> > rememberright. Whether the autopilot was powered because of pilot
> > error or
> > mechanical malfuction is still out for debate but I decided that I
> > wanted to
> > make sure that during takeoff and landing that there was no power
> > to the
> > autopilot. Regardless of it's ability to live with these mysterious
> > 'voltage transients' I want the power OFF to the autopilot when I
> > am close
> > to the ground.
> >
> > This switch would be dedicated to the autopilot, not an 'Avionics
> > Master.'So it is not a single point of failure for anything other
> > than the
> > autopilot. At least that is the way that I'm going to wire it up.
> >
> > Just something else to think about.
> >
> > Godspeed,
> >
> > Phil Birkelbach - Houston Texas
> > RV-7 N727WB (Reserved) - Fuselage
> > http://www.myrv7.com
> >
> > ----- Original Message -----
> > From: "Randy Pflanzer" <F1Rocket(at)comcast.net>
> > To:
> > Subject: AeroElectric-List: TruTrak Autopilot Install
> >
> >
> >
> > >
> > > Both the installation guide and the operation manual for the TruTrak
> > > autopilot indicates the need for a "Autopilot Master Switch".
> > To quote
> > > the instructions:
> > >
> > > "Aircraft electrical systems can generate voltage transients
> > during an
> > > engine start, and like other avionics systems, the autopilot
> > should not
> > > be subjected unnecessarily to these conditions."
> > >
> > > Given the recent discussion regarding this topic, I would rather not
> > > install another switch in my panel and introduce another point of
> > > failure in my electrical system. Has anyone flying a TruTrak system
> > > installed theirs sans the switch?
> > >
> > > I'm tempted to forego the switch but I also don't want to fry
> > $7K of
> > > electronics and find the warranty voided because I didn't follow the
> > > instructions.
> > >
> > > Randy
> > > F1 Rocket
> > > http://mywebpages.comcast.net/f1rocket/
> > >
> > >
> >
> >
> > _-
> >
> ======================================================================_-
> = - The AeroElectric-List Email Forum -
> > _-
> >
> ======================================================================_-
> = !! NEWish !!
> > _-
> >
> ======================================================================_-
> = List Related Information
> > _-
> > ======================================================================
> >
> >
> >
> >
>
>
________________________________________________________________________________
| From: | "William Slaughter" <willslau(at)alumni.rice.edu> |
If we're talking about the Aerosance FADEC unit, you don't. The acronym is
Full Authority Digital Engine Controller, and by definition includes the
fuel injection and ignition systems integrated under the control of the
engine management computer(s), just like late model cars. For a standalone
ignition system, Lightspeed is a good, but by no means the only bet.
William Slaughter
RV-8 IOF-360 FADEC
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
rondefly
Subject: AeroElectric-List: FADEC
Hi, I sent an email to FADEC asking about their ignition system for a 0-200
and they told me you have to buy the hole bird. How do you get the system by
itself?
Ron Triano
________________________________________________________________________________
| From: | "Sam Hoskins" <shoskins(at)Globaleyes.net> |
| Subject: | Permenant Magnet Alternetor question |
I'm working on my load analysis.
How much juice does the feed to the S704-1 relay use, in conjunction with
the B&C 200G? I see it's protected by a 5A breaker.
Thanks.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Permenant Magnet Alternetor question |
>
>
>I'm working on my load analysis.
>
>How much juice does the feed to the S704-1 relay use, in conjunction with
>the B&C 200G? I see it's protected by a 5A breaker.
0.1 amps. You could use smaller breaker but they tend
to be more expensive and 5A is fine.
Bob . . .
________________________________________________________________________________
| From: | Rino <lacombr(at)nbnet.nb.ca> |
| Subject: | Re: dual power and ground wires |
I once had a computer that gave me problems because the power pin on the
connector would become real hot, create resistance and hence a voltage
drop. I connected two other unused pins in parallel to solve the
problem.
Rino
BobsV35B(at)aol.com wrote:
>
>
> In a message dated 4/14/03 8:32:39 AM Central Daylight Time,
> sladerj(at)bellsouth.net writes:
>
> > > Yeah, the Microair guys are asking for that too. I wrote to them
> > > and asked for an explanation with no response yet. 20AWG is 10
> > > milliohms per foot. The average feeder from bus to radio is probably
> > > no more than 4' for 40 mohms total. A second lead in parallel is
> > > going to drop it to 20 . . . ????
> > Thanks.
> > Actually I misstated. The instructions call for 2 * 18AWG.
> > John Slade
> >
>
> Good Morning John,
>
> For What It's Worth, my Trimble 2000 Approach Plus calls for two power and
> two ground pins. They are to be jumpered right at the pins. I assume that
> is to allow maximum contact via the small leaf style pins. I have further
> assumed they did that primarily because there are more pins in the connector
> than are needed for the application. Could be that I have assumed wrong.
> Anybody know for sure?
>
> Happy Skies,
>
> Old Bob
________________________________________________________________________________
| From: | "rondefly" <rondefly(at)pacbell.net> |
Thanks William, I am thinking to use one of the mags along with electronic.
Ron Triano Quicker one Q-200, 90% Done with 90% to go
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
William Slaughter
Subject: RE: AeroElectric-List: FADEC
If we're talking about the Aerosance FADEC unit, you don't. The acronym is
Full Authority Digital Engine Controller, and by definition includes the
fuel injection and ignition systems integrated under the control of the
engine management computer(s), just like late model cars. For a standalone
ignition system, Lightspeed is a good, but by no means the only bet.
William Slaughter
RV-8 IOF-360 FADEC
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
rondefly
Subject: AeroElectric-List: FADEC
Hi, I sent an email to FADEC asking about their ignition system for a 0-200
and they told me you have to buy the hole bird. How do you get the system by
itself?
Ron Triano
________________________________________________________________________________
| From: | Rino <lacombr(at)nbnet.nb.ca> |
Real World Solutions makes a redundant controller specially for aircraft
use.
Rino
William Slaughter wrote:
>
>
> If we're talking about the Aerosance FADEC unit, you don't. The acronym is
> Full Authority Digital Engine Controller, and by definition includes the
> fuel injection and ignition systems integrated under the control of the
> engine management computer(s), just like late model cars. For a standalone
> ignition system, Lightspeed is a good, but by no means the only bet.
>
> William Slaughter
> RV-8 IOF-360 FADEC
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
> rondefly
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: FADEC
>
>
> Hi, I sent an email to FADEC asking about their ignition system for a 0-200
> and they told me you have to buy the hole bird. How do you get the system by
> itself?
>
> Ron Triano
>
--
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | TruTrak Autopilot Install |
It can get its bearing in the air, you just have to fly straight and
level for about 10 seconds. What you mention is not an issue when it
comes to calibration.
You are correct in your observations about the buttons on the front.
Hit the ON-OFF and it just goes into AP OFF mode, so you are spot on
about it just being logic to the uprocessor. A switch like you mention
might not be a bad idea. A simple ON-OFF toggle, after reading Bob's
post about the reliability of them, is probably a good bet at a minimum.
I have one in my panel that I can tinker with if you have any further
questions. I'm sure Jim Y. can answer any and all though.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Phil
Birkelbach
Subject: Re: AeroElectric-List: TruTrak Autopilot Install
I have not gotten the controller yet for my TTAP so I didn't know it had
to
be turned on on the ground. I don't like to think that this thing can't
get
it's bearings while airborne. There may be a delay but you really need
to
be able to reboot the thing in the air don't you?
If this AP is built like I think it is then the 'AP Off' in the window
simply means that the software inside the AP has the power turned off to
the
Servo and is not actively trying to control anything. By trusting this
you
are relying on that AP to not 'lose it's mind' for one reason or
another.
As long as that autopilot has power and the microprocessor is processing
there is a chance that a malfunction (read software bug) could cause it
to
go haywire. Those buttons on the front don't look like toggle switches
and
I imagine that they are simply inputs to the microprocessor and as such
they
can do strange things. I'll admit that the odds of this happening is
probably very close to zero. Chances are that you'll lose your engine
several times before this AP will fail in this way. But if it does fail
I
want to be able to kill it, and I would prefer that it be dead anytime I
am
close to the ground.
What I may do is use one of Bob K's 3 position progressive transfer
switches. Down=Off, Middle=Controller Only, Up= Servo and Controller.
I
have not consulted with Tru-Trak about this (so I could be completely
wrong)
and I am not trying to argue with anyone. I just want to give you
something
else to think about. I write software for a living and if I had written
the
code in that AP I'd still want a way to turn power to it off. If
nothing
else a circuit breaker that I could pull.
In the grand scheme of things if you choose not to install that switch
then
you will probably never regret it, and I may very well regret installing
it,
who knows. When I get to that point I'll give Tru-Trak a call and get
the
skinny on the inards of the unit, and then I'll be able to make a more
intelligent decision.
Oh and BTW thanks for the kind words on the website. I am glad you
enjoy
it.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
----- Original Message -----
From: "Randy Pflanzer" <F1Rocket(at)comcast.net>
Subject: Re: AeroElectric-List: TruTrak Autopilot Install
>
> The way I read it, you want to power up the AP while on the ground so
> it can find it's bearings and set itself. The AP is still disengaged
> as noted by the "AP OFF" in the window. So even if I install a AP
> Master switch, I would only turn it off when starting and then
> immediately turn it on. Part of the checklist would include "Verify
> autopilot disengaged".
>
> I still don't see any value to the switch. Appreciate your comments
> Phil. BTW, I love your web site. Nice job.
>
> Randy
> F1 Rocket
> http://mywebpages.comcast.net/f1rocket/
>
>
> ----- Original Message -----
> From: Phil Birkelbach <phil(at)petrasoft.net>
> Date: Monday, April 14, 2003 1:24 pm
> Subject: Re: AeroElectric-List: TruTrak Autopilot Install
>
> >
> > Here in Houston there was an airplane lost (or at least heavily
> > damaged)because the autopilot was on during takeoff. As soon as
> > the wheels left the
> > ground the airplane went into a steep bank. It was a C-172 if I
> > rememberright. Whether the autopilot was powered because of pilot
> > error or
> > mechanical malfuction is still out for debate but I decided that I
> > wanted to
> > make sure that during takeoff and landing that there was no power
> > to the
> > autopilot. Regardless of it's ability to live with these mysterious
> > 'voltage transients' I want the power OFF to the autopilot when I
> > am close
> > to the ground.
> >
> > This switch would be dedicated to the autopilot, not an 'Avionics
> > Master.'So it is not a single point of failure for anything other
> > than the
> > autopilot. At least that is the way that I'm going to wire it up.
> >
> > Just something else to think about.
> >
> > Godspeed,
> >
> > Phil Birkelbach - Houston Texas
> > RV-7 N727WB (Reserved) - Fuselage
> > http://www.myrv7.com
> >
> > ----- Original Message -----
> > From: "Randy Pflanzer" <F1Rocket(at)comcast.net>
> > To:
> > Subject: AeroElectric-List: TruTrak Autopilot Install
> >
> >
> >
> > >
> > > Both the installation guide and the operation manual for the
TruTrak
> > > autopilot indicates the need for a "Autopilot Master Switch".
> > To quote
> > > the instructions:
> > >
> > > "Aircraft electrical systems can generate voltage transients
> > during an
> > > engine start, and like other avionics systems, the autopilot
> > should not
> > > be subjected unnecessarily to these conditions."
> > >
> > > Given the recent discussion regarding this topic, I would rather
not
> > > install another switch in my panel and introduce another point of
> > > failure in my electrical system. Has anyone flying a TruTrak
system
> > > installed theirs sans the switch?
> > >
> > > I'm tempted to forego the switch but I also don't want to fry
> > $7K of
> > > electronics and find the warranty voided because I didn't follow
the
> > > instructions.
> > >
> > > Randy
> > > F1 Rocket
> > > http://mywebpages.comcast.net/f1rocket/
> > >
> > >
> >
> >
> > _-
> >
>
======================================================================_-
> = - The AeroElectric-List Email Forum -
> > _-
> >
>
======================================================================_-
> = !! NEWish !!
> > _-
> >
>
======================================================================_-
> = List Related Information
> > _-
> >
======================================================================
> >
> >
> >
> >
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: TruTrak Autopilot Install |
>
>
>I have not gotten the controller yet for my TTAP so I didn't know it had to
>be turned on on the ground. I don't like to think that this thing can't get
>it's bearings while airborne. There may be a delay but you really need to
>be able to reboot the thing in the air don't you?
>
>If this AP is built like I think it is then the 'AP Off' in the window
>simply means that the software inside the AP has the power turned off to the
>Servo and is not actively trying to control anything. By trusting this you
>are relying on that AP to not 'lose it's mind' for one reason or another.
>As long as that autopilot has power and the microprocessor is processing
>there is a chance that a malfunction (read software bug) could cause it to
>go haywire. Those buttons on the front don't look like toggle switches and
>I imagine that they are simply inputs to the microprocessor and as such they
>can do strange things. I'll admit that the odds of this happening is
>probably very close to zero. Chances are that you'll lose your engine
>several times before this AP will fail in this way. But if it does fail I
>want to be able to kill it, and I would prefer that it be dead anytime I am
>close to the ground.
We've spoken several times on the list about autopilot disconnect
switches. On the big fellers, this is a button on the wheel that
unlatches a relay to cut power to all electrically driven flight
surfaces.
As part of the pre-flight, all trims and a/p are checked. A/P
is checked OFF before takeoff. Depending on the a/p, one could
consider running servo power through the stick disconnect system
so that the rest of a/p electronics can stay active (like
for the NavAid which is a turn coordinator even when it's
not flying the airplane.
This is not so much an issue of having to fly the airplane
after a/p or trim failure as it is about making sure you
can turn things OFF when they mis-behave.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: TruTrak Autopilot Install |
>
>
>Here in Houston there was an airplane lost (or at least heavily damaged)
>because the autopilot was on during takeoff. As soon as the wheels left the
>ground the airplane went into a steep bank. It was a C-172 if I remember
>right. Whether the autopilot was powered because of pilot error or
>mechanical malfuction is still out for debate but I decided that I wanted to
>make sure that during takeoff and landing that there was no power to the
>autopilot. Regardless of it's ability to live with these mysterious
>'voltage transients' I want the power OFF to the autopilot when I am close
>to the ground.
Which is the way it should be. The pre-landing checklist on a bizjet
call for a/p off before entering the pattern if you're VFR. Only the
yaw damper stays on until right before touchdown.
I'm suspicious of the pilot's story . . . if that's what he is saying.
In any a/p equipped airplane, there is no way one could do a takeoff
without feeling the a/p's steering effort in the wheel long before
he reaches flying speed.
>This switch would be dedicated to the autopilot, not an 'Avionics Master.'
>So it is not a single point of failure for anything other than the
>autopilot. At least that is the way that I'm going to wire it up.
>
>Just something else to think about.
Even when the a/p is engaged, slip clutches allow pilot to
over-ride the limited servo authority. If anyone is blaming
the a/p for an airplane's demise, I think there is much we
don't know about the truth of the story.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: TruTrak Autopilot Install |
>
>Both the installation guide and the operation manual for the TruTrak
>autopilot indicates the need for a "Autopilot Master Switch". To quote
>the instructions:
>
>"Aircraft electrical systems can generate voltage transients during an
>engine start, and like other avionics systems, the autopilot should not
>be subjected unnecessarily to these conditions."
Hmmm . . . perhaps I need to write to Mr. Y and see what
his take is on nefarious spikes . . .
I think I'll do that.
Bob . . .
________________________________________________________________________________
| From: | Jim Bean <jim-bean(at)att.net> |
| Subject: | Re: AeroElectric-List Digest: 33 Msgs - 04/13/03 |
AeroElectric-List Digest Server wrote:
> From: Jerry2DT(at)aol.com
> Subject: AeroElectric-List: Redundant Ignitions
>
>
> Geoff & Bob...
>
> I am planning on an XP-360 for my RV6a and my thinking is that for the best
> redundancy I will go with Electronic Ignition on one side and a magneto on
> the other. The engine will then run with no electric power to it at all. It
> "seems" to me that this is every bit as safe as dual E.I.'s/dual batteries
> and/or alternators, and will be lighter overall. Is this idea screwy somehow?
> If so, please have at me... :)
>
That's my plan.
Jim Bean
RV-8
Engine Stuff
> Jerry Cochran
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Trutrak installation requirements |
Good morning Mr. Younkin,
By way of introduction, I am currently an electronics engineer with Raytheon
in Wichita, KS. I've been working in aviation electrical systems and
avionics off and on since 1961. About 1986, I started a small publishing
and consulting activity to support the owner built and maintained aircraft
(OBAM) market. A fair representation of this activity can be viewed at
your pleasure on our website at http://www.aeroelectric.com
I was working at Cessna in the late 60's when the avionics master
switch was born. Low voltage germanium power transistor were
showing up in the audio and power supply stages of Cessna's
infamous 300 Series transceivers. After a number of instances
of popped power transistors, someone decided that "spikes" from
the starter were killing the radios . . . and the avionics master
switch seemed to be a rational approach to mitigating this hazard.
In years since, DO-160 was generated (and revised 4 or 5 times)
to guide us in the task of making things electronic live in airplanes.
Over the years I've tested many products to the current requirements
of DO-160 with, I believe, reasonable success.
In nearly 30 years, I'm unaware of any failures to my designs (or
that of anyone else) attributable to nefarious spikes
that produced electrical stresses beyond the bounds described
by DO-160 testing. I've never found it necessary to tell a customer
that my products should be pampered in any way when they were
integrating the device into their airframe. Indeed, most customers
would have balked at the notion.
In retrospect, I now believe that low voltage during cranking
allowed power supply transistors to come out of saturation and
force them into a second-breakdown failure mode.
From time to time, I observe that suppliers to both the
certified and OBAM community admonish installers to power their
product from an "avionics bus" or other means intended to protect
the product from conditions that exist during engine cranking.
I've looked many times at the power quality of various aircraft
and to date, I've not been able to capture a real, killer-transient
in the wild. In my experience, the biggest noise problems on the bus
are usually offered by accessories other than starters. Alternators
are fitted with a fixed 5% pk-pk ripple. Power inverters, a/c compressor
drive motors and even turn coordinators have from time to time, presented
bigger problems for power quality than do starters.
A builder on the AeroElectric-List quoted from your installation
manual as follows:
"Aircraft electrical systems can generate voltage transients during an
engine start, and like other avionics systems, the autopilot should not
be subjected unnecessarily to these conditions."
I am writing to ask if you have either (1) identified some transient
condition that resides outside the envelope described by recommended
DO-160 qualification testing or (2) have put a product on the market
that is not intended to operate within the DO-160 envelope? If the
first condition is true, have you quantified the potential hazard(s)
with respect to energy content and waveshape? Further, how might
these hazards fall outside the capability of modern system design for
protective power conditioning?
If I've missed some fundamental aspect of behavior in the
DC power generation and distribution for airplanes, I'd be
pleased if you would enlighten me.
By the way, Gene Brown, formerly of EDO-Aire and presently with
Electromech Technologies say's "hello"! He had some interesting
stories to tell about you over lunch last Friday!
Kindest regards,
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
| Subject: | dual power and ground wires |
> I connected two other unused pins in parallel to solve the problem.
Yep. That seems to be what they're doing. They've got me jumping opposing
pins, 4 for ground, 4 for power, then taking one lead (they say two) from
the jumped connectors to the breaker / fuse / ground bus.
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
> Real World Solutions makes a redundant controller specially for aircraft
> use.
I have it. It has two computers, but they share some components (power
supply?) and there's only one feed. For true redundancy you'd need two of
these, but at $895 each that aint so bad.
________________________________________________________________________________
| From: | "William Bernard" <billbernard(at)worldnet.att.net> |
Thanks, in alphabetical order to Bob, Giles and Scott! The master switch now works
as advertised. All I had to do was switch the wires.
Thanks again.
Bill
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | dual power and ground wires |
>
> > By this rationale, power per pin is the important factor not wire size.
>I see some sense in this argument, except that the instructions also have me
>jumper ing four power pins together. (and 4 grounds) They say I can use the
>same breaker, but that two pairs of 18awg should be run to the breaker.
Hmmm . . . I've not installed a radio that uses the Amp-Leaf card
edge connectors in many years. I'd forgotten that some products
take main power and ground off etched circuit card edge fingers.
These pins are indeed at risk for overloading. I think we used
to figure a 2A limit per circuit (probably de-rated from the
published recommendations) to insure longevity in the airplane.
I haven't used this style of connector in a new design in a
very long time . . . the ubiquitous D-sub is a low cost, robust
and widely distributed product. A really good value from both
the engineering and economic perspective.
The paralleled wire and pin concept is what I used to replace what
used to be 200 cu-in and 5# combination relays into a 25 cu-in
and 0.5 pound solid state power controller for our latest target.
We also reduced the connector costs from $hundreds$ to the price
of 3, 37-pin D-subs. Some circuits carry up to 40A. This is done
with d-sub pins (rated at 5A) by paralleling 10 pins on the end
of 22AWG pigtails of about 12" each. The wire has a resistance
of 16 mohms per foot. This small but very significant wire
resistance is added in series with the resistance of each pin
(1 to 3 mohms) and swamps out pin-to-pin variations so that
the combination of pins will share the loads between them.
So, for radios that DO use the Amp-Leaf or similar card
edge connector for power, the multiple pinout makes sense
if the radio pushes more than a couple of amps through
the wire. But like the target power distribution cited
above, pigtails of 22AWG wire from each pin, 12" or so long
can be brought together into a butt-splice were the
conductor may carry on with a nominal sized wire for
the task . . . 20AWG for radios up to 7A is plenty,
18AWG for anything bigger. You do not need to run
a wire for each pin all the way to ground and/or
bus bar.
That still begs the question about radios like Microair
that draw about 1.5A in transmit . . . a single
D-sub pin is quite adequate to the task so paralleling
two pins doesn't make any sense and I will continue
to build our harnesses here with a single 20AWG
power and ground wire crimped into one of the two
pins provided.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: TruTrak Autopilot Install |
> >Here in Houston there was an airplane lost (or at least heavily damaged)
> >because the autopilot was on during takeoff. As soon as the wheels left
the
> >ground the airplane went into a steep bank. It was a C-172 if I remember
> >right. Whether the autopilot was powered because of pilot error or
> >mechanical malfuction is still out for debate but I decided that I wanted
to
> >make sure that during takeoff and landing that there was no power to the
> >autopilot. Regardless of it's ability to live with these mysterious
> >'voltage transients' I want the power OFF to the autopilot when I am
close
> >to the ground.
>
>
> Which is the way it should be. The pre-landing checklist on a bizjet
> call for a/p off before entering the pattern if you're VFR. Only the
> yaw damper stays on until right before touchdown.
>
> I'm suspicious of the pilot's story . . . if that's what he is saying.
> In any a/p equipped airplane, there is no way one could do a takeoff
> without feeling the a/p's steering effort in the wheel long before
> he reaches flying speed.
>
>
> >This switch would be dedicated to the autopilot, not an 'Avionics
Master.'
> >So it is not a single point of failure for anything other than the
> >autopilot. At least that is the way that I'm going to wire it up.
> >
> >Just something else to think about.
>
> Even when the a/p is engaged, slip clutches allow pilot to
> over-ride the limited servo authority. If anyone is blaming
> the a/p for an airplane's demise, I think there is much we
> don't know about the truth of the story.
>
> Bob . . .
>
A friend of mine had a similar incident in this same airplane a couple of
weeks before. He said right after takeoff the airplane just decided to find
a heading different than the one painted on the runway behind him. He was
able to wrestle the plane and made it a non-event. He assured me that he
had the autopilot off. He told the FBO about the problem and it was
allegedly checked out. (This is a rental plane) I didn't think much about
it at the time other than it was an interesting strory, but then a week or
so later the airplane wound up in the trees and the pilot told a similar
story.
I agree with you in that we don't know all the truth to the story, (I got
the crash story third hand) but it got me to thinking about confused
autopilots and is the reason I wrote these posts. There is no reason that
an autopilot coming on should cause any grief if you know what is going on
and react appropriately. Why the second pilot didn't react appropriately?
I don't know I suspect he was a low time student and just got flustered or
didn't quite have the skills to control it in that circumstance. I don't
know the facts I just thought the whole thing to be a healthy mental
exercise.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | BNC/TNC clamp and solder style installation |
>
>Comments/Questions: I have a "Clamp & Solder" style TNC threraded male
>connector that came with my Becker Transponder. (not bayonet)
>
>What is the assembly method and sequence of the nut, washer, gasket, cone,
>and body?
See:
http://216.55.140.222/articles/BNC_Install/BNC_Install1.jpg
http://216.55.140.222/articles/BNC_Install/BNC_Install2.jpg
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Outer jacket stripping of shielded wire |
I have another related question for you... Again, relying on your
experience, the topic this time is multi-conductor shielded Tefzel wire;
(1), 2, 3, & 4 conductor 20, 22 & 24 GA, for example. Can you suggest a
good strip tool for this stuff? As before, I tend to invest in good tooling
which accepts different strip dies, so something for the Stipmaster would
be great. I also have a variety of cartridges for the Ideal coax strip
tool, so something for it would be desirable as well. Or, of course, I'll
buy something else if you've had good experience with it.
The outer jacket of the single conductor and triple shielded
wires I use here strip reasonably well using the pvc dies
in a old stripmaster. I say reasonably 'cause they tear the
braid up to some degree. But when you're snipping away the
braid and twisting to accommodate a solder sleeve or other
shield termination technique, the "sloppy" strip job disappears
under the finished cover.
See:
http://www.aeroelectric.com/articles/pigtail/pigtail.html
My current technique is to "pinch" the insulator, flex to crack it all
around, then pull about a 3 1/2" section off. This is hard on the hands
after a day of intercom and radio stack wiring.. ;-) Sure would like to
pick up something a little nicer, easier, faster.
That works too . . . For stripping that much length, I use an Xacto
knife to slit the outer jacket. What ever damage you do to the braid
will be minimal and insignificant in the finished product.
Bob . . .
________________________________________________________________________________
| From: | richard(at)riley.net |
| Subject: | LED Overvoltage and color |
I'm working with an artist that says he's "overdriving" (I assume with
voltage) green LED's to get them to make a yellow-green color.
I thought I understood how LED's worked, and that their color was
determined by the chemistry at the junction and that voltage would vary the
brightness. Can anyone help?
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: RE: E.I. instruments need pampering? |
>
>Bob:
>
>You clearly have a great deal of practical experience in designing
>electric/electronic equipment to meet not only the requirements of
>DO-160, but also your own additional requirements (e.g. lightning) based
>on your experience.
The lighting tests have been part of DO-160 for many years . . .
>I would like to request (urge, beg?) you to share this knowledge with
>those of us who would like to try our hand at doing some of our own
>design work. For example, practical tips on power filtering and
>conditioning, including suggested parts and/or rules for part selection,
>rules for protecting various types of inputs and outputs, e.g.
>thermocouple, digital, high and low level analog, etc.
>
>I think this would make a great paper to add to your website, and
>perhaps a revenue source, like your existing aeroelectric notebook. I
>for one would be willing to purchase same.
>
>If such a resource already exists, please point me to it.
I'll see what I can do with this suggestion. I've got
a BUNCH of article topics to write on. Suggest you get
a copy of DO-160. The member price for base document
and all revisions is about $140. See http://www.rtca.org
If you'd like to order this document at the member price
(60% off non-member price) I can probably order it for
you through Raytheon.
The whole task is wrapped up in energy management. Identify
the antagonist and it's ability to propagate energy into
your product. Limit stress on your product by (1) increasing
input impedance so as to limit current from the stress or
(2) clamping the stress off at safe voltage levels using
any of the various transient mitigation products which include
transorbs, movs, or simple LRC networks. Sometimes it's
a combination of these techniques.
There's probably a suite of techniques commonly used for
various power, signal and control leads . . . I'll see
if I can put some reasonable bounds on a useful collection
of tricks to include in an article.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Dual E.I. bus configuration |
>
>
>Bob.
>
>In planning the electrical system for my RV-8, I was leaning heavily towards
>using the Aerosance FADEC to control the engine. However, after reading of the
>brownout problems during start, I'm now leaning towards dual Lightspeed
>ignitions instead.
Does your engine come with mags? Why not use them up? Put ONE
electronic ignition on and use up the mags before you put
the second electronic system one on . . .
>I'm planning a system based on drawing Z-13, with one battery and a backup
>SD-8
>alternator.
>
>With dual electronic ignitions, should I put both of them on the hot battery
>bus? Or should I put one on the hot battery bus and one on the essential bus?
I'd put dual electronic ignitions on the battery bus.
>The only reason I can see for splitting them is to prevent engine failure in
>the extremely remote chance that the short link between the battery and
>the hot
>battery bus is compromised somehow.
Yup, that piece of wire should have same order of reliability
as prop bolts . . .
>Speaking of short links... the asterisk label in your drawings indicates
>wiring
>lengths of 6" or less, with no protection for the wire. Is the assumption that
>no fusible link is required if the wire run is kept very short? Why 6" as
>opposed to any other number?
6" is the rule-of-thumb limit for unprotected wires in
certified ships. If you need to make it 8" or a foot . . .
so be it. Just take care to install in way that does not
put the wire at risk and keep length to practical minimum.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: LED Overvoltage and color |
>
>I'm working with an artist that says he's "overdriving" (I assume with
>voltage) green LED's to get them to make a yellow-green color
Probably CURRENT overdrive . . .
>I thought I understood how LED's worked, and that their color was
>determined by the chemistry at the junction and that voltage would vary the
>brightness. Can anyone help?
Intensity is obviously a function of current and for
some devices, perceived color changes too. I'm not sure
an instrumented analysis of output color would show much
shift but the eye is a super-wide range sensor that's
anything but linear.
Do you NEED a yellow-green device? There are red-green
leds that can be duty cycle mixed so as to produce full
range of colors between red and green which would include
a yellow-green.
Bob . . .
________________________________________________________________________________
| From: | Randy Pflanzer <F1Rocket(at)comcast.net> |
| Subject: | TruTrak Follow-up Question |
Bob,
I have an additional wiring question regarding my TruTrak (probably
applies to all APs). In the F1 Rocket, all the wires running fore and
aft have to meet up in one place to go through the spar. The TruTrak
manual specifically states to keep all stobe wires away from the servo
bundles because of power pulses in the stobe wires can interfere with
the signals in the servo bundle.
I have about a 2' section of tubing in which the power leads to the
strobe power pack and the leads from the power pack to the wings all
run parallel together with the servo bundle. Do I need to change this
and remove the strobe wires from the tube? I hate to rip all this out
but thought I'd ask first. Better to fix now rather than after I'm
flying.
Thanks again.
Randy
F1 Rocket
http://mywebpages.comcast.net/f1rocket/
________________________________________________________________________________
| Subject: | Rotax alternator ouput concern |
Hi Bob and all,
During the weekend I had the oppurtunity to Fly a Rotax 912 FK 9 ultralight.
Funny little aircraft with 100-110 kt cruise speed.
During the whole flight I watched the bus voltage on the small ULMIP German
integrated engine monitor.
Avionics : Becker VHF and XPDR, Handheld Garmin 295 GPS
Regulator : unknown model with no marking. Blue plastic potting, black heat
sink.
The results were as follows (radio on) :
Strobe only : 14 V
Idem plus RC Allen AH : 13.8 V
Above plus 55 watt headlight : 13.2-12.9 V
The Becker internal voltmeter constantly read 0.2 V below those values.
Question :
-With such a voltage variation when turning the gyro on, is the Rotax claim
of 18-20 amp output credible ?
Or is something wrong with the wiring ?
I would greatly appreciate any feedback from Rotax users since our project
will be using a rotax 914 with the same alternator ( but with a different
regulator). and we'll have a 2 amp always running fuel pump.
Thanks,
Gilles
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Rotax alternator ouput concern |
><Gilles.Thesee@ac-grenoble.fr>
>
>Hi Bob and all,
>
>During the weekend I had the oppurtunity to Fly a Rotax 912 FK 9 ultralight.
>Funny little aircraft with 100-110 kt cruise speed.
>During the whole flight I watched the bus voltage on the small ULMIP German
>integrated engine monitor.
>Avionics : Becker VHF and XPDR, Handheld Garmin 295 GPS
>Regulator : unknown model with no marking. Blue plastic potting, black heat
>sink.
>The results were as follows (radio on) :
>
>Strobe only : 14 V
>Idem plus RC Allen AH : 13.8 V
>Above plus 55 watt headlight : 13.2-12.9 V
Looks typical . . .
>The Becker internal voltmeter constantly read 0.2 V below those values.
Within the usual installation and manufacturing variations.
>Question :
>-With such a voltage variation when turning the gyro on, is the Rotax claim
>of 18-20 amp output credible ?
>Or is something wrong with the wiring ?
>
>I would greatly appreciate any feedback from Rotax users since our project
>will be using a rotax 914 with the same alternator ( but with a different
>regulator). and we'll have a 2 amp always running fuel pump.
Check the data supplied with your engine. Rotax has never
claimed that they could RUN 18A worth of stuff AND
charge a battery. With everything turned on, your
bus voltage is still higher than what the battery
will deliver power at . . . so the alternator IS
carrying 100% of ship's loads. However, if you
take off with an 80% battery and run lots of stuff
for duration of flight, then you might well land
with the battery still less than 100%.
Most airplanes with PM alternators as sole source of
engine driven power source would benefit from plug-in-
the wall battery maintainer and/or roof-top solar
charger. Unlike our brothers who drive Lycs with
belt driven alternators, the risk of putting the
airplane away with a less than 100% battery is
much higher when all you have is a PM alternator.
What you've described offers no reason to be concerned
but it vividly illustrates system limitations that
should be considered in your flight ops and maintenance
plans.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: TruTrak Follow-up Question |
>
>Bob,
>
>I have an additional wiring question regarding my TruTrak (probably
>applies to all APs). In the F1 Rocket, all the wires running fore and
>aft have to meet up in one place to go through the spar. The TruTrak
>manual specifically states to keep all stobe wires away from the servo
>bundles because of power pulses in the stobe wires can interfere with
>the signals in the servo bundle.
Does he make any distinction between strobe power
or flash tube wiring?
>I have about a 2' section of tubing in which the power leads to the
>strobe power pack and the leads from the power pack to the wings all
>run parallel together with the servo bundle. Do I need to change this
>and remove the strobe wires from the tube? I hate to rip all this out
>but thought I'd ask first. Better to fix now rather than after I'm
>flying.
Sounds like you're talking about the 14v power wire. Frankly,
the system should be able to live with any properly installed
strobe system (no grounds on remote ends of bundles to
generate ground loops). I think you can leave it alone.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Rotax alternator ouput concern |
Bob,
Thank you.
> >
> >I would greatly appreciate any feedback from Rotax users since our
project
> >will be using a rotax 914 with the same alternator ( but with a different
> >regulator). and we'll have a 2 amp always running fuel pump.
>
> Check the data supplied with your engine. Rotax has never
> claimed that they could RUN 18A worth of stuff AND
> charge a battery. With everything turned on, your
> bus voltage is still higher than what the battery
> will deliver power at . . . so the alternator IS
> carrying 100% of ship's loads. However, if you
> take off with an 80% battery and run lots of stuff
> for duration of flight, then you might well land
> with the battery still less than 100%.
>
> Most airplanes with PM alternators as sole source of
> engine driven power source would benefit from plug-in-
> the wall battery maintainer and/or roof-top solar
> charger. Unlike our brothers who drive Lycs with
> belt driven alternators, the risk of putting the
> airplane away with a less than 100% battery is
> much higher when all you have is a PM alternator.
>
> What you've described offers no reason to be concerned
> but it vividly illustrates system limitations that
> should be considered in your flight ops and maintenance
> plans.
The load analysis I made for VFR cruise gives 10-11 amps with all permanent
loads on except the 33 watt landing light and instruments lights.
Thus I was expecting to have some headroom to give the batteries some
charge.
I have the feeling we NEED to pamper that aux battery to have a chance to
keep the mill running should the alternator quit.
Cheers,
Gilles
________________________________________________________________________________
| From: | <ktlkrn(at)cox.net> |
| Subject: | Nav/Strobe lights |
My Aerocomp project will be here soon and one the first things I need to do is
outfit the quick build wings with conduit and set up for the Nav and Strobe lights.
I have looked at the Whelens but they seem pricey at roughly $800 for the
complete system. The Aeroflash system seems worthy at around $500.
These seem to be the main two. Are there alternatives? Where is the best place
to purchase?
Darwin N. Barrie
Chandler AZ
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Of line until Monday |
Dee and I are launching for New Orleans in the morning. Will
be off line until Monday.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | Duncan McBride <duncanmcbride(at)comcast.net> |
| Subject: | Re: Nav/Strobe lights |
Search the RV archives for the discussions about the relative merits,
brightness and conformity of the two units. I ended up going with the
Aeroflash units. They are quality units and haven't given a bit of trouble.
I have no idea if the Whelens are significantly brighter. I got the
Aeroflash units from Lockwood Aviation - they're like neighbors here in
Florida.
----- Original Message -----
From: <ktlkrn(at)cox.net>
Subject: AeroElectric-List: Nav/Strobe lights
>
> My Aerocomp project will be here soon and one the first things I need to
do is outfit the quick build wings with conduit and set up for the Nav and
Strobe lights. I have looked at the Whelens but they seem pricey at roughly
$800 for the complete system. The Aeroflash system seems worthy at around
$500.
>
> These seem to be the main two. Are there alternatives? Where is the best
place to purchase?
>
> Darwin N. Barrie
> Chandler AZ
>
>
________________________________________________________________________________
| From: | richard(at)riley.net |
| Subject: | Re: Nav/Strobe lights |
Having put the Whelen (aviation unit, single flash) and the Aeroflash
(double flash) side by side, the Whelen was significantly brighter.
>
>
>Search the RV archives for the discussions about the relative merits,
>brightness and conformity of the two units. I ended up going with the
>Aeroflash units. They are quality units and haven't given a bit of trouble.
>I have no idea if the Whelens are significantly brighter. I got the
>Aeroflash units from Lockwood Aviation - they're like neighbors here in
>Florida.
>
>----- Original Message -----
>From: <ktlkrn(at)cox.net>
>To:
>Subject: AeroElectric-List: Nav/Strobe lights
>
>
> >
> > My Aerocomp project will be here soon and one the first things I need to
>do is outfit the quick build wings with conduit and set up for the Nav and
>Strobe lights. I have looked at the Whelens but they seem pricey at roughly
>$800 for the complete system. The Aeroflash system seems worthy at around
>$500.
> >
> > These seem to be the main two. Are there alternatives? Where is the best
>place to purchase?
> >
> > Darwin N. Barrie
> > Chandler AZ
> >
> >
>
>
________________________________________________________________________________
| From: | Jerzy Krasinski <krasinski(at)direcway.com> |
| Subject: | Re: LED Overvoltage and color |
richard(at)riley.net wrote:
>
>I'm working with an artist that says he's "overdriving" (I assume with
>voltage) green LED's to get them to make a yellow-green color.
>
>I thought I understood how LED's worked, and that their color was
>determined by the chemistry at the junction and that voltage would vary the
>brightness. Can anyone help?
>
>
Materials expand with temperature, and greater distance between atoms
in a crystalline lattice typically results in lower energy of the
bandgap. Therefore the hot diode produces lower energy photons, i.e.
shifted towards red part of the spectrum. Most likely you would not
notice this effect for a red diode, in red the eye is not very sensitive
to the wavelength change. It just happens that the eye is very sensitive
to wavelength in the yellow/green part of the spectrum.
The other part of the story is that you have to strongly overdrive the
diode and get it quite hot in order to see that effect. And believe me,
the diode does not like it. But you can get a wavelength shift in the
opposite direction, i.e. towards blue by cooling the diode. Attach the
yellow diode to a Peltier cooler, or put it into a freezer, and you
will see a yellow diode turn green. In a lab in liquid helium you can
get quite dramatic color changes.
Jerzy
>
>
>
>
________________________________________________________________________________
| From: | "Jim V. Wickert" <JimW_btg(at)compuserve.com> |
| Subject: | Re: Nav/Strobe lights |
What are the relative power ratings? Are they quite different?
Jim Wickert Vision #159
________________________________________________________________________________
| From: | Rico Voss <vozzen(at)yahoo.com> |
| Subject: | Re: Nav/Strobe lights |
Sorry to revive the nearly dead horse, but...
I'm also looking at strobes and wing wiring, and am
also confused.
Yes, the Aeroflash are not as bright, as they put out
only 10 joules per flash -- half or less energy than
the Whelen. but they cost half as much... Wasn't it
Bob that commented that the regs require 20+ joules
per flash (based on the "400 effective candles"
wording)??
My question is:
Does the Airworthiness Cert. (Operating LImitations?)
declare that the aircraft is equipped to fly at night,
or does it say that it can be flown at night IF it
meets the lighting requirements. And how do the
Aeroflash units satisfy the requirement (some of
theirs are PMA), if 10 joules/flash isn't enough??
I've corresponded with the people that make Nova equip
-- emer vehicle power supplies, strobes, etc --
reasonably priced. (strobe.com, strobesnmore.com)
They're very interested in entering the non-certified
plane market as an alternative, but they need to know
the requirements.
Is there a simple explanation.??
--Richard
>Having put the Whelen (aviation unit, single flash)
> and the Aeroflash
> (double flash) side by side, the Whelen was
> significantly brighter.
>
>
> McBride
> >
> >
> >Search the RV archives for the discussions about
> the relative merits,
> >brightness and conformity of the two units. I
> ended up going with the
> >Aeroflash units. They are quality units and
> haven't given a bit of trouble.
> >I have no idea if the Whelens are significantly
> brighter. I got the
> >Aeroflash units from Lockwood Aviation - they're
> like neighbors here in
> >Florida.
> >
> >----- Original Message -----
> >From: <ktlkrn(at)cox.net>
> >To:
> >Subject: AeroElectric-List: Nav/Strobe lights
> >
> >
>
> > >
> > > My Aerocomp project will be here soon and one
> the first things I need to
> >do is outfit the quick build wings with conduit and
> set up for the Nav and
> >Strobe lights. I have looked at the Whelens but
> they seem pricey at roughly
> >$800 for the complete system. The Aeroflash system
> seems worthy at around
> >$500.
> > >
> > > These seem to be the main two. Are there
> alternatives? Where is the best
> >place to purchase?
> > >
> > > Darwin N. Barrie
> > > Chandler AZ
>
http://search.yahoo.com
________________________________________________________________________________
| From: | Randy Pflanzer <F1Rocket(at)comcast.net> |
| Subject: | Re: TruTrak Follow-up Question |
>
> >
> >Bob,
> >
> >I have an additional wiring question regarding my TruTrak (probably
> >applies to all APs). In the F1 Rocket, all the wires running
> fore and
> >aft have to meet up in one place to go through the spar. The TruTrak
> >manual specifically states to keep all stobe wires away from the
> servo>bundles because of power pulses in the stobe wires can
> interfere with
> >the signals in the servo bundle.
>
> Does he make any distinction between strobe power
> or flash tube wiring?
The instructions refer to both. In my installation, I have both the
power and ground wires to the power pack and the output wires from the
power pack to the flash tubes running in the same conduit with servo
wire bundle.
>
> >I have about a 2' section of tubing in which the power leads to the
> >strobe power pack and the leads from the power pack to the wings all
> >run parallel together with the servo bundle. Do I need to change
> this>and remove the strobe wires from the tube? I hate to rip all
> this out
> >but thought I'd ask first. Better to fix now rather than after I'm
> >flying.
>
> Sounds like you're talking about the 14v power wire. Frankly,
> the system should be able to live with any properly installed
> strobe system (no grounds on remote ends of bundles to
> generate ground loops). I think you can leave it alone.
It is both wires and I guess I'm more concerned with the stobe output
wires to the flash tube. I have the strobe wires grounded per the
instructions. (Ground at the power pack, not connected at the flash
tube end.
Randy
F1 Rocket
http://mywebpages.comcast.net/f1rocket/
________________________________________________________________________________
| From: | "Sam Hoskins" <shoskins(at)Globaleyes.net> |
| Subject: | Nav/Strobe lights |
I am looking at the Nova too, specifically the Nova Micro-Pak. See it here:
http://www.strobe.com/products/micropak.htm
I am liking it because it looks like it is smaller and lighter weight, yet
only draws 4.5A. It is a plain-jane powersupply without a lot of unneeded
stuff.
I believe Bob said you need at least 20 Joules per flash.
Sam
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Rico
Voss
Subject: Re: AeroElectric-List: Nav/Strobe lights
Sorry to revive the nearly dead horse, but...
I'm also looking at strobes and wing wiring, and am
also confused.
Yes, the Aeroflash are not as bright, as they put out
only 10 joules per flash -- half or less energy than
the Whelen. but they cost half as much... Wasn't it
Bob that commented that the regs require 20+ joules
per flash (based on the "400 effective candles"
wording)??
My question is:
Does the Airworthiness Cert. (Operating LImitations?)
declare that the aircraft is equipped to fly at night,
or does it say that it can be flown at night IF it
meets the lighting requirements. And how do the
Aeroflash units satisfy the requirement (some of
theirs are PMA), if 10 joules/flash isn't enough??
I've corresponded with the people that make Nova equip
-- emer vehicle power supplies, strobes, etc --
reasonably priced. (strobe.com, strobesnmore.com)
They're very interested in entering the non-certified
plane market as an alternative, but they need to know
the requirements.
Is there a simple explanation.??
--Richard
>Having put the Whelen (aviation unit, single flash)
> and the Aeroflash
> (double flash) side by side, the Whelen was
> significantly brighter.
>
>
> McBride
> >
> >
> >Search the RV archives for the discussions about
> the relative merits,
> >brightness and conformity of the two units. I
> ended up going with the
> >Aeroflash units. They are quality units and
> haven't given a bit of trouble.
> >I have no idea if the Whelens are significantly
> brighter. I got the
> >Aeroflash units from Lockwood Aviation - they're
> like neighbors here in
> >Florida.
> >
> >----- Original Message -----
> >From: <ktlkrn(at)cox.net>
> >To:
> >Subject: AeroElectric-List: Nav/Strobe lights
> >
> >
>
> > >
> > > My Aerocomp project will be here soon and one
> the first things I need to
> >do is outfit the quick build wings with conduit and
> set up for the Nav and
> >Strobe lights. I have looked at the Whelens but
> they seem pricey at roughly
> >$800 for the complete system. The Aeroflash system
> seems worthy at around
> >$500.
> > >
> > > These seem to be the main two. Are there
> alternatives? Where is the best
> >place to purchase?
> > >
> > > Darwin N. Barrie
> > > Chandler AZ
>
http://search.yahoo.com
________________________________________________________________________________
| From: | Rico Voss <vozzen(at)yahoo.com> |
| Subject: | Nav/Strobe lights |
Yes, but as I understand it, these supplies would send
too much power to the Aeroflash strobe heads that can
only handle 10 joules. Which begs the question: Are
all the Aeroflash units blinking out there technically
legal?? Or shouldn't I be asking??
> I am looking at the Nova too, specifically the Nova
> Micro-Pak. See it here:
> http://www.strobe.com/products/micropak.htm
>
> I am liking it because it looks like it is smaller
> and lighter weight, yet
> only draws 4.5A. It is a plain-jane powersupply
> without a lot of unneeded
> stuff.
>
> I believe Bob said you need at least 20 Joules per
> flash.
>
>
http://search.yahoo.com
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
Bob,
I have a question about the PIDG Crimper from B&C.
I have an AMP ratchet crimper I got at Sun & Fun. It's jaws are about 1/8
wide. Will I get the same results with this, or do I need to spend the $40?
Regards,
John Slade
________________________________________________________________________________
| From: | "Clay Smith" <cbsmith(at)nf.sympatico.ca> |
>
>
>Hi Bob,
>I did build my own Crowbar following your schematic diagram. I first
>bench tested the circuit using a variable power supply and set the trip
>voltage to 16.2 V as you recommended. The circuit seemed to be operating
>perfectly. So, I installed the unit in my panel and further tested with a
>small, very old, ATV battery. Now I'm getting a lot of false trips when
>turning switches from on to off. I allowed the battery to drain down to
>about 10 to 11 and even tried re-adjusting the trip point of the
>OVM. Still the same. My guess is that I'm getting a quick positive
>voltage spike when I remove a load (switch off) from the battery, so for
>trouble-shooting purposes I tried putting a 100 uf electrolytic cap across
>the terminals. This did eliminated the false trips...? So do you think
>my circuit is defective? Shouldn't it be able to ignore these spikes?
>Perhaps these spikes are normal and my old battery doesn't have enough
>capacity ? FWIW, I'm using all polyfuses in my panel an!
>d the OVM is tripping a 5 amp polyfuse. Any suggestions would be
>appreciated.
Try a smaller bypass . . . 100uf is a tad heavy. A 10uF tantalum
would be about right if you want to put it right in the crowbar
ovm. Solder (+) to SCR anode, (-) to SCR cathode.
Alternatively, tying the 100uF capacitor to another protected
feed from the bus would be beneficial to both the OVM and
other devices in your system.
Bob . . .
Thanks Bob for your response. It doesn't sound like your too surprised to hear
about these false trips. I'll try your suggestions.
Clay
________________________________________________________________________________
| From: | "LarryRobertHelming" <lhelming(at)sigecom.net> |
| Subject: | Re: Nav/Strobe lights |
I like Strobes n More for strobe kits. They well both Whelan and Nova power
supply kits. I like the 90 watt 4 head x-pak with free switch and harness
for about $270. Includes four light heads complete with amp connectors and
4 x 15' power cables. I've been looking at these for a couple months now
and haven't seen anything that looks better so far for my money.
http://www.strobesnmore.com/
Larry in Indiana, RV7 Tip-up O-360 3XG reserved.
Working on Canopy of Finish Kit
----- Original Message -----
From: "Rico Voss" <vozzen(at)yahoo.com>
Subject: RE: AeroElectric-List: Nav/Strobe lights
>
>
> Yes, but as I understand it, these supplies would send
> too much power to the Aeroflash strobe heads that can
> only handle 10 joules. Which begs the question: Are
> all the Aeroflash units blinking out there technically
> legal?? Or shouldn't I be asking??
>
> > I am looking at the Nova too, specifically the Nova
> > Micro-Pak. See it here:
> > http://www.strobe.com/products/micropak.htm
> >
> > I am liking it because it looks like it is smaller
> > and lighter weight, yet
> > only draws 4.5A. It is a plain-jane powersupply
> > without a lot of unneeded
> > stuff.
> >
> > I believe Bob said you need at least 20 Joules per
> > flash.
> >
> >
>
> http://search.yahoo.com
>
>
________________________________________________________________________________
| From: | Neil Clayton <harvey4(at)earthlink.net> |
| Subject: | Re: Nav/Strobe lights |
But Larry.....what about the streamlined lenses for an airplane wingtip.
It's not clear from the "strobesnmore" website, but it looks like their
bulbs are just that - bulbs, with no lens covers. We'd have to fabricate
some kind of cover. This issue has been holding me up buying from them.
Neil
At 12:52 AM 4/17/03, you wrote:
>
>
>I like Strobes n More for strobe kits. They well both Whelan and Nova power
>supply kits. I like the 90 watt 4 head x-pak with free switch and harness
>for about $270. Includes four light heads complete with amp connectors and
>4 x 15' power cables. I've been looking at these for a couple months now
>and haven't seen anything that looks better so far for my money.
>
>http://www.strobesnmore.com/
>
>Larry in Indiana, RV7 Tip-up O-360 3XG reserved.
>Working on Canopy of Finish Kit
>----- Original Message -----
>From: "Rico Voss" <vozzen(at)yahoo.com>
>To:
>Subject: RE: AeroElectric-List: Nav/Strobe lights
>
>
> >
> >
> > Yes, but as I understand it, these supplies would send
> > too much power to the Aeroflash strobe heads that can
> > only handle 10 joules. Which begs the question: Are
> > all the Aeroflash units blinking out there technically
> > legal?? Or shouldn't I be asking??
> >
> > > I am looking at the Nova too, specifically the Nova
> > > Micro-Pak. See it here:
> > > http://www.strobe.com/products/micropak.htm
> > >
> > > I am liking it because it looks like it is smaller
> > > and lighter weight, yet
> > > only draws 4.5A. It is a plain-jane powersupply
> > > without a lot of unneeded
> > > stuff.
> > >
> > > I believe Bob said you need at least 20 Joules per
> > > flash.
> > >
> > >
> >
> > http://search.yahoo.com
> >
> >
>
>
________________________________________________________________________________
| From: | "LarryRobertHelming" <lhelming(at)sigecom.net> |
I am building an RV7 with enclosed wing tips. The strobe lights will fit, I
plan on it anyway, in there fine and not require additional cover. I may
need to come up with some type of form/structure for holding and attaching
the light bulb in the enclosed area of the wing tip. I will buy position
lights (for the red and green requirements) and a Whelan combo light for the
tail position. The x-pak should drive the Whelan tail light even though
different name brand. Nova and strobes-n-more use the same amp connectors
as Whelan. I will post my final results and thoughts on this after
installation.
Thanks, Neil, for pointing out your issue as it may be an important
consideration.
Larry in Indiana, RV7 Tip-up O-360 3XG reserved.
Working on Canopy of Finish Kit
----
>But Larry.....what about the streamlined lenses for an airplane wingtip.
It's not clear from the "strobesnmore" website, but it looks like their
bulbs are just that - bulbs, with no lens covers. We'd have to fabricate
some kind of cover. This issue has been holding me up buying from them.
Neil
________________________________________________________________________________
| From: | Jim McManus <jmcmanus(at)polarcom.com> |
| Subject: | Re: Rotax alternator ouput concern |
Gilles said
"I have the feeling we NEED to pamper that aux battery to have a chance
to
keep the mill running should the alternator quit."
The Rotax 912 does not require battery power to run - only to crank the
starter. The ignition modules are energized by what is essentially a
magneto ( or even two ) colocated with your alternator.
Jim McManus
________________________________________________________________________________
| Subject: | Re: Rotax alternator ouput concern |
----- Message d'origine -----
De : "Jim McManus"
:
Envoy : jeudi 17 avril 2003 07:02
Objet : AeroElectric-List: Re: Rotax alternator ouput concern
>
> Gilles said
>
> "I have the feeling we NEED to pamper that aux battery to have a
chance
> to
> keep the mill running should the alternator quit."
>
> The Rotax 912 does not require battery power to run - only to crank the
> starter. The ignition modules are energized by what is essentially a
> magneto ( or even two ) colocated with your alternator.
>
Jim,
Our airplane is powered by a Rotax 914 that DOES RELY on an electric main
pump to keep running.
Few people are aware of the fact, but the 914 IS electrically dependant.
Cheers,
Gilles
________________________________________________________________________________
| From: | "Roberto Giusti" <roby(at)mail.com> |
| Subject: | Nav/Strobe lights |
I contacted Nova and they said that I would get the absolute brightest
flash with their HPS4 power supply.
The spec sheet states 28.5 Joules primary flash and 12.5 joules
secondary flash in double flash mode.
In fact it is so powerful that it won't work with their standard heads.
They have special HPS heads (expensive and bulky), but on the phone they
said that whelen heads should cope with this supply.
So an option could be to use the Nova HPS4 power supply with Whelen
heads.
Roberto Giusti
RV8 QB Italy
roby(at)mail.com
________________________________________________________________________________
| From: | "Shaun Simpkins" <shauns(at)hevanet.com> |
| Subject: | Re: Nav/Strobe lights |
I obsessed about this subject a while ago. This is one of those subjects
that a homebuilder's FAQ should address.
Aeroflash strobes are, by their own admission, not compliant with today's
strobe output requirements. Bob is right, it takes nearly 20 joules AND a
concentrating lens like the ones that Whelen makes to meet the current
FAA regs.
If you're wanting to see a copy of the FAA regs, you can look up the page
in your Aircraft Spruce catalog, or browse the Whelen website. If you want
more detail, the FAA's website has tons of articles on lighting regs, definitions,
and measurement methods.
So why can Aeroflash continue to sell their product? In the certified market,
to replace preexisting Aeroflash units. There are scads of Aeroflash strobes
in all those pre-1980 Cessnas out there, and most every manufacturer at one
time or another used Aeroflash.
In the experimental market, it's often the case that those aircraft are not flown
at night and the strobes are being bought for daytime visibility enhancement.
There's no regs for daytime use of strobes. Inspectors often don't concentrate
on strobe output when there are far more pressing safety issues to be judged.
But if you want to be absolutely legal for night flight, Whelen equivalent strobes
and
power supplies are necessary. You'll notice that Cirrus and Lancair
both use Whelen. Those with 28V systems in Europe can use Bosch as well...
Shaun Simpkins
________________________________________________________________________________
| From: | "Timothy Freeze" <s35pilot(at)hotmail.com> |
| Subject: | Problem with Whelen Stobe - Help |
Hi,
I have the Whelen "a600" strobe and "hdacf" power supply on my cozy III. I
bought the supply early in the project and when I finally completed it the
supply had been sitting for 10 years!
I now have over 200 hours on the aircraft but when I first turn on the
strobe I can hear the charge and firing of the stobe. The noise goes away
after about 10 minutes. I thought perhaps the battery was not fully charged
or something like that so I put a trickle charger on the battery to see if
that cured it. Nope.
So I talked to the Whelen guy when I was at sun n fun and he said "The
supply was too old and needed work" & "It's out warrenty and the capacitors
were probably just old". He told me "It's cheaper to buy a new power
supply". I thanked him for his help and went in search of a replacment
supply. SHOCK AND AWE - well I priced it and it is $350 + shipping ...
ouch.
The whelen guy seemed kind of rude ... like he didn't really want to be at
the show listening to customers. I felt he just wanted me to go away, so I
didn't pester him. I just felt he wanted me to go away! He also didn't
inspire my confidence that he knew what he was talking about. Just a
feeling but I try to listen to them!
I really want to get this fixed - I'm tired of people telling me it sounds
like my ELT is going off when I key the mike after I first start off flying.
So I trun the stobe off and ask if they still hear it - nope. Then I tell
them I'm trying to fix it. I leave off the part about "I don't kanow how to
fix it". :-)
Since it is kind of a pain to remove the power supply (I have to take one
wing off as I put the supply in the strake), and possibly expensive, do you
think this is the problem or should I do more trouble shooting?
Can I just buy new capacitor(s) from Newark or Digikey and save a pile of
money? I know I can do the work as far as safely removing, discharging, and
replacing capacitors unless they are some weird electrical or physical
configuration and I can't get them commercially.
I've montored this list for a long time now. This is my first request for
help. I'd appreciate any shared thoughts, experience, or suggestions.
Thanks in advance.
Tim
Cozy N215TW
email at s35pilot(at)hotmail.com
________________________________________________________________________________
| From: | John & Amy Eckel <eckel1(at)comcast.net> |
| Subject: | Re: Nav/Strobe lights |
----- Original Message -----
From: "Shaun Simpkins" <shauns(at)hevanet.com>
Subject: Re: AeroElectric-List: Nav/Strobe lights
>
> I obsessed about this subject a while ago. This is one of those subjects
> that a homebuilder's FAQ should address.
>
> Aeroflash strobes are, by their own admission, not compliant with today's
> strobe output requirements. Bob is right, it takes nearly 20 joules AND a
> concentrating lens like the ones that Whelen makes to meet the current
> FAA regs.
>
> If you're wanting to see a copy of the FAA regs, you can look up the page
> in your Aircraft Spruce catalog, or browse the Whelen website. If you
want
> more detail, the FAA's website has tons of articles on lighting regs,
definitions,
> and measurement methods.
>
> So why can Aeroflash continue to sell their product? In the certified
market,
> to replace preexisting Aeroflash units. There are scads of Aeroflash
strobes
> in all those pre-1980 Cessnas out there, and most every manufacturer at
one
> time or another used Aeroflash.
> In the experimental market, it's often the case that those aircraft are
not flown
> at night and the strobes are being bought for daytime visibility
enhancement.
> There's no regs for daytime use of strobes. Inspectors often don't
concentrate
> on strobe output when there are far more pressing safety issues to be
judged.
>
> But if you want to be absolutely legal for night flight, Whelen equivalent
strobes and
> power supplies are necessary. You'll notice that Cirrus and Lancair
> both use Whelen. Those with 28V systems in Europe can use Bosch as
well...
>
> Shaun Simpkins
Shaun,
Thanks for clearing up this issue for me and doing the research.
I have often wondered about the legality of the Aeroflash strobes.
Thanks.
John, A230
>
>
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | Problem with Whelen Stobe - Help |
Maybe try calling Whelen and explaining the situation. If they think
its the power supply, tell them you'll buy a new power supply and change
it out, but if that doesn't fix it, you will expect a full refund. Or,
if you have a buddy that is building, just borrow his supply maybe and
try that out?
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Timothy Freeze
Subject: AeroElectric-List: Problem with Whelen Stobe - Help
Hi,
I have the Whelen "a600" strobe and "hdacf" power supply on my cozy III.
I
bought the supply early in the project and when I finally completed it
the
supply had been sitting for 10 years!
I now have over 200 hours on the aircraft but when I first turn on the
strobe I can hear the charge and firing of the stobe. The noise goes
away
after about 10 minutes. I thought perhaps the battery was not fully
charged
or something like that so I put a trickle charger on the battery to see
if
that cured it. Nope.
So I talked to the Whelen guy when I was at sun n fun and he said "The
supply was too old and needed work" & "It's out warrenty and the
capacitors
were probably just old". He told me "It's cheaper to buy a new power
supply". I thanked him for his help and went in search of a replacment
supply. SHOCK AND AWE - well I priced it and it is $350 + shipping ...
ouch.
The whelen guy seemed kind of rude ... like he didn't really want to be
at
the show listening to customers. I felt he just wanted me to go away,
so I
didn't pester him. I just felt he wanted me to go away! He also didn't
inspire my confidence that he knew what he was talking about. Just a
feeling but I try to listen to them!
I really want to get this fixed - I'm tired of people telling me it
sounds
like my ELT is going off when I key the mike after I first start off
flying.
So I trun the stobe off and ask if they still hear it - nope. Then I
tell
them I'm trying to fix it. I leave off the part about "I don't kanow how
to
fix it". :-)
Since it is kind of a pain to remove the power supply (I have to take
one
wing off as I put the supply in the strake), and possibly expensive, do
you
think this is the problem or should I do more trouble shooting?
Can I just buy new capacitor(s) from Newark or Digikey and save a pile
of
money? I know I can do the work as far as safely removing, discharging,
and
replacing capacitors unless they are some weird electrical or physical
configuration and I can't get them commercially.
I've montored this list for a long time now. This is my first request
for
help. I'd appreciate any shared thoughts, experience, or suggestions.
Thanks in advance.
Tim
Cozy N215TW
email at s35pilot(at)hotmail.com
________________________________________________________________________________
| From: | Michel Therrien <mtherr(at)yahoo.com> |
| Subject: | Re: Problem with Whelen Stobe - Help |
In my installation manual, it's written:
"WARNING: Strobe light power supplies are meant to be
used, not to remain in an inactive state. Any strobe
light power supply that has been out of service for a
long period of time is subject to failure because the
electrolytic condenser loses its polarity formation.
A strobe light power supply not having been used for
one year or longer is vulnerable to failure."
And the more interesting part:
"If this is the case, it is recommended to start
operating the system on a voltage that is reduced by
25% for 10 to 15 minutes before putting the power
supply into normal service. This will preven t
overheating of the condenser while they reform. If
the power supply, after a long period of non use, is
operated at full voltage immediately, there is an
excellent possibiliyt that the condenser will become
overheated."
--- Timothy Freeze wrote:
> Freeze"
>
> Hi,
>
> I have the Whelen "a600" strobe and "hdacf" power
> supply on my cozy III. I
> bought the supply early in the project and when I
> finally completed it the
> supply had been sitting for 10 years!
>
http://search.yahoo.com
________________________________________________________________________________
| From: | "Treff, Arthur" <Arthur.Treff(at)Smartm.com> |
'Letric Bob (and the list),
I'm putting together my power budget for my RV-8's electrical system. When I use
the max current draw shown on all the avionics specifications along with strobes,
landing and taxi lights and pitot heat, I'm up towards 60 amps! Clearly
I must be doing something wrong. Can you provide some guidance on how to size
an alternator and if there is a multiplier that is normally used to calculate
nominal current from the max that is published. It will be a basic IFR ship
with pitot heat and lights and Trutrack with alt hold.
For the GNS 430, for instance, Garmin tech support said that when the unit is just
receiving in cruise, expect 1.5 amps; during approach phase, when driving
needles and switching freq's and cursoring around, expect 3.0 amps. Then, when
the mic is keyed, ADD another 6 amps. This appears very high to me, as the
installation guide from Garmin specifies two inputs, each protected by a 5 amp
fuse.
With lighting, should I expect that the 100W landing light draws 8.3 amps at all
times, or is this an inrush current? Whelen strobe power supply says its rated
for 7 amps, is that the value I should put into my budget? I'm using a Piper
heated pitot/static mast, but have no clue how much it draws.
Most people I talk to say that a 40 amp alternator is more than most planes need.
Any comments on how to get me there?
Art Treff
RV-8
________________________________________________________________________________
| Subject: | Re: Power budget |
| From: | "Matt Prather" <mprather(at)spro.net> |
Art,
Please
see my comments below.
>
>
> 'Letric Bob (and the list),
>
> I'm putting together my power budget for my RV-8's electrical system.
> When I use the max current draw shown on all the avionics specifications
> along with strobes, landing and taxi lights and pitot heat, I'm up
> towards 60 amps! Clearly I must be doing something wrong. Can you
> provide some guidance on how to size an alternator and if there is a
> multiplier that is normally used to calculate nominal current from the
> max that is published. It will be a basic IFR ship with pitot heat and
> lights and Trutrack with alt hold.
>
When doing a power budget, you are most interested in the average
consumption. The max usage only really comes into play when
deciding how big the wire and breaker need to be.
> For the GNS 430, for instance, Garmin tech support said that when the
> unit is just receiving in cruise, expect 1.5 amps; during approach
> phase, when driving needles and switching freq's and cursoring around,
> expect 3.0 amps. Then, when the mic is keyed, ADD another 6 amps. This
> appears very high to me, as the installation guide from Garmin specifies
> two inputs, each protected by a 5 amp fuse.
6 Amps seems high for continuous transmit, as that would be 72W burned,
and at 50% efficiency ( a reasonable assumption for a transmitter) you would
radiate 36W. I didn't think any GA radios are putting out that much. A 6A
transient might be appropriate for figuring breaker size to avoid nuisance
trips.
For com radios, transponder, flap/trim/gear motors the standby current
can be used for power budget. The duty cycle operated at max current
rating is very low.
>
> With lighting, should I expect that the 100W landing light draws 8.3
> amps at all times, or is this an inrush current? Whelen strobe power
> supply says its rated for 7 amps, is that the value I should put into my
> budget? I'm using a Piper heated pitot/static mast, but have no clue
> how much it draws.
For lighting, you need to budget the bulb's rated demand. A 100W bulb
uses at least 8.3A continuous, probably more if you consider that by the
time you get to 12V, your LV light is flashing. If your alternator is
keeping
its end up, you are probably driving 13V to the bulb.
Bob (and I believe others) has shown an analysis of strobe power use.
Basically, you can take the energy (in Joules) of each flash and multiply
that
by the number of flashes per unit time to get the average wattage
>
> Most people I talk to say that a 40 amp alternator is more than most
> planes need. Any comments on how to get me there?
>
If you do the analysis based on the duty cycle of each device I think it
will all work out okay. Its not a problem if on a momentary basis your
alternator doesn't keep up. I'll bet that in most cars if you are out
driving
during a summer evening rain storm with the AC/defr, wipers and headlights
and then lower a window while sitting at a traffic light, you will dip into
the reserves that the battery supplies.
> Art Treff
> RV-8
>
>
Regards,
Matt-
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: Power budget |
I am no expert but I have been doing my power budget lately as well. I used
only continuous load numbers for devices that will be on together at any
given time. I didn't count the flap motor, or the trim servos. I didn't
include the power used during transmitting on the comm either. It is only
going to be for a few seconds and the Alt will have a chance to catch up
once I let go of the mic.
Use the max numbers for sizing wire and the continuous numbers for
alternator sizing. The idea is to only include loads that will be on
together in the airplane. For instance. I will flash my landing lights
during almost all operations this measn that only one will be on at a time
so I only include one lamp in my continuous load power budget for enroute
flight. When I enter the pattern to land at night both lights come on full
time, but the autopilot is not part of this load because I turned it off.
Yes the flap motor pulls 3A but why include it since it runs for about 30
seconds per flight. The battery is good for loads upwards of 200A.
The GNS 430 numbers that you gave sound a little conservative but probably
okay to use. The pitot heat will pull about 8Amps for every 100Watts of
heat it makes. I looked at Gretz Aero and his are between 8 and 12 Amps.
The 100Watt lamps will use up a little over 8 Amps continuously. P=VI.
Power(Watts) = Voltage(Volts) x Current(Amps) (DC power only)
So worst case is landing at night with the Pitot Heat on. Positon lights
(6A) Two 100W Landing lights (16A) Strobes (7A) and Pitot Heat (10A) you are
at 39Amps. I would imagine that you need a 60Amp alternator.
Leave yourself some room for battery charging too. If you are right on the
ragged edge there'll be no juice left to charge the battery.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
----- Original Message -----
From: "Treff, Arthur" <Arthur.Treff(at)Smartm.com>
Subject: AeroElectric-List: Power budget
>
> 'Letric Bob (and the list),
>
> I'm putting together my power budget for my RV-8's electrical system.
When I use the max current draw shown on all the avionics specifications
along with strobes, landing and taxi lights and pitot heat, I'm up towards
60 amps! Clearly I must be doing something wrong. Can you provide some
guidance on how to size an alternator and if there is a multiplier that is
normally used to calculate nominal current from the max that is published.
It will be a basic IFR ship with pitot heat and lights and Trutrack with alt
hold.
>
> For the GNS 430, for instance, Garmin tech support said that when the unit
is just receiving in cruise, expect 1.5 amps; during approach phase, when
driving needles and switching freq's and cursoring around, expect 3.0 amps.
Then, when the mic is keyed, ADD another 6 amps. This appears very high to
me, as the installation guide from Garmin specifies two inputs, each
protected by a 5 amp fuse.
>
> With lighting, should I expect that the 100W landing light draws 8.3 amps
at all times, or is this an inrush current? Whelen strobe power supply says
its rated for 7 amps, is that the value I should put into my budget? I'm
using a Piper heated pitot/static mast, but have no clue how much it draws.
>
> Most people I talk to say that a 40 amp alternator is more than most
planes need. Any comments on how to get me there?
>
> Art Treff
> RV-8
>
>
________________________________________________________________________________
| From: | BAKEROCB(at)aol.com |
| Subject: | Nav/Strobe lights |
IAeroElectric-List message previously posted by: Rico Voss
<< .....skip......My question is: Does the Airworthiness Cert. (Operating
LImitations?)
declare that the aircraft is equipped to fly at night, or does it say that
it can be flown at night IF it meets the lighting
requirements......skip.....--Richard >>
4/17/2003
Hello Richard, Here is an extract from my 4/13/2003 posting {...skip.... The
Operating Limitations for your specific aircraft should have some words in it
that read something like "After completion of Phase I flight testing, unless
appropriately equipped for night and/or instument flight in accordance with
91.205, this aircraft is to be operated under VFR, day only."
That means that once your aircraft is "appropriately equipped" and you have
the transponder, encoder, and altimeter inspections required for IFR
operations (and repeated every two years) you are good to go -- no "IFR
certification" regarding the avionics equipment installed is
involved**....skip.....}
So the same philosophy applies to the lighting required for night operations
-- the aircraft must be "appropriately equipped". In order to make that
determination one must dig into the FAR's and determine what is "appropriate"
in the eyes of the FAA. This subject has been written about before on the
list and you can search the archives as well as the FAR's to arrive at your
conclusion.
'OC' Baker, Builder of KIS TR-1 #116 4/14/97 - ?/?/?
________________________________________________________________________________
| From: | Jerzy Krasinski <krasinski(at)direcway.com> |
| Subject: | Re: Problem with Whelen Stobe - Help |
Timothy Freeze wrote:
> "....when I first turn on the strobe I can hear the charge and firing of the
stobe. The noise goes away after about 10 minutes...."
>
It is not clear to me what are the symptoms. Strobe power supplies are
always a little noisy. You can always hear high frequency ton of the
high voltage converter, and you can always hear a quiet and periodic
thumps when the strobe fires. Is that what you hear? If that is the case
I do not see much wrong, the sound of the converter sometimes can get
louder if a part of the laminated iron core gets loose.
Or do you hear not periodic and quite loud sound reminding a small
hammer strike against a metal, which typically happens without a flash.
That is most likely a sound of the capacitor breaking down. The
capacitor sometimes can get cured as described in another email by
running the strobe for some time at reduced voltage.
Or perhaps you hear it through the electrical installation in your
headphones? And what happens after those 10 minutes? Is the strobe still
working or it quits?
Jerzy
________________________________________________________________________________
| From: | "Richard Sipp" <rsipp(at)earthlink.net> |
| Subject: | Re: Power budget |
My RV-4 has the following electrical power consumers:
landing lights (big old GE bulbs)
nav lights
GPS/com
Nav/com
transponder
3 unit strobes
single cockpit flood led
cockpit lighting dimmer
VM1000 engine monitor
intercom
boost pump
When all of this is operating (not transmitting) the amp load on the VM1000
is stable at 27 amps.
I use a B&C 35 amp alternator. With the above load and 700 rpm the voltage
drops from the normal 14.3 to 13.9.
At any rpm above idle the voltage returns to 14.3. Normal day VFR cruise
load is about 15 amps.
Dick Sipp
RV4 N250DS
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | PM-OV and E-bus switch |
Geof,
I missed the response to your e-mail below. If you got one from Bob, and if
you saved it, could you fwd it to me? Thanks. I've just studied the Z-
diagrams in Aeroelectric Connection and re-read several chapters - I'm
jumping in with both feet to become "an aircraft electrical systems designer
(homebuilt)".
I liked your 2nd question, about effect of having e-bus alternate feed
switch on at same time battery switch was on. If it is true that there is
"no effect", then there is a significant implication: The e-bus alternate
feed switch could be left "on" all the time, in anticipation of a serious
malfunction requiring killing the "battery switch and main bus". That would
reduce the pilot actions from 2 to 1 - "turn off battery switch". You'd
eliminate "then turn on essential bus alternate feed". (I was going to keep
this "private" but because this system is being discussed on the list, I'll
send it to the list, also.)
David Carter
----- Original Message -----
From: "Geoff Evans" <hellothaimassage(at)yahoo.com>
Subject: AeroElectric-List: PM-OV and E-bus switch
>
> Bob. I sent this question to you via email, but perhaps it got lost by the
> wayside. I'll repeat the question here.
>
> I have a question about the B&C PM-OV 14 product.
>
> It looks like all the same stuff you recommed for protecting the SD-8
> alternator, except the relay has extra lugs on it for the light bulb. The
B&C
> website says that, if wired according to their diagram, that the light
will
> illuminate if the alternator switch is left off or if the crowbar trips.
>
> I think I understand how the circuit trips, but I don't understand why you
> would want a light that illuminates when the alternator is turned off...
> Assuming that I'm going to use the SD-8 as a backup alternator, and
following
> your advice about not putting two alternators on the same bus at the same
time,
> why would I want a light that functioned in this manner? The light would
be on
> for all normal operations.
>
> Perhaps this product is designed to be used with the SD-8 when it is the
only
> alternator in the airplane, or when it is running on a separate, isolated
> bus...
>
> ------
>
> On a totally different subject.. What happens in your Z-11 circuit
philosophy
> if the E-bus alternate feed switch is on at the same time the battery
master
> switch is on? It looks to me like absolutely nothing, but I just wanted to
make
> sure.
>
> Thanks.
> -Geoff
>
> RV-8 QB Fuselage
>
________________________________________________________________________________
| From: | Jim McManus <jmcmanus(at)polarcom.com> |
| Subject: | Re: Rotax alternator output concern |
Thanks Gilles - I'd forgotten about the 914 fuel pump.
Any idea if that pump could be added to a 912 as a backup ?
Jim
________________________________________________________________________________
| From: | "Gary K" <flyink(at)efortress.com> |
Hope this isn't too far off topic, I was ordering an ELT and got lost
comparing features. On three lower-end units from Spruce, there is one with
voice capability (AK-450), one that is satelite capable (ACK E-01), and one
that doesn't require an external antenna (EBC-102). I'm assuming each of
these features is mutually exclusive to each unit. There is also the remote
panel option on some of these. What is the satelite thing all about? Are
all rescue personnel able to get the satelite signal (is it worth getting)?
Any comments on any of these units? The AK-450 seems pretty popular and
that's what I was about to order but figured I'd try to learn more before
buying.
Thanks a bunch,
Gary (the last thing on my list to buy!) Krysztopik
Pelican PL w/subaru, 98% complete
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
| Subject: | Problem with strobe help |
There you have it, thanks to Michel -
"And the more interesting part:
"If this is the case, it is recommended to start operating the system on a voltage
that is reduced by 25% for 10 to 15 minutes before putting the power supply
into normal service. This will prevent overheating of the condenser while they
reform. If the power supply, after a long period of non use, is
operated at full voltage immediately, there is an excellent possibility that the
condenser will become overheated."
The fact is that many condensers are 'paste' or similar material which
requires a voltage across it to keep it polarised. As this disappears, it
slowly loses its effectiveness. This is true of radios, strobes or any article
requiring a capacitor input. The traditional way to overcome inactivity for say
a year or moe is to apply the alternating current at a very low voltage and
slowly build it up to operating standard. If the 'paste' is still viable it will
come back to normal. If that fails, one needs to test the capacitor out of
the circuit and usually to replace it. Hams replace capacitors at regular intervals
in equipment that is older but valuable. The same is true of Whelens, or
any other condenser-driven circuits.
Only a salesman interested in a % will advise to 'buy another' without
offering an honest alternate first.
Happy landings
Ferg
________________________________________________________________________________
If you are a member of AOPA check out this link in the AOPA Online Members
Only section: ELT, Phone Home
http://www.aopa.org/members/files/pilot/1997/elt9711.html
The last line in the article says everything you need to know..... "121.5
MHz ELTs are just about worthless," said NOAA's Lt. Mark Moran. "Just about
anything would be more effective." Not a very comforting thought. The
article explains the reasons in detail but essentially it says that the
121.5 MHz signals give locations that are rather imprecise, that the first
one of the seven search and rescue satellites in polar orbit may take up to
five hours to get within range, and that the ELT is most likely going to be
destroyed on impact. Unless you are willing to pay the much higher price
($2,800 versus less than $200 for a 121.5 MHz unit) for a 460 MHz ELT, it
would seem that the "best" ELT is the cheapest one broadcasting at 121.5,
there being no justification for buying an expensive 121.5 unit.
Best regards,
Rob Housman
Europa XS Tri-Gear A070
Airfarame complete
Irvine, CA
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Gary K
Subject: AeroElectric-List: ELT selection
Hope this isn't too far off topic, I was ordering an ELT and got lost
comparing features. On three lower-end units from Spruce, there is one with
voice capability (AK-450), one that is satelite capable (ACK E-01), and one
that doesn't require an external antenna (EBC-102). I'm assuming each of
these features is mutually exclusive to each unit. There is also the remote
panel option on some of these. What is the satelite thing all about? Are
all rescue personnel able to get the satelite signal (is it worth getting)?
Any comments on any of these units? The AK-450 seems pretty popular and
that's what I was about to order but figured I'd try to learn more before
buying.
Thanks a bunch,
Gary (the last thing on my list to buy!) Krysztopik
Pelican PL w/subaru, 98% complete
________________________________________________________________________________
| From: | "James E. Clark" <james(at)nextupventures.com> |
Dick's posting has some very IMPORTANT data to make a note of.
April 14, 2003 - April 24, 2003
AeroElectric-Archive.digest.vol-bx