AeroElectric-Archive.digest.vol-mh
March 12, 2014 - May 03, 2014
We had this conversation many moons ago after somebody
noticed that some high wing airplanes offered under-wing
courtesy lights. Then some other readers hypothesized about
baggage compartment lights on low wing airplanes that
could be exercised even with the master switch off.
The on-limit timer allows one to park the airplane
and perhaps even button up the cockpit while using
lights on the ship's battery to take care of final
chores outside.
I sketched an on-limit timer for somebody who was
interested in adding the feature his airplane but
I no longer recall his exact application.
The notion of an on-limit timer was never to
replace the forgetful pilot's remembering to
turn it off . . . but to be able to leave the
light on for convenience and have it go off by
itself after the task needing illumination
was completed.
Bob . . .
________________________________________________________________________________
Subject: | Re: Timer circuit for led array |
From: | David Duperron <davedup10(at)gmail.com> |
Thanks for the reply Jeff. Do you have any more info on the automotive
light delay relay? Dave Duperron (davedup10(at)gmail.com.
On Wed, Mar 12, 2014 at 1:06 PM, Jeff Luckey wrote:
> True but ...
>
> that overlooks the convenience of always-available cabin lighting without
> having the Master on.
>
> The post earlier today that referenced an existing automotive delay relay
> looks like a great solution - cheap, designed for the purpose, plug-n-play,
> no re-inventing the wheel
>
> - what don't we like about that
>
> -Jeff
>
> ------------------------------
> *From:* Eric M. Jones
> *To:* aeroelectric-list(at)matronics.com
> *Sent:* Wednesday, March 12, 2014 9:42 AM
> *Subject:* AeroElectric-List: Re: Timer circuit for led array
>
> emjones(at)charter.net>
>
>
> > Timer circuit for led array Reply with quote
> > I'm looking for a timer to shut off my cabin overhead utility light
> after about 10 minutes of operation. It's fed directly from the main
> battery buss and I would like to know that if I forgot to turn it off the
> timer would do it for me before draining the battery. Any ideas? David
> Duperron
>
>
> I learned to fly in Cessnas, and as I recall leaving the beacon on was a
> certain way to avoid walking away from the airplane with something still on.
> Perhaps the solution to your problem is just to have the cabin light on
> the same bus as the beacon.
>
> Adding an extra gizmo is not the best way to go.
>
> --------
> Eric M. Jones
> www.PerihelionDesign.com <http://www.periheliondesign.com/>
> 113 Brentwood Drive
> Southbridge, MA 01550
> (508) 764-2072
> emjones(at)charter.net
>
>
> Read this topic online here:
>
> http://forums.matronics.comnbsp;
>
>
> *
>
>
> *
>
>
________________________________________________________________________________
Subject: | Re: Timer circuit for led array |
From: | David Duperron <davedup10(at)gmail.com> |
Thanks for the tip DL, I will investigate further. Dave
On Wed, Mar 12, 2014 at 11:11 AM, D L Josephson wrote:
> dlj04(at)josephson.com>
>
> There are dome light timer relays for cars
> http://www.delcity.net/store/Time-Delay-Relay/p_804415.h_
> 804416.t_1.r_IF1003?gclid=COb_ieijjb0CFc1afgodbl0AUA
>
>
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Subject: | Re: Timer circuit for led array |
Dave,=0A=0AIn case you did not see DL Josepheson's earlier post, here is th
e link he provided:=0A=0Ahttp://www.delcity.net/store/Time-Delay-Relay/p_80
4415.h_804416.t_1.r_IF1003?gclid=COb_ieijjb0CFc1afgodbl0AUA=0A=0A=0AI don
't know anything more about the relay than what's shown at that link, but I
imagine using the relay is pretty straightforward.- If you have specific
questions, I and other listers will be happy to try and answer them.=0A=0A
-Jeff=0A=0A=0A=0A________________________________=0A From: David Duperron <
davedup10(at)gmail.com>=0ATo: aeroelectric-list(at)matronics.com =0ASent: Wednesd
ay, March 12, 2014 6:21 PM=0ASubject: Re: AeroElectric-List: Re: Timer circ
uit for led array=0A =0A=0A=0AThanks for the reply Jeff. Do you have any mo
re info on the automotive light delay relay? Dave Duperron -(davedup10@gm
ail.com.=0A=0A=0A=0AOn Wed, Mar 12, 2014 at 1:06 PM, Jeff Luckey wrote:=0A=0ATrue but ... =0A>=0A>that overlooks the convenience
of always-available cabin lighting without having the Master on.- =0A>
=0A>The post earlier today that referenced an existing automotive delay rel
ay looks like a great solution - cheap, designed for the purpose, plug-n-pl
ay, no re-inventing the wheel =0A>=0A>- what don't we like about that=0A>
=0A>=0A>=0A>-Jeff=0A>=0A>=0A>=0A>________________________________=0A> From:
Eric M. Jones =0A>To: aeroelectric-list(at)matronics.com
=0A>Sent: Wednesday, March 12, 2014 9:42 AM=0A>Subject: AeroElectric-List:
Re: Timer circuit for led array=0A> =0A>=0A>--> AeroElectric-List message
posted by: "Eric M. Jones" =0A>=0A>=0A>>- Timer circ
uit for led array--- Reply with quote=0A>> I'm looking for a timer to
shut off my cabin overhead utility light after about 10 minutes of operati
on. It's fed directly from the main battery buss and I would like to know t
hat if I forgot to turn it off the timer would do it for me before draining
the battery. Any ideas? David Duperron =0A>=0A>=0A>I learned to fly in Ces
snas, and as I recall leaving the beacon on was a certain way to avoid walk
ing away from the airplane with something still on.=0A>Perhaps the solution
to your problem is just to have the cabin light on the same bus as the bea
con.=0A>=0A>Adding an extra gizmo is not the best way to go.=0A>=0A>-------
-=0A>Eric M. Jones=0A>www.PerihelionDesign.com=0A>113 Brentwood Drive=0A>So
uthbridge, MA 01550=0A>(508) 764-2072=0A>emjones(at)charter.net=0A>=0A>=0A>
=0A>=0A>Read this topic online here:=0A>=0A>http://forums.matronics.comnbsp
; - - - - - - - - - -==0A>=0A>=0A>=0A>=0A>=0A>=0A>ist
" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List=0A
tp://forums.matronics.com=0A_blank">http://www.matronics.com/contribution
=====================
________________________________________________________________________________
From: | "Roger & Jean" <mrspudandcompany(at)verizon.net> |
Subject: | Re: Timer circuit for led array |
I haven't done a survey of the entire automotive world, but it seems
as if every car today has convenience lighting that turns on the
interior lights when the doors are unlocked and again when the car is
turned off. On my 2006 Toyota truck, they turn off when the doors are
locked, either with the switch on the door or with the remote.
Perhaps a You Pick car wrecker would be a good place to grab a circuit
whole for a relative cheap price.
I believe that you will find that most of the delays etc are
controlled through the car's computer and not with individual delay
circuits. I could be wrong, have been on occasion.
Roger
________________________________________________________________________________
From: | Craig Reding <clr(at)redingaviation.com> |
Subject: | spliting 2 wires at a dsub connector |
In the sprit of the comic books that Bob has put together which have
proven so valuable
I need to split a shielded wire into 2 pins on on a DSUB. I am sure that
what I did would be an acceptable approach but is there a better way?
this is a 2 conductor shielded wire. I have already added a pigtail
using a solder sleeve
thanks for the help
I striped off a 1/4 inch strip of insulation about 1 1/2 inches back
from the pin
I
following Bob=92s comic book on splicing wires i teased out a couple of
strands of the wire to be joined
Wrapped and soldered
added shrink wrap and crimped on the pin
________________________________________________________________________________
From: | "Jay Hyde" <jay(at)horriblehyde.com> |
Subject: | spliting 2 wires at a dsub connector |
That's a perfectly acceptable way to do it; I have used that method many
times without any problems.
Jay
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Craig
Reding
Sent: 13 March 2014 11:46 PM
Subject: AeroElectric-List: spliting 2 wires at a dsub connector
In the sprit of the comic books that Bob has put together which have proven
so valuable
I need to split a shielded wire into 2 pins on on a DSUB. I am sure that
what I did would be an acceptable approach but is there a better way?
this is a 2 conductor shielded wire. I have already added a pigtail using a
solder sleeve
thanks for the help
I striped off a 1/4 inch strip of insulation about 1 1/2 inches back from
the pin
I
following Bob's comic book on splicing wires i teased out a couple of
strands of the wire to be joined
Wrapped and soldered
added shrink wrap and crimped on the pin
________________________________________________________________________________
Subject: | Re: spliting 2 wires at a dsub connector |
From: | "Craig L. Reding" <clr(at)redingaviation.com> |
Jay
Thanks
> On Mar 15, 2014, at 4:47 AM, "Jay Hyde" wrote:
>
> That=99s a perfectly acceptable way to do it; I have used that metho
d many times without any problems.
>
> Jay
>
>
> From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelect
ric-list-server(at)matronics.com] On Behalf Of Craig Reding
> Sent: 13 March 2014 11:46 PM
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: spliting 2 wires at a dsub connector
>
>
> In the sprit of the comic books that Bob has put together which have prov
en so valuable
>
> I need to split a shielded wire into 2 pins on on a DSUB. I am sure that w
hat I did would be an acceptable approach but is there a better way?
> this is a 2 conductor shielded wire. I have already added a pigtail using a
solder sleeve
>
> thanks for the help
>
>
> I striped off a 1/4 inch strip of insulation about 1 1/2 inches back from t
he pin
> I
>
> following Bob=99s comic book on splicing wires i teased out a couple
of strands of the wire to be joined
>
>
> Wrapped and soldered
>
>
> added shrink wrap and crimped on the pin
>
>
>
________________________________________________________________________________
Subject: | Lithium batteries |
From: | Thomas E Blejwas <tomblejwas(at)yahoo.com> |
Bob,
Don't know which message it was in, but you mentioned that you we were working
on the last battery article for Kitplanes that would include lithium batteries.
I hope you will look at the EarthX batteries. They are now recommended on
the Viking website, so I've read their promotions. They actually have a section
on their website for experimental aircraft applications and they claim to deal
with charging/discharging issues that other lithium-iron-phosphate batteries
don't. I learned the hard way (had a meter lead plugged into the wrong socket)
that a brief inadvertent short of a Shorai battery will ruin it. Still haven't
heard of any explosive failures of batteries with this chemistry. I look
forward to your article.
Tom
Sent from my iPad
________________________________________________________________________________
Subject: | Re: spliting 2 wires at a dsub connector |
From: | "Eric M. Jones" <emjones(at)charter.net> |
For frequencies above about a MHz, this shouldn't be done, since the insulation
itself carries the signal. See attached.
By the way. I ran across a paper that recommended wire-nuts for connecting multiple
wires. Is there some reason not to do this?
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420383#420383
Attachments:
http://forums.matronics.com//files/dabbling_with_electricity_565.pdf
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Lithium batteries |
At 12:35 PM 3/15/2014, you wrote:
>
>
>Bob,
>
>Don't know which message it was in, but you mentioned that you we
>were working on the last battery article for Kitplanes that would
>include lithium batteries. I hope you will look at the EarthX
>batteries. They are now recommended on the Viking website, so I've
>read their promotions. They actually have a section on their
>website for experimental aircraft applications and they claim to
>deal with charging/discharging issues that other
>lithium-iron-phosphate batteries don't. I learned the hard way (had
>a meter lead plugged into the wrong socket) that a brief inadvertent
>short of a Shorai battery will ruin it. Still haven't heard of any
>explosive failures of batteries with this chemistry. I look forward
>to your article.
>
>Tom
Excellent input . . . thanks. I'll add them to the 'research'.
So far I've submitted three articles that speak to battery
selection and operations in general. The 4th is taking longer
than I thought . . . input from folks like yourself have
been helping me peel away the layers of the onion . . .
In the mean time, I'm submitting an article on mean time
between failure and how it has little or nothing to do
with system reliability. The article will be a prelude to
chapter 4 on lithium batteries where I'll remind readers
that irrespective of their battery choice, the electrically
dependent engine places new requirements on batteries.
Builders they need to look past the marketing rhetoric
for weight, cranking ability and any mumbling that
speaks to 'safety'. It's unfortunate that all the smoke
and fire (no pun intended) has pushed performance issues
to the back of the bus.
The article are to remind builders that they need
to purchase to design goals then test and maintain
to those goals.
A Kitplanes reader wrote Paul Dye to take issue
with a statement I made to the effect that I'd
never read of an accident where a backup system
would have made a difference. The "box" into which
the pilot driven was profound and in-escapable.
He related the fact that during a flight behind
his electrically dependent engine, a wire came
loose ad "took down the main bus". He said that
the presence of a back-up battery and a constellation
of switches to access it saved the day.
Through a couple of exchanges I discovered
that he had a hefty alternator and a 34 a.h.
battery . . . both of which became unavailable
to him thus forcing dependance upon a small
'backup' battery.
I suggested that while his particular system
WAS tolerant of that particular failure,
it was not very robust. I hoped to engage
him in conversation that would reduce his
reliance on a backup battery . . . but he was
rather unhappy about my assessment.
The point to be pondered is that no matter what
kind of battery you have on board, failure
tolerance has little to do with choice of parts,
their MTBF numbers or their marketing position
amongst the stars of products.
I'm getting no outpouring of data to support anyone's
marketing hype. E-mails are brushed aside with
an assertion of no comment, use on airplanes is
not supported, or simply ignored.
This has been an interesting exercise . . .
Bob . . .
________________________________________________________________________________
From: | "Roger & Jean" <mrspudandcompany(at)verizon.net> |
Subject: | Re: spliting 2 wires at a dsub connector |
>
> By the way. I ran across a paper that recommended wire-nuts for connecting
> multiple wires. Is there some reason not to do this?
The main reason that I could see is the
added bulk of the wire nuts might make
it difficult to impossible to add a cover
to the connector.
Roger
________________________________________________________________________________
From: | "B Tomm" <fvalarm(at)rapidnet.net> |
Subject: | Lithium batteries |
Bob,
I agree that EarthX, based on their forthcoming dialog, substance in their
answers, and willingness to support the amateur aircraft builders (even
encourage the use of their batteries in our aircraft, and why) has them on
my short list for when I finally need a battery for the RV7A. I strongly
suggest that you get in touch with them for your article. It will be very
easy to have an audience there.
Bevan
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Saturday, March 15, 2014 12:10 PM
Subject: Re: AeroElectric-List: Lithium batteries
-->
At 12:35 PM 3/15/2014, you wrote:
>
>
>Bob,
>
>Don't know which message it was in, but you mentioned that you we were
>working on the last battery article for Kitplanes that would include
>lithium batteries. I hope you will look at the EarthX batteries. They
>are now recommended on the Viking website, so I've read their
>promotions. They actually have a section on their website for
>experimental aircraft applications and they claim to deal with
>charging/discharging issues that other lithium-iron-phosphate batteries
>don't. I learned the hard way (had a meter lead plugged into the wrong
>socket) that a brief inadvertent short of a Shorai battery will ruin
>it. Still haven't heard of any explosive failures of batteries with
>this chemistry. I look forward to your article.
>
>Tom
Excellent input . . . thanks. I'll add them to the 'research'.
So far I've submitted three articles that speak to battery
selection and operations in general. The 4th is taking longer
than I thought . . . input from folks like yourself have
been helping me peel away the layers of the onion . . .
In the mean time, I'm submitting an article on mean time
between failure and how it has little or nothing to do
with system reliability. The article will be a prelude to
chapter 4 on lithium batteries where I'll remind readers
that irrespective of their battery choice, the electrically
dependent engine places new requirements on batteries.
Builders they need to look past the marketing rhetoric
for weight, cranking ability and any mumbling that
speaks to 'safety'. It's unfortunate that all the smoke
and fire (no pun intended) has pushed performance issues
to the back of the bus.
The article are to remind builders that they need
to purchase to design goals then test and maintain
to those goals.
A Kitplanes reader wrote Paul Dye to take issue
with a statement I made to the effect that I'd
never read of an accident where a backup system
would have made a difference. The "box" into which
the pilot driven was profound and in-escapable.
He related the fact that during a flight behind
his electrically dependent engine, a wire came
loose ad "took down the main bus". He said that
the presence of a back-up battery and a constellation
of switches to access it saved the day.
Through a couple of exchanges I discovered
that he had a hefty alternator and a 34 a.h.
battery . . . both of which became unavailable
to him thus forcing dependance upon a small
'backup' battery.
I suggested that while his particular system
WAS tolerant of that particular failure,
it was not very robust. I hoped to engage
him in conversation that would reduce his
reliance on a backup battery . . . but he was
rather unhappy about my assessment.
The point to be pondered is that no matter what
kind of battery you have on board, failure
tolerance has little to do with choice of parts,
their MTBF numbers or their marketing position
amongst the stars of products.
I'm getting no outpouring of data to support anyone's
marketing hype. E-mails are brushed aside with
an assertion of no comment, use on airplanes is
not supported, or simply ignored.
This has been an interesting exercise . . .
Bob . . .
________________________________________________________________________________
From: | "Michael McMahon" <mike(at)aeromotogroup.com> |
Subject: | Lithium batteries |
Mr. Brent Regan is apparently an expert on the use of Lithium batteries in
aircraft. I attempted to start a discussion on the LML list a few years ago
and he shut me down with his expertise. You may want to tap into his
exhaustive research on the subject:
http://lancair.net/lists/lml/Message/57030-P.txt
Michael
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of B Tomm
Sent: Saturday, March 15, 2014 6:43 PM
Subject: RE: AeroElectric-List: Lithium batteries
Bob,
I agree that EarthX, based on their forthcoming dialog, substance in their
answers, and willingness to support the amateur aircraft builders (even
encourage the use of their batteries in our aircraft, and why) has them on
my short list for when I finally need a battery for the RV7A. I strongly
suggest that you get in touch with them for your article. It will be very
easy to have an audience there.
Bevan
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Saturday, March 15, 2014 12:10 PM
Subject: Re: AeroElectric-List: Lithium batteries
-->
At 12:35 PM 3/15/2014, you wrote:
>
>
>Bob,
>
>Don't know which message it was in, but you mentioned that you we were
>working on the last battery article for Kitplanes that would include
>lithium batteries. I hope you will look at the EarthX batteries. They
>are now recommended on the Viking website, so I've read their
>promotions. They actually have a section on their website for
>experimental aircraft applications and they claim to deal with
>charging/discharging issues that other lithium-iron-phosphate batteries
>don't. I learned the hard way (had a meter lead plugged into the wrong
>socket) that a brief inadvertent short of a Shorai battery will ruin
>it. Still haven't heard of any explosive failures of batteries with
>this chemistry. I look forward to your article.
>
>Tom
Excellent input . . . thanks. I'll add them to the 'research'.
So far I've submitted three articles that speak to battery
selection and operations in general. The 4th is taking longer
than I thought . . . input from folks like yourself have
been helping me peel away the layers of the onion . . .
In the mean time, I'm submitting an article on mean time
between failure and how it has little or nothing to do
with system reliability. The article will be a prelude to
chapter 4 on lithium batteries where I'll remind readers
that irrespective of their battery choice, the electrically
dependent engine places new requirements on batteries.
Builders they need to look past the marketing rhetoric
for weight, cranking ability and any mumbling that
speaks to 'safety'. It's unfortunate that all the smoke
and fire (no pun intended) has pushed performance issues
to the back of the bus.
The article are to remind builders that they need
to purchase to design goals then test and maintain
to those goals.
A Kitplanes reader wrote Paul Dye to take issue
with a statement I made to the effect that I'd
never read of an accident where a backup system
would have made a difference. The "box" into which
the pilot driven was profound and in-escapable.
He related the fact that during a flight behind
his electrically dependent engine, a wire came
loose ad "took down the main bus". He said that
the presence of a back-up battery and a constellation
of switches to access it saved the day.
Through a couple of exchanges I discovered
that he had a hefty alternator and a 34 a.h.
battery . . . both of which became unavailable
to him thus forcing dependance upon a small
'backup' battery.
I suggested that while his particular system
WAS tolerant of that particular failure,
it was not very robust. I hoped to engage
him in conversation that would reduce his
reliance on a backup battery . . . but he was
rather unhappy about my assessment.
The point to be pondered is that no matter what
kind of battery you have on board, failure
tolerance has little to do with choice of parts,
their MTBF numbers or their marketing position
amongst the stars of products.
I'm getting no outpouring of data to support anyone's
marketing hype. E-mails are brushed aside with
an assertion of no comment, use on airplanes is
not supported, or simply ignored.
This has been an interesting exercise . . .
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: spliting 2 wires at a dsub connector |
At 01:27 PM 3/15/2014, you wrote:
>
>For frequencies above about a MHz, this shouldn't be done, since the
>insulation itself carries the signal. See attached.
I'd like to see the physics of this explained.
Yes, there is a skin-effect that pushes the current
flow to the surface of the conductor
http://tinyurl.com/n2h9ljy
. . . but carried on the insulation?
>By the way. I ran across a paper that recommended wire-nuts for
>connecting multiple wires. Is there some reason not to do this?
Wire nuts? Like this?
[]
Not recommended for aircraft
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | spliting 2 wires at a dsub connector |
>
>
>I need to split a shielded wire into 2 pins on on a DSUB. I am sure
>that what I did would be an acceptable approach but is there a better way?
>this is a 2 conductor shielded wire. I have already added a pigtail
>using a solder sleeve
>
>thanks for the help
Works good, lasts a long time . . .
Bob . . .
________________________________________________________________________________
Subject: | Re: spliting 2 wires at a dsub connector |
From: | Craig Reding <clr(at)redingaviation.com> |
Bob, Thank you very much for all of your lessons!
On Mar 15, 2014, at 10:59 PM, Robert L. Nuckolls, III
wrote:
>
>
>>
>>
>> I need to split a shielded wire into 2 pins on on a DSUB. I am sure that what
I did would be an acceptable approach but is there a better way?
>> this is a 2 conductor shielded wire. I have already added a pigtail using a
solder sleeve
>>
>> thanks for the help
>
>
>
>
>
> Works good, lasts a long time . . .
>
>
> Bob . . .
>
>
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Lithium batteries |
At 08:53 PM 3/15/2014, you wrote:
>
>
>Mr. Brent Regan is apparently an expert on the use of Lithium batteries in
>aircraft. I attempted to start a discussion on the LML list a few years ago
>and he shut me down with his expertise. You may want to tap into his
>exhaustive research on the subject:
>http://lancair.net/lists/lml/Message/57030-P.txt
Brent and I have crossed paths in the past but
I'm having trouble recalling now when, where and
in what context. I'll drop him a note and see
if he would be willing to collaborate on the
last installment of the series on batteries.
Thanks for the heads-up!
Bob . . .
________________________________________________________________________________
Subject: | New Over-Voltage Protection Architecture |
From: | "user9253" <fransew(at)gmail.com> |
Suppose that it is not desired that a crowbar type over-voltage protection device
to have the ability to disable the alternator on an aircraft with an electrically
dependent engine or electrically dependent instruments.
In the event that an externally regulated alternator puts out too high voltage,
is it feasible for the O.V. protection device to insert a series resistance
into the alternator field circuit instead of shorting it out? The amount of
resistance could be determined through trial and error to give 12-13 volts with
normal aircraft loads.
Or a resistor could be permanently installed in the alternator field circuit,
but normally shorted out by the O.V. protection device. In case of high voltage
or O.V. protection malfunction, the short across the resistor will be opened.
The alternator will then operate at reduced output determined by the load.
A low voltage warning will be indicated to the pilot who can increase or decrease
aircraft loads to fine tune the system voltage if desired. No circuit
breaker will pop nor will a fuse blow. The pilot or mechanic can troubleshoot
the low voltage condition after landing.
The advantage of this method of over-voltage protection is that the alternator
output will be reduced instead of completely disabled. Question is, is it practical
and feasible?
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420469#420469
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
I just became aware of EarthX batteries based on
comments here on the list. I visited their website
and studied a variety of assertions and comparisons
designed to promote sales. At first blush, these
folks are hanging their marketing hats on the same
philosophy as other suppliers of lithium technologies.
See attached document . . .
The DEARTH of good engineering data for these
products makes it difficult if not impossible to
craft a well considered integration of the current
COTS (commericial off the shelf) offerings onto
airplanes.
I had to delay submission of the last of four
Kitplanes articles for a month . . . not because
theres a paucity of choices . . . but because the
folks selling them can't define performance in
rational numbers. Still digging . . .
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
At 11:26 AM 3/17/2014, you wrote:
Suppose that it is not desired that a crowbar type over-voltage
protection device to have the ability to disable the alternator on an
aircraft with an electrically dependent engine or electrically
dependent instruments.
In the event that an externally regulated alternator puts out too
high voltage, is it feasible for the O.V. protection device to insert
a series resistance into the alternator field circuit instead of
shorting it out? The amount of resistance could be determined
through trial and error to give 12-13 volts with normal aircraft loads.
Why not just switch in a stand-by regulator?
http://tinyurl.com/npya5l7
. . .they're really cheap . . .
In the early days of the alternator fitted
C337 and Barons, controlled stand-by regulators
were part of the system . . .
Or a resistor could be permanently installed in the alternator field
circuit, but normally shorted out by the O.V. protection device. In
case of high voltage or O.V. protection malfunction, the short across
the resistor will be opened. The alternator will then operate at
reduced output determined by the load. A low voltage warning will be
indicated to the pilot who can increase or decrease aircraft loads to
fine tune the system voltage if desired. No circuit breaker will pop
nor will a fuse blow. The pilot or mechanic can troubleshoot the low
voltage condition after landing.
The advantage of this method of over-voltage protection is that the
alternator output will be reduced instead of completely
disabled. Question is, is it practical and feasible?
Pretty tough to sell . . . a voltage regulator
is an exceedingly agile device that will willingly
produce any field excitation level from near zero
to full bus voltage depending on loads and rpm.
You could conduct some experiments on your airplane
to deduce the size of such a resistor but . . . but
be sure to explore the "non nominal" conditions
to assess performance.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Skip,
Had a reader recommend EarthX lithium batteries for airplanes.
Seems they're courting Van's and some other suppliers of
kit aircraft and parts.
Downloaded a page of their marketing pitch. I commented on
it and published it back to my forum.
I'm going to contact EarthX for more information on ENERGY
numbers and a functional description of their 'battery
management system'.
See attached . . .
Bob . . .
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
From: | "user9253" <fransew(at)gmail.com> |
> Why not just switch in a stand-by regulator?
> http://tinyurl.com/npya5l7
> . . .they're really cheap . . .
>
Great idea. Thanks Bob
My RV-12 has a permanent magnet alternator. So I can not try out the series resistor
idea. I like to think about alternative ways of wiring an airplane. Most
of the time, the old way is the best way. :-)
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420475#420475
________________________________________________________________________________
Subject: | Re: EarthX lithium |
From: | Robert Borger <rlborger(at)mac.com> |
Bob N,
In your commentary on the FAQ. At the end there is a question about deeply discharging
the battery. Your comment is So if I go off and leave the master switch
ON, odds are that by the time I get back to fly again, my battery is trash?
I can answer that in one word - YES. Your battery is trash.
If this battery is like the one I purchased to test, it does not have a BMS which
auto-disconnects to protect cells from over-discharge.
I flew with this battery for several months and did some simple ground testing.
Tested things like - How long would it last running all the electrics (EIS,
EFIS, radio & transponder), how long just running the EIS, radio & transponder,
how long just running the EIS & radio and how long just running the EIS & transponder?
After each test I put the high-tech charger on and recharged with
the cell balance in effect. I didnt get to the last of the questions because
after the EIS, radio & transponder test I managed to put the charger on but left
the Master on as well. When I came back a couple days later to continue the
testing the battery was fully discharged and would not accept recharging. It
was trashed.
FYI, in testing the battery I found that it would run the whole electrical system
about 5 minutes. It would run the EIS, radio & transponder about 7 minutes.
Overall, I was not impressed with the LiFePo battery. It was extremely light and
it started my Rotax 914 quickly and easily. After starting the engine and
flying for a while, it would be properly and fully charged when back on the ground.
Unfortunately, from my limited testing, it didnt have any real legs to
run things on its own and it requires a lot of fancy, high-tech, gear to keep
it happy. And take great care not discharge it fully.
Just my 2 from my very limited experience.
Blue skies & tailwinds,
Bob Borger
Europa XS Tri, Rotax 914, Airmaster C/S Prop (50 hrs).
Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP
3705 Lynchburg Dr.
Corinth, TX 76208-5331
Cel: 817-992-1117
rlborger(at)mac.com
On Mar 17, 2014, at 11:40 AM, Robert L. Nuckolls, III
wrote:
I just became aware of EarthX batteries based on
comments here on the list. I visited their website
and studied a variety of assertions and comparisons
designed to promote sales. At first blush, these
folks are hanging their marketing hats on the same
philosophy as other suppliers of lithium technologies.
See attached document . . .
The DEARTH of good engineering data for these
products makes it difficult if not impossible to
craft a well considered integration of the current
COTS (commericial off the shelf) offerings onto
airplanes.
I had to delay submission of the last of four
Kitplanes articles for a month . . . not because
theres a paucity of choices . . . but because the
folks selling them can't define performance in
rational numbers. Still digging . . .
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: EarthX lithium |
At 12:46 PM 3/17/2014, you wrote:
Bob N,
In your commentary on the FAQ. At the end there
is a question about deeply discharging the
battery. Your comment is =93So if I go off and
leave the master switch ON, odds are that by the
time I get back to fly again, my battery is trash?
I can answer that in one word - YES. Your battery is trash.
If this battery is like the one I purchased to
test, it does not have a =93BMS=94 which
auto-disconnects to protect cells from over-discharge.
Which part number of battery did you test?
I flew with this battery for several months and
did some simple ground testing. Tested things
like - How long would it last running all the
electrics (EIS, EFIS, radio & transponder), how
long just running the EIS, radio & transponder,
how long just running the EIS & radio and how
long just running the EIS & transponder? After
each test I put the high-tech charger on and
recharged with the cell balance in effect. I
didn=92t get to the last of the questions because
after the EIS, radio & transponder test I managed
to put the charger on but left the Master on as
well. When I came back a couple days later to
continue the testing the battery was fully
discharged and would not accept recharging. It was trashed.
Good data point . . .
FYI, in testing the battery I found that it would
run the whole electrical system about 5
minutes. It would run the EIS, radio & transponder about 7 minutes.
Overall, I was not impressed with the LiFePo
battery. It was extremely light and it started
my Rotax 914 quickly and easily. After starting
the engine and flying for a while, it would be
properly and fully charged when back on the
ground. Unfortunately, from my limited testing,
it didn=92t have any real legs to run things on its
own and it requires a lot of fancy, high-tech,
gear to keep it happy. And take great care not discharge it fully.
Just my 2=A2 from my very limited experience.
From your limited observations, what would you estimate
the energy content to be for the model you tested? In
other words, what was the demand for the EIS, radio and
transponder? Apparently it would satisfactorily crank
an engine for some time.
I have emailed EarthX requesting the name and address
for an individual who can supply technical date in detail
sufficient to make good system integration choices.
Thanks for the data points!
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
>Great idea. Thanks Bob
>My RV-12 has a permanent magnet alternator. So I can not try out
>the series resistor idea. I like to think about alternative ways of
>wiring an airplane. Most of the time, the old way is the best way.
ALL ways are worthy of considered thought.
It's just as valuable to know what DOES work
as those things which are QUESTIONABLE.
I've often asked builders to get on the List
and tell us what was tried that didn't work . . .
like Bob's posting on EarthX . . .
It helps avoid discovering a bad idea over and
over again!
Bob . . .
________________________________________________________________________________
Subject: | Re: EarthX lithium |
From: | Robert Borger <rlborger(at)mac.com> |
Bob N,
LiFePo battery - AeroVoltz 8 Cell Lithium Battery.
http://aerovoltz.net/en/
The Sport EFIS consumes about 1 amp according to the documentation. I
don=92t have good numbers on the GRT EIS4000 but I would allow about 1
amp with all the sensors, back light, display, etc. I may be able to
get a better number next trip to the hanger. The radio and transponder
are MicroAir M760Q & T2000 SFL. =46rom the documentation, I=92d say
they each use about 250-300ma with the backlight on and not
transmitting.
The battery turned the 914 over very smartly. The engine is easy to
start in any case so it wasn=92t really working that hard. Three or 4
prop blades and it starts. That=92s 2 or 3 rotations of the engine.
Blue skies & tailwinds,
Bob Borger
Europa XS Tri, Rotax 914, Airmaster C/S Prop (50 hrs).
Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP
3705 Lynchburg Dr.
Corinth, TX 76208-5331
Cel: 817-992-1117
rlborger(at)mac.com
On Mar 17, 2014, at 1:17 PM, Robert L. Nuckolls, III
wrote:
At 12:46 PM 3/17/2014, you wrote:
Bob N,
In your commentary on the FAQ. At the end there is a question about
deeply discharging the battery. Your comment is =93So if I go off and
leave the master switch ON, odds are that by the time I get back to fly
again, my battery is trash?
I can answer that in one word - YES. Your battery is trash.
If this battery is like the one I purchased to test, it does not have a
=93BMS=94 which auto-disconnects to protect cells from over-discharge.
Which part number of battery did you test?
I flew with this battery for several months and did some simple ground
testing. Tested things like - How long would it last running all the
electrics (EIS, EFIS, radio & transponder), how long just running the
EIS, radio & transponder, how long just running the EIS & radio and how
long just running the EIS & transponder? After each test I put the
high-tech charger on and recharged with the cell balance in effect. I
didn=92t get to the last of the questions because after the EIS, radio &
transponder test I managed to put the charger on but left the Master on
as well. When I came back a couple days later to continue the testing
the battery was fully discharged and would not accept recharging. It
was trashed.
Good data point . . .
FYI, in testing the battery I found that it would run the whole
electrical system about 5 minutes. It would run the EIS, radio &
transponder about 7 minutes.
Overall, I was not impressed with the LiFePo battery. It was extremely
light and it started my Rotax 914 quickly and easily. After starting
the engine and flying for a while, it would be properly and fully
charged when back on the ground. Unfortunately, from my limited
testing, it didn=92t have any real legs to run things on its own and it
requires a lot of fancy, high-tech, gear to keep it happy. And take
great care not discharge it fully.
Just my 2=A2 from my very limited experience.
=46rom your limited observations, what would you estimate
the energy content to be for the model you tested? In
other words, what was the demand for the EIS, radio and
transponder? Apparently it would satisfactorily crank
an engine for some time.
I have emailed EarthX requesting the name and address
for an individual who can supply technical date in detail
sufficient to make good system integration choices.
Thanks for the data points!
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | RE: EarthX battery data |
At 01:17 PM 3/17/2014, you wrote:
>Dear Bob,
>
>I will forward this email to our engineering department so they can answer
>your questions on a more technical level. I did review your question about
>the conflicting statements and I am not sure I understand what is
>conflicting. But maybe this will clarify....you can put gasoline in a fire
>proof container, but if it is unfortunate enough to be involved in a fire,
>it can still catch fire. We have a BMS designed to protect from overcharge
>in the applications it is designed for, but if someone uses something that
>is in absolute conflict to how our product is designed, it could be a
>problem.
Understand. Where in your marketing literature are
there defined limits beyond which the BMS is unable
to prevent catastrophic failure?
In one document I am warned that inappropriate treatment
of EarthX batteries raises risks of "rupture and/or fire"
but there are no qualified or quantified limits to what
that treatment might be.
As a designer tasked with evaluating performance,
cost of ownership and risks associated with incorporation
of your offerings into my client's system.
When I compare this page from your website . . .
Emacs!
. . . with this data published elsewhere
Emacs!
I perceive a disconnect between EarthX claim for an 80%
lighter battery (1/5th the weight of a lead-acid).
Technical literature for comparative studies of lead-acid
vs. lithium suggest that weigh savings is on the
order of 66 percent weight reduction, not 80 percent.
Is EarthX claiming some breakthrough in performance
that offers a still lighter battery?
Further, the top bubble in the image from your website
speaks to a BMS in terms that seems to imply a bullet-proof
design . . . a feature that would be very attractive to
my client . . . as long as the limits to external
abuse are quantified and the behaviors of the BMS
are known.
>Not sure if that answers your question but I have forwarded this on.
>Sincerely,
>
>Kathy Nicoson
>Global Sales Director
>(970) 301-6064
>Fax: (970) 674-9544
>www. Earthxmotorsports.com
>sales(at)earthxmotorsports.com
I've worked with lead-acid, ni-cad and ni-mh batteries
for decades and there are few if any features of
performance that are not well known for these
chemistries. Much is known about lithium chemistries
but the numbers and bullet-points from literature
I've read so far on EarthX products leaves many
questions unanswered.
I'd really need to understand more about the physics
and design of your products before I can recommend
them into my client's application.
I appreciate your willingness to be of assistance.
Kindest regards,
Bob Nuckolls
AeroElectric Connection
Medicine Lodge, Kansas
>-----Original Message-----
>From: Robert L. Nuckolls, III [mailto:nuckolls.bob(at)aeroelectric.com]
>Sent: Monday, March 17, 2014 11:54 AM
>To: sales(at)earthxmotorsports.com
>Subject: EarthX battery data
>
>Good afternoon,
>
>By way of introduction I am a consulting engineer with a private practice in
>a variety of markets.
>
>I retired out of Beech Aircraft in 2007 after 45+ years experience in DC
>vehicular power systems, communications, failure analysis and system
>integration.
>
>I have a client who has asked me to explore your products suitability to
>task in a new program.
>
>I need to understand how your battery management system functions. Does it
>disconnect the battery from the system when in danger of over charging or
>excessive discharging? At what voltage levels to these features assert
>themselves?
>
>I am confused by what appears to be conflicting statements on your website.
>For example: On these two pages
>
>http://tinyurl.com/qex9gbg
>
>http://tinyurl.com/nxzf7r2
>
>I see statements that imply management of battery overcharge events by the
>BMS . . . but on the other page, we are cautioned about mis-applied chargers
>offer risks for battery rupture and/or fire.
>
>If an EarthX battery is inadvertently discharged too deeply, I presume the
>BMS will shut off current flow below some level . . . what are the limits
>for remaining in this discharged state in terms of recovering battery
>performance? Your website literature speaks to 4000 cycles . . . what depth
>of discharge is tolerated by EarthX batteries to meet the 4000 number? What
>capacity fraction used to benchmark end of life after 4000 cycles?
>
>I'm seeking engineering test data on energy content and internal impedance
>of the various EarthX products. In particular, a data sheet not unlike this
>document describing performance for a Panasonic SVLA battery . . .
>
>http://tinyurl.com/pjgzewx
>
>This format and detail of data will allow me to service my customer with a
>well considered decision on EarthX products for suitability to task.
>
>It would be very useful to have a contact name and email for an individual
>at EarthX who can supply needed data and carry on a dialog for any future
>questions.
>
>Kindest regards,
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: EarthX lithium |
At 02:01 PM 3/17/2014, you wrote:
Bob N,
LiFePo battery - AeroVoltz 8 Cell Lithium Battery. http://aerovoltz.net/en/
The Sport EFIS consumes about 1 amp according to the
documentation. I don't have good numbers on the GRT EIS4000 but I
would allow about 1 amp with all the sensors, back light, display,
etc. I may be able to get a better number next trip to the
hanger. The radio and transponder are MicroAir M760Q & T2000
SFL. From the documentation, I'd say they each use about 250-300ma
with the backlight on and not transmitting.
The battery turned the 914 over very smartly. The engine is easy to
start in any case so it wasn't really working that hard. Three or 4
prop blades and it starts. That's 2 or 3 rotations of the engine.
Okay, that's not an EarthX battery which
claims to have a battery management system
built in.
From the physical sizes of these batteries,
I suspect they are assembled from individual
cells not unlike the 26650 styles offered by
A123 and others.
http://tinyurl.com/ktyfbnp
These would be 'rated' at something on the
order of 2.3 to 2.5aH per cell. A 2-row,
8-cell assembly would offer a 12V battery
with a capacity on the order of 5aH. A number
which is inconsistent with your battery
only endurance experience.
Their 16-cell product would have a cell weight
of 75g x 16 or 1.2Kg. Their catalog weight for
the 16 cell product is 1.6Kg which leaves 0.4Kg
for enclosure . . . sounds about right. So
their 16-cell product would clock in with a 10aH
legacy rating and 1.2Kg x 125Wh/Kg or 150Wh
of total energy.
Given the relatively flat discharge curves of
lithium chemistries (low internal impedance) one
might estimate that 125Wh will be available at
a 10A discharge rate. So it seems that the 16-cell
device would run a 100W demand engine for 1.2 hours
when new and 1 hour at end of life.
Let's get some hard numbers on the current draw
for your experiments and see why you didn't get
better performance from your '5aH' product.
Aerovolts doesn't claim to offer an
internal BMS but they do offer the external
BMS charger with words like:
------------------------------------
The Aerovoltz Battery Management System Balance Charger is the only
charger on the market designed specifically to work with the
Aerovoltz battery. The primary advantage to the Aerovoltz BMS Blance
Charger is the balance charging function. The Balance mode balances
the voltage of each cell or cell pack while charging. By balance
charging your Aerovoltz Performance Battery you insure that the
battery is operating at its maximum power. Periodic balance charging
can also double the expected life of your battery. This charger is
not required to operate your Battery, but it is highly recommended.
The only charger made to work with the Battery Management System.
Plugs directly into the batteries BMS port.
Able to balance charge all the cells individually for max
power and durability.
Can double the expected life of the battery.
Has Charge, Fast Charge, Balance Charge, and Storage Charge
Functions.
Available in 120V (US) and 240V (EUR).
-------------------------------------
The problem I have with these special chargers is
rooted in the fact that when we put an airplane away,
the battery is generally topped off . . .
It's my understanding that these super-smart chargers
work their magic while recharging a partially to
completely depleted battery. How then would such a
charger benefit the OBAM aircraft owner/operator?
. . . and DOUBLE the life of the battery? THAT'S
a VERY LONG POLE in the tent for cost-of-ownership
for a battery that is already VERY expensive compared
to the device it purports to replace.
Aerovolts also claims:
-----------------------------------------
The 16 Cell has a massive 500PCA and 28 Pbeq AHs at only 3 lbs of
weight. The 16 Cell is a direct replacement of the Yuasa YTX30L-BS,
GYZ-20HL, and YTX24HL-BS.
-----------------------------------------
The Yuasa YTX30L is a 22 pound, SVLA battery that would
clock in at about 24aH . . . I submit that while the 16-cell
Aerovolts product may CRANK like the Yuasa battery, it is
NOT A DIRECT REPLACEMENT when it comes to keeping the
fires lit up front . . . in fact, it's probably less than
half the capacity of the Yuasa battery.
Emacs!
We'll keep asking questions . . .
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Lithium saga slogs ever onward . . . |
I downloaded the detail spec sheet for A123 26650
cells at . . .
http://tinyurl.com/n73f9gj
This cell and others like it seem to be the core
ingredient of choice for many of the off-the-shelf
battery products that are cropping up everywhere.
There's an interesting graphic in this data sheet . . .
Emacs!
Notice that the family of curves acknowledges the fact that this cell,
like all other sources of energy, has a source impedance. This is
illustrated by the fact that heavier loads produce initial plots on
the curve that are successively lower in voltage as the load current
rises. I.e., the higher the load, the higher will be I(squared)R
energy losses due to internal heating.
But then something magic happens. All three plots come together
at just under 2.5aH . . . gee . . . where did all those wasted
Watt-seconds go during discharge but magically showed up again
before the cell dropped below 2V?
Can't believe much that you read in the papers . . . gotta
be careful about data sheets too . . .
Bob . . .
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
From: | "Eric M. Jones" <emjones(at)charter.net> |
Joe,
Before you reinvent anything, let me show you my Proposed Perihelion Power Protector
(attached).
Repost from 20JUL07: (time flys...)
I talk to many builders who are particularly concerned about frying their expensive
avionics and glass panels. These parts are typically 1/3 of the airplane
cost.
Planning the wiring of a small aircraft involves installing systems to safeguard
the buses against failure of the alternator. Either an internally regulated
alternator or its more adaptable brother with an external regulator still has
the potential problem of a runaway condition, as well as a short circuit of the
main battery to alternator B-lead, and frequent load dump OV conditions.
A solution is herein proposed
Linear Technology has introduced a clever device, the LT4356-1 Overvoltage Protection
Regulator and Inrush Limiter to address all these worries. Not only thatthey
list Automotive/Avionic Surge Protection is one of its chief applications.
The LTC approach takes the high voltage from a load dump or failed alternator and
REGULATES it while the situation is being tamed. The IC package is 3mm X 4mm
and drives a big N-MOSFET that does the heavy work of regulating the voltage.
So what happens? Normally the alternator current is carried by the fully on N-MOSFET.
Assume the current is 50A, and the Rds(on) is 0.012 ohms. The dissipation
would be only 30W. This is easy to handle with a reasonable heat sink.
Assume the alternator and/or the regulator goes cuckoo. This could happen if the
alternator field winding shorts to the B-lead output or the sense lead in the
regulator opens, or other untoward goings-on. The alternator output goes into
an upward voltage spiral. This voltage is not unlimited, especially if there
is a load on it, but could be 80 VDC.
Now the LT4356-1 REGULATES the output via the big N-MOSFET on a heat sink. The
aircraft buses never sees more than 14.5 Volts (or whatever is desired). This
is true for the short time (500 mS) load dumps, and it will regulate a runaway
alternator for a time determined by whatever the N-MOSFET and heat sink can dissipate.
The LT4356-1 has a timer circuit to protect the N-MOSFET. If the time expires and
the stress continues, the fault warning signals an impending power-down and
the N-MOSFET shuts off the B-line.
Additionally, some models of the LT4356-1 have a spare amplifier/comparator that
can be used for any purpose (not shown here). It operates from 4 to 80 VDC,
and withstands 30V and up to 100V. A series low voltage P-MOSFET or a Schottky
diode can be added to protect against a shorted alternator that would draw reverse
current. The device has built-in protection again high current shorts of
the B-Line to the battery.
The drawing shows a basic form. A few additional parts are necessary. However,
consider the parts that WOULDNT be necessary:
The B-Line contactor,
The OV monitor,
The load dump preventer,
The B-Line fuse,
The alternator switch.
No crow bar or linear over voltage switch.
I dont have current plans to market this but will build one for myself.
Discussion is invited.
See attachment for a pdf version of this note with drawing.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420541#420541
Attachments:
http://forums.matronics.com//files/power_good_a1_176.pdf
http://forums.matronics.com//files/power_protector_schematic_383.pdf
http://forums.matronics.com//files/power_protector_revb_419.pdf
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
At 08:17 AM 3/18/2014, you wrote:
Joe,
Before you reinvent anything, let me show you my Proposed Perihelion
Power Protector (attached).
Repost from 20JUL07: (time flys...)
I talk to many builders who are particularly concerned about frying
their expensive avionics and glass panels. These parts are typically
1/3 of the airplane cost.
Planning the wiring of a small aircraft involves installing systems
to safeguard the buses against failure of the alternator. Either an
internally regulated alternator or its more adaptable brother with an
external regulator still has the potential problem of a runaway
condition, as well as a short circuit of the main battery to
alternator B-lead, and frequent load dump OV conditions.
"frequent"?
Linear Technology has introduced a clever device, the LT4356-1
Overvoltage Protection Regulator and Inrush Limiter to address all
these worries.
. . . but are they real worries . . .
We had an extended discussion on 'load dumps' here
on the List back about 2004. A sampling of the
work product during those conversations can be
accessed at . . .
http://tinyurl.com/ngu7ptq
Load dump speaks to the naturally occurring response
of the engine driven power source, its regulator
and perhaps the ship's battery to a sudden reduction of a
large load . . . like an air conditioner pump
motor, landing gear hydraulic pump motor, etc.
Another case supposes that a battery is not present
or becomes UNHOOKED during this heavy-load reduction.
Not only does the alternator/generator become suddenly
UNLOADED . . . the system may also be deprived of it's #1
load dump MITIGATOR . . . the battery.
This condition is addressed in DO-160/Mil-STD-704
as a recommendation designing a 14v product to
stand off 20V for 1S, 40V for 100mS. Double the
voltages for a 28V system. This is the time
it takes for an equally qualified OV management
system to corral the aberrant energy source and
bring the event to a graceful conclusion.
You will find the LT4356 cited in the constellation
of Google hits in the link cited above. This device
is but one of MANY approaches to achieving load-dump
robustness in aircraft. I've been testing to DO-160/
Mil-STD-704 for 40+ years and never found it necessary
to go to such extremes in parts count to protect the
input power port of my proposed appliance.
I'm not suggesting that the LT4356 does not perform
as advertised but I will suggest that it's an
inelegant solution to a problem that been the least
of our design challenges for decades.
I suggest that load-dump stresses that fall outside
the time honored design goals don't happen . . .
Recall how many times I've written about the paucity
of accidents having root cause in electrical system
issues. Of the few which did have electrically fertilized
roots, load-dump damage was not among them.
Further, how many installation manuals for your $high$ electro-
whizzies suggest any need to mitigate transient effects
above and beyond the DO-169 stresses to which they
have already qualified their product?
Can you imagine the cries out of the darkness and
renting of clothes should some big name like Garmin
hold forth with such a recommendation? Such an
assertion would mean one or both of two things (1)
DO-160 was found lacking or (2) Garmin was unable to
design to DO-160 design goals. You would be less
scorned if they predicted that the sun would rise
in the north tomorrow or that water molecule of H3O2
is predicted to freeze at 50C.
I did a pitch trim controller for the Lear 30/50
series airplanes that would stand off 80 volts for
tens if seconds . . . not milliseconds . . . it was no
big deal. My biggest challenge in that design was
to beat the parts count down in a worry-mitigation
watch-dog with about twice the parts count
of the controller. Over the years, failures in the
system were predominantly in the watch-dog
. . . not the controller.
The point being that one should be cautious when
taking on new worries about spikes, surges, bumps,
dumps, wiggles and jiggles on the bus that have
been pretty well understood for a long time. We
can look back at pyramid builders and marvel at
their cleverness and knowledge . . . but for them
it was all in a day's work.
http://tinyurl.com/n3swgjr
For those of us who made a vocation of simple, low cost,
robust designs in electrical systems . . . it's
all in a days work. The simple ideas upon which that
work is based is timeless, unchanging and indestructible.
Only the chefs and the recipes for success change . . .
hopefully for the better.
Bob . . .
________________________________________________________________________________
From: | D L Josephson <dlj04(at)josephson.com> |
Subject: | Re: Lithium batteries |
Perhaps those who have had LiFePO4 or other lithium batteries fail after
deep discharge would be willing to disassemble the various brands and
report what they find inside. This would possibly be more useful than
asking the sales people from the battery packagers for data they don't
wish to reveal.
I have been working with several groups who are researching electric
aircraft. The energy density and other characteristics of the available
cells are well known; at best a packaged battery is the sum of the cells
inside. If there is a BMS there are three simple questions to ask: is
there a low voltage disconnect during discharge, is there a high voltage
disconnect during charge, and how many cells are monitored together in
determining these voltages?
--
David Josephson
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | RE: EarthX battery data |
At 11:23 AM 3/18/2014, you wrote:
>Dear Bob,
>
>I do thank you for your input and responses and
>as this is a virgin market for us, based on the
>experimental aircraft market seeking us out, we
>are re-evaluating our labeling, our manual, and
>questions that need to be answered and really do appreciate your feedback.
>
>Our batteries were designed and marketed towards
>the power sport market and our website is geared
>towards customers, not engineers or OEM
>manufacturers, but we do have this data and will
>incorporate the needed information so our
>customers can make an informed decision.
Okay, I can help you with that effort.
I have written dozens of product performance
specifications for products that fly on
both commercial and military airplanes.
>
>
>As far as the 80% lighter=85=85.all lead acid
>manufacturers have different weights on the same
>lead acid replacement battery and then will also
>list different weights on the exact same lead
>acid battery out there. For example, the PC680
>is listed as 15.4 pounds on the Odyssey website,
>it is listed as 14.8 pounds on an Amazon listing
>and it is listed as 16 pounds on Battery Mart
>website. Another lead acid battery that is
>recommended to replace a PC680 is the Big Crank
>ETX30L which weighs 23 pounds. And of course,
>you can find different weighs listed for this
>battery as well but for simplicity, I will use the 23 pounds.
Yes, but you're not considering ALL of the
features for equivalency. I note that the
lithium chemistry entrepreneurs are fond
of the term "Lead-Acid Equivalency". It appears
that this term was invented out of whole
cloth to assert, "This lithium battery cranks
an engine as well as that lead-acid battery."
This is a useful term for folks interested only
with getting an engine started. I suggest to you
that airplanes are another matter entirely.
Airplanes have complex instrumentation, navigation
and communications requirements that need to be
powered when and if the alternator fails.
A smaller number of airplanes also feature electronically
managed engines with significant energy demands
on the order of 100 watts. If one expects to
sustain flight under battery-only conditions,
a common design goal is 1 hour of endurance,
2 hours would be MUCH better.
Hence, it is critical that your marketing literature
include data not unlike that which I cited for
the Panasonic lead-acid batteries. If you want
to drop into a battery box once occupied by a PC680,
consider the following data offered by Hawker/Enersys
concerning the performance of that battery . . .
http://tinyurl.com/ng9jhua
Emacs!
The PC680, when new, will carry a 130 watt demand
for one hour . . . only 45 minutes at end of battery
life.
Hawker/Enersys doesn't have a 22 pound battery
(10Kg) in that style, but if they did, it would
offer about 10/7 or about 1.4 times the capability
of the PC680.
What is the one-hour delivery capability of your
3.5 pound battery?
>
>The battery the we recommend to replace this
>battery is 3.5 pounds, for a 77-78% weight
>savings, depending on what weight you want to
>use compared to the Odyssey battery and 85%
>lighter than the Big Crank. We do list the
>actual weight in our battery spec=92s page on the
>website and it someone really needs to know the
>exact percent weight savings on the battery they
>are using for their application, they will have
>to do the math and get a real weight of the lead
>acid battery they are using compared to
>ours. Therefore, we do not feel there is a
>disconnect on our claim that we can be 80% lighter.
BUT . . . while your 3.5 pound offering will start
the engine as smartly as the 22 pound example, the
3.5 pound battery CANNOT support critical electronics
for the same time as the 22 pound battery.
For this reason, I counsel caution with respect to
that PbEq number. There's no engineering validation
for the term in an aviation market. Unfortunately,
most DIY airplane builders are NOT well versed in
the legacy terminology . . . much less new terms
created to promote the low internal impedance of
lithium cells.
Based on the above assertions, I suggest there is
a huge disconnect when you're talking to builders
and maintainers of personal aircraft. Assertion of
this equivalency at Cessna, Beech, Mooney or Piper
would probably get you more than raised eyebrows.
>
>And again, I have forwarded this to our
>engineering department and when they are able,
>they will get back to you or provide me with the answers to your questions.
>
>
>Sincerely,
>
>
>Kathy Nicoson
>Global Sales Director
>(970) 301-6064
>Fax: (970) 674-9544
>www. Earthxmotorsports.com
>sales(at)earthxmotorsports.com
Very well. Looking forward to it. Please convey
my willingness to be of assistance in crafting
competent and lucid literature for marketing
to aviation.
Kindest regards,
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | RE: EarthX battery data |
A heads-up to the List on my conversations with EarthX.
Of ALL the lithium wannabes I've approached for expanded
data on the operation and performance of their batteries,
EarthX has been the ONLY one to respond in any positive
and professional manner.
The e-mails I've forwarded to the List are conversations
with an individual in sales. I've received a data dump
from an applications person who promises to draw design
and performance talents into the conversation.
I'm not going to forward any more emails to the List
out of respect for their willingness to share what
may be considered proprietary data.
But I want to make the List aware of the fact that
EarthX seems interested in widening their customer
base on a foundation of well considered application
of their products.
I'm going to offer them assistance in crafting functional
specifications that speak purely to performance
in terms that would be appreciated by my colleagues
in TC aviation. At the same time, I will acquire
foundation for offering solid advice to the
OBAM aviation community as to suitability to
task for EarthX . . . or any other lithium
offering.
Watch this space.
Bob . . .
Bob . . .
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
From: | "user9253" <fransew(at)gmail.com> |
I like Eric's idea of opening the alternator output circuit in case of too high
voltage, rather than shorting out the field. One thing to consider is, what
happens if this device fails (even if unlikely)? Of course the same question
could be asked of the crowbar type of O.V. protection.
From a pilot's perspective, it is desired to have electrical power no matter
what goes wrong, provided that the cost and weight penalties are not too great.
Some builders install a second aircraft battery, which is a huge weight penalty.
How about combining Bob's suggestion of having a backup voltage regulator with
Eric's circuit (or modified AEC/9003)? In the event of over-voltage, automatically
turn off voltage regulator number one, and at the same time, turn on voltage
regulator number two, along with a warning light. Not only would the electrical
system be protected against over-voltage, but the alternator would keep
on supplying electrical power to the aircraft.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420616#420616
________________________________________________________________________________
Subject: | Re: RE: EarthX battery data |
From: | william mills <wtrooper(at)gmail.com> |
Bob -
I recognized EarthX's honesty and sincerity in response to your inquiries. Their
cooperative tone is indicative of a highly principled business ethic, sadly
lacking with some (most?) vendors.
EarthX should be recognized for this.
Thank you -
Bill
SF bay area
On Mar 19, 2014, at 6:23 AM, Robert L. Nuckolls, III wrote:
>
>
>
> A heads-up to the List on my conversations with EarthX.
>
> Of ALL the lithium wannabes I've approached for expanded
> data on the operation and performance of their batteries,
> EarthX has been the ONLY one to respond in any positive
> and professional manner.
>
> The e-mails I've forwarded to the List are conversations
> with an individual in sales. I've received a data dump
> from an applications person who promises to draw design
> and performance talents into the conversation.
>
> I'm not going to forward any more emails to the List
> out of respect for their willingness to share what
> may be considered proprietary data.
>
> But I want to make the List aware of the fact that
> EarthX seems interested in widening their customer
> base on a foundation of well considered application
> of their products.
>
> I'm going to offer them assistance in crafting functional
> specifications that speak purely to performance
> in terms that would be appreciated by my colleagues
> in TC aviation. At the same time, I will acquire
> foundation for offering solid advice to the
> OBAM aviation community as to suitability to
> task for EarthX . . . or any other lithium
> offering.
>
> Watch this space.
>
> Bob . . .
>
>
> Bob . . .
>
>
>
>
>
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Subject: | Re: New Over-Voltage Protection Architecture |
You might be approaching a situation where "the cure is worse than the dise
ase".- You have to be careful when stacking widgets on top of gizmos in p
ursuit of greater reliability.- That approach quite often leads to greate
r complexity & lower reliability.=0A=0A=0A-Jeff=0A=0A=0A___________________
_____________=0A From: user9253 <fransew(at)gmail.com>=0ATo: aeroelectric-list
@matronics.com =0ASent: Wednesday, March 19, 2014 8:01 AM=0ASubject: AeroEl
ectric-List: Re: New Over-Voltage Protection Architecture=0A =0A=0A--> Aero
Electric-List message posted by: "user9253" =0A=0AI like
Eric's idea of opening the alternator output circuit in case of too high v
oltage, rather than shorting out the field.- One thing to consider is, wh
at happens if this device fails (even if unlikely)?- Of course the same q
uestion could be asked of the crowbar type of O.V. protection.=0A- From a
pilot's perspective, it is desired to have electrical power no matter what
goes wrong, provided that the cost and weight penalties are not too great.
- Some builders install a second aircraft battery, which is a huge weight
penalty.=0A- How about combining Bob's suggestion of having a backup vol
tage regulator with Eric's circuit (or modified AEC/9003)?- In the event
of over-voltage, automatically turn off voltage regulator number one, and a
t the same time, turn on voltage regulator number two, along with a warning
light.- Not only would the electrical system be protected against over-v
oltage, but the alternator would keep on supplying electrical power to the
aircraft.=0AJoe=0A=0A--------=0AJoe Gores=0A=0A=0A=0A=0ARead this topic onl
ine here:=0A=0Ahttp://forums.matronics.com/viewtopic.php?p=420616#420616
=
________________________________________________________________________________
From: | "Roger & Jean" <mrspudandcompany(at)verizon.net> |
Subject: | Re: New Over-Voltage Protection Architecture |
> How about combining Bob's suggestion of having a backup voltage regulator
> with Eric's circuit (or modified AEC/9003)? In the event of over-voltage,
> automatically turn off voltage regulator number one, and at the same time,
> turn on voltage regulator number two, along with a warning light. Not
> only would the electrical system be protected against over-voltage, but
> the alternator would keep on supplying electrical power to the aircraft.
That's all well and good if the failure is the regulator!
My experience, however has been that the alternator
is several times more prone to failure than the regulator,
and this senerio will not fix a defective alternator!
Roger
________________________________________________________________________________
From: | Stuart Hutchison <stuart(at)stuarthutchison.com.au> |
G'day Bob N.
Your comments in the PDF file about battery Ah rating under different
operating conditions reminded me of an interesting annecdote.
About 10 years ago, Energiser began marketing a series of cheap (approx $20)
AA battery powered chargers for cell phones. They are a simple plastic case
(inc circuit) for two primary AA cells, plus a short adaptor cord option for
the various cell phone models. Turns out they come fitted with lithium
cells for good reason.
>From spec data sheets at the time, the rating for a standard Energiser
alkaline AA cell was typically around 2700 mAh. The lithium cells were
about 3200 mAh, yet manufacturers quoted 5 to 7 times the endurance for
lithium cells in high power devices. This seemed counter-intuitive given a
similar mAh rating.
In practice, the lithium cells can deliver higher current without the
internal resistance soaring through the roof, so most of their energy is
delivered to the load rather than wasted as heat. It was easily proven by
replacing the AA lithium cells with alkaline cells. The alkaline cells
became too hot to touch and delivered about half a cell phone charge, while
the lithium cells delivered about 2.5 full charges. Conversely, using
lithium cells in a low power device such as a wall clock would offer a very
poor return on investment, given the lithium AA cells cost about 4 times the
price.
Cheers, Stu
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Tuesday, March 18, 2014 3:41 AM
Subject: AeroElectric-List: EarthX lithium
I just became aware of EarthX batteries based on comments here on the list.
I visited their website and studied a variety of assertions and comparisons
designed to promote sales. At first blush, these folks are hanging their
marketing hats on the same philosophy as other suppliers of lithium
technologies.
See attached document . . .
The DEARTH of good engineering data for these products makes it difficult if
not impossible to craft a well considered integration of the current COTS
(commericial off the shelf) offerings onto airplanes.
I had to delay submission of the last of four Kitplanes articles for a month
. . . not because theres a paucity of choices . . . but because the folks
selling them can't define performance in rational numbers. Still digging . .
.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
> . . . using lithium cells in a low power device such as a wall
> clock would offer a very
>poor return on investment, given the lithium AA cells cost about 4 times the
>price.
Yeah, your talking about these critters . . .
Emacs!
They're in the Size 91 package (AA) but offer a lithium-Iron
couple that's in the same ballpark as the carbon-zinc and
zinc-manganese flashlight cells (1.5 volts).
If you compare E91 alkaline cell data
Vhttp://tinyurl.com/nt2x8hd
with the L91 lithium-iron data
http://tinyurl.com/otkeubs
We see that both products are in the same ballpark
for contained energy but the L91 cell internal
resistance is about 1/2 that of the E91. So not
only do you get slightly more total energy, your
access to that energy at high discharge rates suffers
about 1/2 the losses in heat.
This 'lithium' product is a different animal from
the devices we're pondering as replacement for
engine-cranking/standby service. The boss-hogg
lithium cells are 3.3V couples and generally
much lower resistance still . . .
It's unfortunate that characteristic performance
of two cells are not presented in the same pews . . .
suffice it to say that the approx 1/2 internal
resistance will toss off less energy under high
demand loads.
On the Nickle-Metal Hydride side of the house
one may acquire 1.2V chemistry with very attractive
internal impedances . . .
http://tinyurl.com/nj5xx85
At 1.2V vs. 1.5 volts the contained energy
in watt-seconds suffers slightly but they'll
readily deliver their contents at high rates.
Down-side is that the self-discharge characteristics
of Ni-Mh compared to the Lithium-Iron or Zinc-Manganese
cells is pretty sad. Up-side is that you can readily
re-use these cells many times over and their
acquisition costs are nominal.
http://tinyurl.com/nklo97k
Your right, lithium-iron AA cells poor value compared
to other choices . . . unless your design goals
absolutely demand high rate discharge support
AND long shelf life.
Its all in the design goals . . .
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
At 10:58 AM 3/19/2014, you wrote:
>You might be approaching a situation where "the cure is worse than
>the disease". You have to be careful when stacking widgets on top
>of gizmos in pursuit of greater reliability. That approach quite
>often leads to greater complexity & lower reliability.
Good put.
What is the line of thought that drives the
notion that simple removal of field voltage from
a runaway system is inconsistent with our
assessment of risk?
I'll have to ask around . . . I've been disconnected
from the field service loop in regulators for some
years . . . but I don't recall any controllers ever coming
back to B&C where a regulator fallen from grace
was blessed with salvation by the ov protection
system.
I'm not suggesting that such failure rates are zero but
they ARE quite small. Further the prudent response
to a competent FMEA dictates that we include such
protection in spite of those low failure rates.
It's been a long time since I've observed a car
approaching me at night with lights that were too
blue/bright demonstrating the fact that a poor
battery was doing its best to stand off a
runaway alternator.
I'm also reading anecdotal bits about stock,
automotive alternators being incorporated onto
aircraft sans ov protection. It MIGHT be that
contemporary regulators have achieved 10 to the
minus 9 or better failure rates that suggest
the ov protection is no longer necessary/useful.
If anyone runs across such an incident, I'd like
to hear about it.
Bob . . .
________________________________________________________________________________
Subject: | Re: EarthX Batteries |
From: | speedy11(at)aol.com |
I concur with Bob's comments. My dealings with the folks at EarthX has be
en professional and forthcoming.
It appears they are pushing hard to become the market leaders and their bat
tery monitoring system may be just the thing to get them there.
I have decided to distribute their batteries at my FBO operation and I will
be ordering two batteries soon to replace the PC680s in my RV-8A (Reno Rac
e 84). I will follow up with non-technical, but nonetheless interesting da
ta points on my experience using the lithium batteries.
Stan Sutterfield
Spruce Creek FBO
Daytona Beach
A heads-up to the List on my conversations with EarthX.
Of ALL the lithium wannabes I've approached for expanded
data on the operation and performance of their batteries,
EarthX has been the ONLY one to respond in any positive
and professional manner.
The e-mails I've forwarded to the List are conversations
with an individual in sales. I've received a data dump
from an applications person who promises to draw design
and performance talents into the conversation.
I'm not going to forward any more emails to the List
out of respect for their willingness to share what
may be considered proprietary data.
But I want to make the List aware of the fact that
EarthX seems interested in widening their customer
base on a foundation of well considered application
of their products.
I'm going to offer them assistance in crafting functional
specifications that speak purely to performance
in terms that would be appreciated by my colleagues
in TC aviation. At the same time, I will acquire
foundation for offering solid advice to the
OBAM aviation community as to suitability to
task for EarthX . . . or any other lithium
offering.
Watch this space.
Bob . . .
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
From: | "user9253" <fransew(at)gmail.com> |
A voltage regulator is not likely to fail unless overheated. An over-voltage protection
device is less likely to fail because it is usually not subject to excessive
heat. What is more likely to fail is an electrical connection or switch
somewhere between the main bus and the voltage regulator. Good workmanship,
strain relieved terminals, and a dab of grease to prevent corrosion, will all
help. Even if properly installed, switches and connections can corrode over
time. These problems are unlikely to be detected during annual inspections.
Many modern avionics can operate on voltages between 10 and 30, and can withstand
minor voltage excursions. Over-voltage protection is like buying insurance.
Is it worth the premium?
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420718#420718
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
From: | "Eric M. Jones" <emjones(at)charter.net> |
I learned to fly in a club with five Cessnas, and the only alternator failure I
was personally involved with was an alternator bracket that broke from fatigue.
(There was one "failure to charge" whose cause I never learned.)
If you look at all the ways an aircraft can fail, I think alternator failures are
low on the list. I have not heard of a NEW (not rebuilt) Nippondenso alternator
that failed at all, save overheating, drowning, old age, etc. This might
be true of other manufacturers as well. Any reports to the contrary?
Rather than trying to protect the electrical system from a failed alternator, perhaps
some effort in determining when an alternator should be replaced would
be a good approach. 1000 hours, engine TBO?
Most electrical parts benefit from not being driven too hard, and being kept cool.
If this is done, count me as unconvinced that OVP is necessary with an internally-regulated
modern alternator.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420721#420721
________________________________________________________________________________
From: | Charlie England <ceengland7(at)gmail.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
On 3/20/2014 2:11 PM, Robert L. Nuckolls, III wrote:
>
>
> At 10:58 AM 3/19/2014, you wrote:
>> You might be approaching a situation where "the cure is worse than
>> the disease". You have to be careful when stacking widgets on top of
>> gizmos in pursuit of greater reliability. That approach quite often
>> leads to greater complexity & lower reliability.
>
> Good put.
>
> What is the line of thought that drives the
> notion that simple removal of field voltage from
> a runaway system is inconsistent with our
> assessment of risk?
>
> I'll have to ask around . . . I've been disconnected
> from the field service loop in regulators for some
> years . . . but I don't recall any controllers ever coming
> back to B&C where a regulator fallen from grace
> was blessed with salvation by the ov protection
> system.
>
> I'm not suggesting that such failure rates are zero but
> they ARE quite small. Further the prudent response
> to a competent FMEA dictates that we include such
> protection in spite of those low failure rates.
>
> It's been a long time since I've observed a car
> approaching me at night with lights that were too
> blue/bright demonstrating the fact that a poor
> battery was doing its best to stand off a
> runaway alternator.
>
> I'm also reading anecdotal bits about stock,
> automotive alternators being incorporated onto
> aircraft sans ov protection. It MIGHT be that
> contemporary regulators have achieved 10 to the
> minus 9 or better failure rates that suggest
> the ov protection is no longer necessary/useful.
>
> If anyone runs across such an incident, I'd like
> to hear about it.
>
>
> Bob . . .
Are you asking for incidents of *non* failures with internally regulated
alternators & no protection? I've been running a Denso on an RV-4 Lyc
O320 for about a decade. Not a lot of hours (probably around 400), but
no issues with OV. This is a very simple VFR a/c that only recently
acquired a transponder, so my financial and safety risks have been
pretty low. I'll probably incorporate some type of protection on the -7
I'm building, just because I'll have more money tied up in the panel.
Charlie
________________________________________________________________________________
From: | David Josephson <dlj04(at)josephson.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
> What is the line of thought that drives the
> notion that simple removal of field voltage from
> a runaway system is inconsistent with our
> assessment of risk?
Only that removal of field voltage is impossible with a permanent magnet
alternator and inconvenient with an internally regulated one.
________________________________________________________________________________
From: | D L Josephson <dlj04(at)josephson.com> |
Subject: | Re: Earth-X lithium |
Just as lead-acid electrochemistry is fairly well understood, lithium
cell vendors and types are well known. Every maker of small "aviation"
lithium batteries uses the same LiFePO4 18650 cell type as far as I
know, which is also the same as Tesla uses in their car battery packs,
and the same chemistry used in most smartphones today. There are various
quality levels available, with the leader seeming to be the Panasonic
NCR18650A, which is honestly rated at 2.9 amp-hours at 3.2 volts (more
than 2.9 can be claimed by assuming a lower cutout voltage, which
requires more precise low voltage disconnect to avoid damage.) Packs are
made of strings of 4 cells in series, which is why you see 8-, 12-, 16
etc. cell "batteries."
At last year's CAFE Electric Aircraft Symposium, Eric Darcy from NASA,
who is responsible for designing the lithium batteries for the Space
Station, gave some pointers on testing these ubiquitous cells for
quality (you measure open circuit voltage over a few weeks -- cells that
droop faster than the norm are suspect) and the measures that need to be
taken to assure safe charging and low voltage disconnect. We learned
that quality was primarily related to clean shearing and even winding of
the internal foil materials, with failures mostly due to minute stray
particles of the sheared material causing leakage, or misalignment of
the wound structure allowing the edges to touch.
Ideally each cell is charged separately. Next best is to charge each
pack of 4 cells separately. The trick comes in designing a battery
management system inside the box that manages charge current for
multiple packs and at the very least alerts you if something is wrong. A
battery company that will actually explain how they are doing these
things, and takes the time to explain why a watt-hour of lithium cells
might be more useful than the same watt-hour of lead acid, would be
worth paying attention to.
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Subject: | Re: New Over-Voltage Protection Architecture |
=0A=0A=0A=0A________________________________=0A From: David Josephson <dlj0
4(at)josephson.com>=0ATo: aeroelectric-list(at)matronics.com =0ASent: Friday, Mar
ch 21, 2014 9:21 AM=0ASubject: AeroElectric-List: Re: New Over-Voltage Prot
Josephson =0A=0A=0A=0A>- - - What is the line
of thought that drives the=0A>- - - notion that simple removal of fi
eld voltage from=0A>- - - a runaway system is inconsistent with our
=0A>- - - assessment of risk?=0A=0AOnly that removal of field voltag
e is impossible with a permanent magnet =0Aalternator and inconvenient with
an internally regulated one.=0A=0ADavid,=0A=0AI've never had occasion to f
iddle with a PM alternator. =0A=0AI've always thought of a run-away conditi
on as=0Aa regulator failure where it is no longer "regulating" =0Aand apply
ing full field current.=0A=0ACan a PM alternator "run-away"?=0A=0A-Jeff=0A
=========================0A
===================
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
At 11:21 AM 3/21/2014, you wrote:
>
>
>> What is the line of thought that drives the
>> notion that simple removal of field voltage from
>> a runaway system is inconsistent with our
>> assessment of risk?
>
>Only that removal of field voltage is impossible with a permanent
>magnet alternator and inconvenient with an internally regulated one.
That's why all the z-figures that incorporate
pm alternators use a disconnect relay paired with
an ov sensor to effect a disconnect . . .
This unique characteristic of the PM alternator
is what suggested that they be called a 'dynamo'
to separate them out from the herd of engine driven
power sources. B-lead disconnect has also been
suggested in Figure z-24 of the 'Connection's collection
of architectures.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
At 08:23 AM 3/21/2014, you wrote:
A voltage regulator is not likely to fail unless overheated. An
over-voltage protection device is less likely to fail because it is
usually not subject to excessive heat. What is more likely to fail
is an electrical connection or switch somewhere between the main bus
and the voltage regulator. Good workmanship, strain relieved
terminals, and a dab of grease to prevent corrosion, will all
help. Even if properly installed, switches and connections can
corrode over time. These problems are unlikely to be detected during
annual inspections.
There are two approaches to system reliability analysis.
One approach assumes NO backup . . . either because such
features are too costly/bulky/heavy/etc or simply not
possible.
If any of these features are critical to comfortable
termination of flight, they get designed and tested
for very high probability of meeting a 'design service life'
that is generally some multiple of 'practical service life'.
For example, flown long enough, the wings on EVERY aluminum
airplane are going to break off. This is because aluminum,
unlike steel, has a stress-to-cycles plot that never goes
'flat'. If you stress and relieve a steel part to maxiumum
ever expected loads 10,000,000 times without breaking
it, the part is considered 'golden' and will last forever.
Aluminum has no such feature . . . it eventually fails at
any stress loading . . . the cycles may be very high but
there is no flat spot on the s/n curve to failure. Hence
you see a totally different approach for the design setting
service limits for qualification of structural parts on
airplanes. Approaches that have continuously evolved over
the years particularly in response to incidents like this . . .
http://www.aloha.net/~icarus/243a.jpg
Emacs!
An alternative technique for making design decisions
can be adopted for items that are not immediately
catastrophic. The generally categorized by criticality
level not unlike software under DO-178 . . .
(a) Catastrophic - Failure may cause multiple fatalities, usually
with loss of the airplane.
(b) Hazardous - Failure has a large negative impact on safety or
performance, or reduces the ability of the crew to operate the
aircraft due to physical distress or a higher workload, or causes
serious or fatal injuries among the passengers.
(c) Major - Failure significantly reduces the safety margin or
significantly increases crew workload. May result in passenger
discomfort (or even minor injuries).
(d) Minor - Failure slightly reduces the safety margin or slightly
increases crew workload. Examples might include causing passenger
inconvenience or a routine flight plan change.
(e) No Effect - Failure has no impact on safety, aircraft operation,
or crew workload.
For OBAM aircraft, we're free to tighten up our spectrum
of criticality level. Depending on the design of our
plan-B, we can generally drop to 3 categories . . .
(a) Engine stops and we're going to descend . . . NOW
(b) Some appliance goes dark and finding our way to
comfortable landing . . . preferably at airport
of intended destination . . . is at risk.
(c) Some appliance goes dark but while convenient,
is not critical to continued flight, navigation,
approach to landing and parking the airplane.
These three categories focus on system components
like fuel pumps, ECM, nav receivers, orientation
aids, panel lighting, electronic ignition, comm,
and perhaps xponder. The builder/pilot has to
decide what order of important fits their particular
project and the environment in which they intend to fly.
Then an architecture and hardware compliment needs
to be crafted such that no single failure takes down
more than one accessory and all really useful or
critical accessories have a plan-B.
The elegant solution minimizes weight, cost, volume,
parts-count and pilot work loads.
It takes an appreciation of the thoughts outlined
above to understand the rationale for careful
consideration before ov protection is no longer
in your plans.
Recall that MTBF numbers say NOTHING about the
behavior of any single part. If one strives for
predictable behavior, then you venture into the
world of 'established reliability' accessories
where a great deal of money has been spend to design,
test, manufacture and perhaps even screen finished
goods to weed out infant mortality . . .
The easiest way to deal with SYSTEM reliability
with internally regulated alternators is to ASSUME
it will fail and install a plan-b . . . as long as
that addition is not a significant cost/weight
adder. OV protection adds little overhead. Second
alternators add some weight and up-front costs
but minimizes cost of ownership. Second batteries
are probably cheaper up front but add more weight
and perpetual cost of ownership burdens for
preventative maintenance and r/r costs common
to an expendable commodity.
Don't forget one super-significant feature of
the engine driven power source: It's an inexhaustible
source of energy . . . at potentially high voltages
(100+ volts). The alternator is unique in this
regard. The battery can deliver a lot of current
but its energy reservoir is limited. The alternator
is current limited but for all practical purposes,
it's output voltage and total energy is not limited.
These features are foundations on which you build
your personal failure mode effects analysis.
An analysis that could not care less about anecdotal
reliability narratives and builds a foundation of
system reliability on logic assembly of simple-ideas
irrespective of any perceptions of probability.
Many modern avionics can operate on voltages between 10 and 30, and
can withstand minor voltage excursions. Over-voltage protection is
like buying insurance. Is it worth the premium?
OV protection is not about minor excursions. It's about
unleashing the flame thrower first against your battery
(by the way, if it's a tiny lithium super-cranker,
it will toss in the towel much faster than your 18 or
24Ah SVLA brick) and then upon system accessories.
Just a few steps from where I sit right now is a lab
where these features and effects have been studied
for years. It's not a concept to be dismissed lightly.
A runaway alternator is the acme of electrical disasters
on about any DC power system. If you're willing to buy
into the anecdotal 'never heard of it happening' . . . then
ask the supplier of your alternator/regulator combination
if he'll guarantee replacement of electro-whizzies
on your panel if his gizmo fails?
This is why we elected to bring the B&c alternator
controllers to market as a TRIO of accessories that
offered a very favorable FMEA. The thought was that
if the customer wanted to go a different route, they're
certainly free to do so . . . but not with our product.
Proceed with both caution and confidence borne out of
lessons learned . . .
Bob . . .
________________________________________________________________________________
Subject: | Std density D sub pins. |
From: | Tim Andres <tim2542(at)sbcglobal.net> |
Bob, what is the current rating on the Std density D sub pins? This is re: your
avionics ground bus and the 18 gauge com wires going into it. I have the oversize
pins that accept 18 awg, but I'm thinking the ~8 amps intermittent load needs
to be divided over two pins.
Thanks
Tim
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Std density D sub pins. |
At 09:10 AM 3/22/2014, you wrote:
>
>Bob, what is the current rating on the Std density D sub pins? This
>is re: your avionics ground bus and the 18 gauge com wires going
>into it. I have the oversize pins that accept 18 awg, but I'm
>thinking the ~8 amps intermittent load needs to be divided over two pins.
>Thanks
>Tim
Splitting it onto 2 pins with 6", 22AWG
ballast pigtails is never wrong . . .
but the super-pin might be okay.
What accessory are you talking about?
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Lamar Super-Switch solid state contactor |
At 11:15 AM 3/22/2014, you wrote:
>Bob,
>I have been told you have a solid state master relay that will not
>get hot like my one amp current relay. Could you please tell me the
>part number for the relay. Your book has been a real inspiration.
Thank you.
Lamar used to manufacture one, Aircraft Spruce
used to sell them. I don't find them
on either website. I think the product
has been pulled. At one time the factory
had me on a 'list ' to receive an engineering
sample for evaluation . . . but I've never
seen one in the 'flesh' . . .
What's your application? What are your design
goals? Is it just the heat that bothers you?
Yes, they are hot to touch but that does not
automatically translate into an evil property.
The light bulb gets hot too but delivers the
advertised performance.
Bob . . .
________________________________________________________________________________
From: | Tim Andres <tim2542(at)sbcglobal.net> |
Subject: | Re: Std density D sub pins. |
This is for a- GTN 650 GPS/NAV/COMM. All the grounds out of that box.=0AT
im=0A=0A=0A=0A=0A________________________________=0A From: "Robert L. Nucko
lls, III" =0ATo: aeroelectric-list@matronics
.com =0ASent: Saturday, March 22, 2014 9:38 AM=0ASubject: Re: AeroElectric-
List: Std density D sub pins.=0A =0A=0A--> AeroElectric-List message posted
by: "Robert L. Nuckolls, III" =0A=0AAt 09:1
Andres =0A> =0A> Bob, what is the current rating on
the Std density D sub pins? This is re: your avionics ground bus and the 1
8 gauge com wires going into it. I have the oversize pins that accept 18 aw
g, but I'm thinking the ~8 amps intermittent load needs to be divided over
two pins.=0A> Thanks=0A> Tim=0A=0A=0A- Splitting it onto 2 pins with 6",
22AWG=0A- ballast pigtails is never wrong . . .=0A- but the super-pin m
ight be okay.=0A=0A- What accessory are you talking about?=0A=0A=0A- Bo
======================
________________________________________________________________________________
Subject: | Re: Std density D sub pins. |
From: | Bill Allen <billallensworld(at)gmail.com> |
Hi Guys,
Good question Tim <> I'm looking at something similar right now
Bob; I'm not sure I understand correctly what << with 6", 22AWG
ballast pigtails >> means? Can you clarify?
regards,
Bill Allen
On 22 March 2014 17:31, Tim Andres wrote:
> This is for a GTN 650 GPS/NAV/COMM. All the grounds out of that box.
> Tim
>
>
> ------------------------------
> *From:* "Robert L. Nuckolls, III"
> *To:* aeroelectric-list(at)matronics.com
> *Sent:* Saturday, March 22, 2014 9:38 AM
> *Subject:* Re: AeroElectric-List: Std density D sub pins.
>
> nuckolls.bob(at)aeroelectric.com>
>
> At 09:10 AM 3/22/2014, you wrote:
> tim2542(at)sbcglobal.net>
> >
> > Bob, what is the current rating on the Std density D sub pins? This is
> re: your avionics ground bus and the 18 gauge com wires going into it. I
> have the oversize pins that accept 18 awg, but I'm thinking the ~8 amps
> intermittent load needs to be divided over two pins.
> > Thanks
> > Tim
>
>
> Splitting it onto 2 pins with 6", 22AWG
> ballast pigtails is never wrong . . .
> but the super-pin might be okay.
>
> What accessory are you talking about?
>
>
> Bob . . . -Mat==============
>
>
> *
>
>
> *
>
>
________________________________________________________________________________
Subject: | Re: Std density D sub pins. |
And what is a "super pin"?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420851#420851
________________________________________________________________________________
Subject: | Re: Std density D sub pins. |
And what is a "super pin"?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420852#420852
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Std density D sub pins. |
At 12:31 PM 3/22/2014, you wrote:
>This is for a GTN 650 GPS/NAV/COMM. All the grounds out of that box.
>Tim
Okay, I'm seeing grounds on P1001, 1004 and 1003
that start out as multiple pins and splice down
to single conductors of 18 or 20AWG depending on
system voltage for a total of 7 wires.
Without conversation with the folks who set it
up, the rationale is not known to us. I've seen
this 'pin doubling' on a variety of radios over
the past 20 years.
One thing you could do is run individual 20AWG
wires from ALL 7 pins on the radio to independent
pins in the ground bus. This would cover a host
of rationals from quest for low impedance groung
path (shaky), redundancy (a little less shaky)
or load sharing in the pins (which is my best
guess).
I sold this philosophy onto the GQM163 super
sonic sea skimmer about 10 years ago.
http://tinyurl.com/7h9h76r
I think if it were my airplane, I'd go with
7 separate wires in bundle to the ground bus.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Std density D sub pins. |
At 02:17 PM 3/22/2014, you wrote:
>
>And what is a "super pin"?
Somebody, I think Garmin, spec'd a special
pin for d-sub connectors that would accept
larger than 20AWG wire. This is extra long
such that the crimp happens outside the connector
housing.
I'm mystified by this product . . . in no way
does it improve on the current rating of the
individual pin, only the ability to attach
wires rated for a lot more current than the
pin . . . wouldn't use one myself.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: P-Leads for a Seawind |
Oh Great Guru:
Thank you sir . . . I'll endeavor to live up
to your expectations . . .
I am installing a dual efis single ahrs GRT system with remote eis in
a Seawind. I am installing dual alternator dual battery electrical
system per your Z-14 schematic with parts from B & C.
Okay, you've got more SYSTEM reliability than
most twin-engine, TC aircraft . . .
Having experienced multiple electrical failures in 20 yrs. of a '63
Cherokee and already one alternator failure in 5yrs of my current '78
C-182RG, I'm dead set on having a few backup "steam" gages.
Perhaps "living confidence" as opposed to "dead disappointment"
is the better term . . .
Using the 10.4" EFIS displays, I don't have much panel space to play
with. There's just enough room under the EFIS's on the PIC side for 2
1/4 airspeed and manifold pressure gages, a Tiny Tach and a MicroTim
altimeter, which have internal batteries.
Why the batteries? You got more sources of 'juice'
in this airplane than Jonnie Appleseed has apples . . .
Emacs!
GRT connects to the P-leads on each mag with a 39 or 27 Kohm
resistor, claiming the resistor will act as a fuse if there's a
problem in the EIS.
The resistor isolated signal tap is a time honored,
well proven technique for sampling the p-lead
signals.
Tiny Tach people want me to drill a hole in the plug wire cap and
wrap several turns of "antenna" around a plug wire insulation. This
"antenna" wire insulation is about .06" diam. The plug insulation is
a close fit inside the rubber plug that seals the mag. The mag is
pressurized from my supercharger. A good seal is desirable. I
discussed this problem with a TinyTach tech and he allowed a direct
connection is not their recommendation, but the tiny resistor might
be o.k., especially if one also included a tiny fuse (my suggestion.)
I am suspicious of his design. Getting into
a spark-plug wire to sample engine rpm borders
on . . . well . . . I'll be nice. I 'sampled'
the #1 plug wire on a Baron WWAAAYyyyy back when
for the purpose of driving a propeller synchronizer
system.
For that task, I found that one could detect the
CURRENT in the plug wire from OUTSIDE the shield
with a toroidal current transformer. Got a nice
signal consistent with firing of #1 cylinder. But
getting 'under the shield' is unnecessary . . .
particularly for the purpose of measuring RPM.
See if this guy will email me a copy of his
schematic . . . honorable non-disclosure agreements
assumed . . . and I'll see if there's a way to
do more sanitary job of integrating his product
onto airplanes.
Alternatively, send me your tach and I'll
do some non-invasive investigations as to
the nature of its needs for an input signal.
My question: How do I select a fuse? If I connected at the mag
where the EIS goes, I would have twenty five feet of coax to get to
the TinyTach. If I connect at the panel, not more that one foot.
If the tach cannot be satisfied with perfectly
good data available at the magneto switch, I'd
look for a better product.
Another question: Is Bogert the only place in the world I can get
P-Leads for my TCM mags? $90 ea. for the smallest 30" leads seems
awfully high. and they are charging $3 or $4/ft. for each additional
foot. (14AWG MIL-C-27500 retails for $1.47 in Spruce.) Their
catalog only goes to 20 ft. & I need closer to 25. Since I'd have to
cut in anyway, couldn't I just buy the minimum 30" and splice in more
coax with soldersleeves?
Don't use factory fabricated p-leads. They're
priced for the captive, TC aircraft market.
You don't need 14 AWG wire either. Here's
a good source for 16 AWG at 50-cents/foot
http://tinyurl.com/nczzsfa
Poke around on eBay and you might come up
with some 20 or 18AWG which is more appropriate.
Build your own P-leads.
I have some shielded 22AWG trio wire left.
You could used this stuff and just parallel
up the strands. It's NOT critical.
You may wonder why two great big EFIS displays. GRT is the only one
to easily allow live video input. Seawind drivers are installing
cameras in their tip floats to watch the hull approach glassy
water--makes for "greasers" on pavement a possibility too. (My dirty
old men copilots want to plug in a dvd player and watch dirty movies
on the way to Oshkosh.)
What ever floats your seaplane my friend.
That's a really impressive machine. Lets
not make it any more difficult than necessary
to meet requirements.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: P-Leads for a Seawind |
I forgot to ask. Are your magnetos relatively new
or are they the the legacy Bendix mags? The older
mags have a knurled nut that holds the 'cigarette
terminal' in the connection well on the back of
the mag.
If you build your own p-leads for older mags,
those parts may be hard to find . . . but there
are folks on the AeroElectric-List that can
help.
Bob . . .
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
From: | "user9253" <fransew(at)gmail.com> |
There has been a recent discussion on VansAirforce about over-voltage problems. http://www.vansairforce.com/community/showthread.php?t=111102
Since over-voltage protection does not cost much or weigh much, I think that it
is worthwhile having, considering the damage that could be done by too high voltage.
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420931#420931
________________________________________________________________________________
From: | D L Josephson <dlj04(at)josephson.com> |
The concept of a "fuse" to keep faults in a tachometer from disabling an
ignition needs to be stamped out, it is a dangerous misconception. I
know of at least one incident where this almost caused a fatal crash. It
takes very little current through a P lead from a magneto or points wire
in a Kettering ignition to disrupt performance of the ignition. Can you
depend on this amount of current blowing a fuse? Is the resistor going
to open if there is a fault? Is the engine going to keep running well if
the far end of the resistor is shorted to ground or +12? Not unless it
has been tested to do so.
There are many tach designs that work without an ignition pickup. VDO
and other companies make programmable tachs that can be set to take a
signal from one phase of an alternator output, or an inductive pickup
from a flywheel or magneto case. Proper design of a tach could also
yield failsafe operation but that's still putting a lot of faith in
something you haven't tested. The "proof by assertion" that I've seen
from a few instrument vendors isn't really confidence-inspiring.
--
David Josephson
________________________________________________________________________________
From: | "R. curtis" <mrspudandcompany(at)verizon.net> |
Subject: | New Over-Voltage Protection Architecture |
> Since over-voltage protection does not cost much or weigh much, I think
> that it is worthwhile having, considering the damage that could be done by
> too high voltage.
Over voltage protection is recommended for an
externally regulated alternator. However, this
has been kicked around for the internally regulated
unit, and I am not sure that there is, as yet, a good
fool proof, method for this alternator.
Roger
--
Do you have a slow PC? Try a Free scan http://www.spamfighter.com/SLOW-PCfighter?cid=sigen
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
I was plagued by overvoltages on my externally regulated alternator, until I
found a permanent, fool-proof solution:
Schematic:
http://www.vx-aviation.com/rv-9a/photos/Electrical/Regulator_relay_app.jpg
This circuit bypasses the problematic alternator breaker - master switch
loop - wiring loop by connecting the master bus directly to the voltage
regulator through a fuselink and a relay. Since I have the battery and
contactor on the firewall, the total wiring length for this is about 20",
with minimal voltage drops. Ensure that you spray the relay connections
with Corrosion-X or bed them in silicone grease (DC4).
OVP still works normally.
A side effect is that almost all alternator noise disappeared. I used to
hear wig-wags and strobe noise in my headset, now it's gone. Voltage is
rock-solid and does not vary with load.
This design should also work with an internally regulated alternator without
OVP. The ones with OVP should have a circuit breaker instead of the
fuseable link. Downside to that is that the CB should be located close to
the alternator and cannot be reset in flight.
Cheers,
Vern
-----Original Message-----
From: user9253
Sent: Monday, March 24, 2014 9:57 AM
Subject: AeroElectric-List: Re: New Over-Voltage Protection Architecture
There has been a recent discussion on VansAirforce about over-voltage
problems. http://www.vansairforce.com/community/showthread.php?t=111102
Since over-voltage protection does not cost much or weigh much, I think that
it is worthwhile having, considering the damage that could be done by too
high voltage.
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420931#420931
________________________________________________________________________________
Subject: | Re: DIY CBOVM: variations on a theme |
From: | "user9253" <fransew(at)gmail.com> |
I built Bob's circuit. To test it, I wired it in series with an automotive lamp to a DC-DC converter like this one: http://tinyurl.com/kmpqcb8
I slowly turned the pot to increase the voltage. The lamp illuminated at almost
17 volts. Since my Rotax rectifier/regulator puts out about 13.8 volts, I decided
to lower the set point of the over-voltage protector by substituting a
5.1K resistor for the 5.6K. Now the test lamp comes on at 16.2 volts. When the
voltage increases above 15.8, the circuit becomes sensitive. Just touching
the circuit with a digital voltmeter probe is enough to fire the SCR. Using
a different voltmeter had the same affect. No doubt that in an electrically noisy
environment like an airplane, the circuit will trip at 15.8 volts. That
is not a problem though. 15.8 volts is 2 volts above my aircraft system voltage.
If spring weather ever comes to Michigan, I will install it in the airplane.
Thanks for designing the circuit, Bob. You are my mentor.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420938#420938
________________________________________________________________________________
From: | K <kleh(at)dialupatcost.ca> |
Yes "Fuse" is not the terminology I'd use for such a resistor.
Agree that the resistor definitely needs to be large enough value that
it won't interfere if grounded and testing it should not be overlooked.
Where I've seen this go bad was when a wire was run to the resistor
mounted in the tach. With age and moisture the wire insulation started
breaking down. The resistor should be physically at the ignition pick
off point, NOT remotely located. I apply the same concept to picking off
a fuel flow signal from an electronic fuel injector.
Ken
On 24/03/2014 1:37 PM, D L Josephson wrote:
>
>
> The concept of a "fuse" to keep faults in a tachometer from disabling an
> ignition needs to be stamped out, it is a dangerous misconception. I
> know of at least one incident where this almost caused a fatal crash. It
> takes very little current through a P lead from a magneto or points wire
> in a Kettering ignition to disrupt performance of the ignition. Can you
> depend on this amount of current blowing a fuse? Is the resistor going
> to open if there is a fault? Is the engine going to keep running well if
> the far end of the resistor is shorted to ground or +12? Not unless it
> has been tested to do so.
>
> There are many tach designs that work without an ignition pickup. VDO
> and other companies make programmable tachs that can be set to take a
> signal from one phase of an alternator output, or an inductive pickup
> from a flywheel or magneto case. Proper design of a tach could also
> yield failsafe operation but that's still putting a lot of faith in
> something you haven't tested. The "proof by assertion" that I've seen
> from a few instrument vendors isn't really confidence-inspiring.
>
> --
> David Josephson
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: DIY CBOVM: variations on a theme |
At 01:41 PM 3/24/2014, you wrote:
I built Bob's circuit. To test it, I wired it in series with an
automotive lamp to a DC-DC converter like this one: http://tinyurl.com/kmpqcb8
I slowly turned the pot to increase the voltage. The lamp
illuminated at almost 17 volts. Since my Rotax rectifier/regulator
puts out about 13.8 volts, I decided to lower the set point of the
over-voltage protector by substituting a 5.1K resistor for the
5.6K. Now the test lamp comes on at 16.2 volts. When the voltage
increases above 15.8, the circuit becomes sensitive. Just touching
the circuit with a digital voltmeter probe is enough to fire the
SCR. Using a different voltmeter had the same affect. No doubt that
in an electrically noisy environment like an airplane, the circuit
will trip at 15.8 volts. That is not a problem though. 15.8 volts
is 2 volts above my aircraft system voltage. If spring weather ever
comes to Michigan, I will install it in the airplane.
That should not be so sensitive to probing.
How is this circuit packaged? Can you send me a pucture?
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
At 01:06 PM 3/24/2014, you wrote:
><sprocket@vx-aviation.com>
>
>I was plagued by overvoltages on my externally regulated alternator,
>until I found a permanent, fool-proof solution:
Can you post a schematic of your original installation?
When you say you were plagued with over-voltages . . .
was your ov protection tripping a lot . . . or
were there ov events for which there was no
installed protection?
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: P-Leads for a Seawind |
At 12:58 AM 3/25/2014, you wrote:
Thanks for taking an interest. I called LyCon in Visalia, Ca. where I
had the engine modified and he clued me the type # is 66LN-21
and he had the parts in stock. They're on the way.
Good show . . .
I'll get 50ft. of 20 AWG MIL-C-27500 & I'm good to go.
Agreed . . .
I could still use some advice as to how to connect to a TinyTach at the panel.
GRT has me pick off tach signal from ea. mag p-lead at the engine
through a 39 or 27Kohm resistor, claims the resistor will blow like a
fuse if anything shorts in their EIS
TinyTach wants 5 to ten turns of the core wire of their coax around
one plug wire just inside the cap on the mag. Mechanically, this is
not so hot, as there is a rubber sealing plug between the plug wire
insulator and the socket of the mag holding supercharger pressure.
How do I reconcile 200v or so of high p-lead current with 30kv or so
of low current at a plug wirefor a direct connection? For an extra
10bucks. TinyTach will supply enough wire to get back to the engine.
Would it be satisfactory to cut the shield of a plug wire outside of
the mag, wrap their 5 to 10 turns of insulated "antenna" coax core
around the plug insulator, and cover it back up with braid and solder
sleeves? Sounds pretty messy, doesn't it? I sure would like to pick
the signal off clean at the ignition switch.
This supplier is oblivious to the nature
of the stuff he's attempting to monitor.
He also doesn't understand the way things
are done on airplanes.
Tell him that's where you want to sample
engine rpm . . . on wires that are already
in place. Adding new wire from a plug wire
is not only sloppy, it's an invitation
to radiated ignition noise.
Is this your ONLY tach option? The whole
world builds tachs. I'd dump this product.
The $time$ your going to spend to educate
him and perhaps to adapt his product to your
airplane is more than the tach is worth.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
At 11:57 AM 3/24/2014, you wrote:
>
>There has been a recent discussion on VansAirforce about
>over-voltage
>problems. http://www.vansairforce.com/community/showthread.php?t=111102
>Since over-voltage protection does not cost much or weigh much, I
>think that it is worthwhile having, considering the damage that
>could be done by too high voltage.
Have you cited the right thread? These postings are all
dated back in the 2007-08 time frame.
Long time members on the List will recall some
exchanges with Paul M who was really excited
about crowbar shutdown techniques . . . he
railed on for years choosing to ignore thousands
of applications for the technique in both
experimental and certified aircraft.
Seems some of his buddies tried to build the
DIY circuit and had some nuisance tripping problems.
I made some modifications to the circuit based on
their valuable feedback. But in any case, like
any device that 'triggers on a voltage threshold'
there are physical constraints for reliable performance
not the least of which is compact size and perhaps
metallic, grounded enclosure.
The etched circuit board for the production
version is only about .6" wide by 1" long
and takes surface mount components. VERY small
aperture for potentially offending signals.
Bob . . .
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
From: | "Eric M. Jones" <emjones(at)charter.net> |
Sensitron, a NY based manufacturer of electronic modules for aircraft, used to
make a really beefy transient voltage suppressor. I recall it was thousands of
dollars and was potted into a heatsink. It did OVP and/or load dump prevention
with one basic part...parallel zeners I think.
They also make solid-state relays and assorted electro-whizzies mostly for 28V
military aircraft. They have a great catalog worth perusing.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420982#420982
________________________________________________________________________________
From: | Sam Marlow <sam.marlow(at)roadrunner.com> |
Subject: | Re: Marker Beacon Remote Indicators? |
BobsV35B(at)aol.com wrote:
> Good Afternoon Bob and Bill,
> May I ask why you want the marker beacon indication? It is/was part
> of the low frequency range system which was shut down over sixty years
> ago. It has been retained for use with a few ILSs and some NDB
> approaches, but such use is rapidly being discontinued.
> I know of no fix designated by a marker beacon that cannot be found
> via some other legal IFR data.
> That is especially true if one has an IFR approved GPS installed.
> There is nothing wrong with having a marker beacon receiver installed,
> but you can eliminate an antenna and some wiring by getting rid of it.
> You might even be able to save some panel space.
> My vote is to forget about the marker Beacon Receiver.
> Happy Skies,
> Old Bob
> *
>
>
> *
We at the airlines still use them on Cat2 approaches..................
________________________________________________________________________________
Subject: | Re: New Over-Voltage Protection Architecture |
From: | "user9253" <fransew(at)gmail.com> |
> Have you cited the right thread? These postings are all
> dated back in the 2007-08 time frame.
Hmm, the link works for me. http://www.vansairforce.com/community/showthread.php?t=111102
All 12 posting in this thread are from the last 2 or 3 days.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420992#420992
________________________________________________________________________________
From: | "Roger & Jean" <mrspudandcompany(at)verizon.net> |
Subject: | Re: New Over-Voltage Protection Architecture |
>
>> Have you cited the right thread? These postings are all
>> dated back in the 2007-08 time frame.
>
> Hmm, the link works for me.
> http://www.vansairforce.com/community/showthread.php?t=111102
> All 12 posting in this thread are from the last 2 or 3 days.
Perhaps Bob was looking at the (Join Date) for these posters and not
the actual posting date.
Roger
________________________________________________________________________________
From: | BobsV35B(at)aol.com |
Subject: | Re: Marker Beacon Remote Indicators? |
Good Afternoon Sam,
Just for kicks, I called up the ILS Rwy 9L CAT II & III at KORD. I find
that to execute that approach you must have a GPS, airline or no airline. It
uses many GPS distance fixes for the approach and the distances are from the
ISAJ GPS fix which is colocated with the inner marker. Put ISAJ in lieu of
the inner marker in your op specs and I will bet two bucks against a
doughnut that it will be approved?
Happy Skies,
Old Bob
In a message dated 3/25/2014 9:13:42 A.M. Central Daylight Time,
sam.marlow(at)roadrunner.com writes:
--> AeroElectric-List message posted by: Sam Marlow
BobsV35B(at)aol.com wrote:
> Good Afternoon Bob and Bill,
> May I ask why you want the marker beacon indication? It is/was part
> of the low frequency range system which was shut down over sixty years
> ago. It has been retained for use with a few ILSs and some NDB
> approaches, but such use is rapidly being discontinued.
> I know of no fix designated by a marker beacon that cannot be found
> via some other legal IFR data.
> That is especially true if one has an IFR approved GPS installed.
> There is nothing wrong with having a marker beacon receiver installed,
> but you can eliminate an antenna and some wiring by getting rid of it.
> You might even be able to save some panel space.
> My vote is to forget about the marker Beacon Receiver.
> Happy Skies,
> Old Bob
> *
>
>
> *
We at the airlines still use them on Cat2 approaches..................
Do Not Archive
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | The lithium saga slogs onward . . . |
In my quest to identify suppliers of lithium
batteries who will share operational details of
their BMS (battery management system) AND useful
contained energy plots, few suppliers have demonstrated
an interest in satisfying the unique curiosity of
those who build and fly airplanes.
So far, EarthX is the only one who has responded
positively. I have documentation that describes
their BMS operating philosophy. No family of
discharge curves yet . . . but them, most of their
customers are narrowly focused on engine cranking
cupcakes with a frosting of weight reduction.
I need to wrap of installment IV of the battery
series for Kitplanes . . . as of this moment, I'm
still short the necessary information to beat the
drums in favor of ANY commercial off the shelf
lithium product for OBAM aircraft.
My misgivings are NOT rooted in either disappointment
for weight savings or ability to get the engine started.
The problem is centered on knowing what we don't know . . .
exactly what size battery is needed to replace the
legacy SVLA products in which we have considerable
confidence.
Watch this space . . .
Bob . . .
________________________________________________________________________________
Subject: | Re: DIY CBOVM: variations on a theme |
From: | "user9253" <fransew(at)gmail.com> |
I repeated testing of the over-voltage circuit today, doing a better job of connecting
wires. If the voltage is steadily increased, the SCR fires at 16.2 volts.
But if the voltage is set at 16.0 volts and held there, the SCR would fire
after waiting a couple of minutes. Probing the input with a voltmeter intermittently
caused the SCR to fire only when the voltage was above 15.9. Circuit
instability, if any, is within 0.1 volt of the set-point. The adjustable voltage
power supply only cost $6. Who knows how stable that is. The components
are all through-hole, not surface mounted, and are mounted to a 1 x 2 inch
area of PCB. I am happy with the circuit.
I intend to connect the over-voltage circuit in series with a relay coil that
is powered by a 3 amp fuse.. The normally closed contacts of the relay will
be in series with the AC output of the permanent magnet dynamo. In case of high
voltage, the SCR will fire, connecting one leg of the coil to ground to energize
the relay, opening the AC circuit to the rectifier/voltage regulator. The
SCR will continue to hold the relay energized until battery power is disconnected
from the relay coil.
This will not be a crowbar type of over-voltage protection. So no circuit breaker
is required. High voltage will not blow the fuse.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421067#421067
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Subject: | Re: DIY CBOVM: variations on a theme |
Joe,=0A=0A1. How much power can the dynamo produce?- =0A2. Are there only
2 wires for the AC output? (I've never worked w/ a PM type alternator but
most non-PM machines have 3 wires for AC output)=0A3. As you probably alrea
dy know, on some relays, the current-handling capability of the NC contacts
is less than the NO contacts=0A=0A=0A-Jeff=0A=0A=0A=0A____________________
____________=0A From: user9253 <fransew(at)gmail.com>=0ATo: aeroelectric-list@
matronics.com =0ASent: Wednesday, March 26, 2014 7:40 AM=0ASubject: AeroEle
ctric-List: Re: DIY CBOVM: variations on a theme=0A =0A=0A--> AeroElectric-
List message posted by: "user9253" =0A=0AI repeated test
ing of the over-voltage circuit today, doing a better job of connecting wir
es.- If the voltage is steadily increased, the SCR fires at 16.2 volts.
- But if the voltage is set at 16.0 volts and held there, the SCR would f
ire after waiting a couple of minutes.- Probing the input with a voltmete
r intermittently caused the SCR to fire only when the voltage was above 15.
9.- Circuit instability, if any, is within 0.1 volt of the set-point.-
The adjustable voltage power supply only cost $6.- Who knows how stable t
hat is.- The components are all through-hole, not surface mounted, and ar
e mounted to a 1 x 2 inch area of PCB.- I am happy with the circuit.=0A
- I intend to connect the over-voltage circuit in series with a relay coi
l that is powered by a 3 amp fuse..- The normally closed contacts of the
relay will be in series with the AC output of the permanent magnet dynamo.
- In case of high voltage, the SCR will fire, connecting one leg of the c
oil to ground to energize the relay, opening the AC circuit to the rectifie
r/voltage regulator.- The SCR will continue to hold the relay energized u
ntil battery power is disconnected from the relay coil.=0A- This will not
be a crowbar type of over-voltage protection.- So no circuit breaker is
required.- High voltage will not blow the fuse.=0AJoe=0A=0A--------=0AJoe
Gores=0A=0A=0A=0A=0ARead this topic online here:=0A=0Ahttp://forums.matron
==============
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Continental Motors magneto data |
Hat tip to Neal George who has provided
us with a helpful library of service and
training data on Continental's magneto systems.
List members are invited to review the documents
available at:
http://tinyurl.com/llpc5lj
. . . and download as their interest and needs
dictate.
Bob . . .
________________________________________________________________________________
From: | K <kleh(at)dialupatcost.ca> |
Subject: | Re: DIY CBOVM: variations on a theme |
In regards to stability you might check that there is a capacitor across
the voltage reference diode and another from the SCR gate to ground. If
you happen to have an old circuit diagram dated before about 2005 it may
not show that update.
One nice thing about the crowbar and circuit breaker in the Z diagrams
is that the voltage is brought under control immediately when the SCR
fires. If I understand your post it sounds like your implementation
waits for the relay to open and for any subsequent arcing to extinguish.
Perhaps that is good enough but it seems preferable to use the circuit
breaker as per the Z diagrams so that the SCR clamps the voltage faster.
Might be other small advantages as well such as a subsequent dead
battery could not cause the alternator to come back on line.
Ken
On 26/03/2014 10:40 AM, user9253 wrote:
>
>
> I repeated testing of the over-voltage circuit today, doing a better
> job of connecting wires. If the voltage is steadily increased, the
> SCR fires at 16.2 volts. But if the voltage is set at 16.0 volts and
> held there, the SCR would fire after waiting a couple of minutes.
> Probing the input with a voltmeter intermittently caused the SCR to
> fire only when the voltage was above 15.9. Circuit instability, if
> any, is within 0.1 volt of the set-point. The adjustable voltage
> power supply only cost $6. Who knows how stable that is. The
> components are all through-hole, not surface mounted, and are mounted
> to a 1 x 2 inch area of PCB. I am happy with the circuit. I intend
> to connect the over-voltage circuit in series with a relay coil that
> is powered by a 3 amp fuse.. The normally closed contacts of the
> relay will be in series with the AC output of the permanent magnet
> dynamo. In case of high voltage, the SCR will fire, connecting one
> leg of the coil to ground to energize the relay, opening the AC
> circuit to the rectifier/voltage regulator. The SCR will continue to
> hold the relay energized until battery power is disconnected from the
> relay coil. This will not be a crowbar type of over-voltage
> protection. So no circuit breaker is required. High voltage will
> not blow the fuse. Joe
>
> -------- Joe Gores
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=421067#421067
>
>
________________________________________________________________________________
Subject: | Re: DIY CBOVM: variations on a theme |
From: | "user9253" <fransew(at)gmail.com> |
Jeff,
1. The Rotax 912 dynamo can generate up to about 20 amps. Although many recommend
not loading it to more than 16 amps. My plane uses about 10 amps.
2. Yes, the AC output has two wires and is single phase.
3. If I am interpreting this data sheet correctly http://pewa.panasonic.com/assets/pcsd/catalog/cb-catalog.pdf
the normally closed contacts can handle 30 amps. I suspect that, over the long
term, corrosion due to lack of exercise will be more of a problem than the contact
rating.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421074#421074
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: New Over-Voltage Protection Architecture |
>Hmm, the link works for me.
>http://www.vansairforce.com/community/showthread.php?t=111102
>All 12 posting in this thread are from the last 2 or 3 days.
Yeah, had a momentary short between the heaphones.
Let's parse the narrative . . .
Last Wednesday I flew from Melbourne to Hobart in my RV-7 (about an
hour of the 2.5hr flight is over water - Bass Strait). Faultless day,
faultless flight. Yesterday I jumped in my RV and flew from Hobart to
Bruny Island (short flight - no problems). When I departed Bruny
Island I got a Low Voltage Warning on my EFIS a couple of minutes
after take off. I have an EXP2 Buss DC Load Center with indicator
panel and GRT EFIS. EXP2 Indicator panel showed that the Alternator
had switched off and the GRT was showing 13.3Volts and dropping.
"Dropping" is not very quantified but the initial bus voltage
excursion will be rather steep. A battery charges a 14.5 and
discharges at 12.5 . . . so the first few seconds, probably
less than a minute will show a steep drop of more than
a volt.
[]
Note that this exemplar battery loaded to 1C
starts 'working' at just over 12 volts. If he
had been fitted with a flight worthy, 17 Ah battery
and could reduce his loads to say 4A (.2C) his
trip home would have been uneventful . . .
I know you shouldn't turn the alternator off when the engine is
running however I cycled the Alt Switch to see if i could get it to
reset but no change resulted.
There is no rational prohibition for turning the alternator
on/off while the engine is running . . . particularly
if there's a flight worthy battery in service.
At this point I was over water so I requested a direct track to
Hobart and landed to check it out (while I still had some volts). By
the time I landed I didn't have enough volts to start the engine. I
recharged the battery overnight. This morning I started the engine
and the Alternator came back on line and operated as normal. After
warm ups I obtained a clearance and departed Hobart....3 mins later
the Alternator failed again and I returned to Hobart.
What's wrong with this story? After the FIRST failure of
the alternator, the battery was incapable of supporting
sustained flight for more than a few minutes.
Before I shut down I momentarily switched the master switch off and
then immediately back on - this recycled the alternator and it was
operating normally again. I suspected it may have been an over
voltage condition because the EXP2 Buss has over-volt protection
which turns off the Alternator and you have to remove battery power
to reset it. I did a ground run for approximately 3 minutes at
2200rpm but it continued to operate normally (i thought this might
cause it to fail). I shut down and removed the cowls and checked the
belt and checked the connectors. Removed and refitted the connector
on the back of the Alternator - all seemed fine. Following this I
replaced the cowls and then inspected the EXP2 Buss to see if there
were any loose connections. All seemed OK. I started the engine again
and Alternator was operating normally after run-ups and a higher rpm
check. I taxied out to the runway and I watched the indicator panel
on departure...shortly after take off (before I had reduced the rpm)
the indicator panel showed a high voltage warning which then reverted
to a low voltage warning probably due to over volt protection kicking
in. I completed the circuit and landed, tied down my RV and came to
the conclusion that I wasn't going to fly back over Bass Strait in a
hurry so I jumped on a commercial flight home.
The peek-n-poke is a good and necessary part
of the troubleshooting activity. His decision
to use alternate transportation was prudent.
We've discussed system reliability philosophies
here on the list for many years. Crafting design
goals should be followed with design, testing
and maintenance to those goals.
If this gentleman had crafted a plan-b with capable
and confident endurance (can anybody say Z-13/8?)
it's unlikely that this story would have been
written. Yes, things break on airplanes. The real
story here is not the difficulty with his alternator
or it's associated controls. It's about his
ABSOLUTE DEPENDENCE on the alternator for comfortable
transition over deep water.
So now the dilemma - I didn't bring the Alternator home with me so I
can't bench test it. My thoughts are to purchase a replacement
alternator and take it to Hobart and fit it to see if the problem
goes away. If not, then I will have a spare alternator and the
problem is more likely to be a fault in the over volt protection on
the EXP2 Buss.
Has anyone had a similar experience with the Vans 60amp Alternator
and EXP2 Buss combination? If yes - what conclusions did you come to?
I have had a previous Internal Voltage Regulator failure with this
same Alternator which was repaired. I believe the previous failure
may have been caused by turning on the alternator switch after start
up. Ever since that point I have been turning on the Alternator
switch prior to start up and turning off after shutdown.
My Engine/Alternator has now done 193 hours.
Any help/thoughts would be appreciated because when I fly back to
pick up my RV I want to be confident that I can get it home.
All the rest of this narrative is irrelevant to
the core issues illustrated. This story isn't
about resolving an alternator problem, it's about
lack of SYSTEM reliability.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: DIY CBOVM: variations on a theme |
At 10:23 AM 3/26/2014, you wrote:
>Joe,
>
>1. How much power can the dynamo produce?
Most are limited to about 30A. The single phase
(2-wire) offerings by B&C, Rotax and others
are in the 8-20A class. The 3-phase, 3-wire
devices for the larger 'tractors' can
get you 30A or so.
The problem with PM alternators is not the
power generating ability of the mechanism but
the power handling ability of the rectifier/
regulator. Unlike the 3-phase automotive
alternator that runs output power through
simple junction diodes. The regulator carries
only a couple amps of field current.
In the PM regulator, total output current of
up to 30A flows through regulator semiconductors.
Hence the heat sinks and limited size with
respect to power.
Bob . . .
________________________________________________________________________________
Subject: | Re: DIY CBOVM: variations on a theme |
From: | "user9253" <fransew(at)gmail.com> |
Ken,
Thanks for suggesting the capacitors. The circuit is stable unless the voltage
gets very close to the trip point. That is OK with me as long as there is no
nuisance tripping. Time will tell.
Good point about the crowbar circuit acting immediately by clamping the supply
to ground. The data sheet for my relay says it will operate in 15 milliseconds.
I am hoping the battery will limit the voltage until the relay contacts open.
I will try to land before the battery runs down enough (almost completely
dead) to drop out the relay.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421078#421078
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | The lithium saga slogs onward . . . |
FIY . . . got a peek inside this battery
from True Blue Power . . . who
has achieved the first TSO'd offering for
GA aircraft.
http://tinyurl.com/lxh6wqm
The battery is 17Ah (in AIRCRAFT Ah at
1-hour - not a 20 hour rate) and 24V. Weighs
about 16 pounds. So a 12v, 17Ah battery
would be about half that weight.
TB17
This battery is an array of 56 cylindrical
cells not unlike these 26650 cells available
from a variety of sources.
1pc 3.2V LiFePO4 Li-ion LFP26650 energy type 3200mAh flat cap b
In rough numbers, this cell is a 10Wh storage
medium. 56 cells x 10Wh suggests you can expect about
560Wh from the array. This is consistent with
nameplate energy rating for the battery at 430Wh.
Being one of the few batteries where detailed
system integration data are available, we
can begin to size the task for incorporation of
this or similar products into airplanes.
A 12V version of the battery would be 215Wh
so if you have an electrically dependent engine
with a 100W service load, you could expect about
2 hours endurance for just an engine. Peel off
50-73 watts for electro-whizzies, your battery
only endurance expectations are just over 1
hour for new battery, just under 1 hour for
end-of-life battery.
Now for the sobering facts. There are two
circuit boards in the battery management system
(BMS). One is just under the heat-sink fins on
top of the battery. It's populated with a goodly
number of FAT transistors, probably N-MOS FETs
in TO-247 plastic packages.
The other board occupies a whole side of the battery
and is covered with perhaps 2-3 dozen surface mount
ic's and lots of jelly-bean parts. There's probably
more silicon in this battery than in your ICOM comm
transceiver, gps and transponder combined.
Further, I believe this battery will sell for about
$3200; so one might ball-park a 12v battery at $1600.
Of course, that's 'airplane' pricing that carries
the burden of TSO certification.
This product is the leading edge example of what it
takes to get approval for TC aviation. Other
product MIGHT offer similar capabilities for $less$
if they've not run the TSO gauntlet.
Just giving you guys a heads-up on what I'm discovering
as that battery articles move forward . . .
The REAL significance of this discovery exercise
is that to get 1-hour of battery only endurance in
a 200W airplane will take an array of 28 lithium
cells of the size cited above. This means that batteries
like this
[]
http://tinyurl.com/k8yhurl
which are 4 x 4 arrays of similar cells probably
fall short of the 1-hour endurance hypothetical
half-a-True-Blue endurance cited above.
Further, this pretty little red thing cannot feature
the same degree of battery management that's built
into the True Blue product.
Tying this back to the venerable PC680 . . .
Emacs!
We see that teh PC680 at the 1-hour rate is a 12.3Ah battery
when new. A 175W airplane will say lit up for about 45 minutes on
a new battery.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: DIY CBOVM: variations on a theme |
At 11:45 AM 3/26/2014, you wrote:
>
>In regards to stability you might check that there is a capacitor
>across the voltage reference diode and another from the SCR gate to
>ground. If you happen to have an old circuit diagram dated before
>about 2005 it may not show that update.
>
>One nice thing about the crowbar and circuit breaker in the Z
>diagrams is that the voltage is brought under control immediately
>when the SCR fires. If I understand your post it sounds like your
>implementation waits for the relay to open and for any subsequent
>arcing to extinguish. Perhaps that is good enough but it seems
>preferable to use the circuit breaker as per the Z diagrams so that
>the SCR clamps the voltage faster. Might be other small advantages
>as well such as a subsequent dead battery could not cause the
>alternator to come back on line.
For the run-of-the-mill ov conditions with a good
battery, an ov even is not one of extreme urgency.
The ships air-worthy battery will stand off a runaway
alternator for significant intervals. If one waited
100 mS to evaluate an ov condition for a true runaway
alternator, it wouldn't be a bad thing.
In fact, the next generation ov module will do just
that. Sensing an ov condition start a 100mS timer
that continue to run as long as the voltage does not
drop back below 16V before the timer runs out.
On the other hand, a second threshold at 20V assumes
no air worthy battery is present and an immediate trip
is initiated.
We're still going to pull down on the field supply
breaker . . .
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
I'm needing a nose-on picture of an OBAM aircaft
for use on the counter display for the AEC9012
programmable wig-wag at Osh . . .
Thanks!
Bob . . .
________________________________________________________________________________
Subject: | Re: Marker Beacon Remote Indicators? |
BobsV35B(at)aol.com wrote:
> What I am trying to do is help folks save money, space and weight on their airplanes.
>
> Seems any serious IFR pilot will have a GPS and, with a GPS, the marker beacon
becomes superfluous. Just trying to save the troops a few bucks and some
space in their flying machine.
>
> Happy Skies,
>
> Old Bob
>
I'm in the process of connecting my avionics. I installed a marker beacon antenna
only to discover that the audio panel I'm installing doesn't have marker beacon
indicators. I contacted the manufacture and they explained that marker beacon
transmitters will start to be decommissioned starting next year. So they
decided to remove that function.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421197#421197
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Photo needed |
At 07:29 PM 3/27/2014, you wrote:
>
>
>I'm needing a nose-on picture of an OBAM aircaft
>for use on the counter display for the AEC9012
>programmable wig-wag at Osh . . .
Thanks to all who have contributed to this
call for photos! I've received some very nice
suggestions . . . some of which are excellent
candidates for the cover of R13.
It has been suggested that I clarify my
original request. I'm crafting a counter-top
display for the AEC9012 programmable wig-wag.
I'd like have a full wing span, nose-on view
of an airplane on which I'll mount white leds
out on the wings . . . and paste the whole over
a background that emulates an in-flight scenario.
Hence, the photo need not . . . be of an airplane
in flight, sitting on the ground would be just
fine. Preferably a tricycle gear so that the
tail feathers are disposed in a 'level flight'
position to the nose.
Bob . . .
________________________________________________________________________________
From: | Jan de Jong <jan_de_jong(at)casema.nl> |
Subject: | Re: DIY CBOVM: variations on a theme |
That's another issue with a lithium battery - it does not keep OV down
well - even if not fitted with a BMS. And it seriously dislikes
overvoltage. It thus requires a fast OV switch at the alternator.
And if it has a BMS it will also have a battery OV cutoff switch built
in. Making the battery unavailable just when it is needed.
My conclusion has been that if I want Lithium I will have to make the
under/over cell voltage and cell temperature monitoring and top
balancing myself.
With backed up OV protection at the alternator.
And have the individual cells accessible to thermistors.
Jan de Jong
On 3/26/2014 8:45 PM, Robert L. Nuckolls, III wrote:
>
>
> At 11:45 AM 3/26/2014, you wrote:
>>
>> In regards to stability you might check that there is a capacitor
>> across the voltage reference diode and another from the SCR gate to
>> ground. If you happen to have an old circuit diagram dated before
>> about 2005 it may not show that update.
>>
>> One nice thing about the crowbar and circuit breaker in the Z
>> diagrams is that the voltage is brought under control immediately
>> when the SCR fires. If I understand your post it sounds like your
>> implementation waits for the relay to open and for any subsequent
>> arcing to extinguish. Perhaps that is good enough but it seems
>> preferable to use the circuit breaker as per the Z diagrams so that
>> the SCR clamps the voltage faster. Might be other small advantages as
>> well such as a subsequent dead battery could not cause the alternator
>> to come back on line.
>
> For the run-of-the-mill ov conditions with a good
> battery, an ov even is not one of extreme urgency.
> The ships air-worthy battery will stand off a runaway
> alternator for significant intervals. If one waited
> 100 mS to evaluate an ov condition for a true runaway
> alternator, it wouldn't be a bad thing.
>
> In fact, the next generation ov module will do just
> that. Sensing an ov condition start a 100mS timer
> that continue to run as long as the voltage does not
> drop back below 16V before the timer runs out.
>
> On the other hand, a second threshold at 20V assumes
> no air worthy battery is present and an immediate trip
> is initiated.
>
> We're still going to pull down on the field supply
> breaker . . .
>
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: DIY CBOVM: variations on a theme |
At 12:15 PM 3/31/2014, you wrote:
>
>That's another issue with a lithium battery - it does not keep OV
>down well - even if not fitted with a BMS. And it seriously dislikes
>overvoltage. It thus requires a fast OV switch at the alternator.
>And if it has a BMS it will also have a battery OV cutoff switch
>built in. Making the battery unavailable just when it is needed.
>
>My conclusion has been that if I want Lithium I will have to make
>the under/over cell voltage and cell temperature monitoring and top
>balancing myself.
>With backed up OV protection at the alternator.
>And have the individual cells accessible to thermistors.
Your perceptions of being inadequately informed
with respect to operating details of the various
lithium products are accurate.
There is no industry standard for the term "BMS".
I'm working the 4th installment on the series
of battery articles for Kitplanes. The past 7
weeks have been enlightening.
I'm not sure that alternator OV protection needs
to be anything beyond the ordinary . . . I'm still
stirring the stew of simple-ideas . . .
Bob . . .
________________________________________________________________________________
From: | Jan de Jong <jan_de_jong(at)casema.nl> |
Subject: | Re: DIY CBOVM: variations on a theme |
The implicit "trust us" attitude is in any case unwarranted. Full
specifications of the built-in electronics are absolutely necessary.
What I have seen is not very compatible with aircraft use. We do not
want OV cut-out built-in (should be done somewhere up in the charging
path). We probably do not want LV cut-out built-in either (saving the
battery may not always be the highest goal). But we want monitoring and
warning. And as a pilot I want to know about temperatures. When used
well (correct voltages and currents within limits, no recharging ever
after full discharge) the remaining danger is a manufacturing fault,
with temperature discrepancy the only available signal.
And a measure of top balancing is needed unless we are willing to adopt
a discipline of doing that externally. A certain minimum balancing
current per Ah, say 50mA or so is required. I've seen balancing currents
quoted for Chinese BMS products that are likely useless for any
realistic battery size (they may be intended for UPS batteries - very
long charging times and smallish charging currents).
And the balancing algorithm is often primitive - most balancers only
balance at the very end of the charging process by comparing a cell
voltage with a high limit-voltage, not during the charging process by
comparing a cell voltage with the voltages of other cells. The latter
allows good balancing with a lower alternator set voltage. In exchange
for a few percent of charge you get much longer life - apparently.
I wish you wisdom with the 4th article on batteries (great articles so
far, I approve of the current editor in chief of KP!)
Jan de Jong
On 3/31/2014 8:12 PM, Robert L. Nuckolls, III wrote:
>
>
> At 12:15 PM 3/31/2014, you wrote:
>>
>>
>> That's another issue with a lithium battery - it does not keep OV
>> down well - even if not fitted with a BMS. And it seriously dislikes
>> overvoltage. It thus requires a fast OV switch at the alternator.
>> And if it has a BMS it will also have a battery OV cutoff switch
>> built in. Making the battery unavailable just when it is needed.
>>
>> My conclusion has been that if I want Lithium I will have to make the
>> under/over cell voltage and cell temperature monitoring and top
>> balancing myself.
>> With backed up OV protection at the alternator.
>> And have the individual cells accessible to thermistors.
>
> Your perceptions of being inadequately informed
> with respect to operating details of the various
> lithium products are accurate.
>
> There is no industry standard for the term "BMS".
> I'm working the 4th installment on the series
> of battery articles for Kitplanes. The past 7
> weeks have been enlightening.
>
> I'm not sure that alternator OV protection needs
> to be anything beyond the ordinary . . . I'm still
> stirring the stew of simple-ideas . . .
>
>
> Bob . . .
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
At 03:40 PM 3/31/2014, you wrote:
>Bob,
>
>I couldn't find a plain front on shot that was suitable. I don't
>suppose the attached would be any good though?
>
>All the shots I sent are my own work.
Yes! That will work!
Thanks.
Unless you're submitting candidate photos for R13
front cover, know that Ed has nicely filled my needs
for the AEC9012 wig-wag display.
We're still compiling a library of R13 Cover
photos. Just as we did last time, I'll probably
pick 5 or 6 from what's offered and the AeroElectric-List
members will pick the winner.
Thanks to all who assisted with the current
project.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: DIY CBOVM: variations on a theme |
At 03:00 PM 3/31/2014, you wrote:
The implicit "trust us" attitude is in any case unwarranted. Full
specifications of the built-in electronics are absolutely necessary.
that will be a primary premise of the 'last' article.
What I have seen is not very compatible with aircraft use. We do not
want OV cut-out built-in (should be done somewhere up in the charging path).
This is certainly the legacy philosophy for lead-acid
and/or Ni-Cad batteries wherein the battery was a
'current sink' of demonstrable value for managing
a runaway generator/alternator.
But let's assume for the moment that one of our
future design goals is to craft and prove airworthiness
of an alternator-only operation protocol. Now we need
to show that the runaway alternator can be controlled
within the DO160/MilSTD704 envelope.
If that proves to be practical, then the electronics
in the battery need not assume any duties beyond those
for protecting the battery . . . the battery MIGHT be
relieved of duty for standing guard at the gates
standing off runaway alternators.
We probably do not want LV cut-out built-in either (saving the
battery may not always be the highest goal). But we want monitoring
and warning.
Yeah . . . but it depends on WHERE the l.v. cutout
occurs.
Toyota writes software intended to maintain their
lithium cells at some place between 30 and 85% capacity.
This is the ENERGY operating range that offers the
advertised cell life. But they don't force disconnect
the battery . . . as far as I've been able to learn
so far.
Depending on the BMS designer's charter from on-high . . .
he may well have other bounds. Without advocating for
any particular energy range . . . I'll suggest that any
offering that includes a BMS would do well to tell
all . . . inquiring pilots NEED to know.
And as a pilot I want to know about temperatures. When used well
(correct voltages and currents within limits, no recharging ever
after full discharge) the remaining danger is a manufacturing fault,
with temperature discrepancy the only available signal.
And a measure of top balancing is needed unless we are willing to
adopt a discipline of doing that externally. A certain minimum
balancing current per Ah, say 50mA or so is required. I've seen
balancing currents quoted for Chinese BMS products that are likely
useless for any realistic battery size (they may be intended for UPS
batteries - very long charging times and smallish charging currents).
Exactly. An these issues drive cost of ownership. Yes,
the lithium products have stellar performance in some
venues but with LIMITS that much be UNDERSTOOD and
incorporated into the user's operating philosophy.
$time$ fiddling with batteries is $time$ not available
to go flying.
And the balancing algorithm is often primitive - most balancers only
balance at the very end of the charging process by comparing a cell
voltage with a high limit-voltage, not during the charging process by
comparing a cell voltage with the voltages of other cells. The latter
allows good balancing with a lower alternator set voltage. In
exchange for a few percent of charge you get much longer life - apparently.
"Apparently" is the operative term. The family
of lithium cells available for incorporation into
finished goods is not large . . . There's probably
no more than a half dozen shakers-n-movers in
the cylindrical cell market. They're all pretty
big names . . . I doubt that core capabilities
of the range of offerings varies much. But we
see a large variation in proposed operating
philosophies across the spectrum of "assemblers"
who package these cells up for market.
I wish you wisdom with the 4th article on batteries (great articles
so far, I approve of the current editor in chief of KP!)
Thank you my friend. I'm learning. But I wish that the
questions were being answered faster than they surface!
This first past at lithium-for-airplanes will probably
be disappointing for many who hope that a an ideal
drop-in-replacement for SVRLA is going to emerge.
But as you've noted, no matter what the advertising
hype says, "Their ain't no such thing as a lithium
drop-in for lead-acid."
For anything beyond the day-vfr machine with
gravity flow fuel and magnetos, the prudent
owner/pilot would do well to understand the
limitations. Further, assuming a willingness to
$invest$ in weight savings know that changes to
ownership and operating philosophy are inevitable.
Thank you for contributing to the dialog . . .
Bob . . .
________________________________________________________________________________
Subject: | Simple Diode Tester |
From: | "Eric M. Jones" <emjones(at)charter.net> |
Simple Diode Tester.
Here is a simple diode tester you may find useful:
http://www.energpolarit.com/docs/muscletest_withdirect.pdf
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421409#421409
________________________________________________________________________________
Subject: | Re: Simple Diode Tester |
From: | "Jeff B." <loboflyer(at)gmail.com> |
Just think! If you apply this to anything experiencing interference on your
airplane, you can solve the problem! If you apply it to your airplane it
might become invisible to radar!
So, how hard do we tap to wake the electrical system up?
-Jeff-
On Mon, Mar 31, 2014 at 6:59 PM, Eric M. Jones wrote:
> emjones(at)charter.net>
>
> Simple Diode Tester.
>
> Here is a simple diode tester you may find useful:
>
> http://www.energpolarit.com/docs/muscletest_withdirect.pdf
>
> --------
> Eric M. Jones
> www.PerihelionDesign.com
> 113 Brentwood Drive
> Southbridge, MA 01550
> (508) 764-2072
> emjones(at)charter.net
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=421409#421409
>
>
________________________________________________________________________________
From: | Jan de Jong <jan_de_jong(at)casema.nl> |
Subject: | Re: DIY CBOVM: variations on a theme |
> What I have seen is not very compatible with aircraft use. We do not
> want OV cut-out built-in (should be done somewhere up in the charging
> path).
>
> This is certainly the legacy philosophy for lead-acid
> and/or Ni-Cad batteries wherein the battery was a
> 'current sink' of demonstrable value for managing
> a runaway generator/alternator.
>
> But let's assume for the moment that one of our
> future design goals is to craft and prove airworthiness
> of an alternator-only operation protocol. Now we need
> to show that the runaway alternator can be controlled
> within the DO160/MilSTD704 envelope.
>
> If that proves to be practical, then the electronics
> in the battery need not assume any duties beyond those
> for protecting the battery . . . the battery MIGHT be
> relieved of duty for standing guard at the gates
> standing off runaway alternators.
The current lead-acid battery has 2 tasks when an OV event occurs:
1. slowing the event down to facilitate OVP without false triggering
2. keeping the battery-connected busses powered when the charging
system responsible for the OV event is disconnected from the bus
Both tasks must be covered or made unnecessary with any new alternative
use of a battery.
Jan de Jong
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Photo needed |
Got the picture I needed for the present task . . .
thanks to all who helped out.
Also received some pictures that I think are good
candidates for the cover of R13. I'll be archiving
these for future reference. As the reprint date
grows near, I'll be asking for any additional
submissions. The List members voted on the
most suitable image for R12 . . . I'm inclined
to do the same for R13.
Bob . . .
________________________________________________________________________________
Subject: | Icom A210 Low Headset Feedback once engine starts |
From: | "Nik" <nikpotter(at)web.de> |
Hello,
I installed the Icom A210 into my Rebel and it tests out fine on all parameters...except
when the engine starts! The RX volume is too low to hear regardless
of how high I set the Headset volume or play with the squelch. I have tried
various headsets to eliminate that the problem lies with my ANR headsets. I have
gone back through and tested all wires and proofed that the magnetos are properly
ground. From the very low volume I can ascertain no noise/hash so I don't
think the issue is suppressors or other interference. My system does not
have a noise suppressor on the alternator, but as I said, I'm not hearing any
interference.
I suspect that the radio is picking up on the cabin noise and canceling out the
sound - no idea.
Any suggestions greatly appreciated.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421526#421526
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Icom A210 Low Headset Feedback once engine starts |
At 04:41 AM 4/3/2014, you wrote:
>
>Hello,
>I installed the Icom A210 into my Rebel and it tests out fine on all
>parameters...except when the engine starts! The RX volume is too
>low to hear regardless of how high I set the Headset volume or play
>with the squelch. I have tried various headsets to eliminate that
>the problem lies with my ANR headsets. I have gone back through and
>tested all wires and proofed that the magnetos are properly
>ground. From the very low volume I can ascertain no noise/hash so I
>don't think the issue is suppressors or other interference.
Let's make sure I understand. While operating battery
only, engine off, volume is normal . . . in fact, you
can turn it up so far that it's uncomfortably loud?
>My system does not have a noise suppressor on the alternator, but as
>I said, I'm not hearing any interference.
Did you try operating the radio with engine running
but with alternator turned off?
>I suspect that the radio is picking up on the cabin noise and
>canceling out the sound - no idea.
>Any suggestions greatly appreciated.
That radio doesn't have anything you might
call a 'smart audio system'. Try listening
with the headset microphone unplugged . . . i.e.
headphones only to see if that makes a difference.
Except for received signal volume, does the "squelch
test function" seem to work? In other words, opening
the squelch under any engine operating condition produce
the normal 'dead air' hiss from the receiver? . . .
and it simply becomes lower volume after the engine
is running?
Bob . . .
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
=0A=0AI flew w/ a friend recently and when trying to get awos for our desti
nation airport (which is a pretty weak signal) it was almost impossible to
hear due to magneto noise.- The radio is a Garmin 430W in a Cherokee and
we were around 10 miles from the airport.- When we got within 3 or 4 mile
s the signal was much clearer.- All other transmissions with ATC & towers
were acceptable but I noticed at high volume I could clearly hear magneto
noise in the background.=0A=0A=0AI'm wondering if that's just the way it is
or if there is a problem with the magnetos or P lead wiring.=0A=0A=0AThere
must be one of Bob's handy-dandy write-ups on this topic but a quick searc
h of AeroElectric.com was in vain.=0A=0ACan someone point me in the right d
irection?=0A=0ATIA,=0A=0A-Jeff=0A
________________________________________________________________________________
From: | Tim Andres <tim2542(at)sbcglobal.net> |
Subject: | Re: Magneto Noise |
Not normal. Does it go away when you switch either mag off? YOu sure its a
mag?=0ATim=0A=0A=0A=0A=0A________________________________=0A From: Jeff Luc
key =0ATo: "aeroelectric-list(at)matronics.com" =0ASent: Sunday, April 6, 2014 10:04 AM=0ASubject:
AeroElectric-List: Magneto Noise=0A =0A=0A=0A=0A=0AI flew w/ a friend rece
ntly and when trying to get awos for our destination airport (which is a pr
etty weak signal) it was almost impossible to hear due to magneto noise.-
The radio is a Garmin 430W in a Cherokee and we were around 10 miles from
the airport.- When we got within 3 or 4 miles the signal was much clearer
.- All other transmissions with ATC & towers were acceptable but I notice
d at high volume I could clearly hear magneto noise in the background.=0A
=0A=0AI'm wondering if that's just the way it is or if there is a problem w
ith the magnetos or P lead wiring.=0A=0A=0AThere must be one of Bob's handy
-dandy write-ups on this topic but a quick search of AeroElectric.com was i
n vain.=0A=0ACan someone point me in the right direction?=0A=0ATIA,=0A=0A-J
====================
________________________________________________________________________________
From: | "David Lloyd" <skywagon(at)charter.net> |
Subject: | Re: Magneto Noise |
I would suspect the "shield" part of the P-lead cable has broken and is
no longer grounded at the mag. housing. 2nd, a small chance that the
heavy grounding cable from the engine to aircraft frame is missing or
not making a full connection due to corrosion or other flaw.
Dave
-------------------------------------------------------------------------
-------
----- Original Message -----
From: Tim Andres
To: aeroelectric-list(at)matronics.com
Sent: Sunday, April 06, 2014 12:13 PM
Subject: Re: AeroElectric-List: Magneto Noise
Not normal. Does it go away when you switch either mag off? YOu sure
its a mag?
Tim
-------------------------------------------------------------------------
-----
From: Jeff Luckey <jluckey(at)pacbell.net>
To: "aeroelectric-list(at)matronics.com"
Sent: Sunday, April 6, 2014 10:04 AM
Subject: AeroElectric-List: Magneto Noise
I flew w/ a friend recently and when trying to get awos for our
destination airport (which is a pretty weak signal) it was almost
impossible to hear due to magneto noise. The radio is a Garmin 430W in
a Cherokee and we were around 10 miles from the airport. When we got
within 3 or 4 miles the signal was much clearer. All other
transmissions with ATC & towers were acceptable but I noticed at high
volume I could clearly hear magneto noise in the background.
I'm wondering if that's just the way it is or if there is a problem
with the magnetos or P lead wiring.
There must be one of Bob's handy-dandy write-ups on this topic but a
quick search of AeroElectric.com was in vain.
Can someone point me in the right direction?
TIA,
-Jeff
http://www.matronics.com/Navigator?AeroElectri"
href="http://forums.matronics.com/">http://forums.matronics.com
_="nofollow" target="_blank"
href="http://www.matronics.com/contributi=
________________________________________________________________________________
From: | "mick muller" <mmul6471(at)bigpond.net.au> |
Subject: | RE: AeroElectric-List Digest: 3 Msgs - 04/06/14 |
WE had a similar problem with noise, and the issue turned out to be the
Condensers in the Magneto.
This was despite the Mag having been overhauled about 170 hours prior to
that.
Mick
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
AeroElectric-List Digest Server
Sent: Monday, 7 April 2014 4:58 PM
Subject: AeroElectric-List Digest: 3 Msgs - 04/06/14
*
=================================================
Online Versions of Today's List Digest Archive
=================================================
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AeroElectric-List Digest Archive
---
Total Messages Posted Sun 04/06/14: 3
----------------------------------------------------------
Today's Message Index:
----------------------
1. 10:05 AM - Magneto Noise (Jeff Luckey)
2. 12:14 PM - Re: Magneto Noise (Tim Andres)
3. 01:01 PM - Re: Magneto Noise (David Lloyd)
________________________________ Message 1
_____________________________________
From: Jeff Luckey <jluckey(at)pacbell.net>
Subject: AeroElectric-List: Magneto Noise
=0A=0AI flew w/ a friend recently and when trying to get awos for our desti
nation airport (which is a pretty weak signal) it was almost impossible to
hear due to magneto noise.- The radio is a Garmin 430W in a Cherokee and we
were around 10 miles from the airport.- When we got within 3 or 4 mile s the
signal was much clearer.- All other transmissions with ATC & towers were
acceptable but I noticed at high volume I could clearly hear magneto noise
in the background.=0A=0A=0AI'm wondering if that's just the way it is or if
there is a problem with the magnetos or P lead wiring.=0A=0A=0AThere must
be one of Bob's handy-dandy write-ups on this topic but a quick searc h of
AeroElectric.com was in vain.=0A=0ACan someone point me in the right d
irection?=0A=0ATIA,=0A=0A-Jeff=0A
________________________________ Message 2
_____________________________________
From: Tim Andres <tim2542(at)sbcglobal.net>
Subject: Re: AeroElectric-List: Magneto Noise
Not normal. Does it go away when you switch either mag off? YOu sure its a
mag?=0ATim=0A=0A=0A=0A=0A________________________________=0A From: Jeff Luc
key =0ATo: "aeroelectric-list(at)matronics.com" =0ASent: Sunday, April 6, 2014 10:04 AM=0ASubject:
AeroElectric-List: Magneto Noise=0A =0A=0A=0A=0A=0AI flew w/ a friend rece
ntly and when trying to get awos for our destination airport (which is a pr
etty weak signal) it was almost impossible to hear due to magneto noise.-
The radio is a Garmin 430W in a Cherokee and we were around 10 miles from
the airport.- When we got within 3 or 4 miles the signal was much clearer
.- All other transmissions with ATC & towers were acceptable but I notice d
at high volume I could clearly hear magneto noise in the background.=0A
=0A=0AI'm wondering if that's just the way it is or if there is a problem w
ith the magnetos or P lead wiring.=0A=0A=0AThere must be one of Bob's handy
-dandy write-ups on this topic but a quick search of AeroElectric.com was i
n vain.=0A=0ACan someone point me in the right direction?=0A=0ATIA,=0A=0A-J
====================
________________________________ Message 3
_____________________________________
From: "David Lloyd" <skywagon(at)charter.net>
Subject: Re: AeroElectric-List: Magneto Noise
I would suspect the "shield" part of the P-lead cable has broken and is no
longer grounded at the mag. housing. 2nd, a small chance that the heavy
grounding cable from the engine to aircraft frame is missing or not making a
full connection due to corrosion or other flaw.
Dave
-------------------------------------------------------------------------
-------
----- Original Message -----
From: Tim Andres
To: aeroelectric-list(at)matronics.com
Sent: Sunday, April 06, 2014 12:13 PM
Subject: Re: AeroElectric-List: Magneto Noise
Not normal. Does it go away when you switch either mag off? YOu sure its a
mag?
Tim
-------------------------------------------------------------------------
-----
From: Jeff Luckey <jluckey(at)pacbell.net>
To: "aeroelectric-list(at)matronics.com"
Sent: Sunday, April 6, 2014 10:04 AM
Subject: AeroElectric-List: Magneto Noise
I flew w/ a friend recently and when trying to get awos for our
destination airport (which is a pretty weak signal) it was almost
impossible to hear due to magneto noise. The radio is a Garmin 430W in
a Cherokee and we were around 10 miles from the airport. When we got
within 3 or 4 miles the signal was much clearer. All other
transmissions with ATC & towers were acceptable but I noticed at high
volume I could clearly hear magneto noise in the background.
I'm wondering if that's just the way it is or if there is a problem
with the magnetos or P lead wiring.
There must be one of Bob's handy-dandy write-ups on this topic but a
quick search of AeroElectric.com was in vain.
Can someone point me in the right direction?
TIA,
-Jeff
http://www.matronics.com/Navigator?AeroElectri"
href="http://forums.matronics.com/">http://forums.matronics.com
_="nofollow" target="_blank"
href="http://www.matronics.com/contributi
-----
No virus found in this message.
Checked by AVG - www.avg.com
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Magneto Noise |
At 12:04 PM 4/6/2014, you wrote:
I flew w/ a friend recently and when trying to get awos for our
destination airport (which is a pretty weak signal) it was almost
impossible to hear due to magneto noise. The radio is a Garmin 430W
in a Cherokee and we were around 10 miles from the airport. When we
got within 3 or 4 miles the signal was much clearer. All other
transmissions with ATC & towers were acceptable but I noticed at high
volume I could clearly hear magneto noise in the background.
I'm wondering if that's just the way it is or if there is a problem
with the magnetos or P lead wiring.
Was this a new condition or has it been that
way 'forever'. It's difficult for the neophyte
observer to tell the difference between ignition
noises getting into the system by way of plug wire
radiation versus p-lead radiation.
First, make sure that the perceived noise goes up
and down with volume control settings on radio.
This all but guarantees that it's coming in through
the antenna.
Then, disconnect both p-leads from the back of the
magnetos and run the engine. See if the noise is
still heard . . . turn to unused frequency . . .
open squelch.
If you can still hear it, then look for bad plug
wire. If not, hook up one p-lead at a time and
repeat experiment . . . see if noise is predicated
on either or both of the p-leads being hooked up.
Once you've identified the offending radiator,
you need to figure out why. If this is a 'new'
condition, then you're looking for something that
has changed. Bad cap in mag (probably not both)
broken ground lead on p-lead shield. If possible/
practical wire p-lead wires per Figure Z-27
http://tinyurl.com/n3oy37f
Ground p-lead shields at magneto end only . . .
use p-lead shields to ground mag switch. Remove
and existing ground to the mag switch.
If the noise is coming from both p-leads,
there are 'approved' magneto noise filters
http://tinyurl.com/l3s4mrj
that most mechanics will install with a simple
log-book entry.
Bob . . .
Bob . . .
________________________________________________________________________________
From: | Thomas Blejwas <tomblejwas(at)yahoo.com> |
Subject: | When are diodes needed? |
In adapting Z-07 and/or Z-19, I'm confused about the use and purpose of dio
des.- As I understand them, diodes allow current to flow in one direction
, with a small voltage drop, but not in the opposite direction, except for
a small leakage.- The voltage drop times the forward current yields a pow
er loss that results in heat, which may need to be dissipated to keep the h
eat from damaging the diode or other nearby equipment.- The power lost ma
y also be an issue in a battery-only situation after loss of an alternator,
for example.- O.K. so far?=0A=0APairs of diodes are used in Z-19 for the
two battery feeds for the main fuel pump, for example.- When both feeds
are on, this would keep a "good" battery from feeding a "bad" one.- Is th
at the primary purpose?- In Z-07, only one feed to the bus with the fuel
pump has a diode because judicious switching can isolate either battery.-
Correct?- Is there something more that I'm missing?- For example, if I
'm not concerned about one battery "feeding" another, do I still need diode
s to "smooth" the feed to a bus from two different batteries?- Thanks.=0A
=0ATom=0A=0ASent from my iPad
________________________________________________________________________________
Subject: | Z13/8 Main Alternator. |
From: | "MikeDunlop" <mdunlop001(at)aol.com> |
I'm finishing off my electrical system in a Long-EZ that includes the SD-8, exactly
as per the Z13/8 and have to make a final choice of the main alternator.
For cost and availability locally I've decided to go with either a Lucas 60amp
or 70amp. The advice I'm seeking is regarding the regulator, these units have
an internal regulator, so do I keep the internal regulator? (remember the Z13/8
has the OV protection between the regulator and the bus) or do I do a conversion
to use a B&C external regulator (I have a spare one I could use).
I've read many, many threads on OV and runaway alternators etc. and am not too
sure if using the internal regulator in the Z13/8 architecture will give me complete
protection.
Regards
Mike Dunlop (UK)
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421821#421821
________________________________________________________________________________
Subject: | Re: When are diodes needed? |
From: | "user9253" <fransew(at)gmail.com> |
It is unlikely that a battery will be bad enough that the other "good" battery
would feed it. A more important reason for isolating the two fuel pump circuits
in Z-19 is to prevent alternator charging current from back-feeding through
small wires and fuses intended to carry only the fuel pump load.
There is more than one version of Z-07. Looking at revision 5, the diode in the
"Engine B" wire prevents engine starting current and main bus load current
from flowing through the "Engine B" wire from the Aux battery.
I do not know what you mean by diodes "smoothing" the feed.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421822#421822
________________________________________________________________________________
Subject: | Re: noise problem on radio |
From: | Sacha <uuccio(at)gmail.com> |
I'm back trying to look for a solution to my noise problem on the radio. The original
thread was started in Feb so for those who missed it, the installation
is a Rotax 912UL on a Kitfox with a Trio Avionics Propilot Autopilot, a GNS430
and a GMA240 audio panel. The mag leads are unshielded. I think is a NEW problem,
as the first few hours of flying this installation did not seem to present
this problem. I say I think because I'm not 100% sure here because I don't
think I turned the a/p on during the first few flights (it was a year ago).
The noise appears in the form of an RX signal in the GNS430, and is correlated
to two things:
- the a/p box being on (not necessarily the servos though)
- the engine RPM being above 3800 RPM
Specifically, when the a/p is off, I never hear any noise. And when the a/p is
on and the RPM is below 3500 (e.g. in a descent) the noise can be squelched off
by the audio panel (though the radio still shows an RX signal). But if I'm
in a climb and have the a/p on then the only way I can get rid of the noise is
by turning the volume of the audio panel right down (the volume of the GNS430
radio does not affect the loudness of the noise).
I have tried to turn up the squelch on the GNS430 but I'm not sure I'm doing it
right. I press the volume button once and then turn it, but it doesn't appear
that the pressing the button makes any difference. Am I doing something wrong
there?
Below are the answers to some of Bob N's previous suggestions.
> On 27 Feb 2014, at 15:15, "Robert L. Nuckolls, III"
wrote:
>
>
>
> No, I haven't. Is it worth getting my hands on an SWR meter?
>
> If your shield ground is loose at the radio, it can open a
> pathway for conducting otherwise insignificant
> signals into the receiver.
>
> If you don't have ready access to one, hold off acquiring
> it. But check the mechanical integrity of your coax
> connections at the back of the radio. How well does the
> comm transceiver work? Have you detected any shortfall
> in performance?
>
The coax connections look ok mechanically. And the com transceiver appears to work
fine, although I haven't tried it over longer distances.
>
> http://www.trioavionics.com/Pro%20Pilot%20Manual%203.8.pdf
>
> Okay . . . that's a busy little box. Refresh my
> memory, is this noise a new thing or has it always
> been present. Also, when receiving a weak signal
> (tune in an ATIS and fly away from airport until
> signal starts to get noisy . . . then turn a/p
> on/off and judge how much effect the a/p noise
> has on reception of weak signals).
I'll try that next time I can get an ATIS (I am 60 miles from the nearest ATIS
and not in theory allowed to fly more than 500 feet above the nearest obstacle
in a 3 mile radius, so it's quite difficult to get reception).
>
> I sniffed around yesterday with the handheld and its regular antenna. What
> I noticed was that as soon as I switch on the Avionics and the handheld
> antenna is close to them, I hear a bunch of noise, but I guess that's
> normal. When I switch on the AP and move the handheld antenna close to the
> servo cables (that are shielded), I can hear a stronger kind of buzzing
> noise. I really have to be almost touching those shielded cables though in
> order to pick anything up. I didn't try putting the antenna close to the
> radio's COM coax connector though.
>
> You wont see any noise coming OUT of this junction,
> but it is a potential point of ingress for noises
> that tend to pile up behind the panel.
>
> Do you have any pictures of how to build these? Is this
> http://www.emcesd.com/tt120100.htm the right idea?
>
> Yes! good find. I got a little ahead of myself
> in sifting the simple ideas. Don't run off and build
> one (or e-field probe) yet.
>
> It's not clear to me yet as to operational significance
> of the noise. DO-160 ALLOWS certain levels of noise
> while putting potential victims ON NOTICE that such
> noises may be present but normally insignificant.
>
> My sense of the situation from your narrative
> so far is that while the A/P is a noteworthy
> contributor . . . it's not the sole potential
> antagonist . . . we may discover that it is
> within practical limits and you just need to
> tighten the squelch on the receiver a tad.
I tried (see above) but not sure I'm doing it right.
>
> I think I've related my experiences with the
> symphony of noises that are often heard in
> various systems while sitting on the ground
> with engines off and wearing headphones . . .
> noises that are completely insignificant
> while in flight.
>
> Let's size the task before we get out hammers-
> n-saws.
>
> Bob . . .
>
Sacha
________________________________________________________________________________
From: | Thomas Blejwas <tomblejwas(at)yahoo.com> |
Subject: | Re: When are diodes needed? |
Thanks Joe,=0A=0AI now understand the potential problem with feeding throug
h small wires and fuses.- Embarrassed that I missed it. -"Smoothing" wa
s not really what I should have said.- I have been told that, when two su
pplies-through diodes are connected to a-component, the diodes ensure t
hat the one with the higher voltage supplies the current.- As the voltage
in-that one drops, the transition to the other is seamless.- True?-
-Without the diodes, I have two batteries in parallel,-which yields an
average voltage, assuming similar internal resistances.- Not clear to me
the advantage of one over the other.- =0A=0AThanks again for your help.
-=0A=0ATom=0A=0A=0A=0A-=0A=0A=0A>________________________________=0A> F
rom: user9253 =0A>To: aeroelectric-list(at)matronics.com
=0A>Sent: Wednesday, April 9, 2014 8:54 AM=0A>Subject: AeroElectric-List: R
e: When are diodes needed?=0A> =0A>=0A>--> AeroElectric-List message poste
d by: "user9253" =0A>=0A>It is unlikely that a battery w
ill be bad enough that the other "good" battery would feed it.- A more im
portant reason for isolating the two fuel pump circuits in Z-19 is to preve
nt alternator charging current from back-feeding through small wires and fu
ses intended to carry only the fuel pump load.=0A>There is more than one ve
rsion of Z-07.- Looking at revision 5, the diode in the "Engine B" wire p
revents engine starting current and main bus load current from flowing thro
ugh the "Engine B" wire from the Aux battery.=0A>- I do not know what you
mean by diodes "smoothing" the feed.=0A>Joe=0A>=0A>--------=0A>Joe Gores
=0A>=0A>=0A>=0A>=0A>Read this topic online here:=0A>=0A>http://forums.matro
=========================0A
=========================0A
=========================0A
>=0A>=0A>=0A>=0A>=0A>
________________________________________________________________________________
Subject: | Re: Z13/8 Main Alternator. |
From: | Bill Allen <billallensworld(at)gmail.com> |
Hi Mike,
So you're nearly finished? Will you be flying this year?
If you come past in May/June Gary Hertzler will be here again for more Ez
talk :^)
Bill
On 9 April 2014 15:44, MikeDunlop wrote:
>
> I'm finishing off my electrical system in a Long-EZ that includes the
> SD-8, exactly as per the Z13/8 and have to make a final choice of the main
> alternator.
>
> For cost and availability locally I've decided to go with either a Lucas
> 60amp or 70amp. The advice I'm seeking is regarding the regulator, these
> units have an internal regulator, so do I keep the internal regulator?
> (remember the Z13/8 has the OV protection between the regulator and the
> bus) or do I do a conversion to use a B&C external regulator (I have a
> spare one I could use).
>
> I've read many, many threads on OV and runaway alternators etc. and am not
> too sure if using the internal regulator in the Z13/8 architecture will
> give me complete protection.
>
> Regards
>
> Mike Dunlop (UK)
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=421821#421821
>
>
________________________________________________________________________________
Subject: | Re: When are diodes needed? |
From: | "user9253" <fransew(at)gmail.com> |
It is true that a load will draw current from whichever source has the higher voltage.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421830#421830
________________________________________________________________________________
Subject: | EI MVP-50 on E Bay |
From: | John McMahon <blackoaks(at)gmail.com> |
Just saw this for sale new & unopened unit on E Bay under Avionics and it
is closing soon; if interested the link is:
http://www.ebay.com/itm/141240683303?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
EI MVP-50 6 Cylinder Experimental Aircraft Engine Monitor
--
John McMahon
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Z13/8 Main Alternator. |
At 09:44 AM 4/9/2014, you wrote:
>
>I'm finishing off my electrical system in a Long-EZ that includes
>the SD-8, exactly as per the Z13/8 and have to make a final choice
>of the main alternator.
>
>For cost and availability locally I've decided to go with either a
>Lucas 60amp or 70amp. The advice I'm seeking is regarding the
>regulator, these units have an internal regulator, so do I keep the
>internal regulator? (remember the Z13/8 has the OV protection
>between the regulator and the bus) or do I do a conversion to use a
>B&C external regulator (I have a spare one I could use).
>
>I've read many, many threads on OV and runaway alternators etc. and
>am not too sure if using the internal regulator in the Z13/8
>architecture will give me complete protection.
Alternators with built in regulators . . . as a GENERAL
rule, DO NOT feature ov protection consistent
with legacy design goals. One exception I'm aware of
is PlanePower who appears to be using a customized
built-in regulator with crowbar ov protection and
positive crew-controlled power to the field.
At the time of this writing, it's the ONLY alternator
offering that conforms to the legacy alternator control/
ov protection philosophy.
I'm not sure if I understand your question . . . The
SD-8 should be installed as shown in the drawing.
Further, its ov protection, control and regulation
is entirely independent of any choices you make for
a main alternator.
If you're contemplating an over-the-counter automotive
alternator with built in regulator . . . it will
PROBABLY perform as advertised. But it will not conform
to the design goals adopted by all TC aircraft and the
majority of OBAM aircraft.
If you have a B&C alternator controller laying around,
it's generally not difficult to modify any stock automotive
machine to accept EXTERNAL power, regulation, and protection.
If you're not up to the task of doing the mod, a local
alternator repair shop may be willing/able to do it
for you.
Bob . . .
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Subject: | Re: When are diodes needed? |
Joe,=0ANot sure how to answer without a little more context.- Can you giv
e us a sketch of the circuit in question?=0A=0AIn the mean time, maybe this
will help:=0A=0ACrude diode symbol: - ->|=0A=0A=0A=0ACurrent will flow t
hru the diode (left to right) in the following circuit:=0A=0A5 volts --
--- --- - 4 volts=0A=0A---------- ->| ------------=0A=0A=0AC
urrent will NOT flow backward (right to left) thru the diode in the followi
ng circuit:=0A=0A4 volts -- --- --- - 5 volts=0A=0A------
---- ->| ------------=0A=0AThe diode acts as a "check-valve" and prevents c
urrent from flowing backwards=0A=0A=0AHope this helps=0A=0A-Jeff=0A=0A=0A__
______________________________=0A From: user9253 <fransew(at)gmail.com>=0ATo:
aeroelectric-list(at)matronics.com =0ASent: Wednesday, April 9, 2014 11:18 AM
=0ASubject: AeroElectric-List: Re: When are diodes needed?=0A =0A=0A--> Aer
oElectric-List message posted by: "user9253" =0A=0AIt is
true that a load will draw current from whichever source has the higher vo
ltage.=0AJoe=0A=0A--------=0AJoe Gores=0A=0A=0A=0A=0ARead this topic online
here:=0A=0Ahttp://forums.matronics.com/viewtopic.php?p=421830#421830=0A
=
________________________________________________________________________________
Subject: | Re: Z13/8 Main Alternator. |
From: | "MikeDunlop" <mdunlop001(at)aol.com> |
Bill,
Nice to hear from you again, I've called by your hangar a few times but missed
you.
Yes I'm hoping to get things wrapped up soon and start the testing phase.
I will definitely like to meet Gary again and talk EZ, I picked up some very useful
information last time that made me change the cowling air intake design
and the prop attachment method.
Regards
Mike
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421841#421841
________________________________________________________________________________
Subject: | Re: Z13/8 Main Alternator. |
From: | "MikeDunlop" <mdunlop001(at)aol.com> |
Bob,
Thanks very much for the information. I will modify the alternator and use the
B&C regulator.
The SD-8 is installed exactly as per Z13/8, totally independent of the main alternator.
Regards
Mike (UK)
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421843#421843
________________________________________________________________________________
From: | Bob McCallum <robert.mccallum2(at)sympatico.ca> |
Subject: | Re: When are diodes needed? |
Yes.
All else being equal if you connect both a 12V and a 6V source in parallel
to a single load without any other intervening components then the 12V sour
ce will supply the load and the 6V source will sit idly by doing nothing.
Bob McC
> Subject: AeroElectric-List: Re: When are diodes needed?
> From: fransew(at)gmail.com
> Date: Wed=2C 9 Apr 2014 11:18:58 -0700
> To: aeroelectric-list(at)matronics.com
>
>
> It is true that a load will draw current from whichever source has the hi
gher voltage.
> Joe
>
> --------
> Joe Gores
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=421830#421830
>
>
>
>
>
>
>
===========
===========
===========
===========
>
>
>
________________________________________________________________________________
Subject: | Re: When are diodes needed? |
From: | Bob Verwey <bob.verwey(at)gmail.com> |
Is there a practical application for this?
On 09/04/2014, Bob McCallum wrote:
> Yes.
>
> All else being equal if you connect both a 12V and a 6V source in parallel
> to a single load without any other intervening components then the 12V
> source will supply the load and the 6V source will sit idly by doing
> nothing.
>
> Bob McC
>
>> Subject: AeroElectric-List: Re: When are diodes needed?
>> From: fransew(at)gmail.com
>> Date: Wed, 9 Apr 2014 11:18:58 -0700
>> To: aeroelectric-list(at)matronics.com
>>
>>
>> It is true that a load will draw current from whichever source has the
>> higher voltage.
>> Joe
>>
>> --------
>> Joe Gores
>>
>>
>>
>>
>> Read this topic online here:
>>
>> http://forums.matronics.com/viewtopic.php?p=421830#421830
>>
>>
>>
>>
>>
>>
>>
> ===========
> ===========
> ===========
> ===========
>>
>>
>>
>
--
Best...
Bob Verwey
________________________________________________________________________________
From: | "William Schertz" <wschertz(at)comcast.net> |
Subject: | Re: When are diodes needed? |
I believe that the 12V source will try to charge the 6V source,
overcharging the 6V battery if a diode is not present.
From: Bob McCallum
Sent: Wednesday, April 09, 2014 3:37 PM
Subject: RE: AeroElectric-List: Re: When are diodes needed?
Yes.
All else being equal if you connect both a 12V and a 6V source in
parallel to a single load without any other intervening components then
the 12V source will supply the load and the 6V source will sit idly by
doing nothing.
Bob McC
> Subject: AeroElectric-List: Re: When are diodes needed?
> From: fransew(at)gmail.com
> Date: Wed, 9 Apr 2014 11:18:58 -0700
> To: aeroelectric-list(at)matronics.com
>
>
> It is true that a load will draw current from whichever source has the
higher voltage.
> Joe
>
> --------
> Joe Gores
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=421830#421830
>
>
>
> Archive Search & Download, 7-Day Browse, Chat, FAQ,
> --> http://www.matronics.com/Navigator?AeroElectric-List
>
=======================
>
>
>
________________________________________________________________________________
From: | Bob McCallum <robert.mccallum2(at)sympatico.ca> |
Subject: | Re: When are diodes needed? |
Yes absolutely ! (assuming the sources are batteries. If they are diode iso
lated power supplies (alternators) the original statement stands)
I wasn't suggesting that this was a practical thing to do. Mearly that the
higher voltage source will supply the load. Normally we would be talking pa
ralleled batteries or a battery and an alternator. In either case the highe
r voltage source will supply the load. All else being equal=2C the lower vo
ltage source will be idle until the system voltage sags to equal the lower.
(even this is an oversimplification=2C but hopefully gets the idea across.
The higher of two paralleled differing voltages will be supplying the load
s=2C including attempting to raise the lower voltage source. That's the bas
is of how a charging system works)
Bob McC
From: wschertz(at)comcast.net
Subject: Re: AeroElectric-List: Re: When are diodes needed?
Date: Thu=2C 10 Apr 2014 07:12:02 -0500
=0A
=0A
=0A
=0A
=0A
=0A
I believe that the 12V source will try to charge the 6V source=2C =0A
overcharging the 6V battery if a diode is not present.=0A
=0A
=0A
=0A
=0A
From: Bob McCallum =0A
Sent: Wednesday=2C April 09=2C 2014 3:37 PM=0A
=0A
Subject: RE: AeroElectric-List: Re: When are diodes =0A
needed?=0A
=0A
=0A
Yes.
All else being =0A
equal if you connect both a 12V and a 6V source in parallel to a =0A
single load without any other intervening components then the 12V source wi
ll =0A
supply the load and the 6V source will sit idly by doing nothing.
Bob =0A
McC
=0A
> Subject: AeroElectric-List: Re: When are diodes needed?
> From: =0A
fransew(at)gmail.com
> Date: Wed=2C 9 Apr 2014 11:18:58 -0700
> To: =0A
aeroelectric-list(at)matronics.com
>
> --> AeroElectric-List =0A
message posted by: "user9253"
>
> It is =0A
true that a load will draw current from whichever source has the higher =0A
voltage.
> Joe
>
> --------
> Joe Gores
> =0A
>
>
>
> Read this topic online here:
> =0A
> http://forums.matronics.com/viewtopic.php?p=421830#421830
> =0A
>
>
> Archive Search & Download=2C 7-Day Browse=2C Chat=2C =0A
FAQ=2C
> --> http://www.matronics.com/Navigator?AeroElectric-List
> =0A
=======================
>
>
>
=0A
=0A
href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.ma
tronics.com/Navigator?AeroElectric-List=0A
href="http://forums.matronics.com">http://forums.matronics.com=0A
href="http://www.matronics.com/contribution">http://www.matronics.com/c
=0A
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________________________________________________________________________________
Subject: | Re: Z13/8 Main Alternator. |
From: | Bill Allen <billallensworld(at)gmail.com> |
Yes, I was away Jan/Feb.
I'll be back here much more after Easter as Gary will be here then, so
May/June would be a good time - call or text me?
Bill
On 9 April 2014 21:22, MikeDunlop wrote:
>
> Bill,
>
> Nice to hear from you again, I've called by your hangar a few times but
> missed you.
>
> Yes I'm hoping to get things wrapped up soon and start the testing phase.
>
> I will definitely like to meet Gary again and talk EZ, I picked up some
> very useful information last time that made me change the cowling air
> intake design and the prop attachment method.
>
> Regards
>
> Mike
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=421841#421841
>
>
________________________________________________________________________________
Subject: | Re: EarthX lithium |
From: | "user9253" <fransew(at)gmail.com> |
There was a recent comparison of a LiFePo battery versus Lead Acid and the test
results posted in a graph on VansAirforce.
http://www.vansairforce.com/community/showthread.php?t=111788
It seems that the actual Amp Hour rating of the LiFePo is only half of the advertised
rating. Even so, a 36 amp hour LiFePo provides almost the same endurance
as a PC680 at less than half of the weight. The author intends to install
the LiFePo in his RV-8A. It will be interesting to see if he is satisfied with
this battery a few years from now.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=421907#421907
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: EarthX lithium |
At 06:45 AM 4/11/2014, you wrote:
>
>There was a recent comparison of a LiFePo battery versus Lead Acid
>and the test results posted in a graph on VansAirforce.
>http://www.vansairforce.com/community/showthread.php?t=111788
>It seems that the actual Amp Hour rating of the LiFePo is only half
>of the advertised rating. Even so, a 36 amp hour LiFePo provides
>almost the same endurance as a PC680 at less than half of the
>weight. The author intends to install the LiFePo in his RV-8A. It
>will be interesting to see if he is satisfied with this battery a
>few years from now.
I missed getting the 4th slot filled on time in
the series of articles on batteries for Kitplanes.
Spent an extra month attempting to engage a number
of suppliers/manufacturers in technical conversations
about their products.
Only one has been eagerly forthcoming (EarthX) and
one other begrudgingly offered tid-bits of the
requested data.
I've offered to work with EarthX to wordsmith
specification and sales literature that would
get them more than a casual glance and fewer
snickers from a TC airframer.
Part IV of the battery articles has been submitted
to Paul Dye. I've discovered a lot about the current
state of LiPo offerings but my inquiries have generated
more questions than answers!
As the thread cited above demonstrates, there's
a good bit yet to be learned about the lithium
battery industry. Encourage folks on the
VansAirForce-list to join us here on the AeroElectric-
List as well.
By the way, that PbEq (lead-acid equivalency) thingy
is pure marketing hype. It speaks to battery impedance
and ability to crank engines . . . says NOTHING about
energy available for battery-only ops.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Schumacher XC75W charger |
I've been doing some tests on a 100Ah rated (20 hr rate)
battery that uses carbon foam for one of the grids. Ostensibly
lighter that a battery with both grids of lead.
http://tinyurl.com/q5hu266
Needed a robust charger for getting this puppy re-charged.
At the same time, I was interested in evaluating one of Schumacher's
current offerings in programmed chargers.
Bought a XC75W with nice buttons, annunciators and digital
display. Max charge rate was advertised as 20A. The first
time I plotted a recharge in the "AGM" mode, the charger
wanted to top-off charge at well over 15 volts. It had
barely leveled off at 15.7V when the microprocessor deemed the
battery charged!
The battery wheezed and whistled for a couple hours after
the charger shut down.
Emacs!
On the next cycle, I used the "GEL" mode. This mode tops off
at 14.4V . . . can't speak to ideal protocols for GEL batteries
but this looks like a good one for AGM as well. It's interesting
that it spent about as much time in top-off as it did for
charging.
Emacs!
Will learn more about this charger as testing progresses
on the battery. I may see if Schumacher's engineering staff
will comment on these findings . . . but in any case,
AGM mode in this charger is not recommended for any battery.
Watch this space . . .
Bob . . .
________________________________________________________________________________
From: | Matt Dralle <dralle(at)matronics.com> |
Subject: | Matronics Web Server Down for Repair (PLEASE READ)... |
Dear Listers,
Late Tuesday night 4/15/2014, the Matronics Web server crashed due to a multi-disk
RAID 5 failure. The system has complete data backups, but I will likely have
to order some replacement disks to rebuild the system. I'll work as quickly
as I can to restore the Matronics Web Server.
The Matronics EMAIL server is NOT impacted by this issue. All normal Matronics
Email List mail will flow as usual. However, the Matronics Web Forums interface
will not be available.
Also impacted by the Web Server outage will be the AeroElectric web site.
I will try to post daily updates on the Web Server restoration status.
I apologize for the inconvenience... :-(
Best regards,
Matt Dralle
Matronics Email List and Forum Admin.
Matt G Dralle | Matronics | 581 Jeannie Way | Livermore | CA | 94550
925-606-1001 V | 925-606-6281 F | dralle(at)matronics.com Email
http://www.matronics.com/ WWW | Featuring Products For Aircraft
________________________________________________________________________________
Subject: | Re: AeroElectric-List Digest: 1 Msgs - 04/16/14 |
From: | Eric Schlanser <eschlanser(at)yahoo.com> |
Not sure if this will go through what with the server outage and all, but today
I am integrating a diode into the aux alternator power 22 awg wire and I need
Bob's comic book on integrating homeless components. If someone hears this, please
respond.
Hope this works.
Eric
AeroElectric-List Digest Server wrote:
>*
>
> =================================================
> Online Versions of Today's List Digest Archive
> =================================================
>
>Today's complete AeroElectric-List Digest can also be found in either of the
>two Web Links listed below. The .html file includes the Digest formatted
>in HTML for viewing with a web browser and features Hyperlinked Indexes
>and Message Navigation. The .txt file includes the plain ASCII version
>of the AeroElectric-List Digest and can be viewed with a generic text editor
>such as Notepad or with a web browser.
>
>HTML Version:
>
> http://www.matronics.com/digest/digestview.php?Style=82701&View=html&Chapter 14-04-16&Archive=AeroElectric
>
>Text Version:
>
> http://www.matronics.com/digest/digestview.php?Style=82701&View=txt&Chapter 14-04-16&Archive=AeroElectric
>
>
> ===============================================
> EMail Version of Today's List Digest Archive
> ===============================================
>
>
> ----------------------------------------------------------
> AeroElectric-List Digest Archive
> ---
> Total Messages Posted Wed 04/16/14: 1
> ----------------------------------------------------------
>
>
>Today's Message Index:
>----------------------
>
> 1. 01:02 AM - Matronics Web Server Down for Repair (PLEASE READ)... (Matt
Dralle)
>
>
>
>________________________________ Message 1 _____________________________________
>
>
>From: Matt Dralle <dralle(at)matronics.com>
>Subject: AeroElectric-List: Matronics Web Server Down for Repair (PLEASE READ)...
>
>
>Dear Listers,
>
>Late Tuesday night 4/15/2014, the Matronics Web server crashed due to a multi-disk
>RAID 5 failure. The system has complete data backups, but I will likely have
>to order some replacement disks to rebuild the system. I'll work as quickly
>as I can to restore the Matronics Web Server.
>
>The Matronics EMAIL server is NOT impacted by this issue. All normal Matronics
>Email List mail will flow as usual. However, the Matronics Web Forums interface
>will not be available.
>
>Also impacted by the Web Server outage will be the AeroElectric web site.
>
>I will try to post daily updates on the Web Server restoration status.
>
>I apologize for the inconvenience... :-(
>
>Best regards,
>
>Matt Dralle
>Matronics Email List and Forum Admin.
>
>
>Matt G Dralle | Matronics | 581 Jeannie Way | Livermore | CA | 94550
>925-606-1001 V | 925-606-6281 F | dralle(at)matronics.com Email
>http://www.matronics.com/ WWW | Featuring Products For Aircraft
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: AeroElectric-List Digest: 1 Msgs - 04/16/14 |
At 09:06 AM 4/17/2014, you wrote:
>
>Not sure if this will go through what with the server outage and
>all, but today I am integrating a diode into the aux alternator
>power 22 awg wire and I need Bob's comic book on integrating
>homeless components. If someone hears this, please respond.
>Hope this works.
The list's are supported by separate hardware that
deals with e-mail so your posting is not going into
a black hole . . .
What kind of diode and where are you wanting to wire
it in and what purpose does it serve? If it's a little
plastic or glass wire lead diode then you can trim off
the diode leads to about 3/8", lap solder the wires to
each end and cover with a couple layers of heatshrink.
See attached . . .
Bob . . .
________________________________________________________________________________
From: | "Sacha" <uuccio(at)gmail.com> |
Subject: | AEC9001-1 Schottky Diode Assembly Instructions |
Along the same lines as Eric...
Could someone kindly post the assembly instructions for the AEC9001-1
Schottky Diode?
Regards,
Sacha
________________________________________________________________________________
From: | Eric Schlanser <eschlanser(at)yahoo.com> |
Subject: | Re: AeroElectric-List Digest: 1 Msgs - 04/16/14 |
To the AE_List\Bob,=0A=0AI found the comic book on integrating homeless com
ponents.-=0A=0AIn appreciation,=0A=0AEric=0A=0A=0A=0A____________________
____________=0A From: Eric Schlanser <eschlanser(at)yahoo.com>=0ATo: aeroelect
ric-list(at)matronics.com =0ASent: Thursday, April 17, 2014 10:06 AM=0ASubject
: Re: AeroElectric-List Digest: 1 Msgs - 04/16/14=0A =0A=0ANot sure if this
will go through what with the server outage and all, but today I am integr
ating a diode into the aux alternator power 22 awg wire and I need Bob's co
mic book on integrating homeless components. If someone hears this, please
respond.=0AHope this works.=0AEric =0A=0A=0A=0AAeroElectric-List Digest Ser
ver wrote:=0A=0A=0A*=0A=0A=====
=====================0A- Online
Versions of Today's List Digest Archive=0A===========
===============0A=0AToday's complete AeroElectr
ic-List Digest can also be found in either of the =0Atwo Web Links listed b
elow.- The .html file includes the Digest formatted =0Ain HTML for viewin
g with a web browser and features Hyperlinked Indexes =0Aand Message Naviga
tion.- The .txt file includes the plain ASCII version =0Aof the AeroElect
ric-List Digest and can be viewed with a generic text editor =0Asuch as Not
epad or with a web browser. =0A=0AHTML Version:=0A=0A- - http://www.mat
ronics.com/digest/digestview.php?Style=82701&View=html&Chapter 14-0
4-16&Archive=AeroElectric=0A=0AText Version:=0A=0A- - http://www.matr
onics.com/digest/digestview.php?Style=82701&View=txt&Chapter 14-04-
16&Archive=AeroElectric=0A=0A=0A=============
===========0A- EMail Version of Today's List Digest
Archive=0A=====================
===0A=0A=0A- - - - - ---------------------------------------
-------------------=0A- - - - - - - - - - - - -
AeroElectric-List Digest Archive=0A- - - - - - - - - -
- - - - - - - - - ---=0A- - - - - - - -
- - Total Messages Posted Wed 04/16/14: 1=0A- - - - - -----
-----------------------------------------------------=0A=0A=0AToday's Messa
ge Index:=0A----------------------=0A=0A- - 1. 01:02 AM - Matronics We
b Server Down for Repair (PLEASE READ)...- (Matt Dralle)=0A=0A=0A=0A_____
___________________________- Message 1- _______________________________
cs.com>=0ASubject: AeroElectric-List: Matronics Web Server Down for Repair
(PLEASE READ)...=0A=0A=0ADear Listers,=0A=0ALate Tuesday night 4/15/2014, t
he Matronics Web server crashed due to a multi-disk=0ARAID 5 failure.- Th
e system has complete data backups, but I will likely have=0Ato order some
replacement disks to rebuild the system.- I'll work as quickly=0Aas I can
to restore the Matronics Web Server.- =0A=0AThe Matronics EMAIL server i
s NOT impacted by this issue.- All normal Matronics=0AEmail List mail wil
l flow as usual.- However, the Matronics Web Forums interface=0Awill not
be available.=0A=0AAlso impacted by the Web Server outage will be the AeroE
lectric web site.=0A=0AI will try to post daily updates on the Web Server r
estoration status.=0A=0AI apologize for the inconvenience...- :-(=0A=0ABe
st regards,=0A=0AMatt Dralle=0AMatronics Email List and Forum Admin.=0A=0A
=0AMatt G Dralle | Matronics | 581 Jeannie Way | Livermore | CA | 94550=0A9
25-606-1001 V | 925-606-6281 F | dralle@matronics.com Email=0Ahttp://www.ma
===============
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: AEC9001-1 Schottky Diode Assembly Instructions |
At 10:38 AM 4/17/2014, you wrote:
>
>Along the same lines as Eric...
>Could someone kindly post the assembly instructions for the AEC9001-1
>Schottky Diode?
Here 'tis . . .
Bob . . .
________________________________________________________________________________
From: | Matt Dralle <dralle(at)matronics.com> |
Subject: | Matronics Web Server Repaired and ONLINE! (PLEASE READ) |
Dear Listers,
The new hard drives for the Matronics web server arrived today, Thursday 4/17/2014
and the RAID5 disk array rebuild went very smoothly.
Web server is back online and fully functional! No data or files were lost.
Additionally, those that frequent the AeroElectric web site will find that it has
been restored as well.
Best regards,
Matt Dralle
Matronics Email List and Forum Admin.
Matt G Dralle | Matronics | 581 Jeannie Way | Livermore | CA | 94550
925-606-1001 V | 925-606-6281 F | dralle(at)matronics.com Email
http://www.matronics.com/ WWW | Featuring Products For Aircraft
________________________________________________________________________________
Subject: | Re: AEC9001-1 Schottky Diode Assembly Instructions |
From: | "Eric M. Jones" <emjones(at)charter.net> |
Please let me Google that for you:
https://www.google.com/search?btnG=1&pws=0&q=AEC9001-1+Aeroelectric+Connection+
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422054#422054
________________________________________________________________________________
Subject: | Re: AEC9001-1 Schottky Diode Assembly Instructions |
From: | Sacha <uuccio(at)gmail.com> |
Thank you Bob.
Eric, I tried Google but the matronics site was down and (hard to believe but...)
that's the only place that particular document showed up in the Google search.
> On Apr 18, 2014, at 14:56, "Eric M. Jones" wrote:
>
>
> Please let me Google that for you:
>
> https://www.google.com/search?btnG=1&pws=0&q=AEC9001-1+Aeroelectric+Connection+
>
> --------
> Eric M. Jones
> www.PerihelionDesign.com
> 113 Brentwood Drive
> Southbridge, MA 01550
> (508) 764-2072
> emjones(at)charter.net
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=422054#422054
>
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
Subject: | Alternator selection for Rotax (a little off topic) |
From: | "rparigoris" <rparigor(at)suffolk.lib.ny.us> |
Hi Group
A little off topic so delete if you like.
I would like to install a more powerful alternator on my Rotax 914.
I have already selected a circuit breaker for the over-voltage crow bar, I was
wondering if anyone could recommend an alternator I could use that wouldn't exceed
the circuit breakers voltage and current rating? :
https://onedrive.live.com/redir?resid=550FC20DBDDB521D!3283&authkey=!AOJ6Dc5VV0v8uVo&v=3&ithint=photo%2c.JPG
Ron Parigoris
Sorry, I couldn't post this 18 days ago.
Insulators were (my best guess) more than 25 feet long, the main casting (gutted)
was a mere 30 tons!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422116#422116
________________________________________________________________________________
From: | rayj <raymondj(at)frontiernet.net> |
Subject: | Half failed LEDs |
I just removed about 8 blue LEDs from a string of lights that no longer
emitted light, but still have continuity. If any one wants them to
investigate, I'll mail them out.
--
Raymond Julian
Kettle River, MN
The things we admire in men, kindness and generosity, openness, honesty,
understanding and feeling are the concomitants of failure in our system.
And those traits we detest, sharpness, greed, acquisitiveness, meanness,
egotism and self-interest are the traits of success. And while men
admire the quality of the first they love the produce of the second.
-John Steinbeck, novelist, Nobel laureate (1902-1968)
________________________________________________________________________________
From: | "Sacha" <uuccio(at)gmail.com> |
Subject: | warning lights for engine T&Ps |
Aero-Electrics,
Is there an easy/robust way of incorporating "idiot" warning lights for the
engine T&Ps? When I first designed the panel I had in mind tri-colour LEDs
which would turn blue if a value was below normal, green if in the normal
range and red if above the normal range (e.g. for CHT temps or fuel
pressure).
I experimented with this circuit
https://www.spiyda.com/magento/index.php/three-colour-warning-light.html
which I used to measure the various senders resistances
but was not able to reliably calibrate the readings to get anything useful.
I am determined to do some bench tests to see whether I can make things work
better by incorporating a 12V voltage regulator upstream of the circuit to
get more repeatable readings. Before I embark on this though I thought I'd
check if there is already an established way of doing this?
Sacha
________________________________________________________________________________
Subject: | Re: warning lights for engine T&Ps |
From: | "Eric M. Jones" <emjones(at)charter.net> |
> Before I embark on this though I thought I'd
> check if there is already an established way of doing this?
> Sacha
Sacha,
There is a common op amp circuit called a "window discriminator" that is used to
do this. It is easy to set this up for many variable input voltages or currents.
National Semiconductor publishes online collections of op amp circuits which
is a good place to start.
ps When red and green are mixed, yellow is the visible result...although some color
deficient people might have an issue with this.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422234#422234
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Half failed LEDs |
At 07:09 AM 4/21/2014, you wrote:
>
>I just removed about 8 blue LEDs from a string of lights that no
>longer emitted light, but still have continuity. If any one wants
>them to investigate, I'll mail them out.
When you measure them with an ohmmeter, do they
show the same or similar resistance for either
polarity of the test leads?
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: warning lights for engine T&Ps |
>I am determined to do some bench tests to see whether I can make things work
>better by incorporating a 12V voltage regulator upstream of the circuit to
>get more repeatable readings. Before I embark on this though I thought I'd
>check if there is already an established way of doing this?
>Sacha
Good for you! Suggest you start by quantifying
the sensors. Most automotive sensors are of the
variable resistance type intended to drive
fairly low-sensitivity instruments . . . read
operating currents in the tens of milliamps.
My favorite approach is to first bias up such
sensors with a constant current source (LM317
wired like the Lo Ohms adapters described
on my website).
Select a bias current that is as large as
practical (means output delta-V in relation
to delta-R is greatest). Using constant
current excitation eliminate variability
of readings due to variations in bus voltage.
Then get yourself some rough calibration
curves for each style of sensor. Water bath
on stove works for temp sensors, air tank plumbed
to pressure sensor with some needle valves in the
pressure/bleed controls is handy.
Once you have ball-parked the voltages of
interest, you're ready to tackle the detection/
lamp drivers. The device you linked seems like
it should do the job. You may have a wiring
error . . . or perhaps are wrestling with outside
influences for not having stable excitation
sources for the sensors.
Another approach to consider is using a
micro-controller like the PIC12F683 . . . a
$1.00 device that will resolve a voltage,
deduce significance of its magnitude and
then do the appropriate hat dance to drive
the LED.
The cool thing is that you can put calibration
variables into separate, easily modified
memory locations such that no potentiometers
are needed. Takes a little more head-work to
calibrate the critter but once it's set,
you're all done and it won't drift. The task
you've described can probably be done with
no more than a single chip.
There are talented, experienced folks here
on the List that can help with your software
education. I probably have some etched circuit
boards laying around that are 95% of what
you need . . . already in existence along
with enclosures like . . .
http://www.aeroelectric.com/Catalog/AEC/9024/9024_Four_Fuction_
Perhaps this is more new te4rritory than you wanted
to explore but getting a couple of these things
up and running to your task would greatly expand
your horizons.
Bob . . .
________________________________________________________________________________
From: | rayj <raymondj(at)frontiernet.net> |
Subject: | Re: Half failed LEDs |
Most of them were in the 4-8k range both ways. A couple were in the 90k
range both ways, and one was about 90k one way and about 150k the other.
They were in series with other LEDs and all carried enough current to
allow the other LEDs to continue to light.
Raymond Julian
Kettle River, MN
The things we admire in men, kindness and generosity, openness, honesty,
understanding and feeling are the concomitants of failure in our system.
And those traits we detest, sharpness, greed, acquisitiveness, meanness,
egotism and self-interest are the traits of success. And while men
admire the quality of the first they love the produce of the second.
-John Steinbeck, novelist, Nobel laureate (1902-1968)
On 04/22/2014 08:18 AM, Robert L. Nuckolls, III wrote:
>
>
> At 07:09 AM 4/21/2014, you wrote:
>>
>> I just removed about 8 blue LEDs from a string of lights that no
>> longer emitted light, but still have continuity. If any one wants
>> them to investigate, I'll mail them out.
>
> When you measure them with an ohmmeter, do they
> show the same or similar resistance for either
> polarity of the test leads?
>
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Half failed LEDs |
At 10:31 AM 4/22/2014, you wrote:
>
>Most of them were in the 4-8k range both ways. A couple were in the
>90k range both ways, and one was about 90k one way and about 150k the other.
>
>
>They were in series with other LEDs and all carried enough current
>to allow the other LEDs to continue to light.
Interesting. I'm not familiar with the failure modes
in LEDs . . . so getting first hand look at the
parts would probably not be useful. The fact that
your readings were so high but with conductivity in
both directions suggests that there's some degree
of P/N junction activity going on . . . in other
words, I suspect they failed in some low energy
event as opposed to high energy that tends to fuse
things into more solid pieces of material.
Bob . . .
________________________________________________________________________________
From: | rayj <raymondj(at)frontiernet.net> |
Subject: | Re: Half failed LEDs |
They just weren't lit one day when I looked at them. They were on 24/7.
I'll just recycle them, unless someone else wants them.
Raymond Julian
Kettle River, MN
The things we admire in men, kindness and generosity, openness, honesty,
understanding and feeling are the concomitants of failure in our system.
And those traits we detest, sharpness, greed, acquisitiveness, meanness,
egotism and self-interest are the traits of success. And while men
admire the quality of the first they love the produce of the second.
-John Steinbeck, novelist, Nobel laureate (1902-1968)
On 04/22/2014 04:59 PM, Robert L. Nuckolls, III wrote:
>
>
> At 10:31 AM 4/22/2014, you wrote:
>>
>> Most of them were in the 4-8k range both ways. A couple were in the
>> 90k range both ways, and one was about 90k one way and about 150k the
>> other.
>>
>>
>> They were in series with other LEDs and all carried enough current to
>> allow the other LEDs to continue to light.
>
> Interesting. I'm not familiar with the failure modes
> in LEDs . . . so getting first hand look at the
> parts would probably not be useful. The fact that
> your readings were so high but with conductivity in
> both directions suggests that there's some degree
> of P/N junction activity going on . . . in other
> words, I suspect they failed in some low energy
> event as opposed to high energy that tends to fuse
> things into more solid pieces of material.
>
>
> Bob . . .
>
>
________________________________________________________________________________
Subject: | Re: warning lights for engine T&Ps |
From: | "user9253" <fransew(at)gmail.com> |
While looking for the collection of Op Amp circuits that Eric referred to, I found
this that might be useful to someone:
http://www.ti.com/lit/an/snla140b/snla140b.pdf
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422295#422295
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: warning lights for engine T&Ps |
At 10:11 AM 4/23/2014, you wrote:
>
>While looking for the collection of Op Amp circuits that Eric
>referred to, I found this that might be useful to someone:
>http://www.ti.com/lit/an/snla140b/snla140b.pdf
>Joe
>
>--------
>Joe Gores
Good find. This document is a classic. AN-31 has been
around for decades and updated many times. It's a great
teaching/learning tool!
Bob . . .
________________________________________________________________________________
From: | "rv7a.builder" <rv7a.builder(at)yahoo.com> |
Subject: | Voltage drop thru the essential bus diode as shown |
in Z-9.
I am getting about 3/4 of a volt drop through the essential buss diode when
the battery is at a full 12 volts.-When I throw the essential bus feed s
witch the Voltmeter creeps back up to 12 volts. Is this fairly normal?-Th
anks. John
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Voltage drop thru the essential bus diode as |
shown in Z-9.
At 04:08 PM 4/23/2014, you wrote:
>I am getting about 3/4 of a volt drop through the essential buss
>diode when the battery is at a full 12 volts. When I throw the
>essential bus feed switch the Voltmeter creeps back up to 12 volts.
>Is this fairly normal? Thanks. John
Yes. Diodes do have a small drop associated with
them . . . which is insignificant when the alternator
is running (bus at 14+ volts) and even less significant
when the alternator is not running because the alt-feed
switch is closed and the main bus is shut down.
Bob . . .
________________________________________________________________________________
Subject: | Re: warning lights for engine T&Ps |
From: | Sacha <uuccio(at)gmail.com> |
>
> The device you linked seems like
> it should do the job. You may have a wiring error...
I tested the circuit on the bench by simulating the senders with a bunch of 1k
ohm potentiometers wired in parallel (the resistance range of interest is 30-230
ohms approx in the case of the Rotax senders).
Turns out I had indeed made a wiring error.
The circuit I linked does the job perfectly as it's designed to measure resistance
so it's output is pretty much independent of bus voltage, so there was no
need for the dc-dc voltage regulator upstream.
I calibrated them by simulating the senders with the 1k pots and connecting them
to the gauges and the tri-color LED circuit. The sensitivity can be very finely
adjusted with the two 33-turn pots that are on the (approx 1x2 inch) circuit
board.
I also managed to adapt the circuit to measure absolute bus voltage (for the high/low
voltage light) by wiring a 7805 5v regulator thingy with three legs to
get a fixed reference voltage.
All in all I'm very satisfied with the results!
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: warning lights for engine T&Ps |
At 04:45 PM 4/24/2014, you wrote:
>
> >
> > The device you linked seems like
> > it should do the job. You may have a wiring error...
>
>I tested the circuit on the bench by simulating the senders with a
>bunch of 1k ohm potentiometers wired in parallel (the resistance
>range of interest is 30-230 ohms approx in the case of the Rotax senders).
>Turns out I had indeed made a wiring error.
>
>The circuit I linked does the job perfectly as it's designed to
>measure resistance so it's output is pretty much independent of bus
>voltage, so there was no need for the dc-dc voltage regulator upstream.
>
>I calibrated them by simulating the senders with the 1k pots and
>connecting them to the gauges and the tri-color LED circuit. The
>sensitivity can be very finely adjusted with the two 33-turn pots
>that are on the (approx 1x2 inch) circuit board.
>
>I also managed to adapt the circuit to measure absolute bus voltage
>(for the high/low voltage light) by wiring a 7805 5v regulator
>thingy with three legs to get a fixed reference voltage.
>
>All in all I'm very satisfied with the results!
Good for you sir . . .
Bob . . .
________________________________________________________________________________
From: | "DEAN PSIROPOULOS" <dean.psiropoulos(at)verizon.net> |
Subject: | SL-30 Poor VOR reception |
Hello listers:
I have an RV-6A that I've been flying for a few years. When I first started
flying the airplane I did some rough VOR range reception checks with the
SL-30 and I had to get within 20 miles of a VOR station to get the receiver
to lock on and the OBS indicator to stabilize with no flag displayed. I
continued with the flight test regimen and getting familiar with the
airplane and enjoying it. Since flights have been in VFR conditions around
the busy Tampa (Florida) airspace I used the panel mounted moving map
(GPS/Comm) to make sure I stayed out of the Class B, there was no need to
have good VOR reception. The Com portion was the only thing I was using on
the SL-30 and that worked very well. Then, a couple months ago I turned on
the SL-30 and, nothing, no display or Com so I returned the unit to Garmin
for repair. In the meantime I'd been talking to a CFII about working on
my instrument proficiency to get back up to FAA standards after a long
hiatus. When the SL-30 was repaired and back in the instrument panel I took
off on a flight to Ocala to check it out. I climbed up to 4500 feet and
watched the OBS and listened for the ID code as I entered the 40 mile radius
of the Ocala VOR. Nothing so I kept going on a course straight for the
station. Around 20-25 miles out I started getting activity on the indicator
but the flags were intermittent and the radio could not maintain a lock.
Finally about 15 miles out the indicators stabilized and the flags stayed
off, obviously something is amiss.
I'm using a Comant CI-159 VOR/ILS antenna. This unit consists of a phenolic
"puck" with a BNC connector cast into it for the coax connection. There are
two fiberglas elements (thin rods about 18 inches long) that screw into the
puck to form a "V" shaped antenna. I have it mounted on the bottom of the
fuselage in the back of the airplane under the horizontal stabilizer. The
BNC sticks through a hole in the belly and appx 25 foot length of RG-58 coax
runs inside the aircraft up to the SL-30 receiver. No gasket was supplied
with the antenna so I just bolted the puck to the aluminum using the two
bolt holes. After the Ocala flight I removed the puck and elements for
closer inspection and checked the connector on the coax cable at the antenna
end. Nothing wrong that I could tell just by looking at the equipment.
There was a bit of engine oil (from the exhaust) on the puck surface facing
the skin. I cleaned it off and made a gasket to go between the puck and the
skin to minimize the oil build up again. I have not flown the airplane
since but I doubt that lack of a gasket was causing the poor reception,
maybe someone here can tell me. The other thing I checked was the
resistance between the center pin and outside barrel of the BNC connector on
the antenna. Resistance was showing basically a dead short (less than 1
ohm, same reading as touching the meter probes together). I'm not an
antenna designer so I don't know if this is what the reading should be or
not. Aircraft Spruce has the following description for this antenna: " "V"
Dipole VOR/Glide Slope Antenna with detachable elements is similar to the CI
158C-3 with the exception of offering 2-hole mount instead of a 4-hole
mount. This V Dipole encompasses reduced static capability with the use of
P-Stat paint. Integral ferrite balun provides for higher radiation
efficiency." . I don't know if the construction of the antenna would cause
the meter to show such a low resistance, maybe some here could shed some
light on that.
Any ideas, experiences with poor VOR reception here on the list? Since the
radio has been repaired and tested by the factory I'd say it's not the
radio. I checked the connector at the back of the radio tray and it appears
secure so I'm not sure what else to do. Since VORs are being decommissioned
there is going to be less and less need for VOR reception but if I have to
use victor airways during instrument operations I need to have good
reception at the expected range or I won't be able to comply with ATC
clearances. On an side note, a fellow RV-9 builder who is using a simple
flat metal antenna in the wingtip, has no problem receiving the VOR 40 miles
out, and he didn't pay anywhere near what I did for his antenna. Thanks for
the help
Dean Psiropoulos
RV-6A N197DM
200+ hours since 2008
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: SL-30 Poor VOR reception |
When the SL-30 was repaired and back in the instrument panel I took
off on a flight to Ocala to check it out. I climbed up to 4500 feet and
watched the OBS and listened for the ID code as I entered the 40 mile radius
of the Ocala VOR. Nothing so I kept going on a course straight for the
station. Around 20-25 miles out I started getting activity on the indicator
but the flags were intermittent and the radio could not maintain a lock.
Finally about 15 miles out the indicators stabilized and the flags stayed
off, obviously something is amiss.
Since the radio has enjoyed a recent bench check,
probability of it being a radio problem is considerably
reduced . . . at the bottom of the list . . .
I have not flown the airplane since but I doubt that lack of a gasket
was causing the poor reception, maybe someone here can tell me.
Agreed . . . gaskets tend to be hedges against
moisture/dirt and have no effect on performance
of any antenna.
The other thing I checked was the
resistance between the center pin and outside barrel of the BNC connector on
the antenna. Resistance was showing basically a dead short (less than 1
ohm, same reading as touching the meter probes together).
40 years ago, this would be uncommon. Nowadays, antenna
designers have deduced value for incorporation of impedance
matching a balancing networks between the antenna element(s)
and the feed line. Further, designing a network with a
DC path to ground is a further improvement for reduction of
noise due to p-static.
This V Dipole encompasses reduced static capability with the use of
P-Stat paint.
A further step forward in the art and science of antennas
for aircraft.
Integral ferrite balun provides for higher radiation efficiency."
Yeah . . . sort of . . . measurable in the lab but
of zero observable significance to the pilot.
I don't know if the construction of the antenna would cause
the meter to show such a low resistance, maybe some here could shed some
light on that.
Yes . . . your observations are not out of the
ordinary . . .
Any ideas, experiences with poor VOR reception here on the list? Since the
radio has been repaired and tested by the factory I'd say it's not the
radio. I checked the connector at the back of the radio tray and it appears
secure so I'm not sure what else to do. Since VORs are being decommissioned
there is going to be less and less need for VOR reception but if I have to
use victor airways during instrument operations I need to have good
reception at the expected range or I won't be able to comply with ATC
clearances. On an side note, a fellow RV-9 builder who is using a simple
flat metal antenna in the wingtip, has no problem receiving the VOR 40 miles
out, and he didn't pay anywhere near what I did for his antenna. Thanks for
the help.
A not uncommon observation. The quest for uber-efficient
antennas on aircraft is problematic. The guys with hammers-
n-saws in the lab can do a fine job of 'optimizing' a
design to textbook ideals but we're not communicating
with space probes or folks with hand-helds over the
horizon.
The nominal signal-to-noise ratios for air-to-ground
contact by radio are huge. For the most part, a "wet-string"
will offer serviceable performance as an antenna.
Do you have access to an antenna analyzer . . .
Emacs!
or perhaps an SWR meter . . .
Emacs!
The FIRST thing to do after checking the obvious (mechanical
connections) is to get some numbers. An antenna analyzer hooked
to the receiver end of the transmission line is the best
way to assess antenna health. Even use of an SWR meter
like the 'red dot' instruments off eBay can be excited with
the ship's comm transceiver (or a hand held) set to
the lowest comm frequency. The SWR should be relatively
low even though you're measuring at the top of it's
design range.
Put a dummy load
http://tinyurl.com/cchp3pf
at the antenna end of your VOR feed line, connect
the feedline to the transceiver and then "talk"
to it while monitoring SWR.
Alternatively, make a temporary connection of your
comm antenna into the VOR receiver input jack and
go fly the airplane. I'm betting that you're going
to see a marked improvement in VOR performance.
If your access to test equipment is limited,
you can play the swaptronics game . . . replace
the connectors on the ends of the feed line just
for the heck of it. It takes less time to do this
simple experiment than all the time spent thus
far looking for 'rate in the woodpile'.
It seems unlikely that the antenna is at fault.
feedline installation errors are a higher
probability.
What ever the problem is . . . it's stone simple
Bob . . .
________________________________________________________________________________
Subject: | Re: SL-30 Poor VOR reception |
From: | "user9253" <fransew(at)gmail.com> |
There could be a problem with one of the coax connectors. You could replace the
RG-58 cable with RG-400, which has less signal loss. If the coax is bent with
too small of a radius, that can cause problems. Another concern is the antenna
location. What is the distance between the horizontal stabilizer and the
antenna? This distance can have a big affect on the antenna performance.
Radio Frequency current behaves much differently than DC current. An open circuit
for DC can be a short circuit for RF. And a short circuit for DC can be an
open circuit for RF.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422373#422373
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Bob,
I forgot to say thank you for the magneto trouble-shooting guide you sent a couple
of weeks ago...
So thank you, very helpful
-Jeff
________________________________________________________________________________
From: | "David Lloyd" <skywagon(at)charter.net> |
Subject: | Re: SL-30 Poor VOR reception |
Great advice by all concerning this problem . . . .
However, I would not place the fact that the radio just came out of
factory bench testing on the bottom of the problem list.
I have had a few situations where factory repairs were very much less
than acceptable.
The latest was an autopilot recalibration when GPS tracking was not
accurate. Unit came back still with poor tracking. After much arguing
with company, an officer went down to the final bench test and
calibration station and found an error in the factory final test set-up.
Another was a Navigator that had very specific squelch breaks occurring
at odd but, specific frequencies. Turned out the auto squelch factory
test stand was set-up wrong.
I don't understand how such problems can exist in a well respected
company but, it happens.
Let us know what you find with your radio problem. . .
-------------------------------------------------------------------------
-------
----- Original Message -----
From: Robert L. Nuckolls, III
To: aeroelectric-list(at)matronics.com
Sent: Friday, April 25, 2014 8:52 AM
Subject: Re: AeroElectric-List: SL-30 Poor VOR reception
When the SL-30 was repaired and back in the instrument panel I took
off on a flight to Ocala to check it out. I climbed up to 4500 feet
and
watched the OBS and listened for the ID code as I entered the 40 mile
radius
of the Ocala VOR. Nothing so I kept going on a course straight for the
station. Around 20-25 miles out I started getting activity on the
indicator
but the flags were intermittent and the radio could not maintain a
lock.
Finally about 15 miles out the indicators stabilized and the flags
stayed
off, obviously something is amiss.
Since the radio has enjoyed a recent bench check,
probability of it being a radio problem is considerably
reduced . . . at the bottom of the list . . .
I have not flown the airplane since but I doubt that lack of a gasket
was causing the poor reception, maybe someone here can tell me.
Agreed . . . gaskets tend to be hedges against
moisture/dirt and have no effect on performance
of any antenna.
The other thing I checked was the
resistance between the center pin and outside barrel of the BNC
connector on
the antenna. Resistance was showing basically a dead short (less than
1
ohm, same reading as touching the meter probes together).
40 years ago, this would be uncommon. Nowadays, antenna
designers have deduced value for incorporation of impedance
matching a balancing networks between the antenna element(s)
and the feed line. Further, designing a network with a
DC path to ground is a further improvement for reduction of
noise due to p-static.
This V Dipole encompasses reduced static capability with the use of
P-Stat paint.
A further step forward in the art and science of antennas
for aircraft.
Integral ferrite balun provides for higher radiation efficiency."
Yeah . . . sort of . . . measurable in the lab but
of zero observable significance to the pilot.
I don't know if the construction of the antenna would cause
the meter to show such a low resistance, maybe some here could shed
some
light on that.
Yes . . . your observations are not out of the
ordinary . . .
Any ideas, experiences with poor VOR reception here on the list? Since
the
radio has been repaired and tested by the factory I'd say it's not the
radio. I checked the connector at the back of the radio tray and it
appears
secure so I'm not sure what else to do. Since VORs are being
decommissioned
there is going to be less and less need for VOR reception but if I
have to
use victor airways during instrument operations I need to have good
reception at the expected range or I won't be able to comply with ATC
clearances. On an side note, a fellow RV-9 builder who is using a
simple
flat metal antenna in the wingtip, has no problem receiving the VOR 40
miles
out, and he didn't pay anywhere near what I did for his antenna.
Thanks for
the help.
A not uncommon observation. The quest for uber-efficient
antennas on aircraft is problematic. The guys with hammers-
n-saws in the lab can do a fine job of 'optimizing' a
design to textbook ideals but we're not communicating
with space probes or folks with hand-helds over the
horizon.
The nominal signal-to-noise ratios for air-to-ground
contact by radio are huge. For the most part, a "wet-string"
will offer serviceable performance as an antenna.
Do you have access to an antenna analyzer . . .
or perhaps an SWR meter . . .
The FIRST thing to do after checking the obvious (mechanical
connections) is to get some numbers. An antenna analyzer
hooked
to the receiver end of the transmission line is the best
way to assess antenna health. Even use of an SWR meter
like the 'red dot' instruments off eBay can be excited with
the ship's comm transceiver (or a hand held) set to
the lowest comm frequency. The SWR should be relatively
low even though you're measuring at the top of it's
design range.
Put a dummy load
http://tinyurl.com/cchp3pf
at the antenna end of your VOR feed line, connect
the feedline to the transceiver and then "talk"
to it while monitoring SWR.
Alternatively, make a temporary connection of your
comm antenna into the VOR receiver input jack and
go fly the airplane. I'm betting that you're going
to see a marked improvement in VOR performance.
If your access to test equipment is limited,
you can play the swaptronics game . . . replace
the connectors on the ends of the feed line just
for the heck of it. It takes less time to do this
simple experiment than all the time spent thus
far looking for 'rate in the woodpile'.
It seems unlikely that the antenna is at fault.
feedline installation errors are a higher
probability.
What ever the problem is . . . it's stone simple
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: SL-30 Poor VOR reception |
At 01:12 PM 4/25/2014, you wrote:
>Great advice by all concerning this problem . . . .
>
>However, I would not place the fact that the radio just came out of
>factory bench testing on the bottom of the problem list.
>
>I have had a few situations where factory repairs were very much
>less than acceptable.
>The latest was an autopilot recalibration when GPS tracking was not
>accurate. Unit came back still with poor tracking. After much
>arguing with company, an officer went down to the final bench test
>and calibration station and found an error in the factory final test set-up.
>Another was a Navigator that had very specific squelch breaks
>occurring at odd but, specific frequencies. Turned out the auto
>squelch factory test stand was set-up wrong.
>I don't understand how such problems can exist in a well respected
>company but, it happens.
>
>Let us know what you find with your radio problem. . .
Another investigative test option is to attach
a VOR/COMM hand held to the antenna feed line
to rule out panel mounted radio problems.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
At 01:00 PM 4/25/2014, you wrote:
>Bob,
>
>I forgot to say thank you for the magneto trouble-shooting guide you
>sent a couple of weeks ago...
>
>So thank you, very helpful
>
>-Jeff
What did you find?
Bob . . .
________________________________________________________________________________
From: | "j. davis" <jwd3ca(at)gmail.com> |
I'd be interested in seeing that, Jeff. Thanks!
On 25 Apr 2014 14:09, "Jeff Luckey" wrote:
> Bob,
>
> I forgot to say thank you for the magneto trouble-shooting guide you sent
> a couple of weeks ago...
>
> So thank you, very helpful
>
> -Jeff
>
> *
>
>
> *
>
>
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Per request from J. Davis...=0A=0A=0A----- Forwarded Message -----=0AFrom:
"Robert L. Nuckolls, III" =0ATo: aeroelectri
c-list(at)matronics.com =0ASent: Tuesday, April 8, 2014 8:06 AM=0ASubject: Re:
AeroElectric-List: Magneto Noise=0A =0A=0A--> AeroElectric-List message po
sted by: "Robert L. Nuckolls, III" =0A=0AAt
12:04 PM 4/6/2014, you wrote:=0A=0AI flew w/ a friend recently and when try
ing to get awos for our =0Adestination airport (which is a pretty weak sign
al) it was almost =0Aimpossible to hear due to magneto noise.- The radio
is a Garmin 430W =0Ain a Cherokee and we were around 10 miles from the airp
ort.- When we =0Agot within 3 or 4 miles the signal was much clearer.-
All other =0Atransmissions with ATC & towers were acceptable but I noticed
at high =0Avolume I could clearly hear magneto noise in the background.=0A
=0AI'm wondering if that's just the way it is or if there is a problem =0Aw
ith the magnetos or P lead wiring.=0A=0A- - Was this a new condition or
has it been that=0A- - way 'forever'. It's difficult for the neophyte
=0A- - observer to tell the difference between ignition=0A- - noise
s getting into the system by way of plug wire=0A- - radiation versus p-
lead radiation.=0A=0A- - First, make sure that the perceived noise goes
up=0A- - and down with volume control settings on radio.=0A- - Thi
s all but guarantees that it's coming in through=0A- - the antenna.=0A
=0A- - Then, disconnect both p-leads from the back of the=0A- - mag
netos and run the engine. See if the noise is=0A- - still heard . . . t
urn to unused frequency . . .=0A- - open squelch.=0A=0A- - If you c
an still hear it, then look for bad plug=0A- - wire. If not, hook up on
e p-lead at a time and=0A- - repeat experiment . . . see if noise is pr
edicated=0A- - on either or both of the p-leads being hooked up.=0A=0A
- - Once you've identified the offending radiator,=0A- - you need t
o figure out why. If this is a 'new'=0A- - condition, then you're looki
ng for something that=0A- - has changed. Bad cap in mag (probably not b
oth)=0A- - broken ground lead on p-lead shield. If possible/=0A- -
practical wire p-lead wires per Figure Z-27=0A=0Ahttp://tinyurl.com/n3oy37f
=0A=0A- - Ground p-lead shields at magneto end only . . .=0A- - use
p-lead shields to ground mag switch. Remove=0A- - and existing ground
to the mag switch.=0A=0A- - If the noise is coming from both p-leads,
=0A- - there are 'approved' magneto noise filters=0A=0Ahttp://tinyurl.c
om/l3s4mrj=0A=0A- - that most mechanics will install with a simple=0A
- - log-book entry.=0A=0A- - Bob . . .=0A=0A=0A- Bob . . .-
====================
________________________________________________________________________________
Subject: | Re: Magneto Noise |
From: | "j. davis" <jwd3ca(at)gmail.com> |
Thanks, Jeff. I was thinking it had to do with ignition issues (rather than
radio noise ) but I'll file it away for future reference.
On 25 Apr 2014 16:08, "Jeff Luckey" wrote:
> Per request from J. Davis...
>
>
> ----- Forwarded Message -----
> *From:* "Robert L. Nuckolls, III"
> *To:* aeroelectric-list(at)matronics.com
> *Sent:* Tuesday, April 8, 2014 8:06 AM
> *Subject:* Re: AeroElectric-List: Magneto Noise
>
> nuckolls.bob(at)aeroelectric.com>
>
> At 12:04 PM 4/6/2014, you wrote:
>
> I flew w/ a friend recently and when trying to get awos for our
> destination airport (which is a pretty weak signal) it was almost
> impossible to hear due to magneto noise. The radio is a Garmin 430W
> in a Cherokee and we were around 10 miles from the airport. When we
> got within 3 or 4 miles the signal was much clearer. All other
> transmissions with ATC & towers were acceptable but I noticed at high
> volume I could clearly hear magneto noise in the background.
>
> I'm wondering if that's just the way it is or if there is a problem
> with the magnetos or P lead wiring.
>
> Was this a new condition or has it been that
> way 'forever'. It's difficult for the neophyte
> observer to tell the difference between ignition
> noises getting into the system by way of plug wire
> radiation versus p-lead radiation.
>
> First, make sure that the perceived noise goes up
> and down with volume control settings on radio.
> This all but guarantees that it's coming in through
> the antenna.
>
> Then, disconnect both p-leads from the back of the
> magnetos and run the engine. See if the noise is
> still heard . . . turn to unused frequency . . .
> open squelch.
>
> If you can still hear it, then look for bad plug
> wire. If not, hook up one p-lead at a time and
> repeat experiment . . . see if noise is predicated
> on either or both of the p-leads being hooked up.
>
> Once you've identified the offending radiator,
> you need to figure out why. If this is a 'new'
> condition, then you're looking for something that
> has changed. Bad cap in mag (probably not both)
> broken ground lead on p-lead shield. If possible/
> practical wire p-lead wires per Figure Z-27
>
> http://tinyurl.com/n3oy37f
>
> Ground p-lead shields at magneto end only . . .
> use p-lead shields to ground mag switch. Remove
> and existing ground to the mag switch.
>
> If the noise is coming from both p-leads,
> there are 'approved' magneto noise filters
>
> http://tinyurl.com/l3s4mrj
>
> that most mechanics will install with a simple
> log-book entry.
>
> Bob . . .
>
>
> Bob . . .
>
> >
>
>
> <http://www.matronics.com/Navigator?AeroElectric-List>
>
> *
>
>
> *
>
>
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
At the moment, my findings are inconclusive.- =0A=0AI began the test proc
ess in the run-up area and found that I was not able to reproduce the sympt
oms.=0A=0A1. Engine @ 1800 RPM=0A2. Tune 430 to an unused freq=0A3. Open sq
uelch=0A=0AI did not hear the popping or buzzing sound that I heard a coupl
e of weeks ago in flight (which prompted my original query to the List).=0A
=0A=0AThen Life happened & I have not been able to get back to it - maybe t
his weekend.=0A=0A-Jeff=0A=0A=0A________________________________=0A From: "
Robert L. Nuckolls, III" =0ATo: aeroelectric
-list(at)matronics.com =0ASent: Friday, April 25, 2014 12:03 PM=0ASubject: Re:
AeroElectric-List: Thanks Bob=0A =0A=0A--> AeroElectric-List message poste
d by: "Robert L. Nuckolls, III" =0A=0AAt 01:
00 PM 4/25/2014, you wrote:=0A>Bob,=0A>=0A>I forgot to say thank you for th
e magneto trouble-shooting guide you =0A>sent a couple of weeks ago...=0A>
=0A>So thank you, very helpful=0A>=0A>-Jeff=0A=0A- What did you find?=0A
- - - - - - - - - - - - -Matt Dralle, List Admin.
====
________________________________________________________________________________
From: | Kelly McMullen <kellym(at)aviating.com> |
Subject: | Re: SL-30 Poor VOR reception |
I agree with connector issues. I do NOT agree with cable issues. Ever
since the VOR came on the scene, RG-58 has proved more than adequate on
factory built spam cans. Most have runs of over 20 ft from panel to top
of tail. Often with one or more connectors in the line. I had such on a
Cessna that would easily receive 100nm on H class VOR at 10,000 ft. I
could connect handheld to splitter for same antenna and it also would
receive same 100+ nm range. RG 142 and 400 are better, but not 6 times
better, which is the price difference. I doubt they are even 50% better.
On 4/25/2014 10:32 AM, user9253 wrote:
>
> There could be a problem with one of the coax connectors. You could replace
the RG-58 cable with RG-400, which has less signal loss. If the coax is bent
with too small of a radius, that can cause problems. Another concern is the antenna
location. What is the distance between the horizontal stabilizer and the
antenna? This distance can have a big affect on the antenna performance.
> Radio Frequency current behaves much differently than DC current. An open circuit
for DC can be a short circuit for RF. And a short circuit for DC can be
an open circuit for RF.
> Joe
>
> --------
> Joe Gores
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=422373#422373
>
>
________________________________________________________________________________
From: | D L Josephson <dlj04(at)josephson.com> |
Subject: | Re: Avionics-List: Garmin SL-30 poor VOR reception |
This question is being discussed both here and on the avionics list.
Commercial RG-58A, mil spec RG-58 (MIL-DTL-17 M17/28-RG058) such as
Belden 9203, RG-142 and RG400/LMR400 are all rated between 3.3 and 4.9
dB per 100 ft at 100 MHz -- around 1 dB for a practical airplane
installation. Belden 9203 RG58 is among the lowest loss and is mil QPL
qualified. Cable loss is not really a factor in a VOR/LOC/GS
installation; well made RG58 cable is fine. Cheap RG-58 "type" cable of
unknown impedance and bend resistance, who knows.
Original RG-58 (solid center conductor, solid PE dielectric) was just
fine for decades with receivers far worse than the Garmin. In my
experience, connectors are the problem nine times out of ten. Commercial
grade crimp connectors from a manufacturer that also supplies military
grade connectors (Amp, Amphenol, Kings) crimped with the
manufacturer-specified or mil-spec tool checked for the correct crimp
dimensions by someone experienced with this process is the key. Original
military soldered connectors are also OK but only if the installer is
experienced enough to get the dimensions right without melting the
dielectric.
Quick test, after you've confirmed that the cable has continuity end to
end and isn't shorted: grab the cable in one hand and the body of the
connector or the crimp sleeve in the other. Using moderate force, can
you rotate the connector body with respect to the cable? If so, cut it
off and try again, it is not terminated correctly. This isn't the cause
of all problems but is usually diagnostic of whether it was crimped
right in the first place.
The tests Bob suggested are good. A nav receiver will work well -- not
optimally for IFR but well enough -- on a comm antenna.
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: SL-30 Poor VOR reception |
At 04:47 PM 4/25/2014, you wrote:
>
>I agree with connector issues. I do NOT agree with cable issues.
>Ever since the VOR came on the scene, RG-58 has proved more than
>adequate on factory built spam cans. Most have runs of over 20 ft
>from panel to top of tail. Often with one or more connectors in the
>line. I had such on a Cessna that would easily receive 100nm on H
>class VOR at 10,000 ft. I could connect handheld to splitter for
>same antenna and it also would receive same 100+ nm range. RG 142
>and 400 are better, but not 6 times better, which is the price
>difference. I doubt they are even 50% better.
Agreed. The strength of vor transmitters and the
fundamentally line-of-sight operation makes
signal loss in coax a non-issue. The greatest
gain for a modern coax is in quality of insulation.
Legacy RG-58 is pvc and polyethylene while
the modern plastics are tefzel and more robust
cousins.
RG-400 and siblings are preferred for new
construction but I wouldn't replace RG-58
already in place.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Speaking of coax |
While we're on the subject, know that there's a new
line of coax cables being offered as lower loss and
better shielded than the legacy RG products of PVC/PE . . .
They are part of the LMR series products like this
http://tinyurl.com/l2xbbqr
The value of the part numbers is the outside
diameter in thousandths. Hence, LMR195 is the
same physical size as RG58 and RG400.
The insulation is not high temperature rated,
it's more on the order of that stated for RG58
so soldering connectors to this stuff takes some
practice.
However, for all crimped joints, there's little
difference between the LMR and any other style.
The LMR195 has a solid center conductor which
harkens back to the days when solid center
conductor RG58 can short to the shield if
installed with a sharp bend radius and then
subjected to many years of temperature cycling.
This is a low-risk failure . . . I've only heard
of it one time and that was while I was still
at Cessna the first time.
The center conductor insulation is foamed
which produces a lower loss than legacy RG-58.
The shield is a combination of braid over
foil which offers near perfect shielding.
. . . and the price is right.
Bob . . .
________________________________________________________________________________
Subject: | Single ground vs. distributed ground |
I'm in the process of wiring the panel and avionics on my Velocity (composite,
canard).
I have built an Avionics Shelf which runs the width of the cabin just behind the
panel. The shelf is made out of a pair of 1" aluminum angle stock and a sheet
of aluminum on top.
On the right side of the shelf I have mounted a ground block that connects to the
battery via 2AWG welding cable.
As I am connecting wires, the number of wires that are attaching to the ground
block keeps increasing. [Embarassed]
I can think of a couple of solutions:
1) crimp multiple wires to a single terminal. With the 22AWG wires, I could get
up to four wires in a single (red) terminal .
2) Make another ground block and mount it to the left side on the avionics shelf.
This would have the added benefit of eliminating ground wires from the bundle
crossing over to the right side ground block.
I'm leaning towards #2, but I'm wondering what the opinions are on these solutions
or if there's one I haven't thought of.
Thanks in advance.
Don
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422415#422415
________________________________________________________________________________
Subject: | Re: Single ground vs. distributed ground |
From: | Tim Andres <tim2542(at)sbcglobal.net> |
Buy an avionics ground bus from Bob K. Sweet and simple single point ground system
for the avionics.
Just wondering....why 2awg wire to the avionics? Seems rather large.
Tim
> On Apr 26, 2014, at 2:12 PM, "donjohnston" <don@velocity-xl.com> wrote:
>
>
> I'm in the process of wiring the panel and avionics on my Velocity (composite,
canard).
>
> I have built an Avionics Shelf which runs the width of the cabin just behind
the panel. The shelf is made out of a pair of 1" aluminum angle stock and a sheet
of aluminum on top.
>
> On the right side of the shelf I have mounted a ground block that connects to
the battery via 2AWG welding cable.
>
> As I am connecting wires, the number of wires that are attaching to the ground
block keeps increasing. [Embarassed]
>
> I can think of a couple of solutions:
>
> 1) crimp multiple wires to a single terminal. With the 22AWG wires, I could get
up to four wires in a single (red) terminal .
>
> 2) Make another ground block and mount it to the left side on the avionics shelf.
This would have the added benefit of eliminating ground wires from the bundle
crossing over to the right side ground block.
>
> I'm leaning towards #2, but I'm wondering what the opinions are on these solutions
or if there's one I haven't thought of.
>
> Thanks in advance.
> Don
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=422415#422415
>
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
Subject: | Re: Single ground vs. distributed ground |
tim2542(at)sbcglobal.net wrote:
> Buy an avionics ground bus from Bob K.
Well that would result in scrapping and undoing what I've already done.
> Just wondering....why 2awg wire to the avionics? Seems rather large.
Couple of reason: 1) I have more than just the avionics being grounded at that
block (trim motor, AP servo, cooling fan, etc.). 2) I had the wire and the room.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422418#422418
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: OT: power supply noise |
At 03:10 PM 4/26/2014, you wrote:
>
>Greetings,
>
>I'm considering putting an unregulated power supply (transformers,
>diodes, and a condenser) in an old computer box along with the
>electronics to run several stepper motors for a CNC system.
>
>I'm wondering if noise radiated from the power supply will cause
>problems for the stepper motor drivers.
Probably not. Do you have these parts already in hand?
Regulated, clean power supplies up to 350W are pretty
cheap on eBay. I seldom build a supply any more, the labor
alone is more than the cost of an off-the-shelf, plug-n-play
device.
Bob . . .
________________________________________________________________________________
From: | "Carlos Trigo" <trigo(at)mail.telepac.pt> |
Subject: | Linking 2 coax cables |
Guys
I had to cut and throw away some 2 feet of a Comm antenna cable which I
found that had a burnt spot.
I don't want to replace all the coax cable, which would be a PIA to do.
I also know that I can use a male and a female BNC connectors to make a 2
feet extension, but
Is there an elegant and efficient way to connect 2 coax cables to each
other, without using a male and a female connectors?
Regards
Carlos
---
Este email est livre de vrus e malware porque a proteo avast! Antivirus est ativa.
http://www.avast.com
________________________________________________________________________________
From: | "rv7a.builder" <rv7a.builder(at)yahoo.com> |
Subject: | Amp meter jumps when transmitting |
Hello Group,=0A---- I have a Vans amp meter installed in my RV-7A.
When I activate the PTT on the Garmin GNC300XL-the amp meter jumps to ful
l scale. I disconnect the antenna coax from back of the radio and hit the P
TT and the amp meter needle stays still. I turn off the radio and bring my
handheld into the cockpit and hit the transmit button from 2 feet away-an
d a very slight movement in the amp meter is detected.-Bringing the handh
eld closer to the amp meter will make the needle jump more when the PTT is
activated.-I think I have-determined this to be a RF-inference proble
m.-My questions are 1) Will the amp meter eventually be damaged by these
extreme movements? 2) Is there a fix? 3) Am I alone here or have others exp
erience this phenomena?=0A-=0AThanks. John. RV-7A Just about ready to fly
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Amp meter jumps when transmitting |
At 07:35 AM 4/27/2014, you wrote:
Hello Group,
I have a Vans amp meter installed in my RV-7A. When I activate
the PTT on the Garmin GNC300XL the amp meter jumps to full scale. I
disconnect the antenna coax from back of the radio and hit the PTT
and the amp meter needle stays still. I turn off the radio and bring
my handheld into the cockpit and hit the transmit button from 2 feet
away and a very slight movement in the amp meter is detected.
Bringing the handheld closer to the amp meter will make the needle
jump more when the PTT is activated. I think I have determined this
to be a RF inference problem.
I bought a Van's ammeter some years ago to
explore it's vulnerabilities to strong RF.
See pictures here:
http://tinyurl.com/mpx8hze
I discovered that no only was the instrument
devoid of any firewall for RF interference,
it was even directionally sensitive!!! See
pictures
http://tinyurl.com/m4xlj2u
http://tinyurl.com/kvo4vwk
Just waving the hand-held from side to side
would produce behaviors in the pointer error
that mimicked the motion of the antenna.
My questions are 1) Will the amp meter eventually be damaged by these
extreme movements?
No
2) Is there a fix?
Probably, but labor intensive and clumsy on
a finished instrument. It would have been FAR
better that the manufacturer demonstrated
a knowledge of DO-160 in the first place.
3) Am I alone here or have others experience this phenomena?
No doubt there are many others. Since it's
a transient event that affects the display
only while talking, it's a cosmetic behavior.
You might consider just 'living' with it.
With one caveat . . . make sure that your coax
connectors are good at both ends of the feedline . . .
it wouldn't hurt to do an SWR check. The
phenomenon you're observing MIGHT be the
result of a very RF-Hot cockpit due to loss
of shield ground on either end of the coax.
But it your antenna system is golden, then
there are no risks for just ignoring it.
I wrote to Van's about this condition . . . never
heard back from them. It no doubt affects
their entire line of instruments with
electronic signal conditioning.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Linking 2 coax cables |
At 06:37 AM 4/27/2014, you wrote:
>
>
>Guys
>
>I had to cut and throw away some 2 feet of a Comm antenna cable which I
>found that had a burnt spot.
>I don't want to replace all the coax cable, which would be a PIA to do.
>I also know that I can use a male and a female BNC connectors to make a 2
>feet extension, but
>Is there an elegant and efficient way to connect 2 coax cables to each
>other, without using a male and a female connectors?
Yeah, sort of but it's pretty process sensitive.
I'd vote for the connectors.
Bob . . .
________________________________________________________________________________
From: | "rv7a.builder" <rv7a.builder(at)yahoo.com> |
Subject: | Re: Amp meter jumps when transmitting |
Thanks Bob for that great analysis. John.=0AOn Sunday, April 27, 2014 6:57
AM, "Robert L. Nuckolls, III" wrote:=0A
olls.bob(at)aeroelectric.com>=0A=0AAt 07:35 AM 4/27/2014, you wrote:=0AHello G
roup,=0A- - - I have a Vans amp meter installed in my RV-7A. When I a
ctivate =0Athe PTT on the Garmin GNC300XL the amp meter jumps to full scale
. I =0Adisconnect the antenna coax from back of the radio and hit the PTT
=0Aand the amp meter needle stays still. I turn off the radio and bring =0A
my handheld into the cockpit and hit the transmit button from 2 feet =0Aawa
y and a very slight movement in the amp meter is detected. =0ABringing the
handheld closer to the amp meter will make the needle =0Ajump more when the
PTT is activated. I think I have determined this =0Ato be a RF inference p
roblem.=0A=0A- - I bought a Van's ammeter some years ago to=0A- - e
xplore it's vulnerabilities to strong RF.=0A=0A- - See pictures here:
=0A=0Ahttp://tinyurl.com/mpx8hze=0A=0A- - I discovered that no only was
the instrument=0A- - devoid of any firewall for RF interference,=0A-
- it was even directionally sensitive!!! See=0A- - pictures=0A=0Ahtt
p://tinyurl.com/m4xlj2u=0A=0Ahttp://tinyurl.com/kvo4vwk=0A=0A- - Just w
aving the hand-held from side to side=0A- - would produce behaviors in
the pointer error=0A- - that mimicked the motion of the antenna.=0A=0A
=0AMy questions are 1) Will the amp meter eventually be damaged by these
=0Aextreme movements?=0A=0A- - No=0A=0A- 2) Is there a fix?=0A=0A-
- Probably, but labor intensive and clumsy on=0A- - a finished instru
ment. It would have been FAR=0A- - better that the manufacturer demonst
rated=0A- - a knowledge of DO-160 in the first place.=0A=0A- 3) Am I
alone here or have others experience this phenomena?=0A=0A=0A- - No dou
bt there are many others. Since it's=0A- - a transient event that affec
ts the display=0A- - only while talking, it's a cosmetic behavior.=0A
- - You might consider just 'living' with it.=0A=0A- - With one cav
eat . . . make sure that your coax=0A- - connectors are good at both en
ds of the feedline . . .=0A- - it wouldn't hurt to do an SWR check.-
The=0A- - phenomenon you're observing MIGHT be the=0A- - result of
a very RF-Hot cockpit due to loss=0A- - of shield ground on either end
of the coax.=0A=0A- - But it your antenna system is golden, then=0A-
- there are no risks for just ignoring it.=0A=0A- - I wrote to Van's
about this condition . . . never=0A- - heard back from them. It no doub
t affects=0A- - their entire line of instruments with=0A- - electro
===============
________________________________________________________________________________
Subject: | Re: Amp meter jumps when transmitting |
From: | Dj Merrill <deej(at)deej.net> |
On 4/27/2014 8:35 AM, rv7a.builder wrote:
> I disconnect the antenna coax from back of the radio and hit the PTT
> and the amp meter needle stays still.
Just as an aside, it is generally a bad idea to activate a transmitter
with no antenna attached. There is a good chance of damaging the
transmitter by doing this.
fyi
-Dj
--
Dj Merrill - N1JOV - VP EAA Chapter 87
Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/
Glastar Flyer N866RH - http://deej.net/glastar/
________________________________________________________________________________
From: | rayj <raymondj(at)frontiernet.net> |
Subject: | Re: OT: power supply noise |
The parts were part of the CNC kit I bought years ago. It is the power
supply for the stepper motors. The output is in the neighborhood of 5
amps at 38Vdc The kit specified an UNregulated power supply because of
problems associated with back emf from the stepper motors as they
decelerate, as I understand it.
The motor drivers derive the required 5Vdc internally from the power
supply hookup.
My main concern was about radiated noise being picked up because they
are both inside an old metal computer case.
Thanks for the reply.
Raymond Julian
Kettle River, MN
The things we admire in men, kindness and generosity, openness, honesty,
understanding and feeling are the concomitants of failure in our system.
And those traits we detest, sharpness, greed, acquisitiveness, meanness,
egotism and self-interest are the traits of success. And while men
admire the quality of the first they love the produce of the second.
-John Steinbeck, novelist, Nobel laureate (1902-1968)
On 04/26/2014 10:56 PM, Robert L. Nuckolls, III wrote:
>
>
> At 03:10 PM 4/26/2014, you wrote:
>>
>> Greetings,
>>
>> I'm considering putting an unregulated power supply (transformers,
>> diodes, and a condenser) in an old computer box along with the
>> electronics to run several stepper motors for a CNC system.
>>
>> I'm wondering if noise radiated from the power supply will cause
>> problems for the stepper motor drivers.
>
> Probably not. Do you have these parts already in hand?
> Regulated, clean power supplies up to 350W are pretty
> cheap on eBay. I seldom build a supply any more, the labor
> alone is more than the cost of an off-the-shelf, plug-n-play
> device.
>
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "rv7a.builder" <rv7a.builder(at)yahoo.com> |
Subject: | Re: Amp meter jumps when transmitting |
Thanks for telling me that. I won't try that again. What actually happens t
hat could damage the transmitter? Thanks. John=0AOn Sunday, April 27, 2014
8:10 AM, Dj Merrill wrote:=0A =0A--> AeroElectric-List mes
sage posted by: Dj Merrill =0A=0AOn 4/27/2014 8:35 AM, rv7a.
builder wrote:=0A> I disconnect the antenna coax from back of the radio and
hit the PTT =0A> and the amp meter needle stays still.=0A=0AJust as an asi
de, it is generally a bad idea to activate a transmitter =0Awith no antenna
attached.- There is a good chance of damaging the =0Atransmitter by doin
g this.=0A=0Afyi=0A=0A-Dj=0A=0A-- =0ADj Merrill - N1JOV - VP EAA Chapter 87
=0ASportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/=0AGlasta
________________________________________________________________________________
Subject: | Re: Amp meter jumps when transmitting |
From: | Kevin Belue <kdb.rv10(at)gmail.com> |
I saw this problem years ago also. Their electronic manifold pressure gauge has
same issue. I replaced the MP with a non-electric version. The rest of my instruments
are from an EFIS. No problems with this configuration.
K. Belue
RV-10
Sent from my iPhone
On Apr 27, 2014, at 8:41 AM, "Robert L. Nuckolls, III"
wrote:
>
> At 07:35 AM 4/27/2014, you wrote:
> Hello Group,
> I have a Vans amp meter installed in my RV-7A. When I activate the PTT on
the Garmin GNC300XL the amp meter jumps to full scale. I disconnect the antenna
coax from back of the radio and hit the PTT and the amp meter needle stays
still. I turn off the radio and bring my handheld into the cockpit and hit the
transmit button from 2 feet away and a very slight movement in the amp meter
is detected. Bringing the handheld closer to the amp meter will make the needle
jump more when the PTT is activated. I think I have determined this to be a
RF inference problem.
>
> I bought a Van's ammeter some years ago to
> explore it's vulnerabilities to strong RF.
>
> See pictures here:
>
> http://tinyurl.com/mpx8hze
>
> I discovered that no only was the instrument
> devoid of any firewall for RF interference,
> it was even directionally sensitive!!! See
> pictures
>
> http://tinyurl.com/m4xlj2u
>
> http://tinyurl.com/kvo4vwk
>
> Just waving the hand-held from side to side
> would produce behaviors in the pointer error
> that mimicked the motion of the antenna.
>
>
> My questions are 1) Will the amp meter eventually be damaged by these extreme
movements?
>
> No
>
> 2) Is there a fix?
>
> Probably, but labor intensive and clumsy on
> a finished instrument. It would have been FAR
> better that the manufacturer demonstrated
> a knowledge of DO-160 in the first place.
>
> 3) Am I alone here or have others experience this phenomena?
>
>
> No doubt there are many others. Since it's
> a transient event that affects the display
> only while talking, it's a cosmetic behavior.
> You might consider just 'living' with it.
>
> With one caveat . . . make sure that your coax
> connectors are good at both ends of the feedline . . .
> it wouldn't hurt to do an SWR check. The
> phenomenon you're observing MIGHT be the
> result of a very RF-Hot cockpit due to loss
> of shield ground on either end of the coax.
>
> But it your antenna system is golden, then
> there are no risks for just ignoring it.
>
> I wrote to Van's about this condition . . . never
> heard back from them. It no doubt affects
> their entire line of instruments with
> electronic signal conditioning.
>
>
>
>
>
> Bob . . .
>
>
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Amp meter jumps when transmitting |
At 09:50 AM 4/27/2014, you wrote:
>
>On 4/27/2014 8:35 AM, rv7a.builder wrote:
>>I disconnect the antenna coax from back of the radio and hit the
>>PTT and the amp meter needle stays still.
>
>Just as an aside, it is generally a bad idea to activate a
>transmitter with no antenna attached. There is a good chance of
>damaging the transmitter by doing this.
Back in the days of germanium output transistors
(yes Martha, there WERE germanium devices capable
of several watts at VHF) it was considered poor
form if not instant death to one's output transistors
to key a transmitter into an open circuit.
Modern output devices are much more rugged. Further,
transmitters at-risk for high SWR damage are fitted
with automatic shut-down circuits for protection.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: OT: power supply noise |
At 09:56 AM 4/27/2014, you wrote:
>
>The parts were part of the CNC kit I bought years ago. It is the
>power supply for the stepper motors. The output is in the
>neighborhood of 5 amps at 38Vdc The kit specified an UNregulated
>power supply because of problems associated with back emf from the
>stepper motors as they decelerate, as I understand it.
Steppers don't generate back emf based on
motion of the moving parts. For the fastest
possible response time, steppers like to be
driven from high resistance if not purely constant
current power sources. It's all about that
t=L/R thingy.
The first stepper systems I crafted used banks
of power resistors to raise power source impedance.
Modern designs will use constant current output
stages in the drivers if they're seeking high
accuracy positioning along with fast response.
>The motor drivers derive the required 5Vdc internally from the power
>supply hookup.
>
>My main concern was about radiated noise being picked up because
>they are both inside an old metal computer case.
Your application would run quite well from unregulated,
full wave rectified AC as long as the 'relaxed' voltage
is not so high as to place output transistors at risk
in their OFF state.
Bob . . .
________________________________________________________________________________
Subject: | Re: Amp meter jumps when transmitting |
From: | Dj Merrill <deej(at)deej.net> |
On 4/27/2014 11:21 AM, rv7a.builder wrote:
> Thanks for telling me that. I won't try that again. What actually
> happens that could damage the transmitter? Thanks. John
Hi John,
I am sure someone else on here can explain the technical details
better than I, but the simple version is that if the transmitter does
not have circuitry built in to protect against it, it can blow some of
the parts in the final amplifier stage of the transmitter. Hopefully
someone else can chime in with more details of exactly how and why.
There is probably a good chance that a modern solid state radio has
this protection built in, but unless one knows for sure, there is no
reason to take the expensive chance that it doesn't. I'd be more
concerned with the older radios, but in general it is just good practice
to make sure that you have an antenna or a dummy load attached to the
antenna port before keying up the transmitter. My personal choice is to
make sure there is an antenna attached before even powering a radio on,
regardless of whether I am going to key the transmitter part.
-Dj
--
Dj Merrill - N1JOV - VP EAA Chapter 87
Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/
Glastar Flyer N866RH - http://deej.net/glastar/
________________________________________________________________________________
Subject: | Re: Linking 2 coax cables |
From: | "Eric M. Jones" <emjones(at)charter.net> |
Install a new cable or connectors. No other reasonable solution exists. Read my
article attached.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422475#422475
Attachments:
http://forums.matronics.com//files/dabbling_with_electricity_179.pdf
________________________________________________________________________________
From: | Henador Titzoff <henador_titzoff(at)yahoo.com> |
Subject: | Re: Amp meter jumps when transmitting |
Dj, John,=0A=0AHere's what happens when a transmitter hurls RF energy down
a transmission line.- First, the transmission line has a characteristic i
mpedance.- Impedance is almost like a resistance except it's comprised of
a mixture of capacitor reactance, inductive reactance and resistance.- R
eactances have currents and voltages that are 90 degrees out of phase.- T
his means they don't "burn" up any of the energy, whereas resistance has vo
ltage and current in phase and does burn up energy.- Check out the attach
ed picture from Wiki, which shows how the capacitance, inductance and resis
tances are modeled as lumped components. Ideally, the series and parallel r
esistances are zero.- In practice they're not but designers try to minimi
ze them to decrease attenuation.=0A=0A=0AWhen this energy traveling down th
e transmission line reaches the end, what happens?- If there's a resistor
there that is equal to the transmission line's characteristic impedance, t
hen ideally all of the energy is dissipated in that resistor as heat, since
the voltage and current waves are in phase.- If an antenna that is match
ed to the line is there, the power is magically transferred to the atmosphe
re, because the antenna's job is to match the impedance of the cable to fre
e space impedance, which is 376 Ohms.- It isn't really magic, at least ma
thematically, but one has to understand Maxwell's and Gaussian's laws to kn
ow how this happens and why free space impedance is 376 Ohms.=0A=0A=0ASo le
t's say the end of the transmission line is open or doesn't match the imped
ance.- In the open case, the energy has nowhere to go except to be transm
itted right back to where it came from.- Let's say the transmitter's tran
sistors are generating voltage waves that are 10V peak to peak.- This mea
ns that the designer has to choose components that can handle this voltage
plus some, say another 10V, in order to provide longevity and reliability.
- When the reflected energy arrives at the transmitter output, the two wa
ves (one going and one coming) can add up to a worst case number of 20V pea
k to peak if the phasing is correct. This comes very close to exceeding the
design limitation of the transmitter transistors.- If the designer specs
the transistors to less than 20V, then the two added waves' peak voltage c
ould very well destroy the transistors and/or other components.- The desi
gner could add transorbers or some other devices designed to limit the
voltage build up at the transmitter to keep it from malfunctioning, but it
's up to the designer and his design specs.=0A=0AAlso, the transmitter has
an impedance of its own, and for maximum power transfer it should equal the
line's impedance.- When the reflected wave comes back, if there is a sli
ght mismatch between the transmitter and line impedances, there will be som
e power dissipation at the transmitter but some of the power (wave) will re
flect back to the end of the line.- This means there are several waves on
the line, but each reflection decreases in amplitude because of losses alo
ng the line and at the ends.- All of these waves have to be added or subt
racted to find the real voltages at the ends.=0A=0ASo the bottom line is ca
n the transmitter handle the reflected waves such that when they add up, th
e end voltage doesn't damage the transmitter components, which of course ha
ve maximum voltage and power limits.- I add power in there because power
causes heat and components can only handle so much maximum temperature.=0A
=0AHope this helps.=0A-=0AHenador Titzoff=0A=0A=0A>______________________
__________=0A> From: Dj Merrill <deej(at)deej.net>=0A>To: aeroelectric-list@ma
tronics.com =0A>Sent: Sunday, April 27, 2014 6:52 PM=0A>Subject: Re: AeroEl
ectric-List: Amp meter jumps when transmitting=0A> =0A>=0A>--> AeroElectric
-List message posted by: Dj Merrill =0A>=0A>On 4/27/2014 11:
21 AM, rv7a.builder wrote:=0A>> Thanks for telling me that. I won't try tha
t again. What actually =0A>> happens that could damage the transmitter? Tha
nks. John=0A>=0A>Hi John,=0A>- - I am sure someone else on here can ex
plain the technical details =0A>better than I, but the simple version is th
at if the transmitter does =0A>not have circuitry built in to protect again
st it, it can blow some of =0A>the parts in the final amplifier stage of th
e transmitter. Hopefully =0A>someone else can chime in with more details of
exactly how and why.=0A>=0A>- - There is probably a good chance that
a modern solid state radio has =0A>this protection built in, but unless one
knows for sure, there is no =0A>reason to take the expensive chance that i
t doesn't.- I'd be more =0A>concerned with the older radios, but in gener
al it is just good practice =0A>to make sure=0A that you have an antenna or
a dummy load attached to the =0A>antenna port before keying up the transmi
tter.- My personal choice is to =0A>make sure there is an antenna attache
d before even powering a radio on, =0A>regardless of whether I am going to
key the transmitter part.=0A>=0A>-Dj=0A>=0A>-- =0A>Dj Merrill - N1JOV - VP
EAA Chapter 87=0A>Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/spor
========================0A>
=0A>=0A>=0A>=0A>=0A>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Amp meter jumps when transmitting |
>So the bottom line is can the transmitter handle the reflected waves
>such that when they add up, the end voltage doesn't damage the
>transmitter components, which of course have maximum voltage and
>power limits. I add power in there because power causes heat and
>components can only handle so much maximum temperature.
I'm aware of no supplier to aviation that does not
consider the rare but possible failure of a coax
connection . . . it's common practice to build
in protection, robustness or a combination of the
two.
Bob . . .
________________________________________________________________________________
From: | Henador Titzoff <henador_titzoff(at)yahoo.com> |
Subject: | Re: Amp meter jumps when transmitting |
This is very true, Bob, but I would also like to add that the possibility o
f an open in the connectors and coax is more common than "rare."- Most of
these failures occur during build, which are accidental, corrosion or fail
ure to tighten down connectors correctly.=0A=0A=0AWhile aviation suppliers
will consider the rare but possible failure you mention below, there are se
veral scenarios where this is not true.- One scenario is the supplier rec
eiving counterfeit parts that do not meet specs.- Another scenario is a s
hady buyer ordering the wrong parts and a faulty lot is manufactured and sh
ipped.- Manufactured lots vary from lot to lot, and some lots may sneak t
hrough that do not meet specifications but work well until "something happe
ns."- In particular, this business of counterfeit parts has been plaguing
manufacturing for at least two decades now.=0A=0A-=0AHenador Titzoff=0A
=0A=0A>________________________________=0A> From: "Robert L. Nuckolls, III"
=0A>To: aeroelectric-list(at)matronics.com =0A
>Sent: Sunday, April 27, 2014 8:44 PM=0A>Subject: Re: AeroElectric-List: Am
p meter jumps when transmitting=0A> =0A>=0A>--> AeroElectric-List message p
osted by: "Robert L. Nuckolls, III" =0A>=0A>
=0A>>So the bottom line is can the transmitter handle the reflected waves
=0A>>such that when they add up, the end voltage doesn't damage the =0A>>tr
ansmitter components, which of course have maximum voltage and =0A>>power l
imits.- I add power in there because power causes heat and =0A>>component
s can only handle so much maximum temperature.=0A>=0A>- - I'm aware of
no supplier to aviation that does not=0A>- - consider the rare but poss
ible failure of a coax=0A>- - connection . . . it's common practice to
build=0A>- - in protection, robustness or a combination of the=0A>-
==================0A>=0A>=0A>=0A>=0A>=0A>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Amp meter jumps when transmitting |
> >Manufactured lots vary from lot to lot, and some lots may sneak
> through that do not meet specifications but work well until
> "something happens." In >particular, this business of counterfeit
> parts has been plaguing manufacturing for at least two decades now.
Forgive me my friend but we're reaching WAAaaayyyy down into
the worry bucket with this line of reasoning. Once
you open that door . . . where do the caveats end?
Cracked magneto rotors? Contaminated fuel? Bogus rivets?
The world is indeed fraught with risks. Nonetheless,
the vast majority of misadventures in every
venue have nothing to do with parts that fail
to meet published requirements. Adding such
worries to the knowledge base is potential misdirection
of valuable attention from much greater risks.
Bob . . .
________________________________________________________________________________
From: | GTH <gilles.thesee(at)free.fr> |
Subject: | Time delay, flicker filter etc. |
Hi Bob and all,
It's been a long time since my last post on this knowledgeable list.
Our two battery / ABMM / Rotax 914 project has been flying for ten happy
years now, except for one little problem that has kept nagging at us
from the beginning.
The auxiliary battery management module (ABMM) works as advertised,
connecting and disconnecting the aux battery contactor following the
main bus voltage. But at idle, the voltage undergoes rapid fluctuations,
leading to frigthening contactor chattering fits.
As a workaround we ended connecting the aux battery manually.
I was wondering if an easy way of introducing time delay in the voltage
sensing side *or* actuating side of the ABMM could be devised ?
A time constant of 2 second would be adequate I suppose.
Could some variation of the fuel level flicker filter do ?
Thanks in advance for your suggestions, and keep on the good job !
Best regards,
--
Gilles
http://contrails.free.fr
________________________________________________________________________________
From: | Henador Titzoff <henador_titzoff(at)yahoo.com> |
Subject: | Re: Amp meter jumps when transmitting |
You're right that I'm going down a road fraught with all sorts of relativel
y low risk items.- Just trying to explain why an open transmission line m
ight kill a transmitter that's otherwise designed to survive it.- I hope
my explanation of why the voltage could theoretically double at the transmi
tter helped explain to some how this phenomenon happens.=0A=0AHenador Titzo
ff=0A=0A=0A>________________________________=0A> From: "Robert L. Nuckolls,
III" =0A>To: aeroelectric-list(at)matronics.co
m =0A>Sent: Sunday, April 27, 2014 10:50 PM=0A>Subject: Re: AeroElectric-Li
st: Amp meter jumps when transmitting=0A> =0A>=0A>--> AeroElectric-List mes
sage posted by: "Robert L. Nuckolls, III"
=0A>=0A>=0A>> >Manufactured lots vary from lot to lot, and some lots may sn
eak =0A>> through that do not meet specifications but work well until =0A>>
"something happens."- In >particular, this business of counterfeit =0A>>
parts has been plaguing manufacturing for at least two decades now.=0A>=0A
>- - Forgive me my friend but we're reaching WAAaaayyyy down into=0A>
- - the worry bucket with this line of reasoning. Once=0A>- - you o
pen that door . . . where do the caveats end?=0A>- - Cracked magneto ro
tors? Contaminated fuel? Bogus rivets?=0A>- - The world is indeed fraug
ht with risks. Nonetheless,=0A>- - the vast majority of misadventures i
n every=0A>- - venue have nothing to do with parts that fail=0A>- -
to meet published requirements. Adding such=0A>- - worries to the know
ledge base is potential misdirection=0A>- - of valuable attention from
======================0A>=0A>=0A>
=0A>=0A>=0A>
________________________________________________________________________________
Subject: | Re: Amp meter jumps when transmitting |
From: | Dj Merrill <deej(at)deej.net> |
On 04/28/2014 04:22 PM, Henador Titzoff wrote:
> You're right that I'm going down a road fraught with all sorts of
> relatively low risk items. Just trying to explain why an open
> transmission line might kill a transmitter that's otherwise designed to
> survive it. I hope my explanation of why the voltage could
> theoretically double at the transmitter helped explain to some how this
> phenomenon happens.
>
> Henador Titzoff
Your explanation helped me, and matched my limited understanding of how
it works, as well as allowing me to learn more.
Thank you! :-)
-Dj
--
Dj Merrill - N1JOV - VP EAA Chapter 87
Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/
Glastar Flyer N866RH - http://deej.net/glastar/
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Time delay, flicker filter etc. |
>
>A time constant of 2 second would be adequate I suppose.
>Could some variation of the fuel level flicker filter do ?
>
>Thanks in advance for your suggestions, and keep on the good job
Referring to the assembly details in . . .
http://tinyurl.com/nxmo3us
That comparator only has about 0.5% hysteresis . . .
try reducing the value of R108 down to 100K
which will raise the hysteresis by a factor of ~5x
Bob . . .
________________________________________________________________________________
From: | "Alvin Voigt" <iamgodlisten(at)hotmail.com> |
ATS has a crimper on sale for $37.50 with additional BNC die sets for
$14.95. The assortment of terminals and splices included in the kit are
not specifically identified as PDIG, so they my be un-useful for flying
machines. I have been using a crimper for many years that I purchased
from Bob Knuckles that has been quite satisfactory, but does not have
replaceable die sets.
http://www.aircraft-tool.com/shop/detail.aspx?PRODUCT_ID=E500-037&utm_s
ource=ECLIPSE+APRIL&utm_campaign=ECLIPSE+APRIL&utm_medium=email
Alvin Voigt, Ashford, WA
________________________________________________________________________________
From: | "Alvin Voigt" <iamgodlisten(at)hotmail.com> |
Sorry, I meant PIDG terminals and Bob Nuckolls. Past my bed time, I
suppose.
Alvin
From: Alvin Voigt
Sent: Tuesday, April 29, 2014 1:09 AM
Subject: ATS Crimper
ATS has a crimper on sale for $37.50 with additional BNC die sets for
$14.95. The assortment of terminals and splices included in the kit are
not specifically identified as PDIG, so they my be un-useful for flying
machines. I have been using a crimper for many years that I purchased
from Bob Knuckles that has been quite satisfactory, but does not have
replaceable die sets.
http://www.aircraft-tool.com/shop/detail.aspx?PRODUCT_ID=E500-037&utm_s
ource=ECLIPSE+APRIL&utm_campaign=ECLIPSE+APRIL&utm_medium=email
Alvin Voigt, Ashford, WA
________________________________________________________________________________
From: | "Bill S" <docyukon(at)ptcnet.net> |
Subject: | lm7321 substatute |
Bob Can you recomend a substatute for a lm7321 opamp, in a din package? The
sot23 package is just tooooooo small for me to work with. Thanks
Bill S.
________________________________________________________________________________
Subject: | Battery and master contactor - ok to mount horizontally? |
From: | Sacha <uuccio(at)gmail.com> |
Quick question about Battery and contactor installation position:
I am moving my battery aft and am planning to make an installation similar to the example on Bob's website at http://www.aeroelectric.com/articles/Battery_Grounds/Battery_Grounds.html
Except that instead of having the (SVLA) battery upright I want it on its side.
Is that ok? And is it ok to mount the master and starter contactors horizontally
(I'm planning to use rivnuts and bolt them to a horizontal sheet of stainless
steel) instead of using L-shaped tabs to mount them vertically as in the picture?
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Subject: | Re: Battery and master contactor - ok to mount horizontally? |
Mounting the battery on its side and the contactors horizontally is just fi
ne.- It won't affect the operation of either device.=0A=0A=0A=0A=0A______
__________________________=0A From: Sacha <uuccio(at)gmail.com>=0ATo: aeroelec
tric-list =0ASent: Tuesday, April 29, 201
4 6:41 PM=0ASubject: AeroElectric-List: Battery and master contactor - ok t
ha =0A=0AQuick question about Battery and contactor insta
llation position:=0A=0AI am moving my battery aft and am planning to make a
n installation similar to the example on Bob's website at http://www.aeroel
ectric.com/articles/Battery_Grounds/Battery_Grounds.html =0AExcept that ins
tead of having the (SVLA) battery upright I want it on its side. Is that ok
? And is it ok to mount the master and starter contactors horizontally (I'm
planning to use rivnuts and bolt them to a horizontal sheet of stainless s
teel) instead of using L-shaped tabs to mount them vertically as in the pic
=
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: lm7321 substatute |
At 12:50 PM 4/29/2014, you wrote:
>
>Bob Can you recomend a substatute for a lm7321 opamp, in a din
>package? The sot23 package is just tooooooo small for me to work
>with. Thanks Bill S.
What's the application? Can you share a schematic
along with a description of function? There are probably
100+ suitable substitutes with rare exception . . . I
don't want to offer substitute that stumbles over
an exception.
The LM7321 is a fine example of the current state
of op-amp art. Low voltage performance, rail-to-rail
input and outputs, lots of drive capability, etc.
http://tinyurl.com/otlg7je
However, depending on requirements for the circuit
you're crafting, you may NEED few if any of these
stellar features.
Bob . . .
________________________________________________________________________________
From: | "Bill S" <docyukon(at)ptcnet.net> |
Subject: | Re: lm7321 substatute |
At 10:59 AM 12/22/2011, you wrote:
>I am wanting to parllel two Ray Allen RP3 led position indicators useing
>only one POS5 position sensor. RAC said that thay wont work just parelling
>them and that I need to add another position sensor or a switch which I
>would rather not do. Can anyone sudjest an electrical ckt. that would work
>for this? Thanks Bill S.
>
You need a 'buffer-amplifier' between the position
feedback potentiometer and ONE of the two indicators.
The problem with paralleling the two indicators arises
from the fact that they're not a 'high impedance' voltmeter.
The system is calibrated for one pot driving one indicator.
Adding a second indicator doubles the load on the position
signal from the potentiometer.
The 'fix' is to convert one of the indicators into a
high-impedance voltmeter. You need an operational
amplifier with rail-to-rail inputs and outputs. A device
like the LM7321 would probably work.
http://search.digikey.com/us/en/products/LM7321MF%2FNOPB/LM7321MFCT-ND/1878646
Adding this device to the second indicator prevents
it from loading the potentiometer. You need to
fabricate something like this . . .
http://aeroelectric.com/Pictures/Schematics/Ray-Allen_Dual_Indicators.pdf
It could be fabricated on an etched circuit board
that would fit inside a d-sub connector back shell.
Bob . . .
>>Bob Can you recomend a substatute for a lm7321 opamp, in a din package?
>>The sot23 package is just tooooooo small for me to work with. Thanks
>>Bill S.
>
> What's the application? Can you share a schematic
> along with a description of function? There are probably
> 100+ suitable substitutes with rare exception . . . I
> don't want to offer substitute that stumbles over
> an exception.
>
> The LM7321 is a fine example of the current state
> of op-amp art. Low voltage performance, rail-to-rail
> input and outputs, lots of drive capability, etc.
>
> http://tinyurl.com/otlg7je
>
> However, depending on requirements for the circuit
> you're crafting, you may NEED few if any of these
> stellar features.
>
>
> Bob . . .
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
>
________________________________________________________________________________
From: | John <jrevens(at)comcast.net> |
Subject: | Re: Battery and master contactor - ok to mount horizontally? |
Mounting position is definitely a consideration with some contactors.
There are units that are designed for horizontal mounting,
or are position insensitive, but there are others that are not. The
Series 70 White-Rogers units, that have been very commonly
used in aircraft for decades are position sensitive. Here is a link to
some info:
http://www.emersonclimate.com/Documents/White-Rodgers/sell_sheets/R-4003web.pdf
<http://www.emersonclimate.com/Documents/White-Rodgers/sell_sheets/R-4003web.pdf>
This literature recommends dome, or cap, down. Depending on whether the
unit is used as a master or start "solenoid", some
recommend mounting dome up These solenoid/contactors will seem to work
OK either way, but there is more potential wear
and possibility of binding or improper operation if they are operated
horizontally.
/John
/
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Battery and master contactor - ok to mount horizontally? |
At 11:44 AM 4/30/2014, you wrote:
Mounting position is definitely a consideration with some contactors.
There are units that are designed for horizontal mounting, or are
position insensitive, but there are others that are not. The Series
70 White-Rogers units, that have been very commonly used in aircraft
for decades are position sensitive. Here is a link to some info:
http://www.emersonclimate.com/Documents/White-Rodgers/sell_sheets/R-4003web.pdf
This literature recommends dome, or cap, down. Depending on whether
the unit is used as a master or start "solenoid", some
recommend mounting dome up These solenoid/contactors will seem to
work OK either way, but there is more potential wear
and possibility of binding or improper operation if they are operated
horizontally.
We've had some discussion about both alleged
and demonstrated position sensitivity of these
contactors here on the List . . . here is but
one of several dialogs . . .
http://tinyurl.com/p8uv67n
In other discussions we deduced that the W/R
Type 70 is not well suited to starter contactor
service even in the intermittent version. There
are similarly priced contactors optimized for
starter contactor service.
http://tinyurl.com/n9sql7g
http://tinyurl.com/o5turon
As a battery contactor mounted in a location
certain to be 'drip free', a horizontal mounting
doesn't give rise to great concerns. In any
case, concerns for in-flight g-loading of contactors
has no demonstrable foundation in physics or practice.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: lm7321 substatute |
At 10:27 AM 4/30/2014, you wrote:
>
OOOPS! The 7321 was my selection . . . not sure
why I went with SOT23 only except that my head
was probably thinking about packaging in the
dsub housing . . .
Refresh my memory, we ARE talking about a 5v
system? This op amp would do the job
http://tinyurl.com/ol9jm4v
but it's limited to 7.5v max supply voltage.
It IS in stock at Digikey at 0.88 each.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Battery and master contactor - ok to mount |
horizontally?
At 11:55 AM 4/30/2014, you wrote:
>
>
>Hi, Jeff,
>A word of caution for rivnuts: Be sure that you use rivnuts that
>are HARDER than the substrate, in your case stainless
>steel. Rivnuts have a bad habit of loosening in their holes, making
>the bolt nigh onto impossible to unscrew. Don't ask me how I know!
>
>This might be even worse if you use aluminum rivnuts, as there will
>be corrosion between the metals, which will act as a lubricant.
Good catch Jim . . . rivnuts are problematic
If he cannot get at the back side to install
a real 10-32 nutplate, I think I'd fabricate
a scab-on with nutplates to mount the
contactor. The scab plate needs to have sufficient
footprint so that pop-rivets used to fasten
it to the aircraft surface are not under
the contactor's mounting feet.
I would then cut clearance holes in the
aircraft surface for the nutplates and pop-
rivet the scab with a half dozen or so aluminum
rivets.
This is the sure-bet prophylactic against that
gut wrenching experience of having the rivnut
spin in the hole while trying to dismount the
contactor . . . just hate it when that happens!
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Was Battery and master contactor - ok to mount |
horizontally? Now about Rivnuts
At 02:37 PM 4/30/2014, you wrote:
>(Please pardon the hijacking of this thread...)
>
>
>Jim,
>
>I wasn't the original poster on this thread. I think it was
>Sacha. However, speaking of Rivnuts...
>
>I've experienced some of the issues you are talking about. The last
>few times I've used Rivnuts, I put an internal-tooth lockwasher on
>the back side of the Rivnut before squeezing it, so that it gets
>clamped between the work surface and the bulge formed by squeezing.
Nice vaccination against spinning rivnut syndrome
. . . but if you could get at the back side, why not
nutplates?
Bob . . .
________________________________________________________________________________
From: | "Bill S" <docyukon(at)ptcnet.net> |
Subject: | Re: lm7321 substatute |
The opamp should be rated at least 15v min.
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Sent: Wednesday, April 30, 2014 2:19 PM
Subject: Re: AeroElectric-List: lm7321 substatute
>
>
> At 10:27 AM 4/30/2014, you wrote:
>>
>
> OOOPS! The 7321 was my selection . . . not sure
> why I went with SOT23 only except that my head
> was probably thinking about packaging in the
> dsub housing . . .
>
> Refresh my memory, we ARE talking about a 5v
> system? This op amp would do the job
>
> http://tinyurl.com/ol9jm4v
>
> but it's limited to 7.5v max supply voltage.
> It IS in stock at Digikey at 0.88 each.
>
>
> Bob . . .
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
>
________________________________________________________________________________
From: | Jeff Luckey <jluckey(at)pacbell.net> |
Subject: | Re: Was Battery and master contactor - ok to mount |
horizontally? Now about Rivnuts
=0A=0A=0A=0A________________________________=0A From: "Robert L. Nuckolls,
III" =0ATo: aeroelectric-list(at)matronics.com
=0ASent: Wednesday, April 30, 2014 12:42 PM=0ASubject: Re: AeroElectric-Lis
t: Was Battery and master contactor - ok to mount horizontally? Now about
lls, III" =0A=0AAt 02:37 PM 4/30/2014, you w
rote:=0A>(Please pardon the hijacking of this thread...)=0A>=0A>=0A>Jim,=0A
>=0A>I wasn't the original poster on this thread.- I think it was =0A>Sac
ha.- However, speaking of Rivnuts...=0A>=0A>I've experienced some of the
issues you are talking about.- The last =0A>few times I've used Rivnuts,
I put an internal-tooth lockwasher on =0A>the back side of the Rivnut befor
e squeezing it, so that it gets =0A>clamped between the work surface and th
e bulge formed by squeezing.=0A=0A- Nice vaccination against spinning ri
vnut syndrome=0A- . . . but if you could get at the back side, why not
=0A- nutplates?=0A=0AAgree - but that's the big IF - sometimes you just
don't have enough space or access to use nutplates.- (It's just another a
rrow in the "How am I gonna fix this GD thing" quiver.)-- -JL=0A=0A=0A
=
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: lm7321 substatute |
At 03:13 PM 4/30/2014, you wrote:
>
>
>The opamp should be rated at least 15v min.
Okay, this one should work
http://tinyurl.com/llsm37s
Let me know how this works for you . . . I'll
revise my document on the website. I could
also whack out a little ecb that would sit
between the solder-cups on a d-sub and make
it a whole lot easier to package . . .
Bob . . .
________________________________________________________________________________
Subject: | Re: Was Battery and master contactor - ok to mount |
horizontally? Now about Rivnuts
From: | Sacha <uuccio(at)gmail.com> |
> I wasn't the original poster on this thread. I think it was
> >Sacha.
No need to apologize for "high jacking". I've gathered lots of food for thought
which I will now attempt to digest in order to design the battery and contactor
mount. Thank you all.
I wanted to use rivnuts because they would allow me to permanently fix the steel
plate and then bolt things onto it. The rivnuts I was going to use were steel
ones. Of course I wasn't aware of the issues with them coming loose.
I'm also having second thoughts about using a stainless steel base as I just weighed
it and it's 1kg which seems like overkill.
Sacha
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Was Battery and master contactor - ok to mount |
horizontally? Now about Rivnuts
>
>
>I'm also having second thoughts about using a stainless steel base
>as I just weighed it and it's 1kg which seems like overkill.
The SVLA battery is essentially leak proof.
They cannot exude stuff that eats on your
airplane. A tray with 1/2" sides to capture
the battery's footprint is quite sufficient
for a base. A couple of nylon straps, 1" wide
with velcro closures are good for holding it
down in the tray.
You only need to grab the battery with enough
security to withstand a 10g load. For an 18 Ah
battery that's 200 pounds or less. A pair of
1" with velcro closures are good for MUCH more
than this.
Bob . . .
________________________________________________________________________________
From: | Kelly McMullen <kellym(at)aviating.com> |
Subject: | Re: Was Battery and master contactor - ok to mount |
horizontally? Now about Rivnuts
If riveting a nut plate isn't possible, a Clickbond nutplate is next
best thing, unless you cannot get to backside at all.
On 4/30/2014 12:42 PM, Robert L. Nuckolls, III wrote:
>
>
> At 02:37 PM 4/30/2014, you wrote:
>> (Please pardon the hijacking of this thread...)
>>
>>
>> Jim,
>>
>> I wasn't the original poster on this thread. I think it was Sacha.
>> However, speaking of Rivnuts...
>>
>> I've experienced some of the issues you are talking about. The last
>> few times I've used Rivnuts, I put an internal-tooth lockwasher on
>> the back side of the Rivnut before squeezing it, so that it gets
>> clamped between the work surface and the bulge formed by squeezing.
>
> Nice vaccination against spinning rivnut syndrome
> . . . but if you could get at the back side, why not
> nutplates?
>
>
> Bob . . .
>
>
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: Was Battery and master contactor - ok to mount |
horizontally? Now about Rivnuts
At 07:59 PM 4/30/2014, you wrote:
>
>If riveting a nut plate isn't possible, a Clickbond nutplate is next
>best thing, unless you cannot get to backside at all.
I would have suggested that . . . did an article in
Kitplanes a few months ago that spoke to DIY bond-studs.
All versions of this mounting mode disrupt the otherwise
smooth mounting surface under the contactor's mounting
feet.
Bob . . .
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: lm7321 substatute |
At 03:13 PM 4/30/2014, you wrote:
Have you ordered any op-amps yet? I've got
an order going into Digikey this weekend. I
could add some to the list if you're in no
hurry . . .
Bob . . .
________________________________________________________________________________
Subject: | Re: lm7321 substatute |
From: | "Eric M. Jones" <emjones(at)charter.net> |
> Bob Can you recomend a substatute for a lm7321 opamp, in a din package? The sot23
package is just tooooooo small for me to work with. Thanks Bill S.
I want to propose another solution....c'mon bucky! The Swiss could build a watch
between the legs of the SOT-23. I have circuits where the SOT-23 parts are the
BIG ones.
Seriously, soldering tiny parts is a skill that is not hard to master, but you
have to start with--ideally, a nice stereo lab microscope of modest power-- but
any good magnifier that you don't have to hold with a hand will do. Then use
a fine-tip soldering iron, fine tweezers and some fine-gauge solder.
This is ultimately pretty easy to do. Many electrowhizzies are not available in
bigger packages. Everything is shrinking. To work on tiny stuff requires the
right tools.
Good luck.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422661#422661
________________________________________________________________________________
Subject: | Ray Allen RP3 led position indicators |
From: | "Eric M. Jones" <emjones(at)charter.net> |
> I am wanting to parllel two Ray Allen RP3 led position indicators useing
> only one POS5 position sensor. RAC said that thay wont work just parelling
> them and that I need to add another position sensor or a switch which I
> would rather not do. Can anyone suggest an electrical ckt. that would work
> for this? Thanks Bill S.
I predict that trying to convert the potentiometers to drive the RP3 position indicators
if fraught with peril. I have done it and abandoned the idea in favor
of driving the trim box potentiometer with a higher voltage (regulated 12V)
and doing the conversion at the RP3 with a simple 1:12 voltage divider (another
pot).
We have previously mentioned on this site that the problem with the RP3 is that
it expects a MAXIMUM input voltage of 1.2V and each digit is therefore 0.12 volts,
which is below the noise level for several lower of the LEDs.
Years ago. I figured that the real problem was that push buttons had no memory
for position, so I built the True Servo Control for Mac/RAC trim boxes, TSCMR.
You turn a knob...and that's where the trim box sets the trim. Period. The indicator
is the pointer on the knob. You can still use an LED indicator if you
like, but it is not necessary since the knob pointer is the indicator. I don't
supply the knobs or pots. My "Cessna-Type Trim Wheel" used to drive the TSCMR,
but anyone can make a suitable knob and pot. You could even put one inside your
control stick. See attached.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422664#422664
Attachments:
http://forums.matronics.com//files/tscmr_installation_manual_101.pdf
________________________________________________________________________________
From: | rayj <raymondj(at)frontiernet.net> |
Subject: | Re: Was Battery and master contactor - ok to mount |
horizontally? Now about Rivnuts
Another solution to rivnut rotation I saw suggested somewhere is to file
2 points into the hole, making it kind of a diamond shape.
Theoretically, the bulge expands out in to the diamond shape and
prevents rotation.
Haven't actually tried it, but it seems worth investigating.
Raymond Julian
Kettle River, MN
The things we admire in men, kindness and generosity, openness, honesty,
understanding and feeling are the concomitants of failure in our system.
And those traits we detest, sharpness, greed, acquisitiveness, meanness,
egotism and self-interest are the traits of success. And while men
admire the quality of the first they love the produce of the second.
-John Steinbeck, novelist, Nobel laureate (1902-1968)
On 04/30/2014 03:53 PM, Sacha wrote:
>
>
>> I wasn't the original poster on this thread. I think it was
>>> Sacha.
>
> No need to apologize for "high jacking". I've gathered lots of food for thought
which I will now attempt to digest in order to design the battery and contactor
mount. Thank you all.
>
> I wanted to use rivnuts because they would allow me to permanently fix the steel
plate and then bolt things onto it. The rivnuts I was going to use were steel
ones. Of course I wasn't aware of the issues with them coming loose.
>
> I'm also having second thoughts about using a stainless steel base as I just
weighed it and it's 1kg which seems like overkill.
>
> Sacha
>
>
________________________________________________________________________________
From: | koh leh <kohleh(at)yahoo.com> |
Subject: | Re: lm7321 substitute |
Earlier in the thread I saw a mention of a rail to rail input requirement. If that
is still needed, note the common mode input voltage range of Vdd - 1.35 volts
maximum for the TLV27x. Seems to indicate the input range is not really rail
to rail and I'd expect the output to swing hard to the full on supply voltage
whenever the input is within 1.35v of the supply voltage.
Ken
On 30/04/2014 4:35 PM, Robert L. Nuckolls, III wrote:
>
>
> At 03:13 PM 4/30/2014, you wrote:
>>
>>
>> The opamp should be rated at least 15v min.
>
> Okay, this one should work
>
> http://tinyurl.com/llsm37s
>
> Let me know how this works for you . . . I'll
> revise my document on the website. I could
> also whack out a little ecb that would sit
> between the solder-cups on a d-sub and make
> it a whole lot easier to package . . .
________________________________________________________________________________
From: | BobsV35B(at)aol.com |
Subject: | Re: Was Battery and master contactor - ok to mount |
hori...
Good Morning Raymond,
There are keyed RivNuts and there is a tool to make the slot for the key.
I have had good results just carefully filing a slot in which the key will
fit. Works great!
Happy Skies,
Old Bob
In a message dated 5/1/2014 11:13:46 A.M. Central Daylight Time,
raymondj(at)frontiernet.net writes:
--> AeroElectric-List message posted by: rayj
Another solution to rivnut rotation I saw suggested somewhere is to file
2 points into the hole, making it kind of a diamond shape.
Theoretically, the bulge expands out in to the diamond shape and
prevents rotation.
Haven't actually tried it, but it seems worth investigating.
Raymond Julian
Kettle River, MN
The things we admire in men, kindness and generosity, openness, honesty,
understanding and feeling are the concomitants of failure in our system.
And those traits we detest, sharpness, greed, acquisitiveness, meanness,
egotism and self-interest are the traits of success. And while men
admire the quality of the first they love the produce of the second.
-John Steinbeck, novelist, Nobel laureate (1902-1968)
On 04/30/2014 03:53 PM, Sacha wrote:
>
>
>> I wasn't the original poster on this thread. I think it was
>>> Sacha.
>
> No need to apologize for "high jacking". I've gathered lots of food for
thought which I will now attempt to digest in order to design the battery
and contactor mount. Thank you all.
>
> I wanted to use rivnuts because they would allow me to permanently fix
the steel plate and then bolt things onto it. The rivnuts I was going to use
were steel ones. Of course I wasn't aware of the issues with them coming
loose.
>
> I'm also having second thoughts about using a stainless steel base as I
just weighed it and it's 1kg which seems like overkill.
>
> Sacha
>
>
________________________________________________________________________________
From: | Alan Barnett <alansbarnett(at)verizon.net> |
Subject: | Garmin GNS430 wiring |
I'm installing a Garmin GNS 430 in my COZY III. I bought the unit from
an avionics shop. Since I want to install it myself, I requested all
the wires, connectors, etc required. Included were three fuses (2a, 5a
and 10a), one DPDT switch, and four SPDT switches.
I assume the 10a fuse is for the COM power and the 5a fuse is for the
main power, and that the DPDT switch is for both power circuits. Is this
reasonable?
What are the 2a fuse and the SPDT switches for?
Are there really so many switches in a standard installation? Unless
there is a compelling reason, I intend to leave out the switches.
Thanks for your comments.
Alan
________________________________________________________________________________
From: | BobsV35B(at)aol.com |
Subject: | Re: Garmin GNS430 wiring |
Good Afternoon Alan,
You should ask your supplier for a copy of the current install manual. The
dealer can either run off the copy himself or give you the address so you
can download it.. I do not think he is supposed to give you the address, but
there is nothing at all wrong with his supplying you with the most recent
install manual available. I think the most current one is from about March
of 2013.
Is your unit a 430 or a 430W? The install manual will guide you through
the various possibilities and help you make decisions based on how you wish
to use the unit.
Happy Skies,
Old Bob
In a message dated 5/2/2014 2:52:04 P.M. Central Daylight Time,
alansbarnett(at)verizon.net writes:
--> AeroElectric-List message posted by: Alan Barnett
I'm installing a Garmin GNS 430 in my COZY III. I bought the unit from
an avionics shop. Since I want to install it myself, I requested all
the wires, connectors, etc required. Included were three fuses (2a, 5a
and 10a), one DPDT switch, and four SPDT switches.
I assume the 10a fuse is for the COM power and the 5a fuse is for the
main power, and that the DPDT switch is for both power circuits. Is this
reasonable?
What are the 2a fuse and the SPDT switches for?
Are there really so many switches in a standard installation? Unless
there is a compelling reason, I intend to leave out the switches.
Thanks for your comments.
Alan
________________________________________________________________________________
Subject: | Re: Garmin GNS430 wiring |
From: | Justin Jones <jmjones2000(at)mindspring.com> |
I purchased a used one and am in the same boat. I was able to download the G
armin GNC 430 manual online by searching google for it. I will try to post t
he link when I get back to my computer for those interested.
Justin
On May 2, 2014, at 15:33, BobsV35B(at)aol.com wrote:
> Good Afternoon Alan,
>
> You should ask your supplier for a copy of the current install manual. The
dealer can either run off the copy himself or give you the address so you c
an download it.. I do not think he is supposed to give you the address, but t
here is nothing at all wrong with his supplying you with the most recent ins
tall manual available. I think the most current one is from about March of 2
013.
>
> Is your unit a 430 or a 430W? The install manual will guide you through t
he various possibilities and help you make decisions based on how you wish t
o use the unit.
>
> Happy Skies,
>
> Old Bob
>
> In a message dated 5/2/2014 2:52:04 P.M. Central Daylight Time, alansbarne
tt(at)verizon.net writes:
n.net>
>
> I'm installing a Garmin GNS 430 in my COZY III. I bought the unit from
> an avionics shop. Since I want to install it myself, I requested all
> the wires, connectors, etc required. Included were three fuses (2a, 5a
> and 10a), one DPDT switch, and four SPDT switches.
>
> I assume the 10a fuse is for the COM power and the 5a fuse is for the
> main power, and that the DPDT switch is for both power circuits. Is thi
s
> reasonable?
>
> What are the 2a fuse and the SPDT switches for?
>
> Are there really so many switches in a standard installation? Unless
> there is a compelling reason, I intend to leave out the switches.
>
> Thanks for your comments.
>
> Alan
>
>
>
==========================
=========
==========================
=========
==========================
=========
==========================
=========
>
________________________________________________________________________________
Subject: | Re: Garmin GNS430 wiring |
From: | Sacha <uuccio(at)gmail.com> |
I installed mine without switches and I believe this is best unless you are so
restricted with battery capacity that you'd need to turn off the GPS during an
alternator failure.
I've never seen an installation with more than one external switch (usually the
avionics switch, but keep in mind this is a useless carryover from the past,
not to mention a potentially dangerous single point of failure).
> On May 2, 2014, at 21:36, Alan Barnett wrote:
>
> Unless there is a compelling reason, I intend to leave out the switches.
________________________________________________________________________________
Subject: | Re: How do I prevent starter engaged LED from failing? |
From: | "eschlanser" <eschlanser(at)yahoo.com> |
Bob et group,
In wiring a starter engaged annunciator, I am using an off-the-shelf LED fixture
with an appropriate resistor already integrated into it. The resistor is actually
soldered directly to the LED lead inside of the fixture.
The two attached diagrams from the archives differ in how the diode is added.
(I put a 1A inline fuse where both of the attached drawings shows a resistor.)
In either drawing, it won't be possible to place the legs of the resistor outside
of the legs of a diode in my LED circuit with the integrated resistor. Is
that going to be a problem?
Would one circuit drawing be preferred over the other?
Thank you,
Eric Schlanser
Z13/8 project
Lyc O320 with Skytec 12V HT Wound-Field starter and auto style starter contactor
> I think I remember reading if an LED is used instead of a bulb for
> starter engagement indication, that you best add a diode to prevent
> the LED from getting hurt when power is removed from starter motor.
> Where does the diode get placed, in series with the LED or in parallel?
>
>
Either would work . . . but parallel is preferred.
> If answer is in parallel where would the dropping resistor for LED
> get placed, between the legs of the protection diode, or outside?
>
>
Outside
Bob . . .[/quote]
>
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422741#422741
Attachments:
http://forums.matronics.com//files/starter_engaged_warning_lt_248.pdf
http://forums.matronics.com//files/in_line_resistor_6_966.jpg
________________________________________________________________________________
Subject: | Re: How do I prevent starter engaged LED from failing? |
From: | "user9253" <fransew(at)gmail.com> |
If I understand correctly, you are asking if a protection diode has to be connected
inside of the LED fixture at the junction of the LED and integrated resistor.
No it does not. It can be external as in the attached drawing.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422751#422751
Attachments:
http://forums.matronics.com//files/led_207.pdf
http://forums.matronics.com//files/led_102.jpg
________________________________________________________________________________
From: | "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> |
Subject: | Re: How do I prevent starter engaged LED from |
failing?
At 06:40 PM 5/2/2014, you wrote:
>
>Bob et group,
>
> In wiring a starter engaged annunciator, I am using an
> off-the-shelf LED fixture with an appropriate resistor already
> integrated into it. The resistor is actually soldered directly to
> the LED lead inside of the fixture.
>
> The two attached diagrams from the archives differ in how the
> diode is added. (I put a 1A inline fuse where both of the attached
> drawings shows a resistor.) In either drawing, it won't be possible
> to place the legs of the resistor outside of the legs of a diode in
> my LED circuit with the integrated resistor. Is that going to be a problem?
>Would one circuit drawing be preferred over the other?
They are the same. The protection diode is wired
in parallel with the led to clamp off any reverse
voltage transient. The resistor is shown upstream
and close to the monitored power at the starter.
Having this resistor located remotely eliminates
the need for fusing the sense lead.
Suggest you modify the fixture to move the resistor
out to the source end of the wire and add the diode
in parallel with the led.
Bob . . .
________________________________________________________________________________
Subject: | Re: How do I prevent starter engaged LED from failing? |
From: | "eschlanser" <eschlanser(at)yahoo.com> |
Joe,
You correctly understood my question.
Now I must decide whether or not to use your circuit or another fix I came up
with after a good night's rest. Since I already have the inline fuse, I can replace
the LED in my circuit with a tiny incandescent bulb
http://tinyurl.com/kw8usxc
I much appreciate your reply and diagram.
Eric Schlanser
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=422756#422756
March 12, 2014 - May 03, 2014
AeroElectric-Archive.digest.vol-mh