AeroElectric-Archive.digest.vol-ga
August 22, 2006 - August 28, 2006
Lees Summit, MO
matronics.com/Navigator?AeroElectric-List
Hello Bruce,
The flap switch would only be installed on the pilot's stick grip -- not co-pilot
side. Also, the switch will be momentary and mounted on top of the stick
making inadvertent activation difficult.
Bill
Have you considered
what would happen if you or your passenger inadvertently activated the
flap switch while as cruse speed? Normally, it's not a good idea to put switches
on control sticks that if activated at the wrong time could adversely impact
the safety of the aircraft.
Bruce
www.glasair.org
Im planning to install a switch for the flaps in the pilot stick
grip in addition to the standard panel mounted switch that Vans supplies. Can
I simply hook both switches to the same relay(s)? Any suggestions regarding relay
(P/N & source). Thanks in advance for your assistance.
Bill Gill
RV-7 wiring
Lees Summit, MO
matronics.com/Navigator?AeroElectric-List
________________________________________________________________________________
| From: | Denis Walsh <denis.walsh(at)comcast.net> |
| Subject: | Re: RE: Pullable 80A Circuit Breaker |
While I am waiting for the real experts to weigh in, I offer the
following unsubstantiated feeling:
I don't think a cb "senses" either volts or amps. Rather it reacts
to heat, whose generation is better measured in watts which is a
function of both.
I would therefore surmise that the cb in question would be well
within its rated range; however would probably not trip a 14 volt
load until 160 amps.
well, where are the electro-experts now that we need them??
Denis Walsh
On Aug 22, 2006, at 07:06 292080008, glen matejcek wrote:
>
>
>
> Hi Stan-
>
>> I bought one at Sun n Fun only to discover later that it is 28v.
>
> 28V is the maximum system voltage for that CB. The CB you bought
> should be
> fine for your 14V installation.
>
> glen matejcek
> aerobubba(at)earthlink.net
>
>
________________________________________________________________________________
| From: | Dwight Frye <dwight(at)openweave.org> |
| Subject: | Re: Flap switches/relay wiring |
On Tue Aug 22 09:56:28 2006, Robert L. Nuckolls, III wrote :
>[ ... snip ... ]
> Increased complexity of the flap controls that adds
> the relatively un-robust and easy-to-hit stick grip
> switches would not pass muster with the customers,
> managers and regulators I work for.
>
> Flaps are used very sparingly during a flight. Uncontrolled
> operation of flaps under certain conditions are a
> recipe for a very bad day. I'll suggest that the
> simplest wiring with the most robust components
> will minimize probability of an unhappy event.
For what its worth ......
I have a friend with an RV-7 who has a flap switch on his stick grip. It
is on top, and he has _twice_ hit it while fiddling with charts/etc. in
cruise. In both cases he caught it before there was a big problem ..... but
he was NOT happy that it happened in either case. His conclusion is that
the design is not a good one, for him at least.
The flap-switch-on-the-stick idea sounded great to me until I heard my
friend's story. I have decided that for me the flap switch is going on the
panel within a convenient distance from the throttle. Still easy to get to
in the pattern (my hand should be near the throttle most the time then anyway)
and less likely to be hit accidentally. YMMV.
-- Dwight
________________________________________________________________________________
| From: | "Bruce Gray" <Bruce(at)glasair.org> |
| Subject: | Flap switches/relay wiring |
Well, whatever floats your boat. Good Luck! And be careful.
Bruce
www.glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
wgill10(at)comcast.net
Sent: Tuesday, August 22, 2006 10:54 AM
Subject: RE: AeroElectric-List: Flap switches/relay wiring
Hello Bruce,
The flap switch would only be installed on the pilot's stick grip -- not
co-pilot side. Also, the switch will be momentary and mounted on top of
the
stick making inadvertent activation difficult.
Bill
-------------- Original message --------------
From: "Bruce Gray" <Bruce(at)glasair.org>
Have you considered what would happen if you or your passenger
inadvertently
activated the flap switch while as cruse speed? Normally, it's not a
good
idea to put switches on control sticks that if activated at the wrong
time
could adversely impact the safety of the aircraft.
Bruce
www.glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
wgill10(at)comcast.net
Sent: Tuesday, August 22, 2006 9:17 AM
Subject: AeroElectric-List: Flap switches/relay wiring
I'm planning to install a switch for the flaps in the pilot stick grip
in
addition to the standard panel mounted switch that Van's supplies. Can I
simply hook both switches to the same relay(s)? Any suggestions
regarding
relay (P/N & source). Thanks in advance for your assistance.
Bill Gill
RV-7 wiring
Lee's Summit, MO
matronics.com/Navigator?AeroElectric-List
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: RE: Pullable 80A Circuit Breaker |
>
>
>
> Hi Stan-
>
> >I bought one at Sun n Fun only to discover later that it is 28v.
>
>28V is the maximum system voltage for that CB. The CB you bought should be
>fine for your 14V installation.
Glen is correct. I'll amplify his words with the notion
that voltage ratings on switches and breakers are MAXIMUM
level for operating voltage at the cited current level.
There is no practical minimum voltage. See:
http://aeroelectric.com/articles/swtchrat.pdf
While this article speaks specifically to switches,
the same ratings philosophies apply to breakers
that are simply automated switches designed to
sense current.
Bob . . .
________________________________________________________________________________
| From: | Hopperdhh(at)aol.com |
| Subject: | Re: RE: Pullable 80A Circuit Breaker |
Glen,
CB's are rated in volts only to show what kind of circuit they should be
used in. In other words don't use a breaker rated for 28 volts in a 120 volt
circuit. A 28 volt breaker would IMHO be fine for use in a 12-14 volt circuit.
It is in series with the load, so it can only know the current. It has no
way of knowing the voltage or therefore the wattage of the load. It is heat
activated by having a small amount of resistance, and the heating power is
I*I*R. (I is current, and R is resistance.) This causes it to waste a little
power (and voltage) in order to do its job.
Dan Hopper
RV-7A
Playing with electricity since age 2 when I plugged a key into a wall
outlet. Nothing happened so I plugged in another key. I'm told it sent me across
the room. I've been hooked on the stuff ever since!
In a message dated 8/22/2006 11:03:30 A.M. Eastern Daylight Time,
denis.walsh(at)comcast.net writes:
--> AeroElectric-List message posted by: Denis Walsh
While I am waiting for the real experts to weigh in, I offer the
following unsubstantiated feeling:
I don't think a cb "senses" either volts or amps. Rather it reacts
to heat, whose generation is better measured in watts which is a
function of both.
I would therefore surmise that the cb in question would be well
within its rated range; however would probably not trip a 14 volt
load until 160 amps.
well, where are the electro-experts now that we need them??
Denis Walsh
On Aug 22, 2006, at 07:06 292080008, glen matejcek wrote:
> --> AeroElectric-List message posted by: "glen matejcek"
>
>
>
> Hi Stan-
>
>> I bought one at Sun n Fun only to discover later that it is 28v.
>
> 28V is the maximum system voltage for that CB. The CB you bought
> should be
> fine for your 14V installation.
>
> glen matejcek
> aerobubba(at)earthlink.net
>
>
________________________________________________________________________________
| From: | Hopperdhh(at)aol.com |
| Subject: | Re: RE: Pullable 80A Circuit Breaker |
Glen,
Sorry, I should have said Stan at the top. I agree with you completely.
Bob's post came in after I hit send, so I think we are all in agreement.
Dan
In a message dated 8/22/2006 12:02:38 P.M. Eastern Daylight Time,
Hopperdhh(at)aol.com writes:
Glen,
CB's are rated in volts only to show what kind of circuit they should be
used in. In other words don't use a breaker rated for 28 volts in a 120 volt
circuit. A 28 volt breaker would IMHO be fine for use in a 12-14 volt circuit.
It is in series with the load, so it can only know the current. It has no
way of knowing the voltage or therefore the wattage of the load. It is heat
activated by having a small amount of resistance, and the heating power is
I*I*R. (I is current, and R is resistance.) This causes it to waste a little
power (and voltage) in order to do its job.
Dan Hopper
RV-7A
Playing with electricity since age 2 when I plugged a key into a wall
outlet. Nothing happened so I plugged in another key. I'm told it sent me across
the room. I've been hooked on the stuff ever since!
In a message dated 8/22/2006 11:03:30 A.M. Eastern Daylight Time,
denis.walsh(at)comcast.net writes:
--> AeroElectric-List message posted by: Denis Walsh
While I am waiting for the real experts to weigh in, I offer the
following unsubstantiated feeling:
I don't think a cb "senses" either volts or amps. Rather it reacts
to heat, whose generation is better measured in watts which is a
function of both.
I would therefore surmise that the cb in question would be well
within its rated range; however would probably not trip a 14 volt
load until 160 amps.
well, where are the electro-experts now that we need them??
Denis Walsh
On Aug 22, 2006, at 07:06 292080008, glen matejcek wrote:
>
>
>
> Hi Stan-
>
>> I bought one at Sun n Fun only to discover later that it is 28v.
>
> 28V is the maximum system voltage for that CB. The CB you bought
> should be
> fine for your 14V installation.
>
> glen matejcek
> aerobubba(at)earthlink.net
>
>
bsp; --> nbsp; - NEW MATRONICS LIST WIKI -
========================
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
________________________________________________________________________________
| Subject: | Re: RE: Pullable 80A Circuit Breaker |
| From: | "Matt Prather" <mprather(at)spro.net> |
Err.. I am not an expert, but I don't think that is completely correct.
Heat generated is correct, but the heat is generated solely by the current
passing through the CB. The system voltage has no bearing on how much
heat is generated. Draw the circuit and you can see why. The CB goes in
series with the load. Beit a 2V or 200V system, a particular current
through the CB causes a corresponding voltage drop across the CB while the
CB is closed.
The voltage rating is more related to the ability of the CB to open an
operating (overloaded) circuit. The higher the system voltage the harder
it is to open the circuit (break the current) for a given current.
Voltage rating is likely about contact speed and distance (maybe not
both). A larger system voltage implies the need for faster contacts
and/or larger contact distance.
Regards,
Matt-
>
>
> While I am waiting for the real experts to weigh in, I offer the
> following unsubstantiated feeling:
>
> I don't think a cb "senses" either volts or amps. Rather it reacts
> to heat, whose generation is better measured in watts which is a
> function of both.
>
> I would therefore surmise that the cb in question would be well
> within its rated range; however would probably not trip a 14 volt
> load until 160 amps.
>
> well, where are the electro-experts now that we need them??
> Denis Walsh
>
> On Aug 22, 2006, at 07:06 292080008, glen matejcek wrote:
>
>>
>>
>>
>> Hi Stan-
>>
>>> I bought one at Sun n Fun only to discover later that it is 28v.
>>
>> 28V is the maximum system voltage for that CB. The CB you bought
>> should be
>> fine for your 14V installation.
>>
>> glen matejcek
>> aerobubba(at)earthlink.net
>>
>>
>>
>>
>>
>>
>
>
________________________________________________________________________________
| From: | Dwight Frye <dwight(at)openweave.org> |
| Subject: | Re: Flap switches/relay wiring |
On Tue Aug 22 10:53:49 2006, wgill10(at)comcast.net wrote :
>Hello Bruce,
>
>The flap switch would only be installed on the pilot's stick grip -- not
>co-pilot side. Also, the switch will be momentary and mounted on top of
>the stick making inadvertent activation difficult.
One followup note ... while I (strongly!) agree that having the flap
switch on the co-pilot's stick would be bad news, I disagree with the
statement that putting it on top of the stick would make inadvertant
activation difficult.
My friend has his flap switch on the top of the stick in his RV-7, and
(as I said before) has accidentally deployed flaps (BRIEFLY, and only
minimally, before he caught the mistake) at cruise speeds. This was due
to messing with chart books while flying and having them bump the little
momentary switch on top of the stick.
Consider my comments only as food for thought and a story that speaks
to the specific issue under debate. In the end you should clearly just
do what you feel would work for you.
-- Dwight
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
I get them for as little as under 25 cents each in qty of one (15 cents each
for 100). All industrial electronic suppliers stock them in many types and
brands. $30 will get you 100 parts including shipping in some cases. The
cost difference is not significant in the big picture.
Eric provides a value added KIT of parts etc its up to you to convert
convenience for absolute cost. (Eric also posted the exact part number for
those who wanted to get just the diodes from most any source as above)
Relays with internal diodes are available simply because of demand, not for
technical reasons. Engineers resist change and if it seems to work why
change?
Transorbs are better or (no worse in some opinions) and work in 100% of the
cases. Its a "no brainier" for some of us.
While they may not appear to make a difference in a 5 amp resistive load
with a small relay, Transorbs are proven to have a large advantage in
inductive and larger current loads with larger or different type relays.
But so what! Bob has his "repeatable" test of one and is convinced he is
right.
One size (test) does not fit all cases and perhaps its 90% (for diodes) for
the average aircraft but clearly not 99.99% based on MY own lab repeatable
tests.
The entire world, North America, and Europe for example, ALL say the same
thing that Eric referenced about Diodes vs. Transorbs etc. Just who is out
of step here????
There are hundreds in every modern auto. Given the number of autos made each
year and yes Transorbs do cost more than simple diodes why would auto makers
spend millions of $$ every year for them if the diode was as good and they
could save all that money with diodes. Perhaps they know something not
stated on this list??
If you look at the available data including the many references and read and
understand the available info, its far more compelling than appears on the
surface.
Is "good enough" OK if you can get better for little more?
I am unwilling to have another useless debate. It ends up with a lot of
words/heat etc. and no opinion ever gets changed.
Paul
----- Original Message -----
From: "Ernest Christley" <echristley(at)nc.rr.com>
Sent: Tuesday, August 22, 2006 7:02 AM
Subject: AeroElectric-List: Re: MOV's
>
>
>
>>
>>
>>Coil Suppression:
>>
>>Diodes are not the best method today. Not even the second-, third-, or
>>fourth-
>>best method. But in the 1960's they were the way to go.
>>
>>
> In what aspect does the common, sub-$1, available-everywhere diode fall
> short enough to justify paying $30 for your single-source solution?
>
> --
> ,|"|"|, Ernest Christley |
> ----===<{{(oQo)}}>===---- Dyke Delta Builder |
> o| d |o http://ernest.isa-geek.org |
>
>
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
> Coil Suppression:
>
> In what aspect does the common, sub-$1, available-everywhere diode fall
> short enough to justify paying $30 for your single-source solution?
> --
> ,|"|"|, Ernest Christley
Ernest,
See both of the links I posted,
ref: http://relays.tycoelectronics.com/kilovac/appnotes/transients.asp
See: http://www.periheliondesign.com/suppressors/SnapJack.pdf
but especially:
http://relays.tycoelectronics.com/kilovac/appnotes/fig48.asp
You are incorrect on several points-- These are not single sourced. Every manufacturer
of bi-directional Zener transient voltage suppressors seems to have a
trademarked name for these: Transils, Surmetics, Transorbs, TranZorbs, TransGuards,
Mosorbs; the list is endless. We call them SnapJacks. They are 18 Volt 600
Watt axial-lead bi-directional Zener transient voltage suppressors, part number
P6KE18CA.
The kit includes:
(12) P6KE18CA
(24") of suitable heat shrink tubing,
(4) 1/4" faston solder adaptors
(10) 6-8-10 Multistud ring tongue connectors
(2) 1/4" ring tongues
(2) 5/16" ring tongues
(4) Faston tabs rivet or screw mount
(1) Instructions and technical details,
(1) Perihelion Design catalog
(1) Free first-class shipping
My accountant says I lost $xx,xxx on my little business in '04 and will maybe break
even in '05 and '06, due entirely to my Space Shuttle Switch Guards that
I sell to NASA (Perihelion Design parts are in orbit!) and the Military.
Selling little SnapJack kits like this is a money loser no matter how you cut it,
but I get to hang out with the most interesting people. That's worth a lot.
--------
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=56397#56397
________________________________________________________________________________
| From: | Dave N6030X <N6030X(at)DaveMorris.com> |
Ok, so translated into complete neophyte-speak, for the rest of "us",
this means:
"
1. The experts disagree (as they do in high vs low wing)
2. You can use a diode or a transorb, but do use something.
3. Pick whichever you find cheaper and more readily available.
4. A transorb can be wired up either direction, while a diode must be
wired with the correct polarity.
"
Dave Morris
N5UP
At 11:51 AM 8/22/2006, you wrote:
>
>I get them for as little as under 25 cents each in qty of one (15
>cents each for 100). All industrial electronic suppliers stock them
>in many types and brands. $30 will get you 100 parts including
>shipping in some cases. The cost difference is not significant in
>the big picture.
>
>Eric provides a value added KIT of parts etc its up to you to
>convert convenience for absolute cost. (Eric also posted the exact
>part number for those who wanted to get just the diodes from most
>any source as above)
>
>Relays with internal diodes are available simply because of demand,
>not for technical reasons. Engineers resist change and if it seems
>to work why change?
>
>Transorbs are better or (no worse in some opinions) and work in 100%
>of the cases. Its a "no brainier" for some of us.
>
>While they may not appear to make a difference in a 5 amp resistive
>load with a small relay, Transorbs are proven to have a large
>advantage in inductive and larger current loads with larger or
>different type relays.
>
>But so what! Bob has his "repeatable" test of one and is convinced
>he is right.
>
>One size (test) does not fit all cases and perhaps its 90% (for
>diodes) for the average aircraft but clearly not 99.99% based on MY
>own lab repeatable tests.
>
>The entire world, North America, and Europe for example, ALL say the
>same thing that Eric referenced about Diodes vs. Transorbs etc. Just
>who is out of step here????
>
>There are hundreds in every modern auto. Given the number of autos
>made each year and yes Transorbs do cost more than simple diodes why
>would auto makers spend millions of $$ every year for them if the
>diode was as good and they could save all that money with diodes.
>Perhaps they know something not stated on this list??
>
>If you look at the available data including the many references and
>read and understand the available info, its far more compelling than
>appears on the surface.
>
>Is "good enough" OK if you can get better for little more?
>
>I am unwilling to have another useless debate. It ends up with a lot
>of words/heat etc. and no opinion ever gets changed.
>
>Paul
>
>
>----- Original Message ----- From: "Ernest Christley" <echristley(at)nc.rr.com>
>To:
>Sent: Tuesday, August 22, 2006 7:02 AM
>Subject: AeroElectric-List: Re: MOV's
>
>
>>
>>
>>
>>>
>>>
>>>Coil Suppression:
>>>
>>>Diodes are not the best method today. Not even the second-,
>>>third-, or fourth-
>>>best method. But in the 1960's they were the way to go.
>>>
>>In what aspect does the common, sub-$1, available-everywhere diode
>>fall short enough to justify paying $30 for your single-source solution?
>>
>>--
>> ,|"|"|, Ernest Christley |
>>----===<{{(oQo)}}>===---- Dyke Delta Builder |
>> o| d |o http://ernest.isa-geek.org |
>>
>
>
________________________________________________________________________________
| From: | FLYaDIVE(at)aol.com |
| Subject: | Re: Flap switches/relay wiring |
In a message dated 8/22/2006 10:20:11 AM Eastern Standard Time,
Bruce(at)glasair.org writes:
Have you considered what would happen if you or your passenger inadvertently
activated the flap switch while as cruse speed? Normally, it's not a good idea
to put switches on control sticks that if activated at the wrong time could
adversely impact the safety of the aircraft.
Bruce
www.glasair.org
===================================
Yup!
A quick Right Cross!
This is preceded by the Co-Pilots Check List:
1 - Don't say anything.
2 - Don't touch anything.
Barry
"Chop'd Liver"
"Show them the first time, correct them the second time, kick them the third
time."
Yamashiada
________________________________________________________________________________
| From: | FLYaDIVE(at)aol.com |
| Subject: | Re: Flap switches/relay wiring |
In a message dated 8/22/2006 11:05:53 AM Eastern Standard Time,
dwight(at)openweave.org writes:
The flap-switch-on-the-stick idea sounded great to me until I heard my
friend's story. I have decided that for me the flap switch is going on the
panel within a convenient distance from the throttle. Still easy to get to
in the pattern (my hand should be near the throttle most the time then anyway)
and less likely to be hit accidentally. YMMV.
-- Dwight
=================================
Dwight:
Hitting the flap switch is just like hitting the Mic switch. It is something
you learn ... NOT TO DO.
None of us were born knowing how to fly, you just have to make a concuss
effort. In all cases.
It is like flying:
To go DOWN you push down.
To go UP you pull up.
But what has always confused me is ...
If you keep pulling UP you go DOWN?
Go figure!
Barry
"Chop'd Liver"
"Show them the first time, correct them the second time, kick them the third
time."
Yamashiada
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
Comments by your numbers.
1. I only know one "expert" that disagrees with the use of transorbs. I am
sure they are more but the overwhelming majority of my engineering
associates agree with the "true experts in the field" of relays and
contacts etc.
2. Sort of true in most cases. Not usually true with contactor type relays
switching inductive loads for example. There are two issues the coil
inductive kick that must be addressed that affects the driver of the coil
and the relay contacts which can affect the switched load by delays (seldom)
and slow opening which power contactors really have a large delay in many
cases and the duration and magnitude of the slow opening of a large
inductive load can be damaging.
3. Sure quality and use is trumped by price. 5 cents is better than 25
cents. Using the same logic go to your rat shack and get plastic crimp
terminals as they are cheaper and easier to find.
4. Transorbs are both uni-directional and bi-directional. True in one case
and polarity is important in the other.
However a uni-directional transorb is no better than a diode, and is a diode
in that use.
Paul
----- Original Message -----
From: "Dave N6030X" <N6030X(at)DaveMorris.com>
Sent: Tuesday, August 22, 2006 10:52 AM
Subject: Re: AeroElectric-List: Re: MOV's
>
>
> Ok, so translated into complete neophyte-speak, for the rest of "us", this
> means:
>
> "
> 1. The experts disagree (as they do in high vs low wing)
> 2. You can use a diode or a transorb, but do use something.
> 3. Pick whichever you find cheaper and more readily available.
> 4. A transorb can be wired up either direction, while a diode must be
> wired with the correct polarity.
> "
>
> Dave Morris
> N5UP
>
> At 11:51 AM 8/22/2006, you wrote:
>>
>>
>>I get them for as little as under 25 cents each in qty of one (15 cents
>>each for 100). All industrial electronic suppliers stock them in many
>>types and brands. $30 will get you 100 parts including shipping in some
>>cases. The cost difference is not significant in the big picture.
>>
>>Eric provides a value added KIT of parts etc its up to you to convert
>>convenience for absolute cost. (Eric also posted the exact part number for
>>those who wanted to get just the diodes from most any source as above)
>>
>>Relays with internal diodes are available simply because of demand, not
>>for technical reasons. Engineers resist change and if it seems to work why
>>change?
>>
>>Transorbs are better or (no worse in some opinions) and work in 100% of
>>the cases. Its a "no brainier" for some of us.
>>
>>While they may not appear to make a difference in a 5 amp resistive load
>>with a small relay, Transorbs are proven to have a large advantage in
>>inductive and larger current loads with larger or different type relays.
>>
>>But so what! Bob has his "repeatable" test of one and is convinced he is
>>right.
>>
>>One size (test) does not fit all cases and perhaps its 90% (for diodes)
>>for the average aircraft but clearly not 99.99% based on MY own lab
>>repeatable tests.
>>
>>The entire world, North America, and Europe for example, ALL say the same
>>thing that Eric referenced about Diodes vs. Transorbs etc. Just who is out
>>of step here????
>>
>>There are hundreds in every modern auto. Given the number of autos made
>>each year and yes Transorbs do cost more than simple diodes why would auto
>>makers spend millions of $$ every year for them if the diode was as good
>>and they could save all that money with diodes. Perhaps they know
>>something not stated on this list??
>>
>>If you look at the available data including the many references and read
>>and understand the available info, its far more compelling than appears on
>>the surface.
>>
>>Is "good enough" OK if you can get better for little more?
>>
>>I am unwilling to have another useless debate. It ends up with a lot of
>>words/heat etc. and no opinion ever gets changed.
>>
>>Paul
>>
>>
>>----- Original Message ----- From: "Ernest Christley"
>>
>>To:
>>Sent: Tuesday, August 22, 2006 7:02 AM
>>Subject: AeroElectric-List: Re: MOV's
>>
>>
>>>
>>>
>>>
>>>>
>>>>
>>>>Coil Suppression:
>>>>
>>>>Diodes are not the best method today. Not even the second-, third-, or
>>>>fourth-
>>>>best method. But in the 1960's they were the way to go.
>>>>
>>>In what aspect does the common, sub-$1, available-everywhere diode fall
>>>short enough to justify paying $30 for your single-source solution?
>>>
>>>--
>>> ,|"|"|, Ernest Christley |
>>>----===<{{(oQo)}}>===---- Dyke Delta Builder |
>>> o| d |o http://ernest.isa-geek.org |
>>>
>>
>>
>>
>>
>
>
>
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
True for a bi-directional transorb. But just to muddy the waters, I kind
of like the more common uni-directional transorbs. They will still help
with positive spikes (if you believe in positive spikes ;) ). Used
across a contactor coil, they may delay the opening a smidge compared to
a bidirectional transorb, but I suspect that, like the common diode,
they are more effective at preventing negative spikes (if you believe in
negative spikes comining off contactor coils ;) ). It seems to me
that an 18 volt bidirectional transorb may still let negative spikes
through that are large enough to damage electrolytic capacitors and
perhaps solid state devices, if there is no battery in the circuit. I
guess I used diodes on all the contactors and then added a few transorbs
on the b-lead just because I could...
Are automobiles incorporating transorbs within some devices now? I've
never come across one yet that I've noticed.
Ken
> 4. A transorb can be wired up either direction, while a diode must be
> wired with the correct polarity.
> "
________________________________________________________________________________
| From: | "Tony Babb" <tonybabb(at)alejandra.net> |
Dave,
As a neophyte thanks for leading me to the bottom line here - THANK YOU !!
Tony
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Dave
N6030X
Sent: Tuesday, August 22, 2006 10:53 AM
Subject: Re: AeroElectric-List: Re: MOV's
-->
Ok, so translated into complete neophyte-speak, for the rest of "us",
this means:
"
1. The experts disagree (as they do in high vs low wing)
2. You can use a diode or a transorb, but do use something.
3. Pick whichever you find cheaper and more readily available. 4. A transorb
can be wired up either direction, while a diode must be
wired with the correct polarity.
"
Dave Morris
N5UP
At 11:51 AM 8/22/2006, you wrote:
>-->
>
>I get them for as little as under 25 cents each in qty of one (15
>cents each for 100). All industrial electronic suppliers stock them
>in many types and brands. $30 will get you 100 parts including
>shipping in some cases. The cost difference is not significant in
>the big picture.
>
>Eric provides a value added KIT of parts etc its up to you to
>convert convenience for absolute cost. (Eric also posted the exact
>part number for those who wanted to get just the diodes from most
>any source as above)
>
>Relays with internal diodes are available simply because of demand,
>not for technical reasons. Engineers resist change and if it seems
>to work why change?
>
>Transorbs are better or (no worse in some opinions) and work in 100%
>of the cases. Its a "no brainier" for some of us.
>
>While they may not appear to make a difference in a 5 amp resistive
>load with a small relay, Transorbs are proven to have a large
>advantage in inductive and larger current loads with larger or
>different type relays.
>
>But so what! Bob has his "repeatable" test of one and is convinced
>he is right.
>
>One size (test) does not fit all cases and perhaps its 90% (for
>diodes) for the average aircraft but clearly not 99.99% based on MY
>own lab repeatable tests.
>
>The entire world, North America, and Europe for example, ALL say the
>same thing that Eric referenced about Diodes vs. Transorbs etc. Just
>who is out of step here????
>
>There are hundreds in every modern auto. Given the number of autos
>made each year and yes Transorbs do cost more than simple diodes why
>would auto makers spend millions of $$ every year for them if the
>diode was as good and they could save all that money with diodes.
>Perhaps they know something not stated on this list??
>
>If you look at the available data including the many references and
>read and understand the available info, its far more compelling than
>appears on the surface.
>
>Is "good enough" OK if you can get better for little more?
>
>I am unwilling to have another useless debate. It ends up with a lot
>of words/heat etc. and no opinion ever gets changed.
>
>Paul
>
>
>----- Original Message ----- From: "Ernest Christley"
>
>To:
>Sent: Tuesday, August 22, 2006 7:02 AM
>Subject: AeroElectric-List: Re: MOV's
>
>
>>
>>
>>
>>>
>>>
>>>Coil Suppression:
>>>
>>>Diodes are not the best method today. Not even the second-,
>>>third-, or fourth-
>>>best method. But in the 1960's they were the way to go.
>>>
>>In what aspect does the common, sub-$1, available-everywhere diode
>>fall short enough to justify paying $30 for your single-source solution?
>>
>>--
>> ,|"|"|, Ernest Christley |
>>----===<{{(oQo)}}>===---- Dyke Delta Builder |
>> o| d |o http://ernest.isa-geek.org |
>>
>
>
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring |
Barry and all
Some builders I know of even went one step farther : they put the flap
switch IN THE PLACE of the trim switch. Thus they ensure consistent
inadvertent operation at the worst possible time, as often as possible ;-)
One of them even wrote to a flying magazine, to tell how the aircraft
was dangerous, since his wife retracted the flaps during take-off !
>
> Hitting the flap switch is just like hitting the Mic switch. It is
> something you learn ... NOT TO DO.
>
If you have to learn not to actuate the switch, then it is misplaced. In
14 years teaching to fly, I never had to teach not to inadvertently
actuate a correctly place flap lever or switch.
You can also put the MP gauge behind the wheel at the bottom of the left
panel, and the rev counter at the far right, like in some certified
ships. Some aircraft builders take pride at confusing pilots.
And yet, human factors and ergonomics have improved since WW I ;-)))
http://contrails.free.fr/instruments_ergo.php
Best regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
| From: | Brian Lloyd <brian-yak(at)lloyd.com> |
| Subject: | Flap switches/relay wiring) |
A lot of people seem to want to move functions onto their stick or their
throttle. I would counsel some thought about how you use that function
before you rush to put it on your stick.
The first question is; how much do you use that function? One of the
popular functions to put on the stick seems to be the IDENT function of
the transponder. How often does ATC ask you to squawk IDENT? Not very
often. How hard is it to reach over and press the ident button on the
xpdr? Probably not too hard. An IDENT button on your stick or yoke
requires you do add wiring and a switch. How much is that likely to gain
you in terms of ease of use? I bet that the total amount of effort
required to push the IDENT button every time ATC asks you for the life
of your airplane is less than the time it will take you to wire the
switch. Not a great return on investment.
Now, about the flaps. Again, this is not something you are going to be
using over and over again in one flight. You are going to use it once or
twice per flight. Again, no big impact to have to move your hand to a
flap switch on the panel or near your throttle.
Likewise something like that radio active/standby frequency toggle.
Since you have to put your hand up to the radio to change the frequency
anyway, you may as well press the button to toggle between active and
standby.
So think about the kinds of things you use over and over again in
flight. The short list that comes to mind:
1. radio PTT
2. intercom PTT
3. speed brakes
4. trim
5. weapons select
6. weapons release
There just isn't a whole lot more you are going to use enough to justify
putting it on the stick or throttle so maybe you just want to keep it
simple.
Brian
________________________________________________________________________________
| From: | <chaztuna(at)adelphia.net> |
| Subject: | Re: Flap switches/relay wiring) |
---- Brian Lloyd wrote:
>
> A lot of people seem to want to move functions onto their stick or their
> throttle. I would counsel some thought about how you use that function
> before you rush to put it on your stick.
>
> The first question is; how much do you use that function? One of the
> popular functions to put on the stick seems to be the IDENT function of
> the transponder. How often does ATC ask you to squawk IDENT? Not very
> often. How hard is it to reach over and press the ident button on the
> xpdr? Probably not too hard. An IDENT button on your stick or yoke
> requires you do add wiring and a switch. How much is that likely to gain
> you in terms of ease of use? I bet that the total amount of effort
> required to push the IDENT button every time ATC asks you for the life
> of your airplane is less than the time it will take you to wire the
> switch. Not a great return on investment.
>
> Now, about the flaps. Again, this is not something you are going to be
> using over and over again in one flight. You are going to use it once or
> twice per flight. Again, no big impact to have to move your hand to a
> flap switch on the panel or near your throttle.
>
> Likewise something like that radio active/standby frequency toggle.
> Since you have to put your hand up to the radio to change the frequency
> anyway, you may as well press the button to toggle between active and
> standby.
>
> So think about the kinds of things you use over and over again in
> flight. The short list that comes to mind:
>
> 1. radio PTT
> 2. intercom PTT
> 3. speed brakes
> 4. trim
> 5. weapons select
> 6. weapons release
>
> There just isn't a whole lot more you are going to use enough to justify
> putting it on the stick or throttle so maybe you just want to keep it
> simple.
>
> Brian
Listers,
I suggest that having radio station Flip/Flop and Station Scan switch ( a single
pole double throw momentary switch) is a very useful item to have on the stick.
If the radio stack is located away from the co-pilot, it is a necessity for
them.
Charlie Kuss
________________________________________________________________________________
| From: | <chaztuna(at)adelphia.net> |
| Subject: | Re: Flap switches/relay wiring) |
---- Brian Lloyd wrote:
>
> A lot of people seem to want to move functions onto their stick or their
> throttle. I would counsel some thought about how you use that function
> before you rush to put it on your stick.
>
> The first question is; how much do you use that function? One of the
> popular functions to put on the stick seems to be the IDENT function of
> the transponder. How often does ATC ask you to squawk IDENT? Not very
> often. How hard is it to reach over and press the ident button on the
> xpdr? Probably not too hard. An IDENT button on your stick or yoke
> requires you do add wiring and a switch. How much is that likely to gain
> you in terms of ease of use? I bet that the total amount of effort
> required to push the IDENT button every time ATC asks you for the life
> of your airplane is less than the time it will take you to wire the
> switch. Not a great return on investment.
>
> Now, about the flaps. Again, this is not something you are going to be
> using over and over again in one flight. You are going to use it once or
> twice per flight. Again, no big impact to have to move your hand to a
> flap switch on the panel or near your throttle.
>
> Likewise something like that radio active/standby frequency toggle.
> Since you have to put your hand up to the radio to change the frequency
> anyway, you may as well press the button to toggle between active and
> standby.
>
> So think about the kinds of things you use over and over again in
> flight. The short list that comes to mind:
>
> 1. radio PTT
> 2. intercom PTT
> 3. speed brakes
> 4. trim
> 5. weapons select
> 6. weapons release
>
> There just isn't a whole lot more you are going to use enough to justify
> putting it on the stick or throttle so maybe you just want to keep it
> simple.
>
> Brian
Listers,
I suggest that having radio station Flip/Flop and Station Scan switch ( a single
pole double throw momentary switch) is a very useful item to have on the stick.
If the radio stack is located away from the co-pilot, it is a necessity for
them.
Charlie Kuss
________________________________________________________________________________
| From: | FLYaDIVE(at)aol.com |
| Subject: | Re: Flap switches/relay wiring |
In a message dated 8/22/06 5:13:32 PM Eastern Daylight Time,
Gilles.Thesee@ac-grenoble.fr writes:
> If you have to learn not to actuate the switch, then it is misplaced. In
> 14 years teaching to fly, I never had to teach not to inadvertently
> actuate a correctly place flap lever or switch.
> You can also put the MP gauge behind the wheel at the bottom of the left
> panel, and the rev counter at the far right, like in some certified
> ships. Some aircraft builders take pride at confusing pilots.
>
> And yet, human factors and ergonomics have improved since WW I ;-)))
> http://contrails.free.fr/instruments_ergo.php
>
> Best regards,
> Gilles Thesee
> Grenoble, France
> http://contrails.free.fr
==========================
Gill:
You are right! And to that I would add the problem twin Beech have with the
placement of the Gear switch (saw that accident). And how may of your
students have pulled MIXTURE instead if throttle?
But, I'd bet the fellow did not brief his wife on the Copilot Check List.
Take a look in current military aircraft ... Notice the MANY safety switches?
F-4 use to pickle their entire Su-21 rocket pod because their gloves got
caught on the switch ... Whoops Did I do that!
There was an accident at a local airport ...
Plane - C-150
Pilot - CFI
Passenger - TV Cameraman
The accident happened on take off ... As the plane was climbing out and
luckily the plane did not go past the end of the runway. Lucky only because the
end
of the runway was a major 4 lane highway. The passenger moved his camera bag
right on top of the (panel mounted) flap switch ... C-150's don't climb well
with 40 Deg of flaps! All survived, but I'd bet that CFI does not get a job
with a major airline.
This leads to the professor's quote: "The only way to make something idiot
proof, is to remove the idiot."
Barry
"Chop'd Liver"
"Show them the first time, correct them the second time, kick them the third
time."
Yamashiada
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>Dave,
>
>As a neophyte thanks for leading me to the bottom line here - THANK YOU !!
>
>Tony
>
>-----Original Message-----
>From: owner-aeroelectric-list-server(at)matronics.com
>[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Dave
>N6030X
>Sent: Tuesday, August 22, 2006 10:53 AM
>To: aeroelectric-list(at)matronics.com
>Subject: Re: AeroElectric-List: Re: MOV's
>
>
>-->
>
>Ok, so translated into complete neophyte-speak, for the rest of "us",
>this means:
>
>"
>1. The experts disagree (as they do in high vs low wing)
>2. You can use a diode or a transorb, but do use something.
>3. Pick whichever you find cheaper and more readily available.
>4. A transorb can be wired up either direction, while a diode must be
> wired with the correct polarity.
Actually, Transorbs come in two flavors . . . uni-polar
and bi-polar. Something else to keep in mind is that
a Transorb is just a special variant of a zener diode.
Zeners are intended for continuous duty, relatively hi
energy dissipation, voltage regulation or limiting tasks
and have sharper regulation characteristics than Transorbs
which are optimized for short duration, relatively hi power
but low energy clamping tasks. They have a might higher
dynamic resistance than zeners while performing their
"regulation" function.
Many companies supply relays with diodes and/or diode-zener
combinations already installed inside their product. For
example, the S702-1 intermittent duty contactor we used to
sell has the coil suppression diode built in.
If one checks out the data sheet at:
http://www.azettler.com/pdfs/technical_notes.pdf
on page 6 we see various coil suppression techniques
discussed. Incidently, the "varistor" technique
at the bottom of the page is the MOV technique we've
been discussing.
Note that the diode-only technique is shown along with
a notice that it offers long delays for release
time which is consistent with the experimental data
I posted earlier. Note further that there is no
suggestion that this technique not be used in favor
of another technique. One presumes that choices are
driven by differences in circuit performance and not
by a desire to minimize stresses harmful to the
relay.
On the same page we see the zener (transorb)-diode
technique. Note that a diode is used with a zener
because it too is a uni-polar device. The diode is
necessary to prevent forward conduction of the zener
during times the relay is energized but still allows
the zener to do its voltage clamping thing during
coil-spike-time.
One could, of course, use the bi-polar Transorb
in place of a zener (transorb)-diode network.
Bob . . .
________________________________________________________________________________
| From: | "Peter Pengilly" <peter(at)sportingaero.com> |
| Subject: | Flap switches/relay wiring) |
>So think about the kinds of things you use over and over again in
>flight. The short list that comes to mind:
>
>1. radio PTT
>2. intercom PTT
>3. speed brakes
>4. trim
>5. weapons select
>6. weapons release
>There just isn't a whole lot more you are going to use enough to
justify
>putting it on the stick or throttle so maybe you just want to keep it
>simple.
Well, if we're going off on this tack I would add
-Master mode select (air-to-ground, air-to-air, nav, approach)
-AAM cage/uncage
-Waypoint step up
-Weapon aiming sensor select
-Sensor slew/zoom/track/scan
-Autopilot/stabs disconnect
-Chaff/flare release
What's appropriate to small airplanes (as well as those Brian
mentioned)?
Autopilot disconnect
Possibly waypoint step up if your GPS/EFIS allows
Where's the flap switch? On the panel in front of the throttle
Radio tune/flip flop? On the up front controller (just below the HUD)
Waypoint insert/select? Up front controller
So for those actions that are done a lot (radio tune), where you have to
look in, put the box just below the glare shield so that you move your
eyes a minimum distance.
Might as well learn something from all those taxpayer $$$!
BTW some 2 seat Pitts' had the PTT on the throttle - always seemed like
a good idea if you expect to have an autopilot in the right seat.
Pete
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
Comments by your numbers.
1. I only know one "expert" that disagrees with the use of transorbs. I am
sure they are more but the overwhelming majority of my engineering
associates agree with the "true experts in the field" of relays and
contacts etc.
Who's claiming to be an expert? Please cite the writings
of any other individual who has measured, illustrated and
explained variabilities and their effects in the manner
which I've offered. The name, job title and organization
of any such individual are unimportant. The numbers and
explanations are. Good data and experimental technique
stands by itself because it (1) makes sense and/or (2)
is easily supported (or refuted) by repeating the experiment.
I can demonstrate at least three cases in the past 8 years
where the best that some big-name companies could bring to
bear on high dollar problems was insufficient to the task.
Instead of getting their fast-turn advice on how best to
deduce failures of their products, it took me months and
in one case years to figure it out for myself. In the end,
I knew more about some aspects of their product than they
did.
2. Sort of true in most cases. Not usually true with contactor type relays
switching inductive loads for example. There are two issues the coil
inductive kick that must be addressed that affects the driver of the coil
and the relay contacts which can affect the switched load by delays
(seldom) and slow opening which power contactors really have a large delay
in many cases and the duration and magnitude of the slow opening of a large
inductive load can be damaging.
If I read this correctly, you're citing the occasional
system performance issue where a 12 mS dropout delay
is okay but a 60+ mS delay causes problems. Yes, I've
had to deal with a few systems where multiple relays could
get into operating "races" and produce unpredictable and
unsatisfactory performance. I know of no situation in OBAM
aviation where this could be an issue.
However, in the last sentence you seem to be speaking of
contact spreading velocity which I've shown is mildly
affected by the form of coil spike suppression.
3. Sure quality and use is trumped by price. 5 cents is better than 25
cents. Using the same logic go to your rat shack and get plastic crimp
terminals as they are cheaper and easier to find.
Price has nothing to do with the design points under
discussion. MOVs were attractive to me early on in spite
of their price BECAUSE they were bi-directional devices.
I reasoned that use of the MOV would prevent the occasional
accidental mis-wiring that is possible with the decidedly
uni-directional nature of diodes. However, they did not
perform as well as diodes for the purpose of reducing stress
on the controlling switch. Further, they were hard to find
in very low conduction voltage ratings.
I abandoned them in my writings after a few years in
favor of readily available, lower cost, better performing,
plain vanilla diode.
4. Transorbs are both uni-directional and bi-directional. True in one case
and polarity is important in the other.
However a uni-directional transorb is no better than a diode, and is a
diode in that use.
In fact, you cannot use a uni-directional Transorb (or
plain-vanilla zener) unless combined with a diode to
prevent forward conduction as shown in multitudes of catalogs
and literature on relays.
Paul
At 11:51 AM 8/22/2006, you wrote:
I get them for as little as under 25 cents each in qty of one (15 cents
each for 100). All industrial electronic suppliers stock them in many types
and brands. $30 will get you 100 parts including shipping in some cases.
The cost difference is not significant in the big picture.
Agreed. Let us leave cost out of it.
Eric provides a value added KIT of parts etc its up to you to convert
convenience for absolute cost. (Eric also posted the exact part number for
those who wanted to get just the diodes from most any source as above)
Relays with internal diodes are available simply because of demand, not for
technical reasons. Engineers resist change and if it seems to work why change?
???? Really. You don't speak very highly of engineers. Stuck
in ruts (do they never seek to broaden their horizons?) Further,
they're willing to accept anything that "seems" to work. Don't
you think it's incumbent upon the savvy engineer to KNOW how
and why things work and not rely on mortal perception? Perhaps
I benefited from not having finished school if I avoided that
upper level class: Ruts and Perceptions 425 - Recipes for
Failure.
Transorbs are better or (no worse in some opinions) and work in 100% of the
cases. Its a "no brainier" for some of us.
How are they "better"? I've never said that they SHOULD
NOT be used or that they were somehow inferior. The only
thing I've said and demonstrated was that there is no
measurable value FOR using them.
The difference between NO suppression (open circuit) and
the most aggressive suppression (diode) was a spread of
10% in arc-time during contact opening. A diode-transorb
combo would fall somewhere in between. This means that
the delta for diode-transorb versus diode-only could be
as little as 1% and maybe as much a 9% . . . that was
the point of the experiment, to put some bounds on a
spread. Further, it's the only claim being made from
analysis of the data.
While they may not appear to make a difference in a 5 amp resistive load
with a small relay, Transorbs are proven to have a large advantage in
inductive and larger current loads with larger or different type relays.
Please cite the experiments and the resulting data.
Keep in mind that off-the-shelf relays of ALL sizes
are available with nothing, diode-zener and diode
only coil suppression. If one technique were so
decidedly favorable over another technique, why
hasn't the relay and contactor industry all jumped
onto one bandwagon as your "entire world" citation
below suggests they should?
But so what! Bob has his "repeatable" test of one and is convinced he is right.
I gathered data on one relay and tested three others of various
sizes from 2 to 30 or so amps. The measured results with respect
to effects on contact spreading velocity were similar. If the test
was poorly crafted then it should be no big deal to demonstrate
my error.
One size (test) does not fit all cases and perhaps its 90% (for diodes) for
the average aircraft but clearly not 99.99% based on MY own lab repeatable
tests.
Please share the data of your tests. What size relay would
you like to see data on? I have some real honkers. I think I
could do a 400A interrupt experiment for you. Let us compare
notes.
The entire world, North America, and Europe for example, ALL say the same
thing that Eric referenced about Diodes vs. Transorbs etc. Just who is out
of step here????
Please cite the literature. You've cited applications literature
on Transorbs before that was shown to be overstated or when it
came to over-voltage and load-dump mitigation. You once advocated
a generous sprinkling of Transorbs on the bus . . . one for every
breaker as I recall. The Transorb is a high power, low energy
device well suited for mitigating short duration events . . .
lightning strikes and ESD. I'm well aware of their usefulness. I
stuck an array of Transorbs on an electro-whizzy just this weekend
so that I could pass and ESD test in the lab tomorrow morning.
At the same time, others here on the list have shown that the
Transorb is not suited to a load-dump mitigation without
deliberate impedance limiting of the energy source (just
like the manual says). In this discussion, we're definitely in
the short duration, low energy realm where a Transorb thrives.
But I'll say again, I'm not campaigning against Transorbs for
this application. I'm only stating that there's no compelling
evidence support superior performance over the lowly diode for
coil suppression when it comes to fending off the contact-eating
gremlins.
There are hundreds in every modern auto. Given the number of autos made
each year and yes Transorbs do cost more than simple diodes why would auto
makers spend millions of $$ every year for them if the diode was as good
and they could save all that money with diodes. Perhaps they know something
not stated on this list??
Perhaps you have special knowledge of the reasoning behind their
use? Yes, we use hundreds of them on airplanes too, but they're
not used on large contactors in lieu of diodes . . . for the
reasons I've cited.
If you look at the available data including the many references and read
and understand the available info, its far more compelling than appears on
the surface.
Let us not talk about "surface" or "appearances". How about
physics of test setups and numbers derived therefrom.
Is "good enough" OK if you can get better for little more?
I am unwilling to have another useless debate. It ends up with a lot of
words/heat etc. and no opinion ever gets changed.
It is not my wish to convince you or anyone else of anything
sir. It's my intent to explain things and support my explanations
with demonstrable fact and logical conclusions based on those
facts. If I am in error, nobody would be happier to know the
nature of the error than I. Go to the lab sir. Show us the
data you've collected. I need to know how I screwed up. You
name the test conditions and I'll repeat the test so we can
compare results. This is where the debate becomes useful . . .
not to you or I but to those who choose to read it and
deduce facts of the matter for themselves.
Bob . . .
---------------------------------------------------------
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
---------------------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>True for a bi-directional transorb. But just to muddy the waters, I kind
>of like the more common uni-directional transorbs. They will still help
>with positive spikes (if you believe in positive spikes ;) ). Used across
>a contactor coil, they may delay the opening a smidge compared to a
>bidirectional transorb, but I suspect that, like the common diode, they
>are more effective at preventing negative spikes (if you believe in
>negative spikes comining off contactor coils ;) ). It seems to me that
>an 18 volt bidirectional transorb may still let negative spikes through
>that are large enough to damage electrolytic capacitors and perhaps solid
>state devices, if there is no battery in the circuit. I guess I used
>diodes on all the contactors and then added a few transorbs on the b-lead
>just because I could...
>
>Are automobiles incorporating transorbs within some devices now? I've
>never come across one yet that I've noticed.
>
>Ken
>
>>4. A transorb can be wired up either direction, while a diode must be
>>wired with the correct polarity.
>>"
A contactor coil can generate spikes of either polarity. It
depends on how you switch it. Here's a trace I took off the coil
of a Cole-Hersee battery contactor with no coil suppression.
I dug through the archives and found some more data on devices
common to the OBAM aviation electrical systems. See:
http://www.aeroelectric.com/Pictures/Curves/CH_Bus_Noise_w_0p1_Cap.gif
Here you see a 300+ volt POSITIVE spike because the controlling switch
(battery master) is in the ground lead. Note that with as little as
0.1 uF capacitor on the supply plus whatever the bench supply
(3A regulated) impedance was, the spike noise coupled to the bus
was on the order of one or two volts high. And this may have been
a test setup artifact (meaning smaller than observed). The point of
this setup was to show that coil spikes are a danger only to the
controlling device (in this case, battery master switch) and NOT
to other devices on the bus. These spikes DO NOT propagate about
the system on the lookout for vulnerable electro-whizzies.
The next trace . . .
http://www.aeroelectric.com/Pictures/Curves/CH_w_120_Ohm.gif
shows the coil suppression benefits of a simple resistor. In this
case, 120 ohms. The spike is notably smaller, only 90 volts
or so and again, the spike coupled to the bus was tiny by
comparison and probably not "real". Note the 22 mS release
time for the contactor. The next trace . . .
http://www.aeroelectric.com/Pictures/Curves/CH_w_1n5400.gif
shows what happens with the plain diode spike suppressor.
Note the very slight upward inflection of trace #2 above
bus voltage where the coil energy is staining against the
diode's forward voltage drop as positive going spike is
clamped off. Note the 75 mS release time. The next trace . . .
http://www.aeroelectric.com/Pictures/Curves/CH_w_2x18v_Transorbs.gif
shows the results of a pair of 18v Transorbs (or zeners)
hooked back to back to emulate the bi-directional device.
Here the spike clamps off at an expected level of about 18 volts
above bus voltage and we see a release time of about 14 mS.
The next trace . . .
http://www.aeroelectric.com/Pictures/Curves/Cole-Hersee_without_Diode.gif
Shows a Cole-Hersee contactor release time ploted at some
other time without a diode but this time, I captured the
release time of 11 mS. The next trace . . .
http://www.aeroelectric.com/Pictures/Curves/Cole-Hersee_with_Diode.gif
is for the same relay and shows a 53 mS release time, again
about 5x the no-diode time noted above. This data is proprotionally
consistant with numbers I posted for the smaller relay
earlier. Note also that one experiment with the CH contactor
and diode yielded a 75 mS release time while the second
was only 53 mS. This variability is to be expected and is
driven by many factors including contactor temperature and
manufacturing variables. The effects of any one suppression
technique can be accurately compared only when all techniques
are used on the same contactor and done with some effort to
keep the contactor temperature constant for each experiment.
Note that NONE of these traces went to the issue of contact
spreading velocity and resulting arc durations . . . only changes
in release time for the various techniques with a peripheral look
at spike propagation to the bus.
This series of traces serves to illustrate only the variability
of release time which a number of articles have mistakenly
assumed that proportionate decreases in contact spreading
velocity automatically follow. I'll suggest that the
assumed proportionality does not exist and that their is no
demonstrable advantage for using one suppression technique over
another in terms of performance. That suggests we're free to
choose techniques based on price. The plain vanilla diode is
hard to beat for price and wide spread availability. However,
I'd be delighted to be shown wrong if my suggestion is in error.
Bob . . .
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
I cannot let this get past as your statement is in fact TOTALLY technically
incorrect (vs opinions).
Below requests for links must exclude your own as they need to be unbiased!
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Tuesday, August 22, 2006 7:32 PM
Subject: Re: AeroElectric-List: Re: MOV's
> In fact, you cannot use a uni-directional Transorb (or
> plain-vanilla zener) unless combined with a diode to
> prevent forward conduction as shown in multitudes of catalogs
> and literature on relays.
Please tell the LIST (specific link please) where a 50V uni-directional
Transorb device (properly connected) is different from a 50v diode in coil
supression or forward conduction for that matter.
Of course if you use a Transorb alone as a diode its no better than a diode
so that configuration is not addressed.
Both forward conduct and both block at voltages under 50V. Heck the common
50V Zener is the same in that respect.
Both also conduct in both directions if the breakdown V is exceeded. I
thought we agreed the Transorb is like a zener with the special
charactericts (specifically its designed for HUGE " zener current" for a
very short time and perhaps 10,000 times faster as the normal Zener which is
not capable of fast enough response to perform the function of transient
supression.
Please show me ANY reference that supports your statement (link please) that
a single transorb is NOT exactly like a diode when used in relay coil
supression just by its self and PROPERLY connected to work as a diode. Or a
Zener for that matter.
In a pinch a zener or a uni-directional transorb can act as a diode in non
critical circuits as long as the Voltage rating is observed.
Finally is there (in the industry) any statements that state that a diode is
BETTER than a Transorb as you suggest?? (Please supply a link) I sure have
not seen any and I have looked as has Eric and together we have found many
to look at here and in Europe. EVERY reference we have found stated the
diode is not as good as the transorb, or (Zener/diode combination). In fact
the LEAST preferred part on EVERY list is the diode. Not that diodes work OK
in most applications usually discussed on this list
Paul
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
As I have stated in my original post which you (apparently do not want to
respond to) I will not get into a debate with you ever again (actually on
ANY subject) and this subject (transorbs) has been debated between us
starting nearly 10 years ago.
If you truly are interested in the reasons (pros and cons) of the various
types of coil suppression please consider reviewing the references Eric
posted as your reference had little info other than to illustrate the types
of suppression relay delays. Yes (as you have stated) the total circuit (not
just the coil) drives the suppression method and Transorbs always work and
diodes only usually work.
I will not respond to your comments below (however erroneous some may be) as
there is no point.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Tuesday, August 22, 2006 7:32 PM
Subject: Re: AeroElectric-List: Re: MOV's
>
>
>
>
>
> Comments by your numbers.
>
> 1. I only know one "expert" that disagrees with the use of transorbs. I am
> sure they are more but the overwhelming majority of my engineering
> associates agree with the "true experts in the field" of relays and
> contacts etc.
>
> Who's claiming to be an expert? Please cite the writings
> of any other individual who has measured, illustrated and
> explained variabilities and their effects in the manner
> which I've offered. The name, job title and organization
> of any such individual are unimportant. The numbers and
> explanations are. Good data and experimental technique
> stands by itself because it (1) makes sense and/or (2)
> is easily supported (or refuted) by repeating the experiment.
>
> I can demonstrate at least three cases in the past 8 years
> where the best that some big-name companies could bring to
> bear on high dollar problems was insufficient to the task.
> Instead of getting their fast-turn advice on how best to
> deduce failures of their products, it took me months and
> in one case years to figure it out for myself. In the end,
> I knew more about some aspects of their product than they
> did.
>
>
> 2. Sort of true in most cases. Not usually true with contactor type relays
> switching inductive loads for example. There are two issues the coil
> inductive kick that must be addressed that affects the driver of the coil
> and the relay contacts which can affect the switched load by delays
> (seldom) and slow opening which power contactors really have a large delay
> in many cases and the duration and magnitude of the slow opening of a
> large inductive load can be damaging.
>
> If I read this correctly, you're citing the occasional
> system performance issue where a 12 mS dropout delay
> is okay but a 60+ mS delay causes problems. Yes, I've
> had to deal with a few systems where multiple relays could
> get into operating "races" and produce unpredictable and
> unsatisfactory performance. I know of no situation in OBAM
> aviation where this could be an issue.
>
> However, in the last sentence you seem to be speaking of
> contact spreading velocity which I've shown is mildly
> affected by the form of coil spike suppression.
>
>
> 3. Sure quality and use is trumped by price. 5 cents is better than 25
> cents. Using the same logic go to your rat shack and get plastic crimp
> terminals as they are cheaper and easier to find.
>
> Price has nothing to do with the design points under
> discussion. MOVs were attractive to me early on in spite
> of their price BECAUSE they were bi-directional devices.
> I reasoned that use of the MOV would prevent the occasional
> accidental mis-wiring that is possible with the decidedly
> uni-directional nature of diodes. However, they did not
> perform as well as diodes for the purpose of reducing stress
> on the controlling switch. Further, they were hard to find
> in very low conduction voltage ratings.
>
> I abandoned them in my writings after a few years in
> favor of readily available, lower cost, better performing,
> plain vanilla diode.
>
>
> 4. Transorbs are both uni-directional and bi-directional. True in one case
> and polarity is important in the other.
>
> However a uni-directional transorb is no better than a diode, and is a
> diode in that use.
>
> In fact, you cannot use a uni-directional Transorb (or
> plain-vanilla zener) unless combined with a diode to
> prevent forward conduction as shown in multitudes of catalogs
> and literature on relays.
>
> Paul
>
> At 11:51 AM 8/22/2006, you wrote:
>
>
> I get them for as little as under 25 cents each in qty of one (15 cents
> each for 100). All industrial electronic suppliers stock them in many
> types and brands. $30 will get you 100 parts including shipping in some
> cases. The cost difference is not significant in the big picture.
>
> Agreed. Let us leave cost out of it.
>
>
> Eric provides a value added KIT of parts etc its up to you to convert
> convenience for absolute cost. (Eric also posted the exact part number for
> those who wanted to get just the diodes from most any source as above)
>
> Relays with internal diodes are available simply because of demand, not
> for technical reasons. Engineers resist change and if it seems to work why
> change?
>
> ???? Really. You don't speak very highly of engineers. Stuck
> in ruts (do they never seek to broaden their horizons?) Further,
> they're willing to accept anything that "seems" to work. Don't
> you think it's incumbent upon the savvy engineer to KNOW how
> and why things work and not rely on mortal perception? Perhaps
> I benefited from not having finished school if I avoided that
> upper level class: Ruts and Perceptions 425 - Recipes for
> Failure.
>
> Transorbs are better or (no worse in some opinions) and work in 100% of
> the cases. Its a "no brainier" for some of us.
>
> How are they "better"? I've never said that they SHOULD
> NOT be used or that they were somehow inferior. The only
> thing I've said and demonstrated was that there is no
> measurable value FOR using them.
>
> The difference between NO suppression (open circuit) and
> the most aggressive suppression (diode) was a spread of
> 10% in arc-time during contact opening. A diode-transorb
> combo would fall somewhere in between. This means that
> the delta for diode-transorb versus diode-only could be
> as little as 1% and maybe as much a 9% . . . that was
> the point of the experiment, to put some bounds on a
> spread. Further, it's the only claim being made from
> analysis of the data.
>
> While they may not appear to make a difference in a 5 amp resistive load
> with a small relay, Transorbs are proven to have a large advantage in
> inductive and larger current loads with larger or different type relays.
>
> Please cite the experiments and the resulting data.
> Keep in mind that off-the-shelf relays of ALL sizes
> are available with nothing, diode-zener and diode
> only coil suppression. If one technique were so
> decidedly favorable over another technique, why
> hasn't the relay and contactor industry all jumped
> onto one bandwagon as your "entire world" citation
> below suggests they should?
>
> But so what! Bob has his "repeatable" test of one and is convinced he is
> right.
>
> I gathered data on one relay and tested three others of various
> sizes from 2 to 30 or so amps. The measured results with respect
> to effects on contact spreading velocity were similar. If the test
> was poorly crafted then it should be no big deal to demonstrate
> my error.
>
> One size (test) does not fit all cases and perhaps its 90% (for diodes)
> for the average aircraft but clearly not 99.99% based on MY own lab
> repeatable tests.
>
> Please share the data of your tests. What size relay would
> you like to see data on? I have some real honkers. I think I
> could do a 400A interrupt experiment for you. Let us compare
> notes.
>
> The entire world, North America, and Europe for example, ALL say the same
> thing that Eric referenced about Diodes vs. Transorbs etc. Just who is out
> of step here????
>
> Please cite the literature. You've cited applications literature
> on Transorbs before that was shown to be overstated or when it
> came to over-voltage and load-dump mitigation. You once advocated
> a generous sprinkling of Transorbs on the bus . . . one for every
> breaker as I recall. The Transorb is a high power, low energy
> device well suited for mitigating short duration events . . .
> lightning strikes and ESD. I'm well aware of their usefulness. I
> stuck an array of Transorbs on an electro-whizzy just this weekend
> so that I could pass and ESD test in the lab tomorrow morning.
>
> At the same time, others here on the list have shown that the
> Transorb is not suited to a load-dump mitigation without
> deliberate impedance limiting of the energy source (just
> like the manual says). In this discussion, we're definitely in
> the short duration, low energy realm where a Transorb thrives.
>
> But I'll say again, I'm not campaigning against Transorbs for
> this application. I'm only stating that there's no compelling
> evidence support superior performance over the lowly diode for
> coil suppression when it comes to fending off the contact-eating
> gremlins.
>
> There are hundreds in every modern auto. Given the number of autos made
> each year and yes Transorbs do cost more than simple diodes why would auto
> makers spend millions of $$ every year for them if the diode was as good
> and they could save all that money with diodes. Perhaps they know
> something not stated on this list??
>
> Perhaps you have special knowledge of the reasoning behind their
> use? Yes, we use hundreds of them on airplanes too, but they're
> not used on large contactors in lieu of diodes . . . for the
> reasons I've cited.
>
> If you look at the available data including the many references and read
> and understand the available info, its far more compelling than appears on
> the surface.
>
> Let us not talk about "surface" or "appearances". How about
> physics of test setups and numbers derived therefrom.
>
> Is "good enough" OK if you can get better for little more?
>
> I am unwilling to have another useless debate. It ends up with a lot of
> words/heat etc. and no opinion ever gets changed.
>
> It is not my wish to convince you or anyone else of anything
> sir. It's my intent to explain things and support my explanations
> with demonstrable fact and logical conclusions based on those
> facts. If I am in error, nobody would be happier to know the
> nature of the error than I. Go to the lab sir. Show us the
> data you've collected. I need to know how I screwed up. You
> name the test conditions and I'll repeat the test so we can
> compare results. This is where the debate becomes useful . . .
> not to you or I but to those who choose to read it and
> deduce facts of the matter for themselves.
>
> Bob . . .
>
> ---------------------------------------------------------
> < What is so wonderful about scientific truth...is that >
> < the authority which determines whether there can be >
> < debate or not does not reside in some fraternity of >
> < scientists; nor is it divine. The authority rests >
> < with experiment. >
> < --Lawrence M. Krauss >
> ---------------------------------------------------------
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>
> > Coil Suppression:
> >
> > In what aspect does the common, sub-$1, available-everywhere diode fall
> > short enough to justify paying $30 for your single-source solution?
> > --
> > ,|"|"|, Ernest Christley
>
>
>Ernest,
>
>See both of the links I posted,
>
>ref: http://relays.tycoelectronics.com/kilovac/appnotes/transients.asp
Okay, lets take a look at this citation . . .
----------------------------------------------
* Improving Relay Operate Time
Coil suppression can have a profound effect on opening time
which is usually called "release time". The citation speaks
of "operate time" which is usually the time it takes for a
relay to close - which is NOT affected by the popular coil
suppression techniques.
* Calculating Pull-in & Drop-out Voltages at High or Low Temperatures
* Radiation Exposure at High Voltage; Is it a Problem?
* Power Conservation Schemes
* High Voltage Processing of Vacuum Relays
These points are not germane to the discussion at hand and will
be ignored for the moment.
"When a 28 Vdc relay coil is turned off, the inductive energy stored in it
can create surge voltages to 1500 volts on a DC power line. With the
increased use of solid state devices which are sensitive to spikes, relay
coils must be suppressed to limit voltage spikes to a maximum of 50 to 80
volts."
The first paragraph uses impressive numbers . . . 1500 volts will scare
the pants off most neophytes. Of course, it's easy to sign up to the
notion
that solid state devices should be "protected" from such horrific
stresses.
The paragraph ends with an assertion that bringing the offending
spike down
to the 50-80 volt range is the magic bullet. But there's a glaring
error . . .
that 1500 volt spike DOES NOT propagate out onto the bus but instead is
impressed across the mechanism of the controlling device be it switch
or transistor.
"The measure of successful coil suppression depends on the degree to which
the method affects the operation of the relay. Improper or excessive
suppression can cause the relay to suffer from a long release time, slow
contact transfer, and contact bounce on break. All of these conditions will
increase contact arcing when load switching, which will reduce relay life
dramatically."
Yes, slowed transfer and bounce are potentially hard on a relay.
Delayed release is not hard on relays but may have an effect on
system performance in time-critical situations . . . and were
talking MILLISECOND criticality. The paragraph correctly infers that
arcing is the proximate cause of reduced relay life.
"There are a number of common ways for a relay user to suppress relay coil
transients and each has advantages and disadvantages. However, the most
widely used methods utilize zener-diode and/or zener-zener combinations.
These combinations are compact, provide excellent suppression, and do not
affect relay release-time or contact life."
We've already demonstrated that the favorably rated zener-zener
technique has SOME effect on release time. It's less effect than
diode only but the effect is not zero. What is inferred and not
supported is that diode only has a profound effect on relay life . . .
an assertion I don't understand based on experiments I've conducted
over the years. I've not yet been able to confirm the assertion
on any size relay I've worked with to date. If someone cares to
show me an experiment that supports the assertion, I'd be pleased
to know of it.
In the mean time, I'm inclined to treat the words of the
cited posting with skepticism. They take a couple of true
statements, a false statement and then infer some golden
actions to be taken based on those statements. As I stated
in an earlier post, there's a LOT of writing like that
in the wild . . .
In this case, the errors are not harmful. There's nothing
inherently wrong with the proposed "gold standard" but
the writing does not foster understanding. Instead, lots
of myths are launched and preached as gospel because they
came from the Tyco-Amp or P&B bibles.
Bob . . .
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: MOV's/ opening arc |
I disagree that opening time is not significant as related to an aircraft
application.
I have done dozens of repeatable tests where the contact opening rate was
the subject and have demonstrated the duration of the contact opening arc is
extended and the arc intensity is much greater, specifically if you are
looking at a big Contactor opening an inductor or generator like an
alternator. This when the common diode is used across the coil.
The issue of "opening time" is very important as the contact suppressor
Transorb must absorb the energy from the alternator load dump over 50 ms vs.
10 ms (typical) and this means the transorb must be 5X bigger in heat
rating. (The need for a contact suppressor is below a ways)
The specific test set up is the contactor has either the diode or the
bi-directional transorb across the coil and there is a uni-directional
transorb clamping the alternator load dump on the alternator side of the
contacts. The alternator is either properly running or has been failed to
produce full output with no voltage control.
Perhaps not clearly stated above, but the testing was done several years ago
to simulate internal regulator alternators where the "B" lead was opened to
protect the system (Or the pilot simply opened the "B" lead on a healthy
alternator for what ever reason including the false triggering of a OV crow
bar circuit. From the point of the opening of the relay coil to the end of
the time the relay contacts are fully open the Transorb clipping the OV was
tasked with clamping the voltage.
The point is that with out the transorb to clamp the alternator output, the
opening arc voltage jumped to over 100V and the open contacts continued to
arc after they were fully open (this happens regardless of any OV crowbar
present as the crow bar is on the other side of the open contacts). The
Transorb on the alternator side clips the arc voltage during the opening
process and only after the contacts were fully open and unable to restart an
arc did the transorb fail short and then open. Thus the time from relay coil
power off to final contact open determines the power rating of the transorb
and using a diode across the coil added 40+ ms to the total time which is
typically 5 times longer that the transorb must keep the alternator voltage
in line if the transorb was across the coil. Further the duration and
intensity of the arc was increased significantly. If the transorb was not
rated high enough it failed during the process and the arc continued after
the contacts were fully open. For example 50 amps for 50 ms is a lot of
power for the common transorb and they fail short and then quickly fail
open.
Its well known that relays that are required to break DC voltages above the
40-50V range must use a arc quencher circuit or they usually will simply
never stop arcing. Thus something is required to keep the arc voltage under
say 35V until the contacts are well open where the contact gap is big enough
to prevent a restart of the arc.
My conclusion to the above tests is opening a failed internally regulated
alternator where the failure was unregulated high voltage output is not as
simple as some would believe and the "B" lead contactor (if not special
design) has the potential to continue to arc after any type of OV protection
has opened the contactor.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Tuesday, August 22, 2006 8:23 PM
Subject: Re: AeroElectric-List: Re: MOV's
>
>
>
>>
>>True for a bi-directional transorb. But just to muddy the waters, I kind
>>of like the more common uni-directional transorbs. They will still help
>>with positive spikes (if you believe in positive spikes ;) ). Used across
>>a contactor coil, they may delay the opening a smidge compared to a
>>bidirectional transorb, but I suspect that, like the common diode, they
>>are more effective at preventing negative spikes (if you believe in
>>negative spikes comining off contactor coils ;) ). It seems to me that
>>an 18 volt bidirectional transorb may still let negative spikes through
>>that are large enough to damage electrolytic capacitors and perhaps solid
>>state devices, if there is no battery in the circuit. I guess I used
>>diodes on all the contactors and then added a few transorbs on the b-lead
>>just because I could...
>>
>>Are automobiles incorporating transorbs within some devices now? I've
>>never come across one yet that I've noticed.
>>
>>Ken
>>
>>>4. A transorb can be wired up either direction, while a diode must be
>>>wired with the correct polarity.
>>>"
>
> A contactor coil can generate spikes of either polarity. It
> depends on how you switch it. Here's a trace I took off the coil
> of a Cole-Hersee battery contactor with no coil suppression.
> I dug through the archives and found some more data on devices
> common to the OBAM aviation electrical systems. See:
>
> http://www.aeroelectric.com/Pictures/Curves/CH_Bus_Noise_w_0p1_Cap.gif
>
> Here you see a 300+ volt POSITIVE spike because the controlling switch
> (battery master) is in the ground lead. Note that with as little as
> 0.1 uF capacitor on the supply plus whatever the bench supply
> (3A regulated) impedance was, the spike noise coupled to the bus
> was on the order of one or two volts high. And this may have been
> a test setup artifact (meaning smaller than observed). The point of
> this setup was to show that coil spikes are a danger only to the
> controlling device (in this case, battery master switch) and NOT
> to other devices on the bus. These spikes DO NOT propagate about
> the system on the lookout for vulnerable electro-whizzies.
>
> The next trace . . .
>
> http://www.aeroelectric.com/Pictures/Curves/CH_w_120_Ohm.gif
>
> shows the coil suppression benefits of a simple resistor. In this
> case, 120 ohms. The spike is notably smaller, only 90 volts
> or so and again, the spike coupled to the bus was tiny by
> comparison and probably not "real". Note the 22 mS release
> time for the contactor. The next trace . . .
>
> http://www.aeroelectric.com/Pictures/Curves/CH_w_1n5400.gif
>
> shows what happens with the plain diode spike suppressor.
> Note the very slight upward inflection of trace #2 above
> bus voltage where the coil energy is staining against the
> diode's forward voltage drop as positive going spike is
> clamped off. Note the 75 mS release time. The next trace . . .
>
> http://www.aeroelectric.com/Pictures/Curves/CH_w_2x18v_Transorbs.gif
>
> shows the results of a pair of 18v Transorbs (or zeners)
> hooked back to back to emulate the bi-directional device.
> Here the spike clamps off at an expected level of about 18 volts
> above bus voltage and we see a release time of about 14 mS.
> The next trace . . .
>
> http://www.aeroelectric.com/Pictures/Curves/Cole-Hersee_without_Diode.gif
>
>
> Shows a Cole-Hersee contactor release time ploted at some
> other time without a diode but this time, I captured the
> release time of 11 mS. The next trace . . .
>
> http://www.aeroelectric.com/Pictures/Curves/Cole-Hersee_with_Diode.gif
>
>
> is for the same relay and shows a 53 mS release time, again
> about 5x the no-diode time noted above. This data is proprotionally
> consistant with numbers I posted for the smaller relay
> earlier. Note also that one experiment with the CH contactor
> and diode yielded a 75 mS release time while the second
> was only 53 mS. This variability is to be expected and is
> driven by many factors including contactor temperature and
> manufacturing variables. The effects of any one suppression
> technique can be accurately compared only when all techniques
> are used on the same contactor and done with some effort to
> keep the contactor temperature constant for each experiment.
>
> Note that NONE of these traces went to the issue of contact
> spreading velocity and resulting arc durations . . . only changes
> in release time for the various techniques with a peripheral look
> at spike propagation to the bus.
>
> This series of traces serves to illustrate only the variability
> of release time which a number of articles have mistakenly
> assumed that proportionate decreases in contact spreading
> velocity automatically follow. I'll suggest that the
> assumed proportionality does not exist and that their is no
> demonstrable advantage for using one suppression technique over
> another in terms of performance. That suggests we're free to
> choose techniques based on price. The plain vanilla diode is
> hard to beat for price and wide spread availability. However,
> I'd be delighted to be shown wrong if my suggestion is in error.
>
> Bob . . .
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>I cannot let this get past as your statement is in fact TOTALLY
>technically incorrect (vs opinions).
>
>Below requests for links must exclude your own as they need to be unbiased!
>
>----- Original Message ----- From: "Robert L. Nuckolls, III"
>
>To:
>Sent: Tuesday, August 22, 2006 7:32 PM
>Subject: Re: AeroElectric-List: Re: MOV's
>
>
>> In fact, you cannot use a uni-directional Transorb (or
>> plain-vanilla zener) unless combined with a diode to
>> prevent forward conduction as shown in multitudes of catalogs
>> and literature on relays.
>
>Please tell the LIST (specific link please) where a 50V uni-directional
>Transorb device (properly connected) is different from a 50v diode in coil
>supression or forward conduction for that matter.
Okay, here's one.
http://www.azettler.com/pdfs/technical_notes.pdf
Check out the options on page 6. I see no instances
of a single zener/transorb being suggested. How about . .
http://relays.tycoelectronics.com/kilovac/appnotes/fig48.asp
Again, where do we see the use of a single zener/transorb
junction being suggested?
>Of course if you use a Transorb alone as a diode its no better than a
>diode so that configuration is not addressed.
Agreed . . . but then it's not performing the zener style function
that is being sought. You can certainly use the zener/transorb
in this manner but why would you do that? I thought the plain-vanilla
diode is now relegated to fifth rate performance in comparison
to the latest and greatest answer to the airplane owners fondest
dream: "Make my relays last forever". Of what value is it to have
a single zener-transorb installed for the same purpose.
Okay. Let's look at the drawing I posted at:
http://www.aeroelectric.com/temp/Relay_Coil_Suppression.pdf
In cases 1 and 2 we see an illustration of the phenomenon we're trying to
control . . . tame the killer spike.
In cases 3 and 4 we see the effects of the plain vanilla diode and
it's ability to limit the coil collapse spike to under 1 volt.
>Both forward conduct and both block at voltages under 50V. Heck the common
>50V Zener is the same in that respect.
In case 5 I show the only way a single transorb or zener can
be employed in coil suppression. It's cathode must face the + side of
the relay coil and, of course, the breakdown voltage of the device
must exceed supply voltage. In the energized state, the zener is
reverse biased at some point below breakdown voltage.
In case 6, the coil's field collapse applies forward bias
to the zener and it conducts just as an ordinary diode would
as illustrated in case 4 above. I'll confess that my statement was
in error to the effect that one MAY use a single zener/transorb
but it's effect is no different than having used a plain vanilla
diode so applying a zener in this manner is senseless in terms of
using the zener's unique characteristics to achieve some design
goal that a diode wont do.
In case 7 and 8 I show the industry wide practice of adding
both diode and zener in series but with the zener now turned over.
In case 7, the diode prevents forward conduction of the zener
during the energized state.
In case 8 the coil's field collapse now forward biases the
diode and reverse biases the zener such that it's now expected
to conduct at some selected voltage to sink the coil's inductive
energy.
>Both also conduct in both directions if the breakdown V is exceeded. I
>thought we agreed the Transorb is like a zener with the special
>charactericts (specifically its designed for HUGE " zener current" for a
>very short time and perhaps 10,000 times faster as the normal Zener which
>is not capable of fast enough response to perform the function of
>transient supression.
Really? Zeners have been used in this application for decades.
The techniques illustrated in cases 7/8 were developed and
in service long before the advent of Transorbs. The relay
coil spike is a rather sedate event compared to ESD and lightning
and the plain zener's switching times have been and are still
adequate to the task.
>Please show me ANY reference that supports your statement (link please)
>that a single transorb is NOT exactly like a diode when used in relay coil
>supression just by its self and PROPERLY connected to work as a diode. Or
>a Zener for that matter.
>
>In a pinch a zener or a uni-directional transorb can act as a diode in non
>critical circuits as long as the Voltage rating is observed.
Absolutely . . . and I can hold my pants up with a dab
of super-glue on my butt. The question remains, why would
one do that on purpose?
>Finally is there (in the industry) any statements that state that a diode
>is BETTER than a Transorb as you suggest??
I didn't say that. I said that there is no compelling reason
to support the notion that diodes alone have a profound effect
on relay service life which is the mantra used to sell the
more expensive transorb. Both techniques are adequate to the
spike suppression task but using service life as a compelling
sales pitch for transorbs is not supported by the physics.
> (Please supply a link) I sure have not seen any and I have looked as
> has Eric and together we have found many to look at here and in Europe.
> EVERY reference we have found stated the diode is not as good as the
> transorb, or (Zener/diode combination). In fact the LEAST preferred part
> on EVERY list is the diode.
Yup, I'll agree with that. Most folks have taken up the
mantra just as many others still believe we never went
to the moon, that global warming is caused by too many SUVs
and that pure democracy is the best way to run a planet.
A preponderance of conforming opinion does not make it
correct nor alter the laws of physics.
> Not that diodes work OK in most applications usually discussed on this list
Oops? Quantify "OK" . . . are you suggesting that the last
few hours of explanation have all been for naught? Are you
suggesting that the simple diode suppression technique is
really okay after all? Gee Paul, I had some glimmer of hope
that I was going to badger you into doing some real science
after all these years and now you've gone all wobbly on me.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>As I have stated in my original post which you (apparently do not want to
>respond to) I will not get into a debate with you ever again (actually on
>ANY subject) and this subject (transorbs) has been debated between us
>starting nearly 10 years ago.
Yup, that conversation has been enshrined in bytes at
http://aeroelectric.com/articles/spike.pdf
>If you truly are interested in the reasons (pros and cons) of the various
>types of coil suppression please consider reviewing the references Eric
>posted as your reference had little info other than to illustrate the
>types of suppression relay delays. Yes (as you have stated) the total
>circuit (not just the coil) drives the suppression method and Transorbs
>always work and diodes only usually work.
I've read those references. And I've explained what
I've found in them that was in error. If you want
to worship at the altars of Tyco-Amp or Potter-Brumfield
based on your blind acceptance of their Word, that's
your choice . . . but expect to be challenged when you
preach philosophies you cannot yourself explain. You
expose yourself as a propagandist and not as a teacher.
>I will not respond to your comments below (however erroneous some may be)
>as there is no point.
If you can't be a teacher then don't get into
the sandbox to throw mud. Your drive-by insinuations
that errors in my posting are unworthy of your
time and effort is consistent with the behavior
you favored 6 years ago. You stood off and threw
rocks at my explanations and NEVER offered a single
alternative supported by your own explanation of
the underlying physics.
You had plenty to complain about but never a
plan consistent with anyone else's design goals but
your own. You want to play? Fine. If not, then
you know the way out. The unsubscribe link is:
http://www.matronics.com/subscribe/
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | B-lead Contactors (was MOV's) |
>
>I disagree that opening time is not significant as related to an aircraft
>application.
I didn't say that opening time (contact spreading velocity) was
insignificant.
Obviously, the slower moving contact keeps an arc established longer.
What I
said was that the benefits of any other coil suppression technique were
not significantly better than the simple diode with respect to arc duration
in the experiments I conducted. I.e, no compelling reason to take all
the diodes
out and put in bi-directional transorbs or transorb-diode networks.
>I have done dozens of repeatable tests where the contact opening rate was
>the subject and have demonstrated the duration of the contact opening arc
>is extended and the arc intensity is much greater, specifically if you are
>looking at a big Contactor opening an inductor or generator like an
>alternator. This when the common diode is used across the coil.
You use "extended" and "intensity" and "greater" which are
non quantified. How much? And how does your experience illuminate
the tasks before our readers on this List?
>The issue of "opening time" is very important as the contact suppressor
>Transorb must absorb the energy from the alternator load dump over 50 ms
>vs. 10 ms (typical) and this means the transorb must be 5X bigger in heat
>rating. (The need for a contact suppressor is below a ways)
Opps! Stuck your foot in it sir. If you install a transorb as
in cases 7/8 then the transorb is isolated from an alternator
load dump by the accompanying diode. If you install per cases
5/6 then yes, alternator load dump is impressed across the
transorb in the zener mode . . . but if this technique is no
better than a simple diode for coil suppression, why do it?
Use a plain vanilla diode and the "problem" goes away.
>The specific test set up is the contactor has either the diode or the
>bi-directional transorb across the coil and there is a uni-directional
>transorb clamping the alternator load dump on the alternator side of the
>contacts. The alternator is either properly running or has been failed to
>produce full output with no voltage control.
Now were far-afield from the original discussion. You've injected
a feature (alternator load dump) that is a whole new consideration
having nothing to do with what I was attempting to explain earlier this
evening.
>Perhaps not clearly stated above, but the testing was done several years
>ago to simulate internal regulator alternators where the "B" lead was
>opened to protect the system (Or the pilot simply opened the "B" lead on a
>healthy alternator for what ever reason including the false triggering of
>a OV crow bar circuit. From the point of the opening of the relay coil to
>the end of the time the relay contacts are fully open the Transorb
>clipping the OV was tasked with clamping the voltage.
Fine. But what does that have to do with spike suppression
on relay coils?
>The point is that with out the transorb to clamp the alternator output,
>the opening arc voltage jumped to over 100V and the open contacts
>continued to arc after they were fully open (this happens regardless of
>any OV crowbar present as the crow bar is on the other side of the open
>contacts). The Transorb on the alternator side clips the arc voltage
>during the opening process and only after the contacts were fully open and
>unable to restart an arc did the transorb fail short and then open. Thus
>the time from relay coil power off to final contact open determines the
>power rating of the transorb and using a diode across the coil added 40+
>ms to the total time which is typically 5 times longer that the transorb
>must keep the alternator voltage in line if the transorb was across the
>coil. Further the duration and intensity of the arc was increased
>significantly. If the transorb was not rated high enough it failed during
>the process and the arc continued after the contacts were fully open. For
>example 50 amps for 50 ms is a lot of power for the common transorb and
>they fail short and then quickly fail open.
Yes, but you're illuminating a separate issue. If the loads
on a relay's contacts are particularly antagonistic such as
during the load dump phenomenon on a b-lead contactor, then one has
two possibilities. Increase ratings of the contactor or limit
the load dump intensity or a combination of both. But this
is a special case that is only slightly related to the original
discussion. Further, the use of Transorbs on the b-lead contactor
in lieu of diodes is not the ultimate solution.
Further, getting the b-lead opened is only part of the task.
How do you propose to bring a runaway alternator to heel . . .
or is the plan to let it self-destruct?
>Its well known that relays that are required to break DC voltages above
>the 40-50V range must use a arc quencher circuit or they usually will
>simply never stop arcing. Thus something is required to keep the arc
>voltage under say 35V until the contacts are well open where the contact
>gap is big enough to prevent a restart of the arc.
>My conclusion to the above tests is opening a failed internally regulated
>alternator where the failure was unregulated high voltage output is not as
>simple as some would believe and the "B" lead contactor (if not special
>design) has the potential to continue to arc after any type of OV
>protection has opened the contactor.
Absolutely . . . and I think there's a rational way
to mitigate this. If current negotiations for an alternator
drive stand work out, I'll be able to get the energy data
you claimed to have but could/would not share some years
ago. And guess what? As soon as I have the results of the
tests, they will be published here and on my website.
You see, I do intend to service my duty as teacher.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring) |
Hi Dave,
>
>
> How about putting the starter switch on the throttle, so you can do an
> in-flight restart without taking your hands off the sticks and throttle.
>
Er, how many times in a flight do you restart your engine ?
The last time I had to was 16 years ago, when the prop stopped in a
vertical manoeuver during an advanced aerobatic contest. And yes,
reaching for the starter switch during the 4 Gs pull out proved an
interesting exercice. No one noticed from the ground.
But what is the point in normal cases ?
One very good location for the starter switch, is near the fuel valve,
with an arrangement such that the switch is covered by the valve handle
when in the closed position. No starting with the fuel valve closed. The
ubiquitous (in France) Robin DR400 have this feature.
PTT
Trims
Auto pilot disengage
That's all I see necessary on the throttle and stick in a civilian
airplane.
Someone mentionned Intercom PTT, what's the use for such a device ?
Best regards,
Gilles
http://contrails.free.fr
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Flap switches/relay wiring) |
On Aug 23, 2006, at 5:22 AM, Bill Denton wrote:
>
>
> Given that this started as a discussion of the hazards of having
> the flap
> control mounted on the stick, wouldn't mounting the speed brake
> control on
> the stick pose a similar hazard?
IMHO, no. Speed brakes can be used at any speed without danger to the
aircraft. Speed brakes don't produce a pitching moment nor do they
change the capability of the structure to carry the load. If you
inadvertently deploy the speed brakes in flight you can just feel
stupid and laugh it off. If you inadvertently deploy the speed brakes
on final you will increase the rate of descent but you could deal
with that by increasing thrust (or retracting them again).
No, I don't see the accidental deployment of speed brakes and the
accidental deployment of flaps in the same category.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Flap switches/relay wiring) |
On Aug 23, 2006, at 5:44 AM, Dave N6030X wrote:
>
>
> How about putting the starter switch on the throttle, so you can do
> an in-flight restart without taking your hands off the sticks and
> throttle.
How often do you expect to do this? How often might you do this by
accident? What happens if you do this by accident? Given how
infrequent its use would be I would think that leaving it on the
panel is not a real problem.
BTW, I would add speed brakes to my list of things that should be on
the throttle (stick-equipped aircraft with the throttle in your left
hand) along with the radio and intercom PTTs.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring) |
>
>
> BTW, I would add speed brakes to my list of things that should be on
> the throttle (stick-equipped aircraft with the throttle in your left
> hand) along with the radio and intercom PTTs.
>
Hi Brian,
Why a PTT for the intercom ?
Thanks,
Regards,
Gilles,
http://contrails.free.fr
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Flap switches/relay wiring) |
On Aug 23, 2006, at 6:04 AM, Gilles Thesee wrote:
> PTT
> Trims
> Auto pilot disengage
>
> That's all I see necessary on the throttle and stick in a civilian
> airplane.'
I would put the PTT on the throttle and I would add the speed brake
too. And you are right on the auto pilot disengage. That is one of
the things I forgot and *must* be on the stick or yoke.
> Someone mentionned Intercom PTT, what's the use for such a device ?
Some aircraft have such a high noise level that a voice-operated
intercom won't work properly. You use a PTT to activated your mic
into the intercom. Helicopters are known for this as are many
military aircraft.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: MOV's/ Lets more on and stop this interchange! |
You missed my point and I am sorry.
I was looking for a statement from industry where the uni-directional
transorb was NOT to be used. That its not mentioned to me says its OK as it
is really a zener or a simple diode if properly connected and the voltage
ratings recognized.
I know of no such statement as while it may be a silly application it will
work just fine.
I was expecting a simple " its a stupid application but you are right" from
you.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Tuesday, August 22, 2006 10:57 PM
Subject: Re: AeroElectric-List: Re: MOV's
>
>
>
>>
>>
>>I cannot let this get past as your statement is in fact TOTALLY
>>technically incorrect (vs opinions).
>>
>>Below requests for links must exclude your own as they need to be
>>unbiased!
>>
>>----- Original Message ----- From: "Robert L. Nuckolls, III"
>>
>>To:
>>Sent: Tuesday, August 22, 2006 7:32 PM
>>Subject: Re: AeroElectric-List: Re: MOV's
>>
>>
>>> In fact, you cannot use a uni-directional Transorb (or
>>> plain-vanilla zener) unless combined with a diode to
>>> prevent forward conduction as shown in multitudes of catalogs
>>> and literature on relays.
>>
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: B-lead Contactors (was MOV's) |
I did change the subject to point out a case where the diode as a coil
suppressor was a bad idea as it extends the opening time 5x approx.
You did state as far as the relay and its drive there was no difference and
usually the delay in opening was OK and I agree. But there are cases where
its not OK and I stated one used in many aircraft.
I did not quantify the exact results of my tests in my post as that is not
important to the main point that a simple "B" lead contactor may fail to
properly work. The intensity of the arc etc is not important, the fact the
arc continues AFTER the contacts are fully open IS.
There is a lot more testing required for any interested person in the design
of a protection circuit for an internally regulated (very rare) failure of
the internal regulator when the failure mode is full power out.
As there are thousands of owners out there flying with internal regulated
alternators I was trying to point out that the solution once suggested on
this list (at one time the simple "B" lead contactor) is not always a
reliable one. I had hoped that by now you had looked into a solution. Given
the large numbers of aircraft so equipped it would, in my opinion have a
high priority. You know simply saying to not use internal regulated
alternators, just based on your word alone is not sufficient when major
manufacturers/suppliers of experimental aircraft parts etc say otherwise.
My point was to be an informer of a problem and yes it does relate to the
Transorb in a way as I know of NO case where a transorb will not be as good
as a diode. I just pointed out where a diode was NOT as good. My conclusion
was you cannot go wrong with a transorb (and you can with a diode) and so
far you do not seem to have case that disputes that conclusion.
Personally I have changed my mind about internally regulated alternators
after my tests of several years ago. I did and do not have what I consider a
good solution to the problem other that the Kilovac contactor which will
cleanly break a runaway alternator safely. I did mention on this list
recently how to convert a ND alternator to external regulation with a simple
mod to the regulator. I offered to post an article on the subject but only a
couple showed interest and that was not enough for me to spend the time on
it.
Sorry I seem to be unable to state my point without your misunderstanding
it.
Paul
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
Bob I love 99% of your posts. You are doing a great job in helping people
understand and wire their aircraft and based on my limited accident
investigation of auto engine powered aircraft.
I would guess you have saved hundreds of lives in the past 10 years.
The stupid things people do that do not know of your information is
astounding.
However what I was asking for is independent backup of your conclusions as
my background and experience as well as all the data I can find support my
opinion not yours.
What is wrong with asking for independent backup. EVERY source (several
beyond what has been mentioned recently) I can find that really evaluates
(and stacks) the different suppression methods put the simple diode at the
bottom and the bi-directional transorb (or its equivalent) at the top. Sure
the different approaches are "application dependent" as which work better
and which are not as good. My point is the transorb always is good (and at
the top of the lost) so why not use it. No need to retrofit and replace
diodes IF you were to go on and discuss the cases where the diode was not as
good.
The only published paper that disagrees with me comes from you. How about an
industry recognized paper that supports your position? Teachers must be able
to backup what they say with independent references or the student can waver
about that and anything else the teacher says. The "prove me wrong" is
interesting but not useful as most students have no ability to try.
I have no interest in trying to prove what the industry says in unison. I
did see the proving data in the EMI lab when I worked in aerospace that
supported the industry and we simply proceeded on. Why not?, there was no
significant mechanical, electrical or cost difference and in some cases
there was a functional improvement. Sure 90% of the time a diode was just
fine but in the other cases it was not.
I can and have been a teacher but you want to be a teacher and yet get upset
when the student says "prove it". Using only your position (which differs
from industry) is not enough for me (and some others unwilling to post)
given the predictable results. A test by you of a single case or a couple of
cases does not make the statement universally true in all cases.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Tuesday, August 22, 2006 11:18 PM
Subject: Re: AeroElectric-List: Re: MOV's
>
>
>
>>
>>
>>As I have stated in my original post which you (apparently do not want to
>>respond to) I will not get into a debate with you ever again (actually on
>>ANY subject) and this subject (transorbs) has been debated between us
>>starting nearly 10 years ago.
>
> Yup, that conversation has been enshrined in bytes at
>
> http://aeroelectric.com/articles/spike.pdf
>
>
>>If you truly are interested in the reasons (pros and cons) of the various
>>types of coil suppression please consider reviewing the references Eric
>>posted as your reference had little info other than to illustrate the
>>types of suppression relay delays. Yes (as you have stated) the total
>>circuit (not just the coil) drives the suppression method and Transorbs
>>always work and diodes only usually work.
>
> I've read those references. And I've explained what
> I've found in them that was in error. If you want
> to worship at the altars of Tyco-Amp or Potter-Brumfield
> based on your blind acceptance of their Word, that's
> your choice . . . but expect to be challenged when you
> preach philosophies you cannot yourself explain. You
> expose yourself as a propagandist and not as a teacher.
>
>>I will not respond to your comments below (however erroneous some may be)
>>as there is no point.
>
> If you can't be a teacher then don't get into
> the sandbox to throw mud. Your drive-by insinuations
> that errors in my posting are unworthy of your
> time and effort is consistent with the behavior
> you favored 6 years ago. You stood off and threw
> rocks at my explanations and NEVER offered a single
> alternative supported by your own explanation of
> the underlying physics.
>
> You had plenty to complain about but never a
> plan consistent with anyone else's design goals but
> your own. You want to play? Fine. If not, then
> you know the way out. The unsubscribe link is:
>
>
> Bob . . .
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: Potentiometers question |
Bob,
I am building a RV10 and am using your wiring diagram, dual Alt dual bus. I
am also installing a blower motor to use as a source to blow heated air on
to the windscreen. I have sourced a blower, via west marine that is 12
volts 6amp and will work I think quite nice. I would like to have a
variable switch/potentiometer to control the unit, to turn it on as well as
control the fan speed. I have been to DIGIKEY and Mouser to find a POT that
would work, the problem is that I don't know what values to use 5K 10K 15K
25K etc&..for this application.
Can you provide any guidance&.Your help is appreciated
You're going to need something heftier than a panel-mounted,
stand-alone potentiometer. Potentiometers are limited to
currents on the order of a few milliamperes. Rheostats (really
BIG potentiometers) are available to handle much larger
currents on the order of amps . . . but they get so hot
and are so large that mounting them on the panel (or anywhere
else in the airplane) is not practical.
You need a variable duty cycle motor controller. A number of
folks here on the List have been modifying a kit offered by
Marlin P Jones at:
http://www.mpja.com/productview.asp?product=4057+MD
This product is advertised as capable of handling 10A
of motor current. As you can see, it's CONTROLLED by
a relatively small potentiometer (milliamps) but the
motor current is carried by a transistor on a heatsink
(amps). I know nothing about this kit and it has some
obvious packaging issues for aircraft. The electronics
board needs to be mounted in some kind of box and the
potentiometer brought out on leads to be mounted on the
panel.
Suggest you join the AeroElectric List and talk with
folks who have used this kit. They can probably offer
a variety of options for utilizing this kit in your
project.
Bob . . .
---------------------------------------------------------
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
---------------------------------------------------------
________________________________________________________________________________
| From: | Hopperdhh(at)aol.com |
| Subject: | Re: MOV's/ Lets more on and stop this interchange! |
In the automotive world, cars (at least General Motors cars) have to
withstand reverse battery in case someone jumpers a dead battery with a good 12
volt
battery backwards for a specified period of time. I don't remember the
time. It may be 1 minute or only 10 seconds, but they don't want that to wipe
out anything on the car. Maybe this applies to unidirectional Transzorbs, I'm
not sure. Just a thought.
Dan Hopper
Retired Automotive Engineer -- Delphi Delco Electronics (was GM)
RV-7A
In a message dated 8/23/2006 10:16:04 A.M. Eastern Daylight Time,
paulm(at)olypen.com writes:
--> AeroElectric-List message posted by: "Paul Messinger"
You missed my point and I am sorry.
I was looking for a statement from industry where the uni-directional
transorb was NOT to be used. That its not mentioned to me says its OK as it
is really a zener or a simple diode if properly connected and the voltage
ratings recognized.
I know of no such statement as while it may be a silly application it will
work just fine.
I was expecting a simple " its a stupid application but you are right" from
you.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Tuesday, August 22, 2006 10:57 PM
Subject: Re: AeroElectric-List: Re: MOV's
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>
>
>
>>
>>
>>I cannot let this get past as your statement is in fact TOTALLY
>>technically incorrect (vs opinions).
>>
>>Below requests for links must exclude your own as they need to be
>>unbiased!
>>
>>----- Original Message ----- From: "Robert L. Nuckolls, III"
>>
>>To:
>>Sent: Tuesday, August 22, 2006 7:32 PM
>>Subject: Re: AeroElectric-List: Re: MOV's
>>
>>
>>> In fact, you cannot use a uni-directional Transorb (or
>>> plain-vanilla zener) unless combined with a diode to
>>> prevent forward conduction as shown in multitudes of catalogs
>>> and literature on relays.
>>
________________________________________________________________________________
| From: | "glen matejcek" <aerobubba(at)earthlink.net> |
Expanding a bit on where this thread has gone, let me toss out some
thoughts on cockpit ergonomics and safety. I'm building an RV-8, which of
course has a narrow panel. Economy of acreage is important. Also, a
fundamental of crashworthiness is to not put switches where you will be
impaled by them. Hence, I don't have any switches on my main panel.
My basic concept for switch location is to put the highest usage switches
on the stick, with the next highest usage rate and 'use 'em quick' safety
related switches on the left (throttle hand) side, leaving the right side
(stick hand) for the rarely used stuff.
The application of this philosophy to my particular equipment list leads to
the following:
My RAC / MAC stick grip has PTT, 2 axis trim, A/P disconnect, and EFIS
engine page call up / dismiss. Nothing on the throttle. The lower edge of
the throttle quadrant ass'y is home to the cockpit light dimmers. Just
above / fwd of the throttle on the left sub panel and within very easy
reach of my throttle hand are my 'oh crap' switches. They include fuel
pump, A/P arm / off, rear seat stick switch disable / trim sys disable, and
flaps. The next row up has the music auto mute function, ARC, and OVM
reset switches. Just above are the clock and the flap position indicator.
The left side of the main panel holds xpder, coms, back up EFIS, and nav.
Central and right is the main EFIS display. The right side of the panel
holds the audio panel. The right sub panel has the trim indicators, remote
ELT head, battery switches, ignition switches, EFIS 2 switch, and start
switch. The right console has the exterior lights, pitot heat, Hobbs
meter, and power distribution CBs.
So far, I'm very happy with this layout. Of course, it' the 12th iteration
of the design. I would encourage folks to take their time and prioritize
and group switches according to some consistent and user friendly scheme.
'Chair flying' complete flight profiles, imagining / simulating the whole
process from power up through engine start, T/o, ldg, and securing will
help a lot. Besides, then you'll have a good excuse when the spouse
catches you sitting there making airplane noises...
glen matejcek
aerobubba(at)earthlink.net
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
Yes I remember that interchange and its a wonderful example how selective
cut and paste can change what I was saying and its context.
Its a masterpiece.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Tuesday, August 22, 2006 11:18 PM
Subject: Re: AeroElectric-List: Re: MOV's
> Yup, that conversation has been enshrined in bytes at
>
> http://aeroelectric.com/articles/spike.pdf
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>Bob I love 99% of your posts. You are doing a great job in helping people
>understand and wire their aircraft and based on my limited accident
>investigation of auto engine powered aircraft.
>
>I would guess you have saved hundreds of lives in the past 10 years.
>
>The stupid things people do that do not know of your information is
>astounding.
Thank you for the kind words . . .
>However what I was asking for is independent backup of your conclusions as
>my background and experience as well as all the data I can find support my
>opinion not yours.
I'm only asking for independent review (yours) of what I've
offered based on your perceptions of the physics and NOT
upon a dump from industry's promotional literature.
>What is wrong with asking for independent backup. EVERY source (several
>beyond what has been mentioned recently) I can find that really evaluates
>(and stacks) the different suppression methods put the simple diode at the
>bottom and the bi-directional transorb (or its equivalent) at the top.
>Sure the different approaches are "application dependent" as which work
>better and which are not as good. My point is the transorb always is good
>(and at the top of the lost) so why not use it. No need to retrofit and
>replace diodes IF you were to go on and discuss the cases where the diode
>was not as good.
>
>The only published paper that disagrees with me comes from you. How about
>an industry recognized paper that supports your position? Teachers must be
>able to backup what they say with independent references or the student
>can waver about that and anything else the teacher says. The "prove me
>wrong" is interesting but not useful as most students have no ability to try.
I am NOT disagreeing with you in that the zener-diode technique certainly
works 100% of the time. The entire thrust of my posting was to dispel any
notions that folks who choose to use the lowly diode are at-risk for reduced
relay and contactor life. It's just that simple sir. I'm mystified as to
why you get wrapped around the good-better-best axle when those terms
are non-quantified and not even offered in the context of exactly HOW one
technique excels.
You're fond of citing lots of literature while I prefer to make measurements
and explore for myself the value/hazards of any technique being discussed.
I've offered my experimental results for the purpose of soliciting
considered critical review to either support or refute a hypothesis.
I chose this technique because literature without supporting experimental
data proves nothing while the repeatable experiment offered for
critical review illuminates the path for success.
>I have no interest in trying to prove what the industry says in unison. I
>did see the proving data in the EMI lab when I worked in aerospace that
>supported the industry and we simply proceeded on. Why not?, there was no
>significant mechanical, electrical or cost difference and in some cases
>there was a functional improvement. Sure 90% of the time a diode was just
>fine but in the other cases it was not.
. . . agreed . . . and I'm only suggesting that the 10% of cases
were the simple diode is found lacking do not occur in the OBAM
aircraft.
>I can and have been a teacher but you want to be a teacher and yet get
>upset when the student says "prove it".
Nobody, repeat NOBODY upsets me over a discussion of
facts and physics. Your the only person on this list who
has succeeded in upsetting me when you alluded to a cadre
of unhappy customers of my products who according to you
were so intimidated by my aura that they would not return
their purchases for a full refund.
I could only assume that you had chosen to insert yourself
into what was intended to be an honorable supplier/consumer
relationship. That DID upset me.
I will confess to some frustration when data and test
techniques offered to support a hypothesis produces a
literature storm of information not specific to discussion
of the hypothesis.
> Using only your position (which differs from industry) is not enough for
> me (and some others unwilling to post)
> given the predictable results. A test by you of a single case or a
> couple of cases does
> not make the statement universally true in all cases.
My position differs not a whit from industry when it comes to
making measurements and deducing performance or lack thereof
based on those measurements. But like laundry soap, cars, and
mouthwash, the promotional literature (including much of the
applications notes) are not written with good science and understanding
as goals. For example: I'm about ready to publish a detailed review of
the data sheet for the MC33092 internal regulator where
I will show that in spite of the product's modern integrated
circuit manufacturing with a whole fist full of transistors,
the manner in which it is used in alternators prevents
exploitation of its special features. In practice, it
performs no better than the two-transistor regulators we
were installing on Cessnas 40 years ago.
By your logic I could consider assembling a house with
titanium nails and be 100% assured of future performance.
When the astute system designer compares REQUIREMENTS with
techniques and materials capable of meeting requirements,
the competitive and successful product may very well NOT use
titanium nails.
Words here on the list have recommended that builders rip out
all their diodes and replace them with a more expensive product
and promoted by the notion that doing so has cost-of-ownership
value for having made the switch.
I am only suggesting that the notion is pure marketing hype
and not supported by any experiments I've conducted to explore
the potential benefits. I was not arguing any good-better-best,
only against the notion that the product being offered produces
a demonstrable return on investment. In this case a plain ol'
cement coated box nail does the job. If someone chooses to use
the titanium nail cause he has the time and doesn't mind the
expense, fine. But I object to marketing the titanium nail with
the use of unsupported assertions designed to instill worries
on the part of the potential neophyte customer.
There's that honorable consumer/supplier relationship thing
again.
Bob . . .
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: MOV's/ Lets more on and stop this interchange! |
I agree with your title of your post.
As for your comment about reverse voltage it would apply to diodes also.
Paul
----- Original Message -----
From: Hopperdhh(at)aol.com
To: aeroelectric-list(at)matronics.com
Sent: Wednesday, August 23, 2006 7:33 AM
Subject: Re: AeroElectric-List: Re: MOV's/ Lets more on and stop this
interchange!
In the automotive world, cars (at least General Motors cars) have to
withstand reverse battery in case someone jumpers a dead battery with a good
12 volt battery backwards for a specified period of time. I don't remember
the time. It may be 1 minute or only 10 seconds, but they don't want that
to wipe out anything on the car. Maybe this applies to unidirectional
Transzorbs, I'm not sure. Just a thought.
Dan Hopper
Retired Automotive Engineer -- Delphi Delco Electronics (was GM)
RV-7A
In a message dated 8/23/2006 10:16:04 A.M. Eastern Daylight Time,
paulm(at)olypen.com writes:
You missed my point and I am sorry.
I was looking for a statement from industry where the uni-directional
transorb was NOT to be used. That its not mentioned to me says its OK as
it
is really a zener or a simple diode if properly connected and the
voltage
ratings recognized.
I know of no such statement as while it may be a silly application it
will
work just fine.
I was expecting a simple " its a stupid application but you are right"
from
you.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
To:
Sent: Tuesday, August 22, 2006 10:57 PM
Subject: Re: AeroElectric-List: Re: MOV's
>
>
>
>>
>>
>>I cannot let this get past as your statement is in fact TOTALLY
>>technically incorrect (vs opinions).
>>
>>Below requests for links must exclude your own as they need to be
>>unbiased!
>>
>>----- Original Message ----- From: "Robert L. Nuckolls, III"
>>
>>To:
>>Sent: Tuesday, August 22, 2006 7:32 PM
>>Subject: Re: AeroElectric-List: Re: MOV's
>>
>>
>>> In fact, you cannot use a uni-directional Transorb (or
>>> plain-vanilla zener) unless combined with a diode to
>>> prevent forward conduction as shown in multitudes of catalogs
>>> and literature on nbsp; = Use lities Day --> - NEW
MATRONICS WEB FORUMS -
bsp; --> nbsp; - NEW MATRONICS LIST WIKI -
========================
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring) |
Brian,
>
>> Someone mentionned Intercom PTT, what's the use for such a device ?
>
> Some aircraft have such a high noise level that a voice-operated
> intercom won't work properly. You use a PTT to activated your mic into
> the intercom. Helicopters are known for this as are many military
> aircraft.
Understand.
Thank you for responding.
Best regards,
Gilles,
http://contrails.free.fr
________________________________________________________________________________
| From: | "Doug Windhorn" <N1DeltaWhiskey(at)comcast.net> |
| Subject: | Re: RE: Pullable 80A Circuit Breaker |
Matt,
I am not an expert either, but I*R is not the only source of heat that might
affect a CB. For thermally activated (TA) CB, it is quite possible for
external heat sources to reduce the load carrying capacity of the TACB by
providing "pre-heating."
Say a TACB will trip when the sensing element reaches 600F (I have no idea
what the actual temperature is - it may be much less than that). At ambient
temperature of 70F, we have to provide enough heating to elevate the sensor
temperature by 530F. However, if a situation arises which causes the
ambient temp of the unit to rise, say to 300F, the amount of current the
TACB to elevate the temp of the sensor an additional 300F is decreased
(i.e., reduced capacity).
I visited a client just this week where they were having nuisance trips of a
circuit breaker. Cause: determined to be a bad connection of the CB to the
bus. Remedy: the bus was flipped over to get the pitting away from the CB
contacts and a secure connection was then made.
Regards,
Doug Windhorn
----- Original Message -----
From: "Matt Prather" <mprather(at)spro.net>
Sent: Tuesday, 22 August, 2006 9:15
Subject: Re: AeroElectric-List: RE: Pullable 80A Circuit Breaker
>
>
> Err.. I am not an expert, but I don't think that is completely correct.
>
> Heat generated is correct, but the heat is generated solely by the current
> passing through the CB. The system voltage has no bearing on how much
> heat is generated. Draw the circuit and you can see why. The CB goes in
> series with the load. Beit a 2V or 200V system, a particular current
> through the CB causes a corresponding voltage drop across the CB while the
> CB is closed.
>
> The voltage rating is more related to the ability of the CB to open an
> operating (overloaded) circuit. The higher the system voltage the harder
> it is to open the circuit (break the current) for a given current.
> Voltage rating is likely about contact speed and distance (maybe not
> both). A larger system voltage implies the need for faster contacts
> and/or larger contact distance.
>
>
> Regards,
>
> Matt-
>
>>
>>
>> While I am waiting for the real experts to weigh in, I offer the
>> following unsubstantiated feeling:
>>
>> I don't think a cb "senses" either volts or amps. Rather it reacts
>> to heat, whose generation is better measured in watts which is a
>> function of both.
>>
>> I would therefore surmise that the cb in question would be well
>> within its rated range; however would probably not trip a 14 volt
>> load until 160 amps.
>>
>> well, where are the electro-experts now that we need them??
>> Denis Walsh
>>
>> On Aug 22, 2006, at 07:06 292080008, glen matejcek wrote:
>>
>>>
>>>
>>>
>>> Hi Stan-
>>>
>>>> I bought one at Sun n Fun only to discover later that it is 28v.
>>>
>>> 28V is the maximum system voltage for that CB. The CB you bought
>>> should be
>>> fine for your 14V installation.
>>>
>>> glen matejcek
>>> aerobubba(at)earthlink.net
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>>
>
>
>
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
I have long ago given up trying to challenge every industry position. I do
not have the time or interest to do so. When I do run across something in a
design that is not consistent with the industry I do, and have investigated
just what is different.
The industry papers of the time were from relay manufacturers who had no
reason to support one suppressor method or the other as they did not sell
suppressors of any type (at the time) Their interest appeared to be to show
how to get the most reliable use of their products which ranged from very
small relays to huge ones and thus the recommendations were designed to be
general and not always apply to any specific case.
In the case of transorbs; many years ago I noted that a designer had used a
diode and there were unwanted noise introduced into the system. It was
determined that the opening delay and more important showed start to finish
contact opening time was part of the problem. At that time I want into the
EMI lab and with expert help we determined that part of the required fix was
to quicken the opening contact time (not the delayed start of opening but
the duration of contact opening).
PART of the solution was replacing the Diode with a Transorb. There was more
required that evolved contact arc suppression.
The general conclusion was an across the board replacement of diodes with
transorbs as it did not hurt and in rare cases prevent problems. No retrofit
was made just new design used transorbs.
I agree that your documented test of a small relay showed no significant
time of contact opening but that is not necessarily so with power contactors
seen in aircraft.
Now in the case of experimental aircraft I have discovered one case the "B"
lead contactor can require a transorb as a partial solution to contact
arcing and continued arcing in one failure mode of the alternator.
I only intended to point out that case not make a big deal of it. BTW I am
not the only you have gotten up set with but perhaps the most memorable.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Wednesday, August 23, 2006 8:16 AM
Subject: Re: AeroElectric-List: Re: MOV's
>
>
>
>>
>>
>>Bob I love 99% of your posts. You are doing a great job in helping people
>>understand and wire their aircraft and based on my limited accident
>>investigation of auto engine powered aircraft.
>>
>>I would guess you have saved hundreds of lives in the past 10 years.
>>
>>The stupid things people do that do not know of your information is
>>astounding.
>
> Thank you for the kind words . . .
>
>
>>However what I was asking for is independent backup of your conclusions as
>>my background and experience as well as all the data I can find support my
>>opinion not yours.
>
> I'm only asking for independent review (yours) of what I've
> offered based on your perceptions of the physics and NOT
> upon a dump from industry's promotional literature.
>
>
________________________________________________________________________________
| From: | "Bob C. " <flyboy.bob(at)gmail.com> |
Bob,
West Mountain Radio http://www.westmountainradio.com/SuperPWRgate.htm
makes a product call "Super PWRgate" that looks like a reasonable
device to support a two battery (one large - one smaller) environment.
My total load with lights etc. on is about 45-50A . . . critical load
< 20A . . . really critical load < 10A?
Please take a look and give your opinion.
Thanks,
Bob Christensen
RV-8 Bldr - SE Iowa
________________________________________________________________________________
| From: | "Bob C. " <flyboy.bob(at)gmail.com> |
Bob,
West Mountain Radio http://www.westmountainradio.com/SuperPWRgate.htm
makes a product call "Super PWRgate" that looks like a reasonable
device to support a two battery (one large - one smaller) environment.
My total load with lights etc. on is about 45-50A . . . critical load
< 20A . . . really critical load < 10A?
Please take a look and give your opinion.
Thanks,
Bob Christensen
RV-8 Bldr - SE Iowa
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Contactbounce PIX |
I have attached up some scope pictures of contact bounce as well as one of a
main bus transient from the removal of a load by turning off a resistive 10
amp load.
In all cases the horizontal speed is 1 ms per small square and 2 ms per
large square. The vertical resolution is 5V per large square. Only small
squares are clear in the transient jpg.
All PIX have been greatly reduced in resolution for fast downloading.
The contact bounce pix were from the contactor sold by Wicks at the time for
cont duty and I added the diode across the coil. There was only enough
voltage and current used to show the contact open and close and to eliminate
the normal arcing as much as possible when a significant load was switched.
My first point is I have seen transients that are repeatable but not high
voltage on the bus. High enough to consistently trip Bobs OVP from the
design of several years ago. The load was switched off with a 20 amp rated
auto relay.
The contact bounce on power contactors can be significant but range widely
from one test to the next with the same contactor. The Kilovac has no or at
most one quick contact bounce on open and none on closing.
Here the opening bounce extends over 14MS from start to end.
Replacing the diode with a transorb helped shorten the bounce duration but
did not eliminate all the bounce.
For general interest. There are lots more but I see no point in posting them
as relays vary and some bounce more than others. The "fire" across the
contacts can in some cases be huge whan large currents and or an inductive
load is switched.
Paul
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: Potentiometers question |
sorry I've lost the original post but that is a huge fan for defrost. If
you really think you need it you could also look at an automotive fan
speed control arrangement.
For just blowing air up through the instrument glareshield I found that
a little axial fan as seen in computer power supplies seems to work fine
for me. No speed control required.
Ken
Robert L. Nuckolls, III wrote:
>
>
>
> Bob,
>
> I am building a RV10 and am using your wiring diagram, dual Alt dual
> bus. I am also installing a blower motor to use as a source to blow
> heated air on to the windscreen. I have sourced a blower, via west
> marine that is 12 volts 6amp and will work I think quite nice. I would
> like to have a variable switch/potentiometer to control the unit, to
> turn it on as well as control the fan speed. I have been to DIGIKEY
> and Mouser to find a POT that would work, the problem is that I don't
> know what values to use 5K 10K 15K 25K etc&..for this application.
>
> Can you provide any guidance&.Your help is appreciated
>
>
> You're going to need something heftier than a panel-mounted,
> stand-alone potentiometer. Potentiometers are limited to
> currents on the order of a few milliamperes. Rheostats (really
> BIG potentiometers) are available to handle much larger
> currents on the order of amps . . . but they get so hot
> and are so large that mounting them on the panel (or anywhere
> else in the airplane) is not practical.
>
> You need a variable duty cycle motor controller. A number of
> folks here on the List have been modifying a kit offered by
> Marlin P Jones at:
>
> http://www.mpja.com/productview.asp?product=4057+MD
>
> This product is advertised as capable of handling 10A
> of motor current. As you can see, it's CONTROLLED by
> a relatively small potentiometer (milliamps) but the
> motor current is carried by a transistor on a heatsink
> (amps). I know nothing about this kit and it has some
> obvious packaging issues for aircraft. The electronics
> board needs to be mounted in some kind of box and the
> potentiometer brought out on leads to be mounted on the
> panel.
>
> Suggest you join the AeroElectric List and talk with
> folks who have used this kit. They can probably offer
> a variety of options for utilizing this kit in your
> project.
>
> Bob . . .
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring |
| From: | Jon & Kathryn Hults <legacy(at)speedband.com> |
Aircraft Extras in Ohio ( http://www.aircraftextras.com ) has a system that
will disable your flap switch at whatever speed you want...presumably the
top of the white arc. That way, inadvertent activation of your flap switch
in cruise would do nothing. Inadvertent activation below flap speed would
not be prevented, but would cause no harm either.
I too am going to have a flap switch on my stick, but I'm also going to
install Aircraft Extra's accidental flap deployment protection system.
Jon Hults
Legacy
________________________________________________________________________________
| From: | Deems Davis <deemsdavis(at)cox.net> |
| Subject: | "Paddle Type" Flap position switch? |
I've searched in vain for a flap position switch which has a wide broad
flat paddle for the toggle, similar to what Cessna uses. anybody know
where you can pick one of the up?
Deems Davis # 406
Fuse/Finishing/Panel
http://deemsrv10.com/
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: "Paddle Type" Flap position switch? |
On Aug 23, 2006, at 6:40 PM, Deems Davis wrote:
>
>
> I've searched in vain for a flap position switch which has a wide
> broad flat paddle for the toggle, similar to what Cessna uses.
> anybody know where you can pick one of the up?
Make a paddle out of wood and epoxy it to a standard spring-return-to-
center toggle switch.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | "Bruce Gray" <Bruce(at)glasair.org> |
| Subject: | Flap switches/relay wiring) |
My speed brake deployment has been tested to Vne. Accendital deployment only
causes the airplane to slow down.
Bruce
www.glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill
Denton
Sent: Wednesday, August 23, 2006 8:23 AM
Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay wiring)
Given that this started as a discussion of the hazards of having the flap
control mounted on the stick, wouldn't mounting the speed brake control on
the stick pose a similar hazard?
________________________________________________________________________________
| From: | Kevin Horton <khorton01(at)rogers.com> |
| Subject: | Re: Flap switches/relay wiring) |
What happens if there is an accidental deployment during the landing
flare?
Kevin Horton
On 23 Aug 2006, at 09:05, Bruce Gray wrote:
>
>
> My speed brake deployment has been tested to Vne. Accendital
> deployment only
> causes the airplane to slow down.
>
> Bruce
> www.glasair.org
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
> Bill
> Denton
> Sent: Wednesday, August 23, 2006 8:23 AM
> To: aeroelectric-list(at)matronics.com
> Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/
> relay wiring)
>
>
>
>
> Given that this started as a discussion of the hazards of having
> the flap
> control mounted on the stick, wouldn't mounting the speed brake
> control on
> the stick pose a similar hazard?
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: "Paddle Type" Flap position switch? |
>
>I've searched in vain for a flap position switch which has a wide broad
>flat paddle for the toggle, similar to what Cessna uses. anybody know
>where you can pick one of the up?
See:
http://www.aeroelectric.com/Pictures/Switches/FLAPS3.JPG
http://www.aeroelectric.com/Pictures/Switches/FLAPS2.JPG
http://www.aeroelectric.com/Pictures/Switches/FLAPS1.JPG
I could give you a part number for the switch used on
Bonanzas but you'd have to mortgage the dog to afford
it. Best you consider the DIY project.
Bob . . .
---------------------------------------------------------
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
---------------------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: Flap switches/relay wiring |
Beware of "bells and whistles" that add complexity. More than
once I've encountered costly field service issues with
so called "enhancements" to performance that became problem
children for at least some owners. A part that is NOT on your
airplane will never be a failure/performance issue.
Bob . . .
>
>
>Aircraft Extras in Ohio ( http://www.aircraftextras.com ) has a system that
>will disable your flap switch at whatever speed you want...presumably the
>top of the white arc. That way, inadvertent activation of your flap switch
>in cruise would do nothing. Inadvertent activation below flap speed would
>not be prevented, but would cause no harm either.
>
>I too am going to have a flap switch on my stick, but I'm also going to
>install Aircraft Extra's accidental flap deployment protection system.
>
>Jon Hults
>Legacy
>
>
>--
>
>
>-- incoming mail is certified Virus Free.
>Checked by AVG Anti-Virus.
Bob . . .
---------------------------------------------------------
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
---------------------------------------------------------
________________________________________________________________________________
| From: | "Bill Denton" <bdenton(at)bdenton.com> |
| Subject: | Flap switches/relay wiring) |
I was thinking more in terms of the other end of the spectrum...
What would happen if the speed brakes were accidentally deployed on short
final?
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Bruce
Gray
Sent: Wednesday, August 23, 2006 8:06 AM
Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay
wiring)
My speed brake deployment has been tested to Vne. Accendital deployment only
causes the airplane to slow down.
Bruce
www.glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill
Denton
Sent: Wednesday, August 23, 2006 8:23 AM
Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay wiring)
Given that this started as a discussion of the hazards of having the flap
control mounted on the stick, wouldn't mounting the speed brake control on
the stick pose a similar hazard?
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>Bob,
>
>West Mountain Radio http://www.westmountainradio.com/SuperPWRgate.htm
>makes a product call "Super PWRgate" that looks like a reasonable
>device to support a two battery (one large - one smaller) environment.
>
>My total load with lights etc. on is about 45-50A . . . critical load
>< 20A . . . really critical load < 10A?
>
>Please take a look and give your opinion.
The question to be asked/answered is: "How does this
product deliver a return on invesetment either for
cost or performance over the use of simple battery
contactors for each battery wired as suggested in Z-30."
The same question was explored on the topic of
battery isolators some years ago at:
http://aeroelectric.com/articles/bat_iso2.pdf
It's not clear from the West Mountain Radio
instruction manual how this would be usef in
an airplane.
http://www.westmountainradio.com/pdf/PG40Smanual.pdf
It's purpose seems to be for the "more accurate"
charging of one battery and to power some accessory
from either battery or AC mains as the situation
dictates. This is a bit different than the philosophy
offered for the installation and management of dual
batteries.
Be wary of "bells and whistles" that seem to offer
some whizzy features. Make sure they first address
REQUIREMENTS you have established for how your system
needs to operate. Then evaluate return on investment
for the proposed product as compared with alternatives
with an eye on (1) parts count reduction - parts not on
the airplane are not going to break, (2) maintainability -
if it breaks in Podunk TN, how hard will it be to
get it fixed?, (3) weight - a pound of airplane saved
is a pound of payload earned, (4) volume - no airplane
has too much room to put stuff, (5) $time$ to install -
here's your "investment" and (6) operability - does it
increase workload? Does it demand special words in the
POH that your fellow pilots would have to stop and think
about. Finally (7) how does it affect your failure
mode effects analysis. How will you KNOW it's broke?
Are potential failures pre-flight detectable? Is a
plan-B procedure for failure called for in the POH?
This may seem like I'm making a mountain out of a
mole-hill but these are the rudimentary foundations for
systems design decisions on "real" airplanes that have
served us well for nearly a century. I've not been
made privy to an alternative philosophy that has proven
useful. In fact, failure to observe this recipe for
success has cost many of my clients and their customers
bucket-loads of money and $time$ wasted on ill-conceived
systems design decisions.
Your own return-on-investment study will determine
the usefulness of any particular feature under
consideration. Use this List as your critical design
review. It's a win-win. Either you shut off the computer
grinning ear-to-ear and run off to the store to buy some
whippy electro-whizzie or you keep a poorly considered
idea from going into your airplane.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring) |
Bill Denton a crit :
>
> I was thinking more in terms of the other end of the spectrum...
>
> What would happen if the speed brakes were accidentally deployed on short
> final?
>
>
The end result would be "interesting" ;-)
Fighters have speed brakes on the throttle, because they need it for
formation flying, in-flight refuelling, etc. Their jet engines do not
allow for quick speed reduction.
On other types, airliners or gliders, the speed brakes do have a
dedicated and (hopefully) unmistakeable lever.
On a piston single, unless the owner is a nostalgic ex-fighter pilot, is
a throttle switch really desirable ? Piston engines and props allow for
quick speed reduction for formation flying, for instance.
Any time you add a switch on the stick or throttle, provision must be
made to avoid inadvertent actuation.
I know of at least one clever guy who installed the starter switch on
the throttle...
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
| Subject: | Flap switches/relay wiring) |
| From: | "George Braly" <gwbraly(at)gami.com> |
We have installed several dozen sets of speed brakes on aircraft as an
option with the turbo normalizing systems for the Bonanzas.
There have been lots of variations in the locations of the activation
switches.
I have flown all of these different locations - - from the yoke to the
panel.
My thoughts:
Don't put anything on the stick that you will normally use once or twice
during each flight. That is a mistake and generates more problems.
Things that will be used multiple times - - trim, mic button, are the
two most important - - are appropriate.
Regards, George
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill
Denton
Sent: Thursday, August 24, 2006 7:14 AM
Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay
wiring)
I was thinking more in terms of the other end of the spectrum...
What would happen if the speed brakes were accidentally deployed on
short
final?
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Bruce
Gray
Sent: Wednesday, August 23, 2006 8:06 AM
Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay
wiring)
My speed brake deployment has been tested to Vne. Accendital deployment
only
causes the airplane to slow down.
Bruce
www.glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill
Denton
Sent: Wednesday, August 23, 2006 8:23 AM
Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay
wiring)
Given that this started as a discussion of the hazards of having the
flap
control mounted on the stick, wouldn't mounting the speed brake control
on
the stick pose a similar hazard?
________________________________________________________________________________
| Subject: | Flap switches/relay wiring) |
| From: | "Matt Prather" <mprather(at)spro.net> |
Speed brakes are usually very small drag producers that provide energy
control while at high indicated airspeeds. Once slowed to a low airspeed,
speed brakes represent a very small portion of airframe drag. Sometimes,
takeoff performance isn't even particularly degraded with the brakes
extended.
Regards,
Matt-
>
>
> I was thinking more in terms of the other end of the spectrum...
>
> What would happen if the speed brakes were accidentally deployed on short
> final?
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Bruce
> Gray
> Sent: Wednesday, August 23, 2006 8:06 AM
> To: aeroelectric-list(at)matronics.com
> Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay
> wiring)
>
>
> My speed brake deployment has been tested to Vne. Accendital deployment
> only
> causes the airplane to slow down.
>
> Bruce
> www.glasair.org
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill
> Denton
> Sent: Wednesday, August 23, 2006 8:23 AM
> To: aeroelectric-list(at)matronics.com
> Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay
> wiring)
>
>
>
>
> Given that this started as a discussion of the hazards of having the flap
> control mounted on the stick, wouldn't mounting the speed brake control on
> the stick pose a similar hazard?
>
>
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring) |
| From: | "Matt Prather" <mprather(at)spro.net> |
Mr. Thesee,
I just posted another message. Yours reminds me that I didn't mention a
few things...
Early (modern?) fighter jets often flew their final approach with speed
brakes at least partially extended. This allowed them to carry nearly
full power on the engine while on approach. If they had to abort an
approach, the speed brakes could be stowed much more quickly than climb
power could be attained from the jet. The speed brakes were relatively
large, and not designed to be deployed at high airspeeds.
Gliders often have truly enormous speed brakes/spoilers which allow steep
approaches to be flown - drastically reducing their glide ratio. All of
the ones I have seen are mechanically actuated by a large lever in the
cockpit.
The speed brakes that I was thinking of are like the Precise Flight units
commonly installed on higher performance piston singles like Mooney's,
Lancairs, Glassairs, Bonanzas and Cessna 210's. These are electrically
actuated. Mounting the control switch either near/on the throttle or on
the control wheel/stick might make the most sense. These units are
approved for airspeeds up to Vne.
http://preciseflight.com/viewpage.php?pID=10
Regards,
Matt-
> <Gilles.Thesee@ac-grenoble.fr>
>
> Bill Denton a crit :
>>
>>
>> I was thinking more in terms of the other end of the spectrum...
>>
>> What would happen if the speed brakes were accidentally deployed on
>> short
>> final?
>>
>>
>
> The end result would be "interesting" ;-)
>
> Fighters have speed brakes on the throttle, because they need it for
> formation flying, in-flight refuelling, etc. Their jet engines do not
> allow for quick speed reduction.
> On other types, airliners or gliders, the speed brakes do have a
> dedicated and (hopefully) unmistakeable lever.
>
> On a piston single, unless the owner is a nostalgic ex-fighter pilot, is
> a throttle switch really desirable ? Piston engines and props allow for
> quick speed reduction for formation flying, for instance.
> Any time you add a switch on the stick or throttle, provision must be
> made to avoid inadvertent actuation.
>
> I know of at least one clever guy who installed the starter switch on
> the throttle...
>
> Regards,
> Gilles Thesee
> Grenoble, France
> http://contrails.free.fr
>
>
________________________________________________________________________________
| From: | Sam Marlow <sam.marlow(at)adelphia.net> |
| Subject: | Re: "Paddle Type" Flap position switch? |
Gulf Coast Avionics in Florida.
Robert L. Nuckolls, III wrote:
>
>
>
>>
>>
>> I've searched in vain for a flap position switch which has a wide
>> broad flat paddle for the toggle, similar to what Cessna uses.
>> anybody know where you can pick one of the up?
>
>
> See:
>
>
> http://www.aeroelectric.com/Pictures/Switches/FLAPS3.JPG
> http://www.aeroelectric.com/Pictures/Switches/FLAPS2.JPG
> http://www.aeroelectric.com/Pictures/Switches/FLAPS1.JPG
>
> I could give you a part number for the switch used on
> Bonanzas but you'd have to mortgage the dog to afford
> it. Best you consider the DIY project.
>
> Bob . . .
>
>
> ---------------------------------------------------------
> < What is so wonderful about scientific truth...is that >
> < the authority which determines whether there can be >
> < debate or not does not reside in some fraternity of >
> < scientists; nor is it divine. The authority rests >
> < with experiment. >
> < --Lawrence M. Krauss >
> ---------------------------------------------------------
>
>
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring) |
Matt and all,
> Speed brakes are usually very small drag producers that provide energy
> control while at high indicated airspeeds. Once slowed to a low airspeed,
> speed brakes represent a very small portion of airframe drag. Sometimes,
> takeoff performance isn't even particularly degraded with the brakes
> extended.
>
>
Thanks for the info.
This type of speed brakes must be particular to some type of airplanes ?
High drag but bigger engine ?
I'm flying sleek airplanes with low over all drag when flaps are up, so
in my opinion, even you low drag brakes would make a difference with them.
Some slower airplanes with weak flap action, or even without flaps,
resort to speed brakes to increase drag during approach.
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Flap switches/relay wiring) |
On Aug 24, 2006, at 3:36 AM, Kevin Horton wrote:
>
>
> What happens if there is an accidental deployment during the
> landing flare?
Remember, this is a speed brake, not a spoiler. It increases drag but
has very little effect on lift. The effect of a speed brake decreases
as IAS decreases. The airplane slows down but not as much as at Vne.
I doubt that speed brake would really have any significant effect in
the landing flare.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>I have long ago given up trying to challenge every industry position. I do
>not have the time or interest to do so. When I do run across something in
>a design that is not consistent with the industry I do, and have
>investigated just what is different.
I don't think I suggested it. Obviously, industry
publishes a great deal of data that is need for
the make/buy/ignore decision along with information
vital to integrating a device into a new design.
Challenges are warranted when words taken from
what appears to be well grounded, widely distributed
ideas that cause readers to invest both $time$
and emotional capital for adoption of some product
or idea.
It's incumbent upon the astute designer (and advisor)
to evaluate and understand the return on investment. It's
not so much a challenge as it is a quest for understanding.
The unfortunate condition is that potential customers
are oft encouraged to spend $time$ on a product or activity
that fails to deliver . . . or delivers a feature that's
not really useful.
>The industry papers of the time were from relay manufacturers who had no
>reason to support one suppressor method or the other as they did not sell
>suppressors of any type (at the time) Their interest appeared to be to
>show how to get the most reliable use of their products which ranged from
>very small relays to huge ones and thus the recommendations were designed
>to be general and not always apply to any specific case.
Yup . . . the universe is long on generalized recipes
for success but it's not uncommon that such recipes are
short on detailed explanations for applicability and
return on investment . . .
>In the case of transorbs; many years ago I noted that a designer had used
>a diode and there were unwanted noise introduced into the system. It was
>determined that the opening delay and more important showed start to
>finish contact opening time was part of the problem. At that time I want
>into the EMI lab and with expert help we determined that part of the
>required fix was to quicken the opening contact time (not the delayed
>start of opening but the duration of contact opening).
>
>PART of the solution was replacing the Diode with a Transorb. There was
>more required that evolved contact arc suppression.
>
>The general conclusion was an across the board replacement of diodes with
>transorbs as it did not hurt and in rare cases prevent problems. No
>retrofit was made just new design used transorbs.
>
>I agree that your documented test of a small relay showed no significant
>time of contact opening but that is not necessarily so with power
>contactors seen in aircraft.
I tested battery contactors too.
Your decisions to take some action based on data
acquired during an investigation cannot be faulted
or argued with. At the same time, recommendation of
broad prescriptions for applying a design technique
because it mitigated a problem so specific as to
required detailed investigation is not good science
or business.
>Now in the case of experimental aircraft I have discovered one case the
>"B" lead contactor can require a transorb as a partial solution to contact
>arcing and continued arcing in one failure mode of the alternator.
Yup, but that's a new situation arising from an especially
antagonistic load switched by the contactor. Here the load
is not inductive, resistive, or lamp . . . it's an engine
driven energy source with dynamics that were never considered
when all the coil suppression techniques were crafted and
described in the oft cited documents. I.e., those documents
have almost no significance for solving the problem.
>I only intended to point out that case not make a big deal of it.
I wasn't making a big deal out of it either. My offering
was in response to recommendations were made based on
no better data than one gets for choosing laundry
soap because it says "new and improved" on the box.
> BTW I am not the only you have gotten up set with but perhaps the most
> memorable.
Really? Perhaps I need to be more skilled with the
use of emoticons . . . Folks often misinterpret my state
of being. When I am really upset about something, I'll
make it known. When someone offers an opinion about
things I've said or done, the input falls in one of
two categories (1) it's a valid observation worthy of
consideration and modification of future action - i.e.
good critical review -OR- (2) "noise" that contains
no data and should be ignored so that attention to
simple-ideas is not distracted or diluted. It's relatively
easy to make that determination without emotional
investment. But I've readily admitted to being really
wound up when individuals insert themselves between me and
my customers such that I am deprived of the opportunity
to keep them satisfied with their decision to use my
products and services.
Bob . . .
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | flap deployment above Vfe |
There seems to be some worry about flap deployment above Vfe.
Remember, Vfe is for *full* flap deployment. Most aircraft can deploy
partial flaps at much higher speeds. I used to deploy a small amount
of flaps on my RV-4 to help me slow down in a pinch.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>
>Yes I remember that interchange and its a wonderful example how selective
>cut and paste can change what I was saying and its context.
>
>Its a masterpiece.
>
>Paul
Really? There was no intention on my part to distort
any meaning in your words. If there was distortion,
it was accidental. I'd be pleased to supply you the
original for any editing you might wish to do that
would clarify of your intent.
Bob . . .
---------------------------------------------------------
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
---------------------------------------------------------
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring) |
Brian and all,
> I doubt that speed brake would really have any significant effect in
> the landing flare.
Yes they have. Used them on a Citation to shorten the float and firmly
plant the wheels on landing.
Now, what if the flare is a bit high and slow, or balloons, and a white
knuckle pilot actuates the speed-brakes ? Macho contact with Mother
Earth at best....
Best regards,
Gilles, no speed-brakes
http://contrails.free.fr
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: and relay coil spike suppression |
>
>You missed my point and I am sorry.
>
>I was looking for a statement from industry where the uni-directional
>transorb was NOT to be used. That its not mentioned to me says its OK as
>it is really a zener or a simple diode if properly connected and the
>voltage ratings recognized.
>
>I know of no such statement as while it may be a silly application it will
>work just fine.
I guess I misunderstood the term "work". If one selects a zener
diode for some application, it's easy to assume that the designer
needs the functionality of the device as a zener.
>I was expecting a simple " its a stupid application but you are right"
>from you.
I thought we were discussing the pros/cons of recommended
techniques and the idea that your argument was offered as
an off-topic ringer didn't occur to me. You wrote:
>Please tell the LIST (specific link please) where a 50V uni-directional
>Transorb device (properly connected) is different from a 50v diode
>in coil suppression or forward conduction for that matter.
>Of course if you use a Transorb alone as a diode its no better
>than a diode so that configuration is not addressed.
I missed the significance of the last sentence so
I went off and crafted . . .
http://www.aeroelectric.com/temp/Relay_Coil_Suppression.pdf
which illustrates the point. My suggestion is that
thrashing this little tid-bit added no value for those
who choose to follow this thread. I will offer the following
revision to what I wrote to wit:
WAS: "In fact, you cannot use a uni-directional Transorb (or
plain vanilla zener) unless combined with a diode to
prevent forward conduction as shown in multitudes of
catalogs and literature on relays."
NOW: There is no practical value in utilization of a single
unidirectional Transorb (or plain vanilla zener) because
its functionality is limited to behavior that mimics
the use of an ordinary diode as illustrated in cases
3/4 and 5/6 in the link cited above.
The industry wide practice for using a zener
in the coil suppression network of relays is illustrated
in cases 7/8 were the zener is turned over and a
diode added to prevent forward conduction. In this
instance, the zener's unique qualities as a voltage
clamping device provide the desired spike suppression
characteristics while minimizing effects on relay
drop out delay.
Bob . . .
________________________________________________________________________________
| From: | dsvs(at)comcast.net |
| Subject: | Re: flap deployment above Vfe |
Brian,
In addition to your comment, I would add that the flap deployment takes some time.
If one accidently touches the flap switch (the kind mounted on the sticck)
the flaps would only deploy slightly unless the pilot held the switch down.
This would go beyound accidental deployment. There is also a notable reaction
to deployment of flaps, and unless the pilot was overloade to the point of not
having situational awareness should note that the flaps are being deployed.
This will not stop every inadvertant flap deployment, but I doubt that the situation
is any where as common or dangerous as some imply. Don
-------------- Original message ----------------------
From: Brian Lloyd <brian-av(at)lloyd.com>
>
> There seems to be some worry about flap deployment above Vfe.
> Remember, Vfe is for *full* flap deployment. Most aircraft can deploy
> partial flaps at much higher speeds. I used to deploy a small amount
> of flaps on my RV-4 to help me slow down in a pinch.
>
> Brian Lloyd 361 Catterline Way
> brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
> +1.916.367.2131 (voice) +1.270.912.0788 (fax)
>
> I fly because it releases my mind from the tyranny of petty things . . .
> Antoine de Saint-Exupry
>
>
>
>
>
>
>
>
________________________________________________________________________________
| From: | OldBob Siegfried <oldbob(at)BeechOwners.com> |
| Subject: | Re: flap deployment above Vfe |
Good Morning Don,
All that you say makes sense, but I fail to see the
advantage to having so many switches on the control
stick.
In fact, I don't see the need for many of them to be
on the throttle either.
I like having a trim switch on the control stick or
wheel.
I think a transmit button there is very handy, but I
like it even better on the throttle! I do like the
idea of having an Ident button on the stick, but I
have never had one so mounted. May not be worth the
trouble.
An autopilot disconnect switch on the control unit
makes sense, but most autopilots can be easily
overridden if that becomes necessary.
My thought is to keep the number of switches on the
stick to the absolute minimum and and place the other
needed control devices in a comfortable position
relative to my throttle hand.
Isn't it great that we have the choice?
Happy Skies,
Old Bob
AKA
Bob Siegfried
Stearman N3977A
Downers Grove, Illinois
--- dsvs(at)comcast.net wrote:
> dsvs(at)comcast.net
>
> Brian,
> In addition to your comment, I would add that the
> flap deployment takes some time. If one accidently
> touches the flap switch (the kind mounted on the
> sticck) the flaps would only deploy slightly unless
> the pilot held the switch down. This would go
> beyound accidental deployment. There is also a
> notable reaction to deployment of flaps, and unless
> the pilot was overloade to the point of not having
> situational awareness should note that the flaps are
> being deployed. This will not stop every
> inadvertant flap deployment, but I doubt that the
> situation is any where as common or dangerous as
> some imply. Don
> -------------- Original message
> ----------------------
> From: Brian Lloyd <brian-av(at)lloyd.com>
> Lloyd
> >
> > There seems to be some worry about flap deployment
> above Vfe.
> > Remember, Vfe is for *full* flap deployment. Most
> aircraft can deploy
> > partial flaps at much higher speeds. I used to
> deploy a small amount
> > of flaps on my RV-4 to help me slow down in a
> pinch.
> >
> > Brian Lloyd 361 Catterline
> Way
> > brian HYPHEN av AT lloyd DOT com Folsom, CA
> 95630
> > +1.916.367.2131 (voice)
> +1.270.912.0788 (fax)
> >
> > I fly because it releases my mind from the tyranny
> of petty things . . .
> > Antoine de Saint-Exupry
> >
> >
> >
> >
> >
> >
> >
> >
>
>
>
>
> browse
> Subscriptions page,
> FAQ,
> http://www.matronics.com/Navigator?AeroElectric-List
>
> Web Forums!
>
>
> Admin.
>
>
>
>
>
________________________________________________________________________________
| From: | Michael Pereira <mjpnj(at)yahoo.com> |
| Subject: | Re: AeroElectric-List Digest: 31 Msgs - 08/23/06 |
Hey Paul,
> Yes I remember that interchange and its a wonderful example how selective
> cut and paste can change what I was saying and its context.
You know, Paul, it's clear that both you and Bob know more about electronics
than I could ever know or for that matter probably would ever want to know.
The thing is in Bob's posts he writes in such a way that dang near 100% of
it makes sense to a electronics near-luddite like me. In addition, his
explanations tend to highlight the underlying basic concepts well enough that
I can start to figure out other things for myself. People with high technical
skills that can actually teach are rare, those that are willing to do it for
peanuts are almost non-existant.
The only thing I've gotten out of this diode vs transorb thingy is that a
transorb may be like a diode and zener together or two zener's back to back.
It seems that even if it's technically better we're probably talking about a 1%
optimization. Even I'm not anal enough to worry about that small an improvement.
My understanding of the purpose of this list is to help people setup their
electrical systems in their homebuilt airplanes. This diode vs transorb,
transorb vs crowbar mental masturbation has contributed nothing to my understanding
of how to setup a homebuilt. It could be that i'm just stupid (but I suspect not)
and that it's greatly helped other members on the list, I just don't know.
I know Bob invites a high level of debate but i'm at a lost of why you continue
to post when on one hand you accuse Bob of twisting your arguments through editing
and on the other hand you're looking for his approval in other posts. ie paraphrasing
-
"i know it's a silly application but I expected you to tell me i was right".
Please make your posts more constructive if you want mere mortals like me to respect
your opinion.
> Its a masterpiece.
> Paul
c'ya,
Mike
__________________________________________________
________________________________________________________________________________
| From: | "Bill Denton" <bdenton(at)bdenton.com> |
| Subject: | flap deployment above Vfe |
"If one accidently touches the flap switch (the kind mounted on the sticck)
the flaps would only deploy slightly unless the pilot held the switch down."
That is not necessarily correct...
With many of the "flap controllers" which have been previously mentioned,
each "bump" of the flap switch lowers the flaps a pre-programmed amount.
For example the first "bump" would take the flaps to 10 degrees, the next
"bump" to 20 degrees, another "bump" to 30 degrees. And typically, a single
"bump" on the "up" switch fully retracts the flaps.
And at least one of these controllers can be programmed to automatically
adjust pitch trim as flaps are deployed/retracted.
So, even a little carelessness could cause a quick and possibly dangerous
reconfiguration of the aircraft...
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
dsvs(at)comcast.net
Sent: Thursday, August 24, 2006 10:32 AM
Subject: Re: AeroElectric-List: flap deployment above Vfe
Brian,
In addition to your comment, I would add that the flap deployment takes some
time. If one accidently touches the flap switch (the kind mounted on the
sticck) the flaps would only deploy slightly unless the pilot held the
switch down. This would go beyound accidental deployment. There is also a
notable reaction to deployment of flaps, and unless the pilot was overloade
to the point of not having situational awareness should note that the flaps
are being deployed. This will not stop every inadvertant flap deployment,
but I doubt that the situation is any where as common or dangerous as some
imply. Don
-------------- Original message ----------------------
From: Brian Lloyd <brian-av(at)lloyd.com>
>
> There seems to be some worry about flap deployment above Vfe.
> Remember, Vfe is for *full* flap deployment. Most aircraft can deploy
> partial flaps at much higher speeds. I used to deploy a small amount
> of flaps on my RV-4 to help me slow down in a pinch.
>
> Brian Lloyd 361 Catterline Way
> brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
> +1.916.367.2131 (voice) +1.270.912.0788 (fax)
>
> I fly because it releases my mind from the tyranny of petty things . . .
> Antoine de Saint-Exupry
>
>
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
couple of snips
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Thursday, August 24, 2006 7:46 AM
Subject: Re: AeroElectric-List: Re: MOV's
> At the same time, recommendation of
> broad prescriptions for applying a design technique
> because it mitigated a problem so specific as to
> required detailed investigation is not good science
> or business.
Sorry but in business documentation and stocking two parts when one is only
needed is sound business decisions. In aerospace its thousands of dollars
saved, just on the paperwork etc. In this case either part cost over $50
each. 10 cents for the part and $49.90 for screening, packaging,
identifying, paper etc etc.
There was no way to determine how often a specific case might pop up where
the transorb might be required and if one happened again the $20,000 spent
on analysis of the first problem might be repeated for no good reason. If I
had not taken action to switch from a diode to the transorb (across the
board) and another similar problem came up there would have been hell to pay
directed at me.
I do not think it was bad science (but GOOD science) to use a better or more
universal product and it clearly was the right business decision
When we found a better solution we jumped to use it. Thus my dismay at your
hard rejection of using a part that is equal or better than a diode. Perhaps
its that my background is different where no failure is acceptable and a
design error typically can cost more that the typical light aircraft.
I have an example as you like to tell. A satellite system had a minor
electrical design change that required a simple one line change ( in 6
places) in the automated system level test. One of the 6 was missed and the
cost was over $1,500,000 in hardware damage.
To a large extent it applies everywhere as the transorb vs the diode is a
clear cut case of the transorb always works and the diode usually always
works.
Perhaps I missed it but I do not recall you ever saying the transorb was bad
just that a diode was good enough or the transorb was not required based on
your knowledge and experience.
My point is the transorb is more universal and can help with unsuspecting
cases now and the future when new technology might produce issues we cannot
think of right now..
Surely at 15 cents each its not cost that is a factor here.
snip------------------------------
>> BTW I am not the only you have gotten up set with but perhaps the most
>> memorable.
>
> But I've readily admitted to being really
> wound up when individuals insert themselves between me and
> my customers such that I am deprived of the opportunity
> to keep them satisfied with their decision to use my
> products and services.
>
> Bob . . .
Here I was given the decision of either not reporting the failures at all or
protecting the owners demands of not being quoted by name. I do not like
being in the middle but I felt then (and now) its better to report problems
(specifically when it appears to be a basic design problem) than not say
anything IF that is the only two choices available.
The "customers" had already decided to not use that product anymore even if
you gave them a replacement as well in that case a new alternator and paid
the cleaning bill for their pants.
In this case it was the home built version of the OV crowbar (per your
plans) that false tripped and often damages the GOOD alternator when the "B"
lead contactor opened. Old news now as you have changed the design. I first
determined that when I built two my self it false tripped 100% of the time
when I tested it. See my recent post on contact bounce and the transient I
found on a full up mockup of an aircraft electrical system. BTW My OV crow
bar was on a 1" by 1.5" pcb so no long leads etc.
I ask you which is better. No feed back at all? or second hand feedback? I
suggest that second hand feedback often results in others willing to be
known by name and to step forward. IT was as I recall this that eventually
led to the redesign. Personally I do not like the design concept of the use
of a crowbar as used in this case so I was not interested in fixing what I
felt and continue to feel is the wrong approach to the problem but that is
an issue I do not wish to discuss here or in the future.
I have now decided not to report any second hand failures of your products
to you or the list however, because of your response to me in the past with
these reports.
In any event I suggest we drop the subjects and move on.
Paul
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
Its history and best left alone.
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Thursday, August 24, 2006 7:50 AM
Subject: Re: AeroElectric-List: Re: MOV's
>
>
>
>>
>>
>>Yes I remember that interchange and its a wonderful example how selective
>>cut and paste can change what I was saying and its context.
>>
>>Its a masterpiece.
>>
>>Paul
>
> Really? There was no intention on my part to distort
> any meaning in your words. If there was distortion,
> it was accidental. I'd be pleased to supply you the
> original for any editing you might wish to do that
> would clarify of your intent.
>
> Bob . . .
>
>
> ---------------------------------------------------------
> < What is so wonderful about scientific truth...is that >
> < the authority which determines whether there can be >
> < debate or not does not reside in some fraternity of >
> < scientists; nor is it divine. The authority rests >
> < with experiment. >
> < --Lawrence M. Krauss >
> ---------------------------------------------------------
>
>
>
________________________________________________________________________________
| From: | wgill10(at)comcast.net |
| Subject: | Re: AeroElectric-List Digest: 31 Msgs - 08/23/06 |
I concur...we're not bulding rocket launchers here.
Bill
-------------- Original message --------------
From: Michael Pereira <mjpnj(at)yahoo.com>
>
> Hey Paul,
>
> > Yes I remember that interchange and its a wonderful example how selective
> > cut and paste can change what I was saying and its context.
>
> You know, Paul, it's clear that both you and Bob know more about electronics
> than I could ever know or for that matter probably would ever want to know.
>
> The thing is in Bob's posts he writes in such a way that dang near 100% of
> it makes sense to a electronics near-luddite like me. In addition, his
> explanations tend to highlight the underlying basic concepts well enough that
> I can start to figure out other things for myself. People with high technical
> skills that can actually teach are rare, those that are willing to do it for
> peanuts are almost non-existant.
>
> The only thing I've gotten out of this diode vs transorb thingy is that a
> transorb may be like a diode and zener together or two zener's back to back.
> It seems that even if it's technically better we're probably talking about a
1%
> optimization. Even I'm not anal enough to worry about that small an improvement.
>
> My understanding of the purpose of this list is to help people setup their
> electrical systems in their homebuilt airplanes. This diode vs transorb,
> transorb vs crowbar mental masturbation has contributed nothing to my
> understanding
> of how to setup a homebuilt. It could be that i'm just stupid (but I suspect
> not)
> and that it's greatly helped other members on the list, I just don't know.
>
> I know Bob invites a high level of debate but i'm at a lost of why you continue
> to post when on one hand you accuse Bob of twisting your arguments through
> editing
> and on the other hand you're looking for his approval in other posts. ie
> paraphrasing -
> "i know it's a silly application but I expected you to tell me i was right".
>
> Please make your posts more constructive if you want mere mortals like me to
> respect
> your opinion.
>
> > Its a masterpiece.
>
> > Paul
>
> c'ya,
> Mike
>
> __________________________________________________
>
>
>
>
I concur...we're not bulding rocket launchers here.
Bill
> --> AeroElectric-List message posted
by: Michael Pereira
>
> Hey Paul,
>
>
> Yes I remember that interchange and its a wonderful example how selective
> > cut and paste can change what I was saying and its context.
>
> You know, Paul, it's clear that both you and Bob know more
about electronics
> than I could ever know or for that matter probably
would ever want to know.
>
> The thing is in Bob's posts he
writes in such a way that dang near 100% of
> it makes sense to a electronics
near-luddite like me. In addition, his
> explanations tend to highlight
the underlying basic concepts well enough that
> I can start to
figure out other things for myself. People with high
techn
ical
> skills that can actually teach are rare, those that are willing to
do it for
> peanuts are almost non-existant.
>
> The only
thing I've gotten out of this diode vs transorb thingy is that a
> transorb
may be like a diode and zener together or two zener's back to back.
>
It seems that even if it's technically better we're probably talking about
a 1%
> optimization. Even I'm not anal enough to worry about that small
an improvement.
>
> My understanding of the purpose of this
list is to help people setup their
> electrical systems in their homebuilt
airplanes. This diode vs transorb,
> transorb vs crowbar mental masturbation
has contributed nothing to my
> understanding
> of how
to setup a homebuilt. It could be that i'm just stupid (but I suspect
>
not)
> and that it's greatly helped other members on the list, I just
don't know.
>
> I know Bob invites a
high l
Q,
________________________________________________________________________________
| From: | dsvs(at)comcast.net |
| Subject: | Re: flap deployment above Vfe |
Bob,
I was not trying to justify the addition of any switch to the stick, just commenting
on the overblown percieved danger of such a switch. And yes it is great
that we have the choices. Don
-------------- Original message ----------------------
From: OldBob Siegfried <oldbob(at)BeechOwners.com>
>
>
> Good Morning Don,
>
> All that you say makes sense, but I fail to see the
> advantage to having so many switches on the control
> stick.
>
> In fact, I don't see the need for many of them to be
> on the throttle either.
>
> I like having a trim switch on the control stick or
> wheel.
>
> I think a transmit button there is very handy, but I
> like it even better on the throttle! I do like the
> idea of having an Ident button on the stick, but I
> have never had one so mounted. May not be worth the
> trouble.
>
> An autopilot disconnect switch on the control unit
> makes sense, but most autopilots can be easily
> overridden if that becomes necessary.
>
> My thought is to keep the number of switches on the
> stick to the absolute minimum and and place the other
> needed control devices in a comfortable position
> relative to my throttle hand.
>
> Isn't it great that we have the choice?
>
> Happy Skies,
>
> Old Bob
> AKA
> Bob Siegfried
> Stearman N3977A
> Downers Grove, Illinois
>
> --- dsvs(at)comcast.net wrote:
>
> > dsvs(at)comcast.net
> >
> > Brian,
> > In addition to your comment, I would add that the
> > flap deployment takes some time. If one accidently
> > touches the flap switch (the kind mounted on the
> > sticck) the flaps would only deploy slightly unless
> > the pilot held the switch down. This would go
> > beyound accidental deployment. There is also a
> > notable reaction to deployment of flaps, and unless
> > the pilot was overloade to the point of not having
> > situational awareness should note that the flaps are
> > being deployed. This will not stop every
> > inadvertant flap deployment, but I doubt that the
> > situation is any where as common or dangerous as
> > some imply. Don
> > -------------- Original message
> > ----------------------
> > From: Brian Lloyd <brian-av(at)lloyd.com>
> > Lloyd
> > >
> > > There seems to be some worry about flap deployment
> > above Vfe.
> > > Remember, Vfe is for *full* flap deployment. Most
> > aircraft can deploy
> > > partial flaps at much higher speeds. I used to
> > deploy a small amount
> > > of flaps on my RV-4 to help me slow down in a
> > pinch.
> > >
> > > Brian Lloyd 361 Catterline
> > Way
> > > brian HYPHEN av AT lloyd DOT com Folsom, CA
> > 95630
> > > +1.916.367.2131 (voice)
> > +1.270.912.0788 (fax)
> > >
> > > I fly because it releases my mind from the tyranny
> > of petty things . . .
> > > Antoine de Saint-Exupry
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
> >
> > browse
> > Subscriptions page,
> > FAQ,
> > http://www.matronics.com/Navigator?AeroElectric-List
> >
> > Web Forums!
> >
> >
> > Admin.
> >
> >
> >
> >
> >
>
>
>
>
>
________________________________________________________________________________
| From: | dsvs(at)comcast.net |
| Subject: | flap deployment above Vfe |
Mabe so but these usually have the control circuit built into the switch and that
precludes stich mounting them.
-------------- Original message ----------------------
From: "Bill Denton" <bdenton(at)bdenton.com>
>
> "If one accidently touches the flap switch (the kind mounted on the sticck)
> the flaps would only deploy slightly unless the pilot held the switch down."
>
> That is not necessarily correct...
>
> With many of the "flap controllers" which have been previously mentioned,
> each "bump" of the flap switch lowers the flaps a pre-programmed amount.
>
> For example the first "bump" would take the flaps to 10 degrees, the next
> "bump" to 20 degrees, another "bump" to 30 degrees. And typically, a single
> "bump" on the "up" switch fully retracts the flaps.
>
> And at least one of these controllers can be programmed to automatically
> adjust pitch trim as flaps are deployed/retracted.
>
> So, even a little carelessness could cause a quick and possibly dangerous
> reconfiguration of the aircraft...
>
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
> dsvs(at)comcast.net
> Sent: Thursday, August 24, 2006 10:32 AM
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: flap deployment above Vfe
>
>
>
> Brian,
> In addition to your comment, I would add that the flap deployment takes some
> time. If one accidently touches the flap switch (the kind mounted on the
> sticck) the flaps would only deploy slightly unless the pilot held the
> switch down. This would go beyound accidental deployment. There is also a
> notable reaction to deployment of flaps, and unless the pilot was overloade
> to the point of not having situational awareness should note that the flaps
> are being deployed. This will not stop every inadvertant flap deployment,
> but I doubt that the situation is any where as common or dangerous as some
> imply. Don
> -------------- Original message ----------------------
> From: Brian Lloyd <brian-av(at)lloyd.com>
> >
> > There seems to be some worry about flap deployment above Vfe.
> > Remember, Vfe is for *full* flap deployment. Most aircraft can deploy
> > partial flaps at much higher speeds. I used to deploy a small amount
> > of flaps on my RV-4 to help me slow down in a pinch.
> >
> > Brian Lloyd 361 Catterline Way
> > brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
> > +1.916.367.2131 (voice) +1.270.912.0788 (fax)
> >
> > I fly because it releases my mind from the tyranny of petty things . . .
> > Antoine de Saint-Exupry
> >
> >
> >
> >
> >
> >
> >
> >
>
>
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
| Subject: | Re: flap deployment above Vfe |
Bob and all,
I sure do agree with your whole message.
Just a question.
> I do like the
> idea of having an Ident button on the stick, but I
> have never had one so mounted. May not be worth the
> trouble.
>
I'm not familiar with US ATC, but is the Ident button used so often ?
After all, once you've displayed your XPDR code and the controller sees
you on his radar, what is the point in pushing ident again and again ?
And he (she) would not ask you to Ident while you're performing some
delicate maneuver, would he (or she) ?
Or am I missing something ?
> My thought is to keep the number of switches on the
> stick to the absolute minimum and and place the other
> needed control devices in a comfortable position
> relative to my throttle hand.
>
> Isn't it great that we have the choice?
>
Regards,
Gilles
http://contrails.free.fr
________________________________________________________________________________
| From: | OldBob Siegfried <oldbob(at)BeechOwners.com> |
| Subject: | Re: flap deployment above Vfe |
Good Afternoon Gilles,
I think my comment to your comment will be:
It All Depends!
Most of my Stearman flying is VFR in the local Chicago
area. Every time I go to a local towered airport, I
will be asked to ident.
On very rare occasions when IFR, I will be asked to
ident when changing from one control center to
another. That doesn't happen anywhere near as often as
it did twenty to thirty years ago.
I am sure that the need for an ident is somewhat
variable depending on the area being flown and whether
or not the aircraft is in continuous contact with
officialdom. I tend to fly VFR with no flight plan and
no flight following whenever that is practical.
Therefore, anytime I do decide to join into the
"system" I will almost always be asked for an ident.
However, it doesn't happen often enough such that I
would make much effort to add that capability to my
control column!
Happy Skies,
Old Bob
--- Gilles Thesee <Gilles.Thesee@ac-grenoble.fr>
wrote:
> Thesee <Gilles.Thesee@ac-grenoble.fr>
>
> Bob and all,
>
> I sure do agree with your whole message.
> Just a question.
>
> > I do like the
> > idea of having an Ident button on the stick, but I
> > have never had one so mounted. May not be worth
> the
> > trouble.
> >
> I'm not familiar with US ATC, but is the Ident
> button used so often ?
> After all, once you've displayed your XPDR code and
> the controller sees
> you on his radar, what is the point in pushing ident
> again and again ?
> And he (she) would not ask you to Ident while you're
> performing some
> delicate maneuver, would he (or she) ?
> Or am I missing something ?
>
> > My thought is to keep the number of switches on
> the
> > stick to the absolute minimum and and place the
> other
> > needed control devices in a comfortable position
> > relative to my throttle hand.
> >
> > Isn't it great that we have the choice?
> >
> Regards,
> Gilles
> http://contrails.free.fr
>
>
>
>
> browse
> Subscriptions page,
> FAQ,
> http://www.matronics.com/Navigator?AeroElectric-List
>
> Web Forums!
>
>
> Admin.
>
>
>
>
>
________________________________________________________________________________
| Subject: | flap deployment above Vfe |
| From: | "Lloyd, Daniel R." <LloydDR(at)wernerco.com> |
The aircraft extra FPS system does not, it allows the builder to wire whatever
switch they want, including a grip switch, but what they do have is an airspeed
cutout, and this would solve it when in cruise but not during approach.
Dan
40269
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of dsvs(at)comcast.net
Sent: Thursday, August 24, 2006 12:56 PM
Subject: RE: AeroElectric-List: flap deployment above Vfe
Mabe so but these usually have the control circuit built into the switch and that
precludes stich mounting them.
-------------- Original message ----------------------
From: "Bill Denton" <bdenton(at)bdenton.com>
>
> "If one accidently touches the flap switch (the kind mounted on the sticck)
> the flaps would only deploy slightly unless the pilot held the switch down."
>
> That is not necessarily correct...
>
> With many of the "flap controllers" which have been previously mentioned,
> each "bump" of the flap switch lowers the flaps a pre-programmed amount.
>
> For example the first "bump" would take the flaps to 10 degrees, the next
> "bump" to 20 degrees, another "bump" to 30 degrees. And typically, a single
> "bump" on the "up" switch fully retracts the flaps.
>
> And at least one of these controllers can be programmed to automatically
> adjust pitch trim as flaps are deployed/retracted.
>
> So, even a little carelessness could cause a quick and possibly dangerous
> reconfiguration of the aircraft...
>
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
> dsvs(at)comcast.net
> Sent: Thursday, August 24, 2006 10:32 AM
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: flap deployment above Vfe
>
>
>
> Brian,
> In addition to your comment, I would add that the flap deployment takes some
> time. If one accidently touches the flap switch (the kind mounted on the
> sticck) the flaps would only deploy slightly unless the pilot held the
> switch down. This would go beyound accidental deployment. There is also a
> notable reaction to deployment of flaps, and unless the pilot was overloade
> to the point of not having situational awareness should note that the flaps
> are being deployed. This will not stop every inadvertant flap deployment,
> but I doubt that the situation is any where as common or dangerous as some
> imply. Don
> -------------- Original message ----------------------
> From: Brian Lloyd <brian-av(at)lloyd.com>
> >
> > There seems to be some worry about flap deployment above Vfe.
> > Remember, Vfe is for *full* flap deployment. Most aircraft can deploy
> > partial flaps at much higher speeds. I used to deploy a small amount
> > of flaps on my RV-4 to help me slow down in a pinch.
> >
> > Brian Lloyd 361 Catterline Way
> > brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
> > +1.916.367.2131 (voice) +1.270.912.0788 (fax)
> >
> > I fly because it releases my mind from the tyranny of petty things . . .
> > - Antoine de Saint-Exupry
> >
> >
> >
> >
> >
> >
> >
> >
>
>
>
>
>
>
>
>
>
>
>
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: AeroElectric-List Digest: 31 Msgs - 08/23/06 |
Interesting that this message (from Michael) never arrived at my computer.
And no you are not (building rocket launchers) but if there had been a
transorb on the aircraft bus (different application than the relay, but
another one of the Paul vs. Bob arguments (where Paul; says there is a
transient and Bob: says no because I have never seen one) where the
alternator was damaged by the defectively designed OV crow bar, dozens of
pilots would not have had to replace the alternator and remove the faulty OV
device. I recently posted a pix of a repeatable transient that 100% of the
time tripped the OV device falsely in my own testing.
As you may recall Vans strongly asked builders to REMOVE the OV device as it
was damaging the alternators with false trips. Told to me by the GM at Vans
at the time.
This was discussed at length a couple of years ago so there is no need to
recycle it now.
My point is on other lists a simple " yes a transorb as Eric suggests is a
safer way to go and a better solution". No need to get into a thrashing
session etc. That is as technical as it ever needed to get.
Paul
----- Original Message -----
From: wgill10(at)comcast.net
To: aeroelectric-list(at)matronics.com
Sent: Thursday, August 24, 2006 9:43 AM
Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 31 Msgs -
08/23/06
I concur...we're not bulding rocket launchers here.
Bill
-------------- Original message --------------
From: Michael Pereira <mjpnj(at)yahoo.com>
>
> Hey Paul,
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: and relay coil spike suppression |
The end.
Clearly you are unwilling to say the bi-transorb is just as good as a diode
and in some cases better.
Its time to say good by to this line of discussion
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Thursday, August 24, 2006 8:15 AM
Subject: AeroElectric-List: Re: and relay coil spike suppression
>
>
>
>>
>>
>>You missed my point and I am sorry.
>>
>>I was looking for a statement from industry where the uni-directional
>>transorb was NOT to be used. That its not mentioned to me says its OK as
>>it is really a zener or a simple diode if properly connected and the
>>voltage ratings recognized.
>>
>>I know of no such statement as while it may be a silly application it will
>>work just fine.
>
> I guess I misunderstood the term "work". If one selects a zener
> diode for some application, it's easy to assume that the designer
> needs the functionality of the device as a zener.
>
>
>>I was expecting a simple " its a stupid application but you are right"
>>from you.
>
> I thought we were discussing the pros/cons of recommended
> techniques and the idea that your argument was offered as
> an off-topic ringer didn't occur to me. You wrote:
>
> >Please tell the LIST (specific link please) where a 50V uni-directional
> >Transorb device (properly connected) is different from a 50v diode
> >in coil suppression or forward conduction for that matter.
>
> >Of course if you use a Transorb alone as a diode its no better
> >than a diode so that configuration is not addressed.
>
> I missed the significance of the last sentence so
> I went off and crafted . . .
>
> http://www.aeroelectric.com/temp/Relay_Coil_Suppression.pdf
>
> which illustrates the point. My suggestion is that
> thrashing this little tid-bit added no value for those
> who choose to follow this thread. I will offer the following
> revision to what I wrote to wit:
>
> WAS: "In fact, you cannot use a uni-directional Transorb (or
> plain vanilla zener) unless combined with a diode to
> prevent forward conduction as shown in multitudes of
> catalogs and literature on relays."
>
> NOW: There is no practical value in utilization of a single
> unidirectional Transorb (or plain vanilla zener) because
> its functionality is limited to behavior that mimics
> the use of an ordinary diode as illustrated in cases
> 3/4 and 5/6 in the link cited above.
>
> The industry wide practice for using a zener
> in the coil suppression network of relays is illustrated
> in cases 7/8 were the zener is turned over and a
> diode added to prevent forward conduction. In this
> instance, the zener's unique qualities as a voltage
> clamping device provide the desired spike suppression
> characteristics while minimizing effects on relay
> drop out delay.
>
> Bob . . .
>
>
>
________________________________________________________________________________
| From: | Kevin Horton <khorton01(at)rogers.com> |
| Subject: | Re: Flap switches/relay wiring) |
On 24 Aug 2006, at 10:43, Brian Lloyd wrote:
> av(at)lloyd.com>
>
>
> On Aug 24, 2006, at 3:36 AM, Kevin Horton wrote:
>
>>
>>
>> What happens if there is an accidental deployment during the
>> landing flare?
>
> Remember, this is a speed brake, not a spoiler. It increases drag
> but has very little effect on lift. The effect of a speed brake
> decreases as IAS decreases. The airplane slows down but not as much
> as at Vne. I doubt that speed brake would really have any
> significant effect in the landing flare.
Sorry, I thought that the Glasair installation was likely on the
wing, and its deployment would reduce the lift, as well as produce
extra drag. I was wondering if the loss of lift at low speed at a
critical flight phase could be a problem.
Air Canada had a fatal accident with a DC-8 at Toronto many, many
years ago. There was a screw up in the flight deck, which resulted
in the ground spoilers being deployed at about 60 ft AGL. No survivors.
http://aviation-safety.net/database/record.php?id=19700705-0
If the Glasair speedbrakes are not on the wing, then my original
question was not relevant.
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://www.kilohotel.com/rv8
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: flap deployment above Vfe |
Gilles Thesee wrote:
> I'm not familiar with US ATC, but is the Ident button used so often ?
No, it isn't. I just finished putting 75 hours on my Aztec in the last
two months. (Sacramento to Dominica via Texas and Florida, much flying
in Florida, and return to Sacramento via Texas and Boise.) Every flight
was "in the system". I made 20+ hops. I don't think I was asked to
"squawk IDENT" more than three or four times. You are correct in
assuming that once you enter your assigned code, ATC rarely requests
that you squawk IDENT.
BTW, the times I was asked to squawk IDENT were always on an initial
call-up and the facility or sector was trying to determine whether I was
in their airspace prior to assigning me a discrete code.
Like you, I see absolutely no need for an IDENT button my stick.
But ergonomics is an issue. Sure a button on the stick is convenient but
a button on the panel needn't be inconvenient. If you are building a
tandem aircraft think about locating your radios on the left side of
your panel so you can leave your right hand on the stick and can use
your left hand to manipulate the knobs. Likewise put your switches over
there too.
And think about putting your PTT on the throttle in a tandem aircraft.
That is how most military aircraft are configured. It may seem strange
at first but later it becomes very comfortable. That is now how I prefer
things.
Brian
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Flap switches/relay wiring) |
Kevin Horton wrote:
>> Remember, this is a speed brake, not a spoiler. It increases drag but
>> has very little effect on lift. The effect of a speed brake decreases
>> as IAS decreases. The airplane slows down but not as much as at Vne. I
>> doubt that speed brake would really have any significant effect in the
>> landing flare.
>
> Sorry, I thought that the Glasair installation was likely on the wing,
> and its deployment would reduce the lift, as well as produce extra
> drag. I was wondering if the loss of lift at low speed at a critical
> flight phase could be a problem.
Probably not as the speed brake tends to be well aft of the point of
maximum thickness and very little of the span. It has very little impact
on lift.
> Air Canada had a fatal accident with a DC-8 at Toronto many, many years
> ago. There was a screw up in the flight deck, which resulted in the
> ground spoilers being deployed at about 60 ft AGL. No survivors.
Yeah, well, the ground spoilers are supposed to kill ALL lift. That is a
completely different story.
>
> http://aviation-safety.net/database/record.php?id=19700705-0
>
> If the Glasair speedbrakes are not on the wing, then my original
> question was not relevant.
And even if they are, I think you will find they have very little effect
if deployed while in landing configuration.
Regardless, don't take my word for it. Be sure to try it yourself.
Brian
________________________________________________________________________________
| From: | OldBob Siegfried <oldbob(at)BeechOwners.com> |
| Subject: | Re: Flap switches/relay wiring) |
Good Afternoon Kevin,
This may have little or no bearing on the subject at
hand, but the DC-8 had no speed brake at all!
They originally designed one that came out of the
fuselage at the wing root. It was totally ineffective
and the design was too far along to incorporate a
speed brake in the wing structure. They fixed it by
making the engine reversers usable in flight. If you
wanted a speed brake function in the DC-8, you used
inflight thrust reversing.
They did employ ground spoilers which were designed to
kill as much lift as possible. They were located along
the trailing portion of the primary wing structure.
Speed brakes that are intended to provide inflight
drag tend to be mounted further forward on the wing
and be designed so they destroy very little of the
lift being developed by the wing. Obviously, there are
many variations. Boeing tends to use sections of the
trailing edge that also serve as ground spoilers The
Caravelle a had a beautiful set of brakes that looked
like big brothers of those used on gliders.
In general, the inflight speed brakes have a
relatively small effect on the lift being produced.
The ground spoilers are designed to kill as much of
the lift as is possible.
No doubt many of our listers can point to exceptions
where the functions are mixed even more so than on the
Boeings, but the DC-8 had NO speed brakes at all
within the aircraft structure. Just the inflight
reversing capability. That actually worked quite well.
but it sure made a lot of noise and a lot of
vibration!
Happy Skies,
Old (Once upon a time DC-8 captain) Bob
--- Kevin Horton wrote:
> Horton
>
> On 24 Aug 2006, at 10:43, Brian Lloyd wrote:
>
> Lloyd > av(at)lloyd.com>
> >
> >
> > On Aug 24, 2006, at 3:36 AM, Kevin Horton wrote:
> >
> Horton
> >>
> >>
> >> What happens if there is an accidental deployment
> during the
> >> landing flare?
> >
> > Remember, this is a speed brake, not a spoiler. It
> increases drag
> > but has very little effect on lift. The effect of
> a speed brake
> > decreases as IAS decreases. The airplane slows
> down but not as much
> > as at Vne. I doubt that speed brake would really
> have any
> > significant effect in the landing flare.
>
> Sorry, I thought that the Glasair installation was
> likely on the
> wing, and its deployment would reduce the lift, as
> well as produce
> extra drag. I was wondering if the loss of lift at
> low speed at a
> critical flight phase could be a problem.
>
> Air Canada had a fatal accident with a DC-8 at
> Toronto many, many
> years ago. There was a screw up in the flight deck,
> which resulted
> in the ground spoilers being deployed at about 60 ft
> AGL. No survivors.
>
>
http://aviation-safety.net/database/record.php?id=19700705-0
>
> If the Glasair speedbrakes are not on the wing, then
> my original
> question was not relevant.
>
> Kevin Horton RV-8 (finishing kit)
> Ottawa, Canada
> http://www.kilohotel.com/rv8
>
>
>
> browse
> Subscriptions page,
> FAQ,
> http://www.matronics.com/Navigator?AeroElectric-List
>
> Web Forums!
>
>
> Admin.
>
>
>
>
>
________________________________________________________________________________
| Subject: | Garmin GNS 530 Installation Manual |
| From: | "Bill Denton" <bdenton(at)bdenton.com> |
Does anyone know where I can find a .pdf of a Garmin GNS 530 Installation Manual?
Thanks!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=57097#57097
________________________________________________________________________________
| Subject: | Re: Flap switches/relay wiring) |
> In general, the inflight speed brakes have a
> relatively small effect on the lift being produced.
> The ground spoilers are designed to kill as much of
> the lift as is possible.
>
When on the wings, "drag only" speed-brakes tend to look like fences
lifted at a distance from the wing skin, in order to preserve the
airflow on the wing upper surface.
If they block part of the airflow on the wing, then they'll kill lift as
well as increase drag.
Regards,
Gilles
http://contrails.free.fr
________________________________________________________________________________
| Subject: | Re: Garmin GNS 530 Installation Manual |
>
> Does anyone know where I can find a .pdf of a Garmin GNS 530 Installation Manual?
>
> Thanks!
>
Have you tried
http://contrails.free.fr/gps_manuels.php ?
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: and relay coil spike suppression |
>
>The end.
>
>Clearly you are unwilling to say the bi-transorb is just as good as a
>diode and in some cases better.
>
>Its time to say good by to this line of discussion
My sincere apologies . . . if that's what you were arguing, then
no problem. I thought I made it clear that I had no argument with
using ANY of the coil suppression techniques suggested by a whole
variety of authors INCLUDING the bi-transorb, bi-filar coils, cap-resistor,
resistor, diode-zener, diode or any other technique one wishes to
embrace.
The sum and substance of my position was (and still is) that I can
demonstrate no reason for anyone to FAVOR any of those techniques over
the others for the purpose of increasing relay life. In particular,
I was objecting to a "new and improved" approach to selling coil
suppression when, like laundry soap, the ultimate choice of any
flavor would perform just fine. Under those circumstances, there's
no reason for anyone to jerk out existing technologies based on concerns
for shortened relay life . . . and similarly no reason not to
use the most inexpensive or convenient technology at hand. That's
what I meant by "practical value". Beyond that, anything that
floats your personal boat will work just fine too. My head is
always calculating the return-on-investment/cost-of-ownership
considerations so my personal boat floats just fine on diodes.
Bob . . .
________________________________________________________________________________
| From: | "Olen Goodwin" <ogoodwin(at)comcast.net> |
| Subject: | Re: Flap switches/relay wiring) |
Right you are about the DC8, Bob. I too flew it (about 12 years straight).
It always seemed an unnatural act to deliberately use reverse in flight....
An exception to what you say about speed brakes not having much effect on
lift is the Boeing 727, an all around wonderfully capable airplane. The
speed brakes (flight spoilers) were so effective you could actually lose
10,000 feet in less than 10 miles or slow from 350 IAS to 250 in about 4
miles, not something you'd want to do in a pax airplane (the descent
anyway), but lots of fun with boxes. Two fine airplanes, either of which I
wish I was still flying.
Olen Goodwin
----- Original Message -----
From: "OldBob Siegfried" <oldbob(at)BeechOwners.com>
Sent: Thursday, August 24, 2006 4:03 PM
Subject: Re: Ergonomics (was: AeroElectric-List: Flap switches/relay wiring)
>
>
>
> Good Afternoon Kevin,
>
> This may have little or no bearing on the subject at
> hand, but the DC-8 had no speed brake at all!
>
> They originally designed one that came out of the
> fuselage at the wing root. It was totally ineffective
> and the design was too far along to incorporate a
> speed brake in the wing structure. They fixed it by
> making the engine reversers usable in flight. If you
> wanted a speed brake function in the DC-8, you used
> inflight thrust reversing.
>
> They did employ ground spoilers which were designed to
> kill as much lift as possible. They were located along
> the trailing portion of the primary wing structure.
> Speed brakes that are intended to provide inflight
> drag tend to be mounted further forward on the wing
> and be designed so they destroy very little of the
> lift being developed by the wing. Obviously, there are
> many variations. Boeing tends to use sections of the
> trailing edge that also serve as ground spoilers The
> Caravelle a had a beautiful set of brakes that looked
> like big brothers of those used on gliders.
>
> In general, the inflight speed brakes have a
> relatively small effect on the lift being produced.
> The ground spoilers are designed to kill as much of
> the lift as is possible.
>
> No doubt many of our listers can point to exceptions
> where the functions are mixed even more so than on the
> Boeings, but the DC-8 had NO speed brakes at all
> within the aircraft structure. Just the inflight
> reversing capability. That actually worked quite well.
> but it sure made a lot of noise and a lot of
> vibration!
>
> Happy Skies,
>
> Old (Once upon a time DC-8 captain) Bob
>
> --- Kevin Horton wrote:
>
>> Horton
>>
>> On 24 Aug 2006, at 10:43, Brian Lloyd wrote:
>>
>> Lloyd > > av(at)lloyd.com>
>> >
>> >
>> > On Aug 24, 2006, at 3:36 AM, Kevin Horton wrote:
>> >
>> Horton
>> >>
>> >>
>> >> What happens if there is an accidental deployment
>> during the
>> >> landing flare?
>> >
>> > Remember, this is a speed brake, not a spoiler. It
>> increases drag
>> > but has very little effect on lift. The effect of
>> a speed brake
>> > decreases as IAS decreases. The airplane slows
>> down but not as much
>> > as at Vne. I doubt that speed brake would really
>> have any
>> > significant effect in the landing flare.
>>
>> Sorry, I thought that the Glasair installation was
>> likely on the
>> wing, and its deployment would reduce the lift, as
>> well as produce
>> extra drag. I was wondering if the loss of lift at
>> low speed at a
>> critical flight phase could be a problem.
>>
>> Air Canada had a fatal accident with a DC-8 at
>> Toronto many, many
>> years ago. There was a screw up in the flight deck,
>> which resulted
>> in the ground spoilers being deployed at about 60 ft
>> AGL. No survivors.
>>
>>
> http://aviation-safety.net/database/record.php?id=19700705-0
>>
>> If the Glasair speedbrakes are not on the wing, then
>> my original
>> question was not relevant.
>>
>> Kevin Horton RV-8 (finishing kit)
>> Ottawa, Canada
>> http://www.kilohotel.com/rv8
>>
>>
>>
>> browse
>> Subscriptions page,
>> FAQ,
>> http://www.matronics.com/Navigator?AeroElectric-List
>>
>> Web Forums!
>>
>>
>> Admin.
>>
>>
>>
>>
>>
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
From: "Paul Messinger" <paulm(at)olypen.com>
Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 31 Msgs -
08/23/06
Date: Thu, 24 Aug 2006 12:55:14 -0700
Sender: owner-aeroelectric-list-server(at)matronics.com
X-Antivirus: AVG for E-mail 7.1.394 [268.11.3/423]
Interesting that this message (from Michael) never arrived at my computer.
And no you are not (building rocket launchers) but if there had been a
transorb on the aircraft bus (different application than the relay, but
another one of the Paul vs. Bob arguments (where Paul; says there is a
transient and Bob: says no because I have never seen one) . . .
Correction: never been able to "capture" a starter induced
transient in spite of years of specific tests to see if such
animals exist . . . It wasn't as if I were standing around
waiting for one to walk by.
. . . where the alternator was damaged by the defectively designed OV
crow bar, dozens of pilots would not have had to replace the alternator and
remove the faulty OV device.
You know, it's difficult to "fix" anything when the people
having problems don't talk to the supplier of the "problem"
device. Out of about 4 thousand crowbar ov systems now in service
both OBAM and TC, we've been made aware of and fixed about
a dozen cases in the past 20 years. Two of the situations
revealed new data that prompted changes to the design.
I recently posted a pix of a repeatable transient that 100% of the time
tripped the OV device falsely in my own testing.
Yeah, some fuzzy scope traces with no test setup data
and no description of the test procedure. No definition
of the OV device in question. Obviously no contact with
the original designer in any spirit of curiosity or
helpful transfer of useful data. How am I or anyone else
to interpret what you've shared? How do we make use of
this data to improve on any design?
As you may recall Vans strongly asked builders to REMOVE the OV device as
it was damaging the alternators with false trips. Told to me by the GM at
Vans at the time.
This was discussed at length a couple of years ago so there is no need to
recycle it now.
You have just recycled it yourself, not as a point of
useful information but as a hammer with an intent to
injure . . .
My point is on other lists a simple " yes a transorb as Eric suggests is a
safer way to go and a better solution". No need to get into a thrashing
session etc. That is as technical as it ever needed to get.
Hmmmm "safer" . . . does it also ward of evil demons and
bird flu?
That sir is an excellent example of your lack of understanding
and re-enforces the notion I've long suspected that your
participation in this discussion has little to do with
the art and science of building airplanes and a much to
do with attempts to discredit me. Since you can't win
with logic and good science, you're now reduced to dragging
out old canards.
The alternators in question were failed due to load-dump
effected by b-lead disconnection for one of TWO reasons.
(1) the pilot operated the alternator ON-OFF switch
while the alternator was under load . . .
-OR-
(2) the ov system tripped for what-ever reason and
opened the b-lead contactor.
These events would have taken place irrespective of
the technology behind the OV sensing and control. If
it had been a simple zener-comparator that was overexcited
and had dumped the relay, the end result would have been
the same. You have, and continue to denigrate my work
with exaggeration and hyperbole and never offered to
assist in chasing out any bugs, real or imagined.
So the "fix" was to bury heads in the sand and state
our internally regulated alternators never fail in an
runaway condition so we'll take that pesky control system
off.
Vans (like your mythical disgruntled AeroElectric
Connection customers) never bothered to contact me about
their problems whereupon they would have been greeted
with instant cooperative and enthusiastic assistance or
at least a refund of their money. It's this kind of
communication and cooperation that makes things BETTER.
Instead, I hear about the problems from you when you
wave the news around to re-enforce your obviously
dismal opinions of me.
Permit me to offer a calm and well considered opinion
based on years of observations (and dodging your
mudballs). Hmmmm . . . I wonder if you remember your
very first phone call to me a long time ago where
I got a very agitated claim that you'd tried to order
my book several times and you were tired of being
ignored. As I recall, I could not find your order(s)
in the system but shipped you a free book anyhow.
Now here we are, 12-15 years later and you're still
accusing me of disrespect, incompetence, dishonorable
behavior, and any number of evil traits.
A couple of years ago you (and Eric as I recall) went
off to do some tests. I was delighted with the notion that
kindred spirits with an interest in promoting OBAM
aviation had the tools and time to get some badly needed
data for the purposes of improving upon the best-we-know-
how-to-do. At least here on the List, nothing came out
of those tests but ammunition for attacking what had gone
before . . . and contributed nothing to what could go
on in the future.
So now we come to it. You are not a teacher sir, you
explain nothing. Your factual contributions to the list
have been limited and punctuated with reports (which
I will now call fabricated) of how unhappy or abused my
customers are. You've never offered critical review
of my work based on your own knowledge and understanding.
You've supported your version of "science" with references
to the work of others and never with work of your own.
Your demonstrated behavior is the engineering manager's
worst nightmare: lot's of noise, manufactured discontent
and and zero work-product that one would be proud to pass
along to a paying customer. Your conduct here on the List
is demonstrably contrary to the spirit and intent of those
who gather here to learn, to be of assistance to others
and to advance the state of our art and science.
On behalf of my customers to spend their $time$ to exploit
my $time$, talent and resources . . . and for myself
now weary of the joust . . . I will ask in what I assure
you is a very calm and most polite tone to please vacate
the AeroElectric-List.
Bob . . .
________________________________________________________________________________
| From: | "Michael Hinchcliff" <cfi(at)conwaycorp.net> |
Can somebody tell me where I can buy a single Nexus TJT-102 also known
as a M9177/4-1 female adapter? These are used by
Allied-Signal/Honeywell panel-mounted GPS products as a data loader
port. I have the PC data cable with the male end, but I need the female
end to mount in the instrument panel. I contacted the manufacturer and
they won't sell me less than 50 at a time. Their direct distributors
are the same. Here are the manufacturer's specs:
http://nexinc.thomasnet.com/item/all-categories/telephone-jacks/tjt-102?&
seo=110 If I can't find one, I'll just hard-wire an 9 pin sub-d port
instead.
Thanks,
Michael H.
________________________________________________________________________________
| From: | "Harold" <kayce33(at)earthlink.net> |
Bravo, Well said
Harold
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
Sent: Thursday, August 24, 2006 7:49 PM
Subject: AeroElectric-List: Paul
>
>
> From: "Paul Messinger" <paulm(at)olypen.com>
> To:
> Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 31 Msgs -
> 08/23/06
> Date: Thu, 24 Aug 2006 12:55:14 -0700
> X-Mailer: Microsoft Outlook Express 6.00.2900.2869
> Sender: owner-aeroelectric-list-server(at)matronics.com
> Reply-To: aeroelectric-list(at)matronics.com
> X-Antivirus: AVG for E-mail 7.1.394 [268.11.3/423]
>
>
> Interesting that this message (from Michael) never arrived at my computer.
>
> And no you are not (building rocket launchers) but if there had been a
> transorb on the aircraft bus (different application than the relay, but
> another one of the Paul vs. Bob arguments (where Paul; says there is a
> transient and Bob: says no because I have never seen one) . . .
>
> Correction: never been able to "capture" a starter induced
> transient in spite of years of specific tests to see if such
> animals exist . . . It wasn't as if I were standing around
> waiting for one to walk by.
>
> . . . where the alternator was damaged by the defectively designed OV
> crow bar, dozens of pilots would not have had to replace the alternator
> and remove the faulty OV device.
>
> You know, it's difficult to "fix" anything when the people
> having problems don't talk to the supplier of the "problem"
> device. Out of about 4 thousand crowbar ov systems now in service
> both OBAM and TC, we've been made aware of and fixed about
> a dozen cases in the past 20 years. Two of the situations
> revealed new data that prompted changes to the design.
>
> I recently posted a pix of a repeatable transient that 100% of the time
> tripped the OV device falsely in my own testing.
>
> Yeah, some fuzzy scope traces with no test setup data
> and no description of the test procedure. No definition
> of the OV device in question. Obviously no contact with
> the original designer in any spirit of curiosity or
> helpful transfer of useful data. How am I or anyone else
> to interpret what you've shared? How do we make use of
> this data to improve on any design?
>
> As you may recall Vans strongly asked builders to REMOVE the OV device as
> it was damaging the alternators with false trips. Told to me by the GM at
> Vans at the time.
>
> This was discussed at length a couple of years ago so there is no need to
> recycle it now.
>
> You have just recycled it yourself, not as a point of
> useful information but as a hammer with an intent to
> injure . . .
>
> My point is on other lists a simple " yes a transorb as Eric suggests is a
> safer way to go and a better solution". No need to get into a thrashing
> session etc. That is as technical as it ever needed to get.
>
> Hmmmm "safer" . . . does it also ward of evil demons and
> bird flu?
>
> That sir is an excellent example of your lack of understanding
> and re-enforces the notion I've long suspected that your
> participation in this discussion has little to do with
> the art and science of building airplanes and a much to
> do with attempts to discredit me. Since you can't win
> with logic and good science, you're now reduced to dragging
> out old canards.
>
> The alternators in question were failed due to load-dump
> effected by b-lead disconnection for one of TWO reasons.
>
> (1) the pilot operated the alternator ON-OFF switch
> while the alternator was under load . . .
>
> -OR-
>
> (2) the ov system tripped for what-ever reason and
> opened the b-lead contactor.
>
> These events would have taken place irrespective of
> the technology behind the OV sensing and control. If
> it had been a simple zener-comparator that was overexcited
> and had dumped the relay, the end result would have been
> the same. You have, and continue to denigrate my work
> with exaggeration and hyperbole and never offered to
> assist in chasing out any bugs, real or imagined.
>
> So the "fix" was to bury heads in the sand and state
> our internally regulated alternators never fail in an
> runaway condition so we'll take that pesky control system
> off.
>
> Vans (like your mythical disgruntled AeroElectric
> Connection customers) never bothered to contact me about
> their problems whereupon they would have been greeted
> with instant cooperative and enthusiastic assistance or
> at least a refund of their money. It's this kind of
> communication and cooperation that makes things BETTER.
> Instead, I hear about the problems from you when you
> wave the news around to re-enforce your obviously
> dismal opinions of me.
>
> Permit me to offer a calm and well considered opinion
> based on years of observations (and dodging your
> mudballs). Hmmmm . . . I wonder if you remember your
> very first phone call to me a long time ago where
> I got a very agitated claim that you'd tried to order
> my book several times and you were tired of being
> ignored. As I recall, I could not find your order(s)
> in the system but shipped you a free book anyhow.
> Now here we are, 12-15 years later and you're still
> accusing me of disrespect, incompetence, dishonorable
> behavior, and any number of evil traits.
>
> A couple of years ago you (and Eric as I recall) went
> off to do some tests. I was delighted with the notion that
> kindred spirits with an interest in promoting OBAM
> aviation had the tools and time to get some badly needed
> data for the purposes of improving upon the best-we-know-
> how-to-do. At least here on the List, nothing came out
> of those tests but ammunition for attacking what had gone
> before . . . and contributed nothing to what could go
> on in the future.
>
> So now we come to it. You are not a teacher sir, you
> explain nothing. Your factual contributions to the list
> have been limited and punctuated with reports (which
> I will now call fabricated) of how unhappy or abused my
> customers are. You've never offered critical review
> of my work based on your own knowledge and understanding.
> You've supported your version of "science" with references
> to the work of others and never with work of your own.
>
> Your demonstrated behavior is the engineering manager's
> worst nightmare: lot's of noise, manufactured discontent
> and and zero work-product that one would be proud to pass
> along to a paying customer. Your conduct here on the List
> is demonstrably contrary to the spirit and intent of those
> who gather here to learn, to be of assistance to others
> and to advance the state of our art and science.
>
> On behalf of my customers to spend their $time$ to exploit
> my $time$, talent and resources . . . and for myself
> now weary of the joust . . . I will ask in what I assure
> you is a very calm and most polite tone to please vacate
> the AeroElectric-List.
>
> Bob . . .
>
>
>
________________________________________________________________________________
| From: | luckymacy(at)comcast.net (lucky) |
| Subject: | Re: Flap switches/relay wiring) |
OK. Off topic but the 727 seems like THE plane to FLY. I know a retired 747 pilot
who said the most fun he ever had, the best plane and routes he ever had were
with 727s. You got to go to a lot of places not serviced by the larger planes
including some class d airports and the plane itself was fun/sporty to fly.
Lots of "interesting" central, south american spots too. But of course the
retirement is based on final salary years so you "have to" move up to 747s if
you can work it out...
-------------- Original message --------------
From: "Olen Goodwin" <ogoodwin(at)comcast.net>
>
> Right you are about the DC8, Bob. I too flew it (about 12 years straight).
> It always seemed an unnatural act to deliberately use reverse in flight....
>
> An exception to what you say about speed brakes not having much effect on
> lift is the Boeing 727, an all around wonderfully capable airplane. The
> speed brakes (flight spoilers) were so effective you could actually lose
> 10,000 feet in less than 10 miles or slow from 350 IAS to 250 in about 4
> miles, not something you'd want to do in a pax airplane (the descent
> anyway), but lots of fun with boxes. Two fine airplanes, either of which I
> wish I was still flying.
>
> Olen Goodwin
> ----- Original Message -----
> From: "OldBob Siegfried"
> To:
> Sent: Thursday, August 24, 2006 4:03 PM
> Subject: Re: Ergonomics (was: AeroElectric-List: Flap switches/relay wiring)
>
>
> >
> >
> >
> > Good Afternoon Kevin,
> >
> > This may have little or no bearing on the subject at
> > hand, but the DC-8 had no speed brake at all!
> >
> > They originally designed one that came out of the
> > fuselage at the wing root. It was totally ineffective
> > and the design was too far along to incorporate a
> > speed brake in the wing structure. They fixed it by
> > making the engine reversers usable in flight. If you
> > wanted a speed brake function in the DC-8, you used
> > inflight thrust reversing.
> >
> > They did employ ground spoilers which were designed to
> > kill as much lift as possible. They were located along
> > the trailing portion of the primary wing structure.
> > Speed brakes that are intended to provide inflight
> > drag tend to be mounted further forward on the wing
> > and be designed so they destroy very little of the
> > lift being developed by the wing. Obviously, there are
> > many variations. Boeing tends to use sections of the
> > trailing edge that also serve as ground spoilers The
> > Caravelle a had a beautiful set of brakes that looked
> > like big brothers of those used on gliders.
> >
> > In general, the inflight speed brakes have a
> > relatively small effect on the lift being produced.
> > The ground spoilers are designed to kill as much of
> > the lift as is possible.
> >
> > No doubt many of our listers can point to exceptions
> > where the functions are mixed even more so than on the
> > Boeings, but the DC-8 had NO speed brakes at all
> > within the aircraft structure. Just the inflight
> > reversing capability. That actually worked quite well.
> > but it sure made a lot of noise and a lot of
> > vibration!
> >
> > Happy Skies,
> >
> > Old (Once upon a time DC-8 captain) Bob
> >
> > --- Kevin Horton wrote:
> >
> >> Horton
> >>
> >> On 24 Aug 2006, at 10:43, Brian Lloyd wrote:
> >>
> >> Lloyd > >> > av(at)lloyd.com>
> >> >
> >> >
> >> > On Aug 24, 2006, at 3:36 AM, Kevin Horton wrote:
> >> >
> >> Horton
> >> >>
> >> >>
> >> >> What happens if there is an accidental deployment
> >> during the
> >> >> landing flare?
> >> >
> >> > Remember, this is a speed brake, not a spoiler. It
> >> increases drag
> >> > but has very little effect on lift. The effect of
> >> a speed brake
> >> > decreases as IAS decreases. The airplane slows
> >> down but not as much
> >> > as at Vne. I doubt that speed brake would really
> >> have any
> >> > significant effect in the landing flare.
> >>
> >> Sorry, I thought that the Glasair installation was
> >> likely on the
> >> wing, and its deployment would reduce the lift, as
> >> well as produce
> >> extra drag. I was wondering if the loss of lift at
> >> low speed at a
> >> critical flight phase could be a problem.
> >>
> >> Air Canada had a fatal accident with a DC-8 at
> >> Toronto many, many
> >> years ago. There was a screw up in the flight deck,
> >> which resulted
> >> in the ground spoilers being deployed at about 60 ft
> >> AGL. No survivors.
> >>
> >>
> > http://aviation-safety.net/database/record.php?id=19700705-0
> >>
> >> If the Glasair speedbrakes are not on the wing, then
> >> my original
> >> question was not relevant.
> >>
> >> Kevin Horton RV-8 (finishing kit)
> >> Ottawa, Canada
> >> http://www.kilohotel.com/rv8
> >>
> >>
> >>
> >> browse
> >> Subscriptions page,
> >> FAQ,
> >> http://www.matronics.com/Navigator?AeroElectric-List
> >>
> >> Web Forums!
> >>
> >>
> >> Admin.
> >>
> >>
> >>
> >>
> >>
> >
> >
> >
> >
> >
>
>
>
>
>
OK. Off topic but the 727 seems like THE plane to FLY. I know a
retired 747 pilot who said the most fun he ever had, the best plane and
routes he ever had were with 727s. You got to go to a lot of places not
serviced by the larger planes including some class d airports and the plane itself
was fun/sporty to fly. Lots of "interesting" central, south american
spots too. But of course the retirement is based on final salary years
so you "have to" move up to 747s if you can work it out...
> --> AeroElectric-List message
posted by: "Olen Goodwin"
>
> Right you are
about the DC8, Bob. I too flew it (about 12 years straight).
> It always
seemed an unnatural act to deliberately use reverse in flight....
>
> An exception to what you say about speed brakes not having much effect
on
> lift is the Boeing 727, an all around wonderfully capable airplane.
The
> speed brakes (flight spoilers) were so effective you could actually
lose
> 10,000 feet in less than 10 miles or slow from 350 IAS to
250 in about 4
> miles, not something you'd want to do in a pax airplane
(the descent
> anyway), but lots of fun with boxes. Two fine airplanes,
either of which I
> wish I was still flyi
ng. >
> Olen Goodwin
> ----- Original Message -----
> From:
"OldBob Siegfried"
> To:
>
Sent: Thursday, August 24, 2006 4:03 PM
> Subject:
Re: Ergonomics (was: AeroElectric-List: Flap switches/relay wiring)
>
>
> > --> AeroElectric-List message posted by: OldBob Siegfried
> >
> >
> >
>
> Good Afternoon Kevin,
> >
> > This may have little
or no bearing on the subject at
> > hand, but the DC-8 had no speed
brake at all!
> >
> > They originally designed one that
came out of the
> > fuselage at the wing root. It was totally ineffective
> > and the design was too far along to incorporate a
>
> speed brake in the wing structure. They fixed it by
> > making
the engine reversers usable in flight. If you
&
gt; &g
t; wanted a speed brake function in the DC-8, you used
> > inflight thrust
reversing.
> >
> > They did employ ground spoilers which
were designed to
> > kill as much lift as possible. They were located
along
> > the trailing portion of the primary wing structure.
> > Speed brakes that are intended to provide inflight
> >
drag tend to be mounted further forward on the wing
> > and be designed
so they destroy very little of the
> > lift being developed by
the wing. Obviously, there are
> > many variations. Boeing tends to
use sections of the
> > trailing edge that also serve as ground spoilers
The
> > Caravelle a had a beautiful set of brakes that looked
> > like big brothers of those used on gliders.
> >
>
> In general, the inflight speed brakes have a
> > relatively
small effect on the lift being produced.
> >
; The
ground spoilers are designed to kill as much of
> > the lift as is possible.
> >
> > No doubt many of our listers can point to
exceptions
> > where the functions are mixed even more so than on the
> > Boeings, but the DC-8 had NO speed brakes at all
> >
within the aircraft structure. Just the inflight
> > reversing capability.
That actually worked quite well.
> > but it sure made a lot
of noise and a lot of
> > vibration!
> >
> > Happy
Skies,
> >
> > Old (Once upon a time DC-8 captain) Bob
> >
> > --- Kevin Horton wrote:
>
>
> >> --> AeroElectric-List message posted by: Kevin
> >> Horton
> >>
> >>
On 24 Aug 2006, at 10:43, Brian Lloyd wrote:
> >>
> >>
> --> AeroElectric-List message posted
by: Br
ian
> >> Lloyd > >> > av(at)lloyd.com>
>
>> >
> >> >
> >> > On Aug 24, 2006,
at 3:36 AM, Kevin Horton wrote:
> >> >
> >>
>> --> AeroElectric-List message posted by: Kevin
> >> Horton
> >> >>
> >> >>
> >> >> What happens if there is an accidental deployment
> >> during the
> >> >> landing flare?
>
>> >
> >> > Remember, this is a speed brake, not
a spoiler. It
> >> increases drag
> >> > but has
very little effect on lift. The effect of
> >> a speed brake
>
>> > decreases as IAS decreases. The airplane slows
> >>
down but not as much
> >> > as at Vne. I doubt that speed
brake would really
> >> have any
> &
gt;> > significant effect in the landing flare.
> >>
> >> Sorry, I thought that the Glasair installation was
> >> likely on the
> >> wing, and its deployment would reduce the lift, as
> >> well as produce
> >> extra drag. I was wondering if the loss of lift at
> >> low speed at a
> >> critical flight phase could be a problem.
> >>
> >> Air Canada had a fatal accident with a DC-8 at
> >> Toronto many, many
> >> years ago. There was a screw up in the flight deck,
> >> which resulted
> >> in the ground spoilers being deployed at about 60 ft
> >> AGL. No survivors.
> >>
> >>
> > http://aviation-safety.net/database/record.php?id=19700705-0
> >>
> >> If the Glasair speedbrakes are not on the wing, then
> >> my
origin
nload,
________________________________________________________________________________
| From: | Richard Dudley <rhdudley1(at)bellsouth.net> |
Hey Bob,
Well said - again. However, the receiver has a tin ear
You have my vote!!!!!!
RHDudley
Robert L. Nuckolls, III wrote:
>
>
> From: "Paul Messinger" <paulm(at)olypen.com>
> To:
> Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 31 Msgs
> - 08/23/06
> Date: Thu, 24 Aug 2006 12:55:14 -0700
> X-Mailer: Microsoft Outlook Express 6.00.2900.2869
> Sender: owner-aeroelectric-list-server(at)matronics.com
> Reply-To: aeroelectric-list(at)matronics.com
> X-Antivirus: AVG for E-mail 7.1.394 [268.11.3/423]
>
>
> Interesting that this message (from Michael) never arrived at my
> computer.
>
> And no you are not (building rocket launchers) but if there had been a
> transorb on the aircraft bus (different application than the relay,
> but another one of the Paul vs. Bob arguments (where Paul; says there
> is a transient and Bob: says no because I have never seen one) . . .
>
> Correction: never been able to "capture" a starter induced
> transient in spite of years of specific tests to see if such
> animals exist . . . It wasn't as if I were standing around
> waiting for one to walk by.
>
> . . . where the alternator was damaged by the defectively designed OV
> crow bar, dozens of pilots would not have had to replace the
> alternator and remove the faulty OV device.
>
> You know, it's difficult to "fix" anything when the people
> having problems don't talk to the supplier of the "problem"
> device. Out of about 4 thousand crowbar ov systems now in service
> both OBAM and TC, we've been made aware of and fixed about
> a dozen cases in the past 20 years. Two of the situations
> revealed new data that prompted changes to the design.
>
> I recently posted a pix of a repeatable transient that 100% of the
> time tripped the OV device falsely in my own testing.
>
> Yeah, some fuzzy scope traces with no test setup data
> and no description of the test procedure. No definition
> of the OV device in question. Obviously no contact with
> the original designer in any spirit of curiosity or
> helpful transfer of useful data. How am I or anyone else
> to interpret what you've shared? How do we make use of
> this data to improve on any design?
>
> As you may recall Vans strongly asked builders to REMOVE the OV device
> as it was damaging the alternators with false trips. Told to me by the
> GM at Vans at the time.
>
> This was discussed at length a couple of years ago so there is no need
> to recycle it now.
>
> You have just recycled it yourself, not as a point of
> useful information but as a hammer with an intent to
> injure . . .
>
> My point is on other lists a simple " yes a transorb as Eric suggests
> is a safer way to go and a better solution". No need to get into a
> thrashing session etc. That is as technical as it ever needed to get.
>
> Hmmmm "safer" . . . does it also ward of evil demons and
> bird flu?
>
> That sir is an excellent example of your lack of understanding
> and re-enforces the notion I've long suspected that your
> participation in this discussion has little to do with
> the art and science of building airplanes and a much to
> do with attempts to discredit me. Since you can't win
> with logic and good science, you're now reduced to dragging
> out old canards.
>
> The alternators in question were failed due to load-dump
> effected by b-lead disconnection for one of TWO reasons.
>
> (1) the pilot operated the alternator ON-OFF switch
> while the alternator was under load . . .
>
> -OR-
>
> (2) the ov system tripped for what-ever reason and
> opened the b-lead contactor.
>
> These events would have taken place irrespective of
> the technology behind the OV sensing and control. If
> it had been a simple zener-comparator that was overexcited
> and had dumped the relay, the end result would have been
> the same. You have, and continue to denigrate my work
> with exaggeration and hyperbole and never offered to
> assist in chasing out any bugs, real or imagined.
>
> So the "fix" was to bury heads in the sand and state
> our internally regulated alternators never fail in an
> runaway condition so we'll take that pesky control system
> off.
>
> Vans (like your mythical disgruntled AeroElectric
> Connection customers) never bothered to contact me about
> their problems whereupon they would have been greeted
> with instant cooperative and enthusiastic assistance or
> at least a refund of their money. It's this kind of
> communication and cooperation that makes things BETTER.
> Instead, I hear about the problems from you when you
> wave the news around to re-enforce your obviously
> dismal opinions of me.
>
> Permit me to offer a calm and well considered opinion
> based on years of observations (and dodging your
> mudballs). Hmmmm . . . I wonder if you remember your
> very first phone call to me a long time ago where
> I got a very agitated claim that you'd tried to order
> my book several times and you were tired of being
> ignored. As I recall, I could not find your order(s)
> in the system but shipped you a free book anyhow.
> Now here we are, 12-15 years later and you're still
> accusing me of disrespect, incompetence, dishonorable
> behavior, and any number of evil traits.
>
> A couple of years ago you (and Eric as I recall) went
> off to do some tests. I was delighted with the notion that
> kindred spirits with an interest in promoting OBAM
> aviation had the tools and time to get some badly needed
> data for the purposes of improving upon the best-we-know-
> how-to-do. At least here on the List, nothing came out
> of those tests but ammunition for attacking what had gone
> before . . . and contributed nothing to what could go
> on in the future.
>
> So now we come to it. You are not a teacher sir, you
> explain nothing. Your factual contributions to the list
> have been limited and punctuated with reports (which
> I will now call fabricated) of how unhappy or abused my
> customers are. You've never offered critical review
> of my work based on your own knowledge and understanding.
> You've supported your version of "science" with references
> to the work of others and never with work of your own.
>
> Your demonstrated behavior is the engineering manager's
> worst nightmare: lot's of noise, manufactured discontent
> and and zero work-product that one would be proud to pass
> along to a paying customer. Your conduct here on the List
> is demonstrably contrary to the spirit and intent of those
> who gather here to learn, to be of assistance to others
> and to advance the state of our art and science.
>
> On behalf of my customers to spend their $time$ to exploit
> my $time$, talent and resources . . . and for myself
> now weary of the joust . . . I will ask in what I assure
> you is a very calm and most polite tone to please vacate
> the AeroElectric-List.
>
> Bob . . .
>
>
>
________________________________________________________________________________
| From: | "Paul McAllister" <paul.mcallister(at)qia.net> |
Bob,
We are kindred sprits in one aspect.....we calmly deliver facts in a
pragmatic manner.
It amazing how some people react so emotionally to this.
Regards,
Paul McAllister
N378PJ
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Robert
L. Nuckolls, III
Sent: Thursday, August 24, 2006 6:49 PM
Subject: PROBABLE SPAM> AeroElectric-List: Paul
From: "Paul Messinger" <paulm(at)olypen.com>
Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 31 Msgs -
08/23/06
Date: Thu, 24 Aug 2006 12:55:14 -0700
Sender: owner-aeroelectric-list-server(at)matronics.com
X-Antivirus: AVG for E-mail 7.1.394 [268.11.3/423]
Interesting that this message (from Michael) never arrived at my computer.
And no you are not (building rocket launchers) but if there had been a
transorb on the aircraft bus (different application than the relay, but
another one of the Paul vs. Bob arguments (where Paul; says there is a
transient and Bob: says no because I have never seen one) . . .
Correction: never been able to "capture" a starter induced
transient in spite of years of specific tests to see if such
animals exist . . . It wasn't as if I were standing around
waiting for one to walk by.
. . . where the alternator was damaged by the defectively designed OV
crow bar, dozens of pilots would not have had to replace the alternator and
remove the faulty OV device.
You know, it's difficult to "fix" anything when the people
having problems don't talk to the supplier of the "problem"
device. Out of about 4 thousand crowbar ov systems now in service
both OBAM and TC, we've been made aware of and fixed about
a dozen cases in the past 20 years. Two of the situations
revealed new data that prompted changes to the design.
I recently posted a pix of a repeatable transient that 100% of the time
tripped the OV device falsely in my own testing.
Yeah, some fuzzy scope traces with no test setup data
and no description of the test procedure. No definition
of the OV device in question. Obviously no contact with
the original designer in any spirit of curiosity or
helpful transfer of useful data. How am I or anyone else
to interpret what you've shared? How do we make use of
this data to improve on any design?
As you may recall Vans strongly asked builders to REMOVE the OV device as
it was damaging the alternators with false trips. Told to me by the GM at
Vans at the time.
This was discussed at length a couple of years ago so there is no need to
recycle it now.
You have just recycled it yourself, not as a point of
useful information but as a hammer with an intent to
injure . . .
My point is on other lists a simple " yes a transorb as Eric suggests is a
safer way to go and a better solution". No need to get into a thrashing
session etc. That is as technical as it ever needed to get.
Hmmmm "safer" . . . does it also ward of evil demons and
bird flu?
That sir is an excellent example of your lack of understanding
and re-enforces the notion I've long suspected that your
participation in this discussion has little to do with
the art and science of building airplanes and a much to
do with attempts to discredit me. Since you can't win
with logic and good science, you're now reduced to dragging
out old canards.
The alternators in question were failed due to load-dump
effected by b-lead disconnection for one of TWO reasons.
(1) the pilot operated the alternator ON-OFF switch
while the alternator was under load . . .
-OR-
(2) the ov system tripped for what-ever reason and
opened the b-lead contactor.
These events would have taken place irrespective of
the technology behind the OV sensing and control. If
it had been a simple zener-comparator that was overexcited
and had dumped the relay, the end result would have been
the same. You have, and continue to denigrate my work
with exaggeration and hyperbole and never offered to
assist in chasing out any bugs, real or imagined.
So the "fix" was to bury heads in the sand and state
our internally regulated alternators never fail in an
runaway condition so we'll take that pesky control system
off.
Vans (like your mythical disgruntled AeroElectric
Connection customers) never bothered to contact me about
their problems whereupon they would have been greeted
with instant cooperative and enthusiastic assistance or
at least a refund of their money. It's this kind of
communication and cooperation that makes things BETTER.
Instead, I hear about the problems from you when you
wave the news around to re-enforce your obviously
dismal opinions of me.
Permit me to offer a calm and well considered opinion
based on years of observations (and dodging your
mudballs). Hmmmm . . . I wonder if you remember your
very first phone call to me a long time ago where
I got a very agitated claim that you'd tried to order
my book several times and you were tired of being
ignored. As I recall, I could not find your order(s)
in the system but shipped you a free book anyhow.
Now here we are, 12-15 years later and you're still
accusing me of disrespect, incompetence, dishonorable
behavior, and any number of evil traits.
A couple of years ago you (and Eric as I recall) went
off to do some tests. I was delighted with the notion that
kindred spirits with an interest in promoting OBAM
aviation had the tools and time to get some badly needed
data for the purposes of improving upon the best-we-know-
how-to-do. At least here on the List, nothing came out
of those tests but ammunition for attacking what had gone
before . . . and contributed nothing to what could go
on in the future.
So now we come to it. You are not a teacher sir, you
explain nothing. Your factual contributions to the list
have been limited and punctuated with reports (which
I will now call fabricated) of how unhappy or abused my
customers are. You've never offered critical review
of my work based on your own knowledge and understanding.
You've supported your version of "science" with references
to the work of others and never with work of your own.
Your demonstrated behavior is the engineering manager's
worst nightmare: lot's of noise, manufactured discontent
and and zero work-product that one would be proud to pass
along to a paying customer. Your conduct here on the List
is demonstrably contrary to the spirit and intent of those
who gather here to learn, to be of assistance to others
and to advance the state of our art and science.
On behalf of my customers to spend their $time$ to exploit
my $time$, talent and resources . . . and for myself
now weary of the joust . . . I will ask in what I assure
you is a very calm and most polite tone to please vacate
the AeroElectric-List.
Bob . . .
________________________________________________________________________________
Bob,
I have your flap schematics in the pdf format. Would you point me to the
ACAD files?
Thanks
Peter Laurence
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
It was not a starter but a simple relay 10 amp on off load but I am sorry I
have pulled your chain.
By By
Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr(at)cox.net>
________________________________________________________________________________
| Subject: | Re: Nexus M9177/4-1 |
Hi Michael,
I did a froogle search on TJT-102 and found it at skygeek
http://stylespilotshop.stores.yahoo.net/jb-11v.html for $18.95.
I don't know anything about the company.
Hope this helps,
Bob W.
"Michael Hinchcliff" wrote:
> Can somebody tell me where I can buy a single Nexus TJT-102 also known as a M9177/4-1 female adapter? These are used by Allied-Signal/Honeywell panel-mounted GPS products as a data loader port. I have the PC data cable with the male end, but I need the female end to mount in the instrument panel. I contacted the manufacturer and they won't sell me less than 50 at a time. Their direct distributors are the same. Here are the manufacturer's specs: http://nexinc.thomasnet.com/item/all-categories/telephone-jacks/tjt-102?&seo=110 If I can't find one, I'll just hard-wire an 9 pin sub-d port instead.
>
>
>
> Thanks,
>
> Michael H.
>
--
http://www.bob-white.com
N93BD - Rotary Powered BD-4 (first engine start 1/7/06)
Custom Cables for your rotary installation -
http://www.roblinphoto.com/shop/
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
><PLaurence@the-beach.net>
>
>
>Bob,
>I have your flap schematics in the pdf format. Would you point me to the
>ACAD files?
Try:
http://www.aeroelectric.com/PPS/Flight/Flaps/Flaps.dwg
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: Your book etc. |
>Dear Bob,
> After reading your book I am wanting to redo my aircraft wiring. I
> have re read much of your book and have some questions:
>
>
> 1, What is your main reason for using the heavy duty contactor
> ? It does require some current to hold it down and a switch uses a spring.
> 2, I also use a knife switch in the negative side of the battery
> with a mechanical link to the panel. It seems to work ok and makes it
> easy to take the battery out of the circuit which I like. It will have
> some resistance but not much. It is one used in cars and trucks and is
> available from several sources. What would you say about this?
Any means you might devise to serve as a battery master
disconnect is certainly possible and even encouraged in
the OBAM aircraft community. The contactor is convenient
and works in about any situation irrespective of the aircraft
or battery location and it's easy.
Many production aircraft in times past had manuall operated
switches of one kind or another. I took lessons in a Piper
Tri-Pacer about 45 years ago that had manual battery switch
and manual starter switches.
> 3. I have replaced the Rotax engine with a Corvair engine made by
> William Wynne which uses two coils and a dual set of breaker points for
> almost a dual ignition system, but uses only one set of plugs. I have it
> running now but would like to do a rewire with an E buss and another
> battery. To justify the added weight I may have to lose some weight
> myself but I like the idea.
I've met Mr. Wynne and read his publications. He's done
some impressive work with the Corvair conversions. Why
do you think you need dual batteries?
> 4, Does B&C Electronics sell kits?
Not that I know of.
> 5. Thanks for writing a good book (may I expect some more pages?)
Sure. Keep an eye on the What's New? section of our website.
You buy the book only one time and you can download future
updates from the website as they are published.
Bob . . .
---------------------------------------------------------
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
---------------------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
>Removed U114, jumpered 2 & 3 together. Now when I apply power nothing is
>amplified. That is, in stereo configuration you could hear music without
>power but it was much louder with power. Now in the "mono" configuration
>with the above changes, no difference can be heard in loudness when power
>is applied.
>
Are you sure you've wired it right? Which side of the board has
the connector on it? Note there are two pinout configurations
depending on how the connector is mounted. See latest instruction
manual for an amplification of this situation. It was recently
updated and posted at:
http://www.aeroelectric.com/Catalog/AEC/9009/9009-700H.pdf
Check out note 14 on Page 2
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Off to California |
I had hoped to get to many more messages before we
left but I'm out of time and need to pack the bags.
Dr. Dee and I are headed to Auburn (Sacremento), CA
for a weekend of "airplanespeak" and other good conversations.
Hope to meet some of you there in person.
Be back on Monday.
Bob . . .
---------------------------------------------------------
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
---------------------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: Problem with Power Sources |
>I just finished my RV-4 and used Bob's Z-11 plan with a Battery Bus, Main
>Bus and E Bus. Somehow I have them isolated so that the main works of the
>Master, the E bus switch lights the avionics, but I can't get the Main bus
>to feed the E Bus without turning it on.
>
>At first I thought I had miswired and blown the Diode, but I replaced that
>and still have the same squawk. The plane's electrical systems all work,
>but I wonder what I did wrong. I also wonder if I'm placing the whole
>system in jeopardy by using both switches to hot up everything. Appreciate
>any troubleshooting ideas.
>Ron
Did you get this figured out okay?
Bob . . .
________________________________________________________________________________
| From: | "Olen Goodwin" <ogoodwin(at)comcast.net> |
| Subject: | Re: Flap switches/relay wiring) |
Too bad the old airplanes that required "piloting" are all being
retired. I enjoyed them, and I think lots of the guys that liked flying
for it's own sake did. Interesting what you said about the 747...that's
where I'm headed in October. Bittersweet indeed.
Apologies for the off topic.
Olen
----- Original Message -----
From: lucky
To: aeroelectric-list(at)matronics.com
Sent: Thursday, August 24, 2006 6:37 PM
Subject: Re: Ergonomics (was: AeroElectric-List: Flap switches/relay
wiring)
OK. Off topic but the 727 seems like THE plane to FLY. I know a
retired 747 pilot who said the most fun he ever had, the best plane and
routes he ever had were with 727s. You got to go to a lot of places not
serviced by the larger planes including some class d airports and the
plane itself was fun/sporty to fly. Lots of "interesting" central, south
american spots too. But of course the retirement is based on final
salary years so you "have to" move up to 747s if you can work it out...
________________________________________________________________________________
| From: | "6440 Auto Parts" <sales(at)6440autoparts.com> |
| Subject: | Re: Garmin GNS 530 Installation Manual |
Garmin no longer shows they're install manual's from that site
----- Original Message -----
From: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
Sent: Thursday, August 24, 2006 5:29 PM
Subject: Re: AeroElectric-List: Garmin GNS 530 Installation Manual
> <Gilles.Thesee@ac-grenoble.fr>
>
>
>>
>> Does anyone know where I can find a .pdf of a Garmin GNS 530 Installation
>> Manual?
>>
>> Thanks!
>>
> Have you tried
>
> http://contrails.free.fr/gps_manuels.php ?
>
> Regards,
> Gilles Thesee
> Grenoble, France
> http://contrails.free.fr
>
>
>
________________________________________________________________________________
| From: | "DonVS" <dsvs(at)comcast.net> |
| Subject: | Garmin GNS 530 Installation Manual |
Try Stark Avionics. They have most of them on PDF and may e-mail you one
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of 6440
Auto Parts
Sent: Thursday, August 24, 2006 8:55 PM
Subject: Re: AeroElectric-List: Garmin GNS 530 Installation Manual
Garmin no longer shows they're install manual's from that site
----- Original Message -----
From: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
Sent: Thursday, August 24, 2006 5:29 PM
Subject: Re: AeroElectric-List: Garmin GNS 530 Installation Manual
> <Gilles.Thesee@ac-grenoble.fr>
>
>
>>
>> Does anyone know where I can find a .pdf of a Garmin GNS 530 Installation
>> Manual?
>>
>> Thanks!
>>
> Have you tried
>
> http://contrails.free.fr/gps_manuels.php ?
>
> Regards,
> Gilles Thesee
> Grenoble, France
> http://contrails.free.fr
>
>
________________________________________________________________________________
| Subject: | Re: Garmin GNS 530 Installation Manual |
> >
>
> Garmin no longer shows they're install manual's from that site
>
>>>
>> Have you tried
>>
>> http://contrails.free.fr/gps_manuels.php ?
There are about one dozen installation manuals, except the 530
installation manual, I'm afraid.
Have you tried Ebay ?
http://cgi.ebay.com/ebaymotors/Garmin-Avionics-Install-Manuals-CD-New-Complete-Set_W0QQitemZ290020993542QQihZ019QQcategoryZ26436QQcmdZViewItem
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
| From: | <gmcjetpilot(at)yahoo.com> |
| Subject: | Flap switches/relay) |
Speed Brakes vs. Spoilers. If they are wind spoilers the kill lift in a big way
and would be more of an issue than a body mounted speed brake.
I put the flap switch on my RV-4 stick grip (MAC grip). To reduce the chance
of accidental deployment I cut the mini-toggle switch down very very short, so
to operate, you put your thumb on top to move it. It was also spring loaded to
up.
The MAC grip standard toggle switch lever, although small still got caught on
things and caused accidental deployment. After cut down you still had to be careful
and not rest things on top of the stick. The trim buttons where there and
the PTT on the front.
I WILL NOT DO ALL THE BUTTONS ON THE GRIP ON MY NEW PROJECT.
My new project, RV-7 has the flap switch (and trim) on the panel near the throttle/prop/mixture.
The wiring is way simple and the heavy duty flap switch can
handle the flap motor with out troublesome relays.
George RV-4, RV-7
>Subject: RE: Ergonomics (was: AeroElectric-List: Flap switches/relay
wiring)
>From: "Matt Prather" <mprather(at)spro.net>
>
>Speed brakes are usually very small drag producers that provide energy
>control while at high indicated airspeeds. Once slowed to a low
>airspeed, speed brakes represent a very small portion of airframe drag.
>Sometimes, takeoff performance isn't even particularly degraded with the brakes
>extended.
>
>Regards, Matt-
---------------------------------
________________________________________________________________________________
| From: | Dave <dave(at)abrahamson.net> |
| Subject: | Re: Garmin GNS 530 Installation Manual |
You may have the following but JIC... I cannot find the installation
manual, but I know for sure that Stark avionics has it cuz I called
with a 430 question and Tony accidentally looked at the 530 manual
first. Don't know whether he has paper copy or online version.
<http://www.garmin.com/manuals/%7Binsert>http://www.garmin.com/manuals/GNS530_PilotsGuide.pdf
GNS530_ApprovedFlightManualSupplement.PDF
GNS530_QuickReferenceGuide.pdf
GNS530_LBAApprovedFlightManualSupplement.pdf
________________________________________________________________________________
| From: | "Olen Goodwin" <ogoodwin(at)comcast.net> |
| Subject: | Re: Old Man's Musings |
Bob, I'll be going into the 200/300. Probably a good thing, since I
won't have to learn the glass and automation of the 400.
Olen
________________________________________________________________________________
| Subject: | Paul and other thoughts |
| From: | "Crapse, Richard W (Rick), WWCS" <rwcrapse(at)att.com> |
I read the thread with Paul and I have to laugh. It reminds me of
another situation with Dave Atkins and redrives for Rotary engines. He
uses a spur gear setup because "planetary gears won't hold up". Tracy
Crook took the engineers way and did a failure analysis on the same
redrive design. Funny , they came to different conclusions. Lack of a
thrust bearing and incorrect lubrication paths led to the Ross redrive
killing itself, not the gear design is what Tracy found. This thing with
Paul and Bob smacks of the same vein.
I had the opportunity to read Bob's book, attend his seminar, and attend
Greg Richter's seminar at OshKosh. Now here is another holy war that
goes on. Bob and Greg will disagree with me on this, but I found it
fascinating that they are aruging the same point on wiring aircraft and
ground paths from two separate view points. They call it different
things, but the gist is there. Greg prefers the solder and heat shrink
tube, Bob prefers the Fast-On connectors. Both want a gas tight,
electrically sound connection. Both talk about shielding and how to do
it correctly. Bob likes fuses, Greg likes polyfuses. Differing thoughts,
but both have their valid points. As someone who deals with the mighty
invisible heart of radio (vacuum tubes) and who deals with SMT, TTL,
CMOS devices, I can say that in SOME applications, one version of
technology is superior to another, but not universally. For example,
vacuum tube diodes are far quieter than their counterpart solid state
brothers. However, does it justify using the vacuum tube diode in modern
radio gear? If we are talking about a Hi-Fi amp or stereo, I personally
like the sound of the older tube types that the solid state does not
match. But then again, when dealing with aircraft radios and modern HT's
versus battery life versus vibration, the solid state works just fine,
thank-you very much. In sand storm conditions? Give me the vaccum tube
finals, they could care less about the static charges, makes them glow
brighter. And before you argue that they are dead, the next gen is
coming out a nano tubes with cold cathodes for satellites. Now isn't
that a surprise?
I try to learn from everybody, but I always have to understand where
they are coming from first and why. Much better education that way.
Rick
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Paul and other thoughts |
On Aug 25, 2006, at 7:02 AM, Crapse, Richard W (Rick), WWCS wrote:
> I had the opportunity to read Bob's book, attend his seminar, and
> attend
> Greg Richter's seminar at OshKosh. Now here is another holy war that
> goes on. Bob and Greg will disagree with me on this, but I found it
> fascinating that they are aruging the same point on wiring aircraft
> and
> ground paths from two separate view points. They call it different
> things, but the gist is there.
When we were creating the technology that became the Internet, we ran
into the same problem. Brilliant people would argue their points
vociferously and nearly come to blows. It would usually take an
equally-bright third party to determine that they were saying the
same thing but using different words. The difference was usually in
the inconsequential details. We even came up with a name for the
phenomenon: agreeing violently.
So I just shrugged and decided that Bob and Greg, and Bob and Paul
were just agreeing violently ... for the most part.
But when things like this happen I usually look for whoever has the
simplest solution.
I am going to go meet Bob tomorrow at Auburn. I have been
corresponding with him for ten years and have never met him face-to-
face. It should be interesting.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| Subject: | Re: Marketing research question Annunciated Parameters |
| From: | "Condrey, Bob (US SSA)" <bob.condrey(at)baesystems.com> |
Has anything ever come of the annunciator panel?
Bob
RV-10 #40105
________________________________________________________________________________
| From: | "James Redmon" <james(at)berkut13.com> |
| Subject: | Noise filter noise |
Hi all,
I'm wondering if someone could educate me a little on something I
encountered while trying to eliminate electrical noise coming from an
autopilot servo. The story goes like this:
I recently installed a new autopilot servo in my Berkut (all composite). It
worked perfectly, but for some reason, the servo makes a loud squealing
noise in the intercom audio when it's activated. I did all the usual
things - changed ground points, increased grounding, double checked
shielding on cables, un-bundled wires, ferrite beads on the cables, etc.
The only thing that really worked was to power the servo from a separate
battery - indicating electrical propagation, not RF. I spoke with the
manufacturer, and they did mention that there was a 2.5KHz PWM signal that
is used to control the servo, and that the "noise" I hear is likely that.
So, on to trying to isolate the servo from everything else...right.
I first tried (at the manufacturer's request) a pair of capacitors (.1uf and
4700uf) in parallel, grounded off the servo power lead itself. This did
slightly dampen the noise, but certainly not enough. So, I also went out
and purchased a common 10-amp car audio power filter - just like those sold
by Radio Shack and documented by Bob on his site - 2 caps with a choke coil
potted in a case although I can not see the ratings on the caps. I placed
the filter in an orientation that isolated the power source from the servo,
instead of servo from power source as IT was the verified source of the
noise.
The good news is, that filter eliminated about 99% of the noise - and that's
good to go. I have not yet done extensive tests to see if the AP now
operates properly in flight with the filter in-line (possible I/O errors,
proper servo feedback, etc)...that's coming soon. But, I want to explore
the "weirdness" first.
Now, the weird (to me anyway) part is that the filter itself now audibly
"sings" with the same frequency that I had heard before on the intercom. I
mean, it literally makes the noise like a speaker would. Is this normal?
What would be causing that? Is this symptomatic of some additional problem
that might effect servo operation? Something else I should do or try?
All information and education is welcome...but remember, I'm not an EE. ;-)
Eager to learn,
James Redmon
Berkut #013 N97TX
http://www.berkut13.com
By the way, this is not a common situation as the manufacturer has not seen
this type of issue before...although they are doing everything they can to
get this under control - under warranty, to their credit! I have no issues
with the way they are handling this..so please don't pester me about that
part.
________________________________________________________________________________
| Subject: | Strobe /beacon question. |
| From: | "rlnelson5" <rlnelson-5(at)peoplepc.com> |
Hello, I have a Whalen power pack that will drive 4 units. I have aquired 2 wing
tip, 1 tail and 1 red beacon. I would like some feedback as how to wire this
up. I could just wire it as a 4 way strobe on 1 switch. I was thinking that it
might be better to wire this so that the beacon goes on first and then adding
the rest of the strobes with another switch or perhaps a 2-10 type switch. I
m not sure how to do that since the power pack will have to be powered for anything
to work. I was thinking it would be good to shut off the strobes in fog/clouds
but still leave the red beacon going. Is this a good idea or just more
work then needed?
Thanks
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=57330#57330
________________________________________________________________________________
| From: | Ron Patterson <scc_ron(at)yahoo.com> |
| Subject: | Problems with High EGT readings |
Hey all,
I've just begun to have 1450+ EGT readings on all cylinders, while the CHT's remain
below 390 degrees. No attempt to richen things up (carb heat for example)
improves things. I took off the cowl and see no exterior signs of trouble, removed
spark plugs and they are nice and tan and even wet from running too rich.
I tried a brief flight and all was normal, then on the next long leg they did
it again. I recycled the Grand Rapids EIS and then only one cylinder persisted
in giving me this reading. Am I right to assume it is an indicator/gauge issue
or am I missing something more ominous?
Thanks in advance for your ideas.
Ron
RV-4 N8ZD
________________________________________________________________________________
| From: | "William Gill" <wgill10(at)comcast.net> |
| Subject: | Princeton capacitance converters -- RV-7 |
Hello All,
I had planned to mount these capacitance converters on the sub-panel,
but the shielded wire is slightly too short if routed where it will
remain out of view. So, the current plan is to mount them between the
seat ribs. Has anyone else mounted them between the seat ribs?
Pros/Cons/any pictures? Thanks in advance for your input.
Have a great weekend,
Bill
RV-7 wiring
Lee's Summit, MO.
________________________________________________________________________________
| From: | FLYaDIVE(at)aol.com |
| Subject: | Re: Strobe /beacon question. |
In a message dated 8/25/06 3:40:31 PM Eastern Daylight Time,
rlnelson-5(at)peoplepc.com writes:
> Hello, I have a Whalen power pack that will drive 4 units. I have aquired 2
> wing tip, 1 tail and 1 red beacon. I would like some feedback as how to
wire
> this up. I could just wire it as a 4 way strobe on 1 switch. I was thinking
> that it might be better to wire this so that the beacon goes on first and
> then adding the rest of the strobes with another switch or perhaps a 2-10
> type switch. I m not sure how to do that since the power pack will have to
be
> powered for anything to work. I was thinking it would be good to shut off
the
> strobes in fog/clouds but still leave the red beacon going. Is this a good
> idea or just more work then needed?
> Thanks
=======================
Nelson:
>From your explanation all four items are flash tubes for the strobe power
supply. If that is the case then the only proper way to wire them is with one
SPST switch to turn on and off the strobe power supply. either ALL is ON or ALL
is OFF.
You do NOT turn the flash tubes on / off you turn the power supply On & Off.
Barry
"Chop'd Liver"
"Show them the first time, correct them the second time, kick them the third
time."
Yamashiada
________________________________________________________________________________
| From: | FLYaDIVE(at)aol.com |
| Subject: | Re: Noise filter noise |
In a message dated 8/25/06 2:26:09 PM Eastern Daylight Time,
james(at)berkut13.com writes:
> Hi all,
>
> I'm wondering if someone could educate me a little on something I
> encountered while trying to eliminate electrical noise coming from an
> autopilot servo. The story goes like this:
>
> I recently installed a new autopilot servo in my Berkut (all composite).
It
> worked perfectly, but for some reason, the servo makes a loud squealing
> noise in the intercom audio when it's activated.
[Barry] When what is activated, the intercom or the servo?
> I did all the usual
> things - changed ground points, increased grounding, double checked
> shielding on cables, un-bundled wires, ferrite beads on the cables, etc.
> The only thing that really worked was to power the servo from a separate
> battery - indicating electrical propagation, not RF. I spoke with the
> manufacturer, and they did mention that there was a 2.5KHz PWM signal that
> is used to control the servo, and that the "noise" I hear is likely that.
> So, on to trying to isolate the servo from everything else...right.
>
> I first tried (at the manufacturer's request) a pair of capacitors (.1uf
and
> 4700uf) in parallel, grounded off the servo power lead itself. This did
> slightly dampen the noise, but certainly not enough.
[Barry] I gather the 47000uf cap was an electrolytic and the other was a
ceramic disc?
> So, I also went out
> and purchased a common 10-amp car audio power filter - just like those
sold
> by Radio Shack and documented by Bob on his site - 2 caps with a choke
coil
> potted in a case although I can not see the ratings on the caps.
> I placed the filter in an orientation that isolated the power source from
the servo,
> instead of servo from power source as IT was the verified source of the
> noise.
[Barry] I'm not sure what you mean my that statement.
Is the filter mounted as close to the servo as posable, short leads and a
clean ground? That is how it should be installed.
>
> The good news is, that filter eliminated about 99% of the noise - and
that's
> good to go. I have not yet done extensive tests to see if the AP now
> operates properly in flight with the filter in-line (possible I/O errors,
> proper servo feedback, etc)...that's coming soon. But, I want to explore
> the "weirdness" first.
>
> Now, the weird (to me anyway) part is that the filter itself now audibly
> "sings" with the same frequency that I had heard before on the intercom.
I
> mean, it literally makes the noise like a speaker would. Is this normal?
[Barry] Weird to me too? Are you saying that the filter has a noise coming
from it? If so then your GROUND is poor and maybe your leads too long. This
of course is assuming that the filter is made well and the coils of the filter
are mounted / potted securely. But, the first thing I would check is the
GROUND.
Other thing to check would be your crimps. I would rather have you tell me
that you soldered these connection.
Barry
"Chop'd Liver"
"Show them the first time, correct them the second time, kick them the third
time."
Yamashiada
________________________________________________________________________________
| Subject: | Re: flap deployment above Vfe |
| From: | Jon & Kathryn Hults <legacy(at)speedband.com> |
Military fighter pilots have had much more "consequential" switches on their
throttles and sticks for quite some time. The theory behind HOTAS (Hands On
Throttle And Stick) is that you are less likely to make flight path
deviations if you keep your hands on the controls...and less likely to run
into something if you don't have to look inside to throw a switch. Makes
sense to me.
The trick is in the design of the stick. The top buttons which should
probably be reserved for "consequential" switches (trim, flaps, speedbrakes,
spoilers, etc..) are out of reach with a normal grasp on the stick. A
conscious movement of the thumb is required to activate these switches. You
do have to learn where the switches are and not to touch them when you don't
want them to move. We all learned that way back in the beginning from our
flight instructors...didn't we?
If you want to be sure you can't activate the flaps in cruise flight, try
this http://www.aircraftextras.com/ It uses a relay board to disable the
flap switch above max flap speed to avoid inadvertent flap extension.
I think HOTAS is another great idea that will lead to safer flying in all of
general aviation thanks to experimental builders like us.
My opinion, for what it's worth.
Jon Hults
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Noise filter noise |
On Aug 25, 2006, at 11:17 AM, James Redmon wrote:
> Now, the weird (to me anyway) part is that the filter itself now
> audibly "sings" with the same frequency that I had heard before on
> the intercom. I mean, it literally makes the noise like a speaker
> would. Is this normal? What would be causing that? Is this
> symptomatic of some additional problem that might effect servo
> operation? Something else I should do or try?
You are putting current pulses through an inductor so it has a
magnetic field that is varying with the current pulses. Any steel
object nearby is going to be alternately pulled and released by the
varying magnetic field. It is probably the case of the inductor or
the inductor's core that is making the noise.
OTOH, there shouldn't be that much current change. Put the capacitor
combo back at the input to the servo.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Problems with High EGT readings |
On Aug 25, 2006, at 1:52 PM, Ron Patterson wrote:
> Hey all,
> I've just begun to have 1450+ EGT readings on all cylinders, while
> the CHT's remain below 390 degrees. No attempt to richen things up
> (carb heat for example) improves things. I took off the cowl and
> see no exterior signs of trouble, removed spark plugs and they are
> nice and tan and even wet from running too rich. I tried a brief
> flight and all was normal, then on the next long leg they did it
> again. I recycled the Grand Rapids EIS and then only one cylinder
> persisted in giving me this reading. Am I right to assume it is an
> indicator/gauge issue or am I missing something more ominous?
If you have a sudden high EGT on all cylinders, check to see if one
mag has stopped working. If both mags are normal and CHTs are normal,
look for a gauge problem.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | Dave N6030X <N6030X(at)DaveMorris.com> |
| Subject: | Re: Noise filter noise |
Well, 2.5 KHz is within the audible frequency range. The A above
Middle C is 440 Hz. So you're only talking about less than 6 octaves
above it. All it would take is having the coil inside the filter
that has this frequency applied to it being physically in contact
with the case or other structure. I can envision that real
easily. We usually call that "headphones" or "loud speaker". So,
you might have to take it apart and make sure the filter is
physically isolated from the box around it using RTV or rubber
gaskets or something.
Be careful about filtering the PWM signal, though. The whole purpose
is to feed that signal to the servo, and if you are applying a filter
that changes the shape, the servo might start functioning incorrectly.
Dave Morris
At 01:17 PM 8/25/2006, you wrote:
>
>Hi all,
>
>I'm wondering if someone could educate me a little on something I
>encountered while trying to eliminate electrical noise coming from
>an autopilot servo. The story goes like this:
>
>I recently installed a new autopilot servo in my Berkut (all
>composite). It worked perfectly, but for some reason, the servo
>makes a loud squealing noise in the intercom audio when it's
>activated. I did all the usual things - changed ground points,
>increased grounding, double checked shielding on cables, un-bundled
>wires, ferrite beads on the cables, etc. The only thing that really
>worked was to power the servo from a separate battery - indicating
>electrical propagation, not RF. I spoke with the manufacturer, and
>they did mention that there was a 2.5KHz PWM signal that is used to
>control the servo, and that the "noise" I hear is likely that. So,
>on to trying to isolate the servo from everything else...right.
>
>I first tried (at the manufacturer's request) a pair of capacitors
>(.1uf and 4700uf) in parallel, grounded off the servo power lead
>itself. This did slightly dampen the noise, but certainly not
>enough. So, I also went out and purchased a common 10-amp car audio
>power filter - just like those sold by Radio Shack and documented by
>Bob on his site - 2 caps with a choke coil potted in a case although
>I can not see the ratings on the caps. I placed the filter in an
>orientation that isolated the power source from the servo, instead
>of servo from power source as IT was the verified source of the noise.
>
>The good news is, that filter eliminated about 99% of the noise -
>and that's good to go. I have not yet done extensive tests to see
>if the AP now operates properly in flight with the filter in-line
>(possible I/O errors, proper servo feedback, etc)...that's coming
>soon. But, I want to explore the "weirdness" first.
>
>Now, the weird (to me anyway) part is that the filter itself now
>audibly "sings" with the same frequency that I had heard before on
>the intercom. I mean, it literally makes the noise like a speaker
>would. Is this normal? What would be causing that? Is this
>symptomatic of some additional problem that might effect servo
>operation? Something else I should do or try?
>
>All information and education is welcome...but remember, I'm not an EE. ;-)
>
>Eager to learn,
>
>James Redmon
>Berkut #013 N97TX
>http://www.berkut13.com
>
>
>By the way, this is not a common situation as the manufacturer has
>not seen this type of issue before...although they are doing
>everything they can to get this under control - under warranty, to
>their credit! I have no issues with the way they are handling
>this..so please don't pester me about that part.
>
>
________________________________________________________________________________
| From: | FLYaDIVE(at)aol.com |
| Subject: | Re: Problems with High EGT readings |
In a message dated 8/25/06 8:41:24 PM Eastern Daylight Time,
brian-av(at)lloyd.com writes:
> If you have a sudden high EGT on all cylinders, check to see if one
> mag has stopped working. If both mags are normal and CHTs are normal,
> look for a gauge problem.
================================
Brian:
If you reduce your spark in half your EGT goes DOWN not UP. Loss of a Mag
reduces combustion efficiency. If the timing is incorrect EGT can go UP but
usually the Oil and CHT follows.
Ron said CHT was 390 F but he did not say that was his NORMAL ... Only that
is below 390F.
What Ron should be looking for is something that will cause LEANING ...
either Less Fuel or More Air.
My first place to look would be an AIR LEAK around the Carb.
Second place would be the rubber coupling on the intake, but the chances of
that are very slim since ALL cylinder increased EGT.
Third place is an EXHAUST Leak. Around the flanges ... Ron, you didn't use
those cheep soft exhaust gaskets?
I have a very difficult time believing that all 4 EGT probes drifted in the
same direction. Or that the EIS failed in such a manor that ONLY the EGT was
affected and not the CHT.
Barry
"Chop'd Liver"
"Show them the first time, correct them the second time, kick them the third
time."
Yamashiada
________________________________________________________________________________
| From: | "Jim Baker" <jlbaker(at)msbit.net> |
| Subject: | Re: Problems with High EGT readings |
X-mailer: Pegasus Mail for Windows (4.21c)
> If you reduce your spark in half your EGT goes DOWN not UP.
Loss of a
> Mag reduces combustion efficiency.
Nope. EGT should rise about 50 degrees F on all cylinders. Think a
bit more about this and you'll understand why it work this way....
Jim Baker
580.788.2779
'71 SV, 492TC
Elmore City, OK
________________________________________________________________________________
| From: | James Freeman <flyeyes(at)mac.com> |
| Subject: | Re: Problems with High EGT readings |
On Aug 25, 2006, at 3:52 PM, Ron Patterson wrote:
> Hey all,
> I've just begun to have 1450+ EGT readings on all cylinders, while
> the CHT's remain below 390 degrees. No attempt to richen things up
> (carb heat for example) improves things. I took off the cowl and
> see no exterior signs of trouble, removed spark plugs and they are
> nice and tan and even wet from running too rich. I tried a brief
> flight and all was normal, then on the next long leg they did it
> again. I recycled the Grand Rapids EIS and then only one cylinder
> persisted in giving me this reading. Am I right to assume it is an
> indicator/gauge issue or am I missing something more ominous?
> Thanks in advance for your ideas.
> Ron
> RV-4 N8ZD
Hi Ron
As Brian mentioned, loss of one ignition will cause all the EGTs to
rise simultaneously, along with a small loss of power and slightly
lower CHTs. I have had these exact symptoms caused by an ignition
failure in the climb--I noticed it when EGTs went well above their
normal peaks as I tried to lean. You can diagnose this quickly by
cycling the mags in the air, but this is probably best done without
your wife in the back seat (or so I've heard. At length.).
I think it's most likely an indicator issue, but would check ignition
first. I have a vague recollection of reading about similar symptoms
with an EIS with a wiring issue sometime in the last few weeks. You
might want to try Greg at Grand Rapids--he seems to be pretty
responsive. A search of the various RV/aerolelectric forums and
Doug's VAF site for "EIS" and "EGT" might turn up some relevant posts.
James Freeman
________________________________________________________________________________
| From: | Kelly McMullen <kellym(at)aviating.com> |
| Subject: | Re: Problems with High EGT readings |
Sorry Barry, but Brian is correct. Demonstrable on any mag check during
run up or an in flight mag check. The flame front propagates slower with
single ignition, and burns longer in the cylinder, making it hotter
coming out the exhaust.
FLYaDIVE(at)aol.com wrote:
>
> In a message dated 8/25/06 8:41:24 PM Eastern Daylight Time,
> brian-av(at)lloyd.com writes:
>
>> If you have a sudden high EGT on all cylinders, check to see if one
>> mag has stopped working. If both mags are normal and CHTs are normal,
>> look for a gauge problem.
> ================================
> Brian:
>
> If you reduce your spark in half your EGT goes DOWN not UP. Loss of a Mag
> reduces combustion efficiency. If the timing is incorrect EGT can go UP but
> usually the Oil and CHT follows.
> Ron said CHT was 390 F but he did not say that was his NORMAL ... Only that
> is below 390F.
________________________________________________________________________________
| From: | OldBob Siegfried <oldbob(at)beechowners.com> |
| Subject: | Re: Problems with High EGT readings |
Good Evening Barry,
May I suggest that you rethink that a bit?
When operating on one magneto, the EGTs will rise.
Why?
Because the timing is effectively retarded and the
peak temperature occurs later in the combustion cycle.
The fire gets closer to the point where it is
measured. The actual peak combustion pressure and
temperature will both be lower, but due to the timing
change, the EGTs Will be higher.
Happy Skies,
Old Bob
--- FLYaDIVE(at)aol.com wrote:
> FLYaDIVE(at)aol.com
>
> In a message dated 8/25/06 8:41:24 PM Eastern
> Daylight Time,
> brian-av(at)lloyd.com writes:
>
> > If you have a sudden high EGT on all cylinders,
> check to see if one
> > mag has stopped working. If both mags are normal
> and CHTs are normal,
> > look for a gauge problem.
> ================================
> Brian:
>
> If you reduce your spark in half your EGT goes DOWN
> not UP. Loss of a Mag
> reduces combustion efficiency. If the timing is
> incorrect EGT can go UP but
> usually the Oil and CHT follows.
> Ron said CHT was 390 F but he did not say that was
> his NORMAL ... Only that
> is below 390F.
>
> What Ron should be looking for is something that
> will cause LEANING ...
> either Less Fuel or More Air.
> My first place to look would be an AIR LEAK around
> the Carb.
> Second place would be the rubber coupling on the
> intake, but the chances of
> that are very slim since ALL cylinder increased EGT.
>
> Third place is an EXHAUST Leak. Around the flanges
> ... Ron, you didn't use
> those cheep soft exhaust gaskets?
> I have a very difficult time believing that all 4
> EGT probes drifted in the
> same direction. Or that the EIS failed in such a
> manor that ONLY the EGT was
> affected and not the CHT.
>
> Barry
> "Chop'd Liver"
>
> "Show them the first time, correct them the second
> time, kick them the third
> time."
> Yamashiada
>
>
> browse
> Subscriptions page,
> FAQ,
> http://www.matronics.com/Navigator?AeroElectric-List
>
> Web Forums!
>
>
> Admin.
>
>
>
>
>
________________________________________________________________________________
| Subject: | Re: Problems with High EGT readings |
| From: | "Matt Prather" <mprather(at)spro.net> |
Turning off one mag slows down the combustion process - effectively
retarding the spark timing. That will cause the EGT to rise because more
of the fuel air mixture will be left burning when the exhaust valve opens.
Cylinder pressure WILL be lower..
See John Deak and George Braly for more info. Or.. Try it on your plane.
Regards,
Matt-
FLYaDIVE(at)aol.com wrote:
>
>In a message dated 8/25/06 8:41:24 PM Eastern Daylight Time,
>brian-av(at)lloyd.com writes:
>
>>If you have a sudden high EGT on all cylinders, check to see if one
>> mag has stopped working. If both mags are normal and CHTs are normal,
>> look for a gauge problem.
>
>================================
>Brian:
>
>If you reduce your spark in half your EGT goes DOWN not UP. Loss of a Mag
>reduces combustion efficiency. If the timing is incorrect EGT can go UP but
>usually the Oil and CHT follows.
>Ron said CHT was 390 F but he did not say that was his NORMAL ... Only that
>is below 390F.
>
>What Ron should be looking for is something that will cause LEANING ...
>either Less Fuel or More Air.
>My first place to look would be an AIR LEAK around the Carb.
>Second place would be the rubber coupling on the intake, but the chances of
>that are very slim since ALL cylinder increased EGT.
>Third place is an EXHAUST Leak. Around the flanges ... Ron, you didn't use
>those cheep soft exhaust gaskets?
>I have a very difficult time believing that all 4 EGT probes drifted in the
>same direction. Or that the EIS failed in such a manor that ONLY the EGT
was
>affected and not the CHT.
>
>Barry
>"Chop'd Liver"
>
>"Show them the first time, correct them the second time, kick them the third
>time."
>Yamashiada
>
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Problems with High EGT readings |
On Aug 25, 2006, at 6:59 PM, FLYaDIVE(at)aol.com wrote:
>
> In a message dated 8/25/06 8:41:24 PM Eastern Daylight Time,
> brian-av(at)lloyd.com writes:
>
>> If you have a sudden high EGT on all cylinders, check to see if one
>> mag has stopped working. If both mags are normal and CHTs are
>> normal,
>> look for a gauge problem.
> ================================
> Brian:
>
> If you reduce your spark in half your EGT goes DOWN not UP.
Normally I try to be diplomatic but in this case I will make an
exception. You are just plain wrong.
Proof:
Turn off one mag in cruise and watch your EGT go up by about 100F.
Reason:
With both mags working you have two flame-fronts in the combustion
chamber. This means that combustion completes sooner allowing more
time for the gas to transfer heat to the components in the cylinder
thus leading to cooler gas going out the exhaust. When you turn off
one mag you have only one flame front and the combustion time is
slightly longer. There is now less time after the end of combustion
and before the exhaust valve opens so your EGT is higher.
> Loss of a Mag reduces combustion efficiency.
Yeah, so?
> If the timing is incorrect EGT can go UP but
> usually the Oil and CHT follows.
Actually, if you get advanced timing your CHT will go up but your EGT
will go down for the reasons I outlined above. Detonation will do the
same thing.
> Ron said CHT was 390 F but he did not say that was his NORMAL ...
> Only that
> is below 390F.
I read that to mean that he did not see an increase in CHT.
>
> What Ron should be looking for is something that will cause
> LEANING ...
Perhaps. The simplest explanation for a 100F rise in EGT across all
cylinders without a rise in CHT is the loss of a mag. (Actually CHT
will drop slightly as less heat is transferred to the head.) It is
also pitifully easy to check. After that it is time for more
difficult tests and inspections.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | "James Redmon" <james(at)berkut13.com> |
| Subject: | Re: Noise filter noise |
>> I recently installed a new autopilot servo in my Berkut (all composite).
> It
>> worked perfectly, but for some reason, the servo makes a loud squealing
>> noise in the intercom audio when it's activated.
>
> [Barry] When what is activated, the intercom or the servo?
When the servo is active. The squeal is itermittent but coupled with the
motion of the servo. As in when pressure is applied against the stick and
the servo is commanded to move the other direction. This was without the
filter installed, of course.
>> I did all the usual
>> things - changed ground points, increased grounding, double checked
>> shielding on cables, un-bundled wires, ferrite beads on the cables, etc.
>> The only thing that really worked was to power the servo from a separate
>> battery - indicating electrical propagation, not RF. I spoke with the
>> manufacturer, and they did mention that there was a 2.5KHz PWM signal
>> that
>> is used to control the servo, and that the "noise" I hear is likely
>> that.
>> So, on to trying to isolate the servo from everything else...right.
>>
>> I first tried (at the manufacturer's request) a pair of capacitors (.1uf
> and
>> 4700uf) in parallel, grounded off the servo power lead itself. This did
>> slightly dampen the noise, but certainly not enough.
>
> [Barry] I gather the 47000uf cap was an electrolytic and the other was a
> ceramic disc?
Yup. The cap combo didn't do much to squelch the noise. The filter cuts it
by 99%.
>> So, I also went out
>> and purchased a common 10-amp car audio power filter - just like those
> sold
>> by Radio Shack and documented by Bob on his site - 2 caps with a choke
> coil
>> potted in a case although I can not see the ratings on the caps.
>
>> I placed the filter in an orientation that isolated the power source from
> the servo,
>> instead of servo from power source as IT was the verified source of the
>> noise.
>
> [Barry] I'm not sure what you mean my that statement.
> Is the filter mounted as close to the servo as posable, short leads and a
> clean ground? That is how it should be installed.
Yes, they are short - about 3" from servo. I rigged up a short pig-tail so
I could attach it and detach it for testing. I just mean that the filter
is a stimple choke coil with a two caps in parallel like Bob has documented:
http://www.aeroelectric.com/articles/filter/RS_Noise_Filters.pdf#search=%22filter%22
>> The good news is, that filter eliminated about 99% of the noise - and
> that's
>> good to go. I have not yet done extensive tests to see if the AP now
>> operates properly in flight with the filter in-line (possible I/O
>> errors,
>> proper servo feedback, etc)...that's coming soon. But, I want to
>> explore
>> the "weirdness" first.
>>
>> Now, the weird (to me anyway) part is that the filter itself now audibly
>> "sings" with the same frequency that I had heard before on the intercom.
> I
>> mean, it literally makes the noise like a speaker would. Is this
>> normal?
>
> [Barry] Weird to me too? Are you saying that the filter has a noise
> coming
> from it? If so then your GROUND is poor and maybe your leads too long.
> This
> of course is assuming that the filter is made well and the coils of the
> filter
> are mounted / potted securely. But, the first thing I would check is the
> GROUND.
Yup. the filter itself is the source of the audible noise. It is connected
to the common "nose" ground block. That block is fat wired striaght back to
the battery. I'm not sure what else to "check" or how. I have opened the
filter's case up, but it's components are potted with glue and I can't read
the cap values. But I can see that it's just a coil, and two caps in a
plastic case.
> Other thing to check would be your crimps. I would rather have you tell
> me
> that you soldered these connection.
All PIDG crimps. All have been checked as secure.
Filter still singing like a canary.
James Redmon
Berkut #013 N97TX
http://www.berkut13.com
________________________________________________________________________________
| From: | "James Redmon" <james(at)berkut13.com> |
| Subject: | Re: Noise filter noise |
> You are putting current pulses through an inductor so it has a magnetic
> field that is varying with the current pulses. Any steel object nearby is
> going to be alternately pulled and released by the varying magnetic
> field. It is probably the case of the inductor or the inductor's core
> that is making the noise.
Humm...might be the inductor core..it's not mounted near anything else (6"+
minimum). The noise is definately coming from inside the filter case
(plastic) and I can feel it vibrating with the sound.
> OTOH, there shouldn't be that much current change. Put the capacitor
> combo back at the input to the servo.
The cap combo didn't do much at all to help the noise. Maybe a 5%
reduction.
Thanks for the input!
James Redmon
Berkut #013 N97TX
http://www.berkut13.com
________________________________________________________________________________
| From: | "James Redmon" <james(at)berkut13.com> |
| Subject: | Re: Noise filter noise |
> Well, 2.5 KHz is within the audible frequency range. The A above Middle C
> is 440 Hz. So you're only talking about less than 6 octaves above it.
> All it would take is having the coil inside the filter that has this
> frequency applied to it being physically in contact with the case or other
> structure. I can envision that real easily. We usually call that
> "headphones" or "loud speaker". So, you might have to take it apart and
> make sure the filter is physically isolated from the box around it using
> RTV or rubber gaskets or something.
Well, the caps and coil are in a plastic case, and are installed with some
kind of clear gel glue - like hot glue. I can not see that anything is
touching the case without the goop inbetween.
> Be careful about filtering the PWM signal, though. The whole purpose is
> to feed that signal to the servo, and if you are applying a filter that
> changes the shape, the servo might start functioning incorrectly.
Yeah. There does not seem to be any issues with the servo operation, but
then I have not flown it either. I will do some flight testing tomorrow.
I also plan to disconnect the filter, setup the AP servo, get it working in
flight (if I can bear the noise in the headset), and then re-connect the
filter and see if there are any servo problems.
I'll know more tomorrow. One thing - I can live with the singing filter if
the AP works properly. It's not loud enough to hear over any engine
noise....but the noise over the headsets is LOUD!
James Redmon
Berkut #013 N97TX
http://www.berkut13.com
________________________________________________________________________________
| From: | "Richard Girard" <jindoguy(at)gmail.com> |
| Subject: | Re: Noise filter noise |
I've had singing capacitors in audio equipment before, it means it's a bad
capacitor. Try replacing it or the whole filter assembly.
Rick
On 8/25/06, James Redmon wrote:
>
> james(at)berkut13.com>
>
> > Well, 2.5 KHz is within the audible frequency range. The A above Middle
> C
> > is 440 Hz. So you're only talking about less than 6 octaves above it.
> > All it would take is having the coil inside the filter that has this
> > frequency applied to it being physically in contact with the case or
> other
> > structure. I can envision that real easily. We usually call that
> > "headphones" or "loud speaker". So, you might have to take it apart and
> > make sure the filter is physically isolated from the box around it using
> > RTV or rubber gaskets or something.
>
> Well, the caps and coil are in a plastic case, and are installed with some
> kind of clear gel glue - like hot glue. I can not see that anything is
> touching the case without the goop inbetween.
>
> > Be careful about filtering the PWM signal, though. The whole purpose is
> > to feed that signal to the servo, and if you are applying a filter that
> > changes the shape, the servo might start functioning incorrectly.
>
>
> Yeah. There does not seem to be any issues with the servo operation, but
> then I have not flown it either. I will do some flight testing tomorrow.
>
> I also plan to disconnect the filter, setup the AP servo, get it working
> in
> flight (if I can bear the noise in the headset), and then re-connect the
> filter and see if there are any servo problems.
>
> I'll know more tomorrow. One thing - I can live with the singing filter
> if
> the AP works properly. It's not loud enough to hear over any engine
> noise....but the noise over the headsets is LOUD!
>
>
> James Redmon
> Berkut #013 N97TX
> http://www.berkut13.com
>
>
--
Rick Girard
"Ya'll drop on in"
takes on a whole new meaning
when you live at the airport.
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Noise filter noise |
On Aug 25, 2006, at 9:58 PM, James Redmon wrote:
>
>
>> You are putting current pulses through an inductor so it has a
>> magnetic field that is varying with the current pulses. Any steel
>> object nearby is going to be alternately pulled and released by
>> the varying magnetic field. It is probably the case of the
>> inductor or the inductor's core that is making the noise.
>
> Humm...might be the inductor core..it's not mounted near anything
> else (6"+ minimum). The noise is definately coming from inside the
> filter case (plastic) and I can feel it vibrating with the sound.
>
>
>> OTOH, there shouldn't be that much current change. Put the
>> capacitor combo back at the input to the servo.
>
> The cap combo didn't do much at all to help the noise. Maybe a 5%
> reduction.
I know that but it might help with the noise coming from the filter.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | "James Redmon" <james(at)berkut13.com> |
| Subject: | Re: Noise filter noise |
Humm...given the potting inside the filter, I think I'd end up
destroying it in the process of dis-assembly. I might try replacing the
whole filter.
Attached is a picture of the unit - I have not been able to track down
any electrical specifics.
Curious, if one of the two capacitors went bad, wouldn't it fail (at
least partially) to squelch the noise and no longer "filter" as well?
Or is there a partial failure mode of a capacitor that I'm not aware of?
Thank you all for the help and ideas - it's very educational.
I'll fly it today, and see if the servo is operating properly with and
without the filter attached. (it's rigged as a small jumper cable so I
can easily plug and un-plug it)
I think if the AP servo works properly, I'll just let the filter audibly
"sing". At least there's no appreciable noise in the headsets.
James Redmon
Berkut #013 N97TX
http://www.berkut13.com
----- Original Message -----
From: Richard Girard
To: aeroelectric-list(at)matronics.com
Sent: Saturday, August 26, 2006 2:09 AM
Subject: Re: AeroElectric-List: Noise filter noise
I've had singing capacitors in audio equipment before, it means it's a
bad capacitor. Try replacing it or the whole filter assembly.
Rick
________________________________________________________________________________
| Subject: | Master Relay Wiring |
| From: | "Barry Ward" <barry.ward(at)wanadoo.fr> |
Is it normal for the master relay to be connected directly to ground via the master
On switch? In the circuit recommended by Vans, which is probably an aviation
standard design, there is no fuse or circuit breaker in series with the current
flowing through the Master relay coil.
Every other circuit seems to have a protection device wired in series.
Perhaps someone could explain why?
Barry RV6A
--------
Barry
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=57540#57540
________________________________________________________________________________
| Subject: | Re: Master Relay Wiring |
Hi Barry,
>
> Is it normal for the master relay to be connected directly to ground via the
master On switch?
Yes
> there is no fuse or circuit breaker in series with the current flowing through
the Master relay coil.
> Every other circuit seems to have a protection device wired in series.
> Perhaps someone could explain why?
>
The fuse or CB protects the wire against overheating due to excessive
current intensity. In this particular circuit, the current is limited by
the relay coil, so no protection is needed.
Hope this helps,
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
________________________________________________________________________________
| From: | Speedy11(at)aol.com |
Experts and Builders,
I have two questons for you.
1. Where did you physically locate your alternator cicuit breaker in your
airframe?
2. Is it a good idea to have a bus bar forward of the firewall to obtain
power for various sensors in the engine compartment?
Thank you.
Stan Sutterfield
________________________________________________________________________________
| From: | "Bill Bradburry" <bbradburry(at)allvantage.com> |
| Subject: | Thermocouple wire |
If I am going to buy wire to make my own "J" thermocouples, should I buy
stranded or solid wire for use in my plane? If I buy stranded, do I
silver solder the ends together the same as with solid wire? I am
looking at 24 AWG wire.
Does it make any difference whether you use "J" or "K" wire to the
instrument that you hook it up to? In other words, can you hook up "J"
wire to an EGT meter and use it to read CHT, or OAT, or oil temp, or
whatever? (I understand that you can hook up "K" wire to an EGT meter
and use it to read CHT..That is not what I am asking.. I am wondering if
the meter is calibrated to the type of wire)
Thanks,
Bill Bradburry
________________________________________________________________________________
| From: | "Greg Campbell" <gregcampbellusa(at)gmail.com> |
| Subject: | Transorbs for Lancair Flap Actuator... |
What size Transorb or MOV would be suitable for the flap motor on a Lancair
ES ?
They use an "FL1" 12v (or 24v) "linear actuator", Aircraft Spruce part #
05-66223
http://www.aircraftspruce.com/catalog/appages/flaplinact.php
Lancair provided the flap actuator, limit switches, and Omrom 12vdc relays.
I'm still using the "factory standard" schematic, but it doesn't utilize
diodes
or MOV's to protect the switches or relays. The flap motor is a pretty
healthy
size motor, I'm guessing the amp draw is around 8 or 10 amps.
The Lancair schematic shorts the two terminals of the flap motor together
when the flap is not in operation. This acts as an electronic brake
and noticeably minimizes any tendency to "coast".
If I wanted to add a transorb - would I just wire it in parallel with the
motor leads?
What size would I use? (Mine is a 12v system, but others have the 24v
model.)
Thanks,
Greg
________________________________________________________________________________
| Subject: | Re: Thermocouple wire |
"Bill Bradburry" wrote:
>
> If I am going to buy wire to make my own "J" thermocouples, should I buy
> stranded or solid wire for use in my plane? If I buy stranded, do I
> silver solder the ends together the same as with solid wire? I am
> looking at 24 AWG wire.
> Does it make any difference whether you use "J" or "K" wire to the
> instrument that you hook it up to? In other words, can you hook up "J"
> wire to an EGT meter and use it to read CHT, or OAT, or oil temp, or
> whatever? (I understand that you can hook up "K" wire to an EGT meter
> and use it to read CHT..That is not what I am asking.. I am wondering if
> the meter is calibrated to the type of wire)
>
> Thanks,
> Bill Bradburry
>
Hi Bill,
You need to use the type wire the instrument is calibrated for to get
an accurate reading. Each type of thermocouple has a characteristic
voltage vs temp. Type K thermocouples are better for higher temps like
the EGT, and Type J is more suitable for lower temps like CHT.
You can make a useful TC junction by twisting the wires together,
silver soldering, spot welding, etc. Although twisting the wires
together would only be suitable for temporary use, and you might not
have a very good junction but it would work. Silver solder might not
make an ideal junction but it would be stable. A good weld would be
best. I've made J thermocouples by twisting the wires together and
melting the joint in an ox/acetylene flame. I checked them in boiling
water and they were within a degree or two of the correct temperature.
The effect of having a not perfect junction is that the voltage vs temp
will be lower than a good TC, but it will be stable for that particular
TC. In other words, with a "bad" junction temperature will read too
low.
One of the rotary engine guys, Todd Bartrim, has built Thermocouples
suitable for use as EGT probes. His procedure is documented
at http://www.rotarywiki.org/wiki/tiki-index.php?page=EgtThermocouples
Bob W.
--
http://www.bob-white.com
N93BD - Rotary Powered BD-4 (first engine start 1/7/06)
Custom Cables for your rotary installation -
http://www.roblinphoto.com/shop/
________________________________________________________________________________
| From: | Brian Lloyd <brian-av(at)lloyd.com> |
| Subject: | Re: Two Questions |
On Aug 26, 2006, at 12:59 PM, Speedy11(at)aol.com wrote:
> Experts and Builders,
> I have two questons for you.
> 1. Where did you physically locate your alternator cicuit breaker
> in your airframe?
I actually used a fuse forward of the firewall. If that sucker pops
you know you have a serious problem that you are not going to
troubleshoot in flight.
> 2. Is it a good idea to have a bus bar forward of the firewall to
> obtain power for various sensors in the engine compartment?
I guess that is up to you and the way you wire your engine
compartment. I didn't as there was nothing firewall forward that
needed power from the bus. My sensor box was powered from the display
in the panel so I didn't need to run power forward.
Brian Lloyd 361 Catterline Way
brian HYPHEN av AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
________________________________________________________________________________
| From: | "David M." <ainut(at)hiwaay.net> |
| Subject: | Re: Thermocouple wire |
Bill, I strongly recommend you get the wire already manufactured for
thermocouples. Aircraft Spruce has 15 foot lengths that you can cut to
the desired lengths for very little money. The type of wire is critical
to thermocouple usage.
David M.
Bill Bradburry wrote:
>
>If I am going to buy wire to make my own "J" thermocouples, should I buy
>stranded or solid wire for use in my plane? If I buy stranded, do I
>silver solder the ends together the same as with solid wire? I am
>looking at 24 AWG wire.
>Does it make any difference whether you use "J" or "K" wire to the
>instrument that you hook it up to? In other words, can you hook up "J"
>wire to an EGT meter and use it to read CHT, or OAT, or oil temp, or
>whatever? (I understand that you can hook up "K" wire to an EGT meter
>and use it to read CHT..That is not what I am asking.. I am wondering if
>the meter is calibrated to the type of wire)
>
>Thanks,
>Bill Bradburry
>
>
>
>
________________________________________________________________________________
| From: | "Bob McCallum" <robert.mccallum2(at)sympatico.ca> |
| Subject: | Re: Thermocouple wire |
Bill;
Stranded vs. solid is your choice but bear in mind that stranded is more
flexible and less prone to vibration fatigue than solid, but both will
function. Any point at which the two different wire alloys are joined forms
a thermocouple junction capable of generating a voltage and thus measuring
temperature. Twisting them together works, just not very long term reliable,
hence welding or silver solder can be used. Yes the instrument is calibrated
to the type of wire. The voltage vs. temperature curves for all the various
types of thermocouple wire (J, K, T, E, R, S, C,GB, etc) are quite different
and the instrument range and calibration must match the wire. One reason for
the multitude of types is to be able to measure temperatures through
different ranges. Thus your EGT and CHT thermocouples may well be different
types as might your OAT if you chose to use a thermocouple. Type J - Zero to
750 deg C Type K - minus 200 to 1250 deg C Type E - minus 200 to 900 deg C
Type T - minus 250 to 350 deg C etc.
ob McC
----- Original Message -----
From: "Bill Bradburry" <bbradburry(at)allvantage.com>
Sent: Saturday, August 26, 2006 4:41 PM
Subject: AeroElectric-List: Thermocouple wire
>
> If I am going to buy wire to make my own "J" thermocouples, should I buy
> stranded or solid wire for use in my plane? If I buy stranded, do I
> silver solder the ends together the same as with solid wire? I am
> looking at 24 AWG wire.
> Does it make any difference whether you use "J" or "K" wire to the
> instrument that you hook it up to? In other words, can you hook up "J"
> wire to an EGT meter and use it to read CHT, or OAT, or oil temp, or
> whatever? (I understand that you can hook up "K" wire to an EGT meter
> and use it to read CHT..That is not what I am asking.. I am wondering if
> the meter is calibrated to the type of wire)
>
> Thanks,
> Bill Bradburry
>
>
________________________________________________________________________________
| From: | Harley <harley(at)AgelessWings.com> |
| Subject: | Re: Thermocouple wire |
________________________________________________________________________________
| Subject: | Re: Transorbs for Lancair Flap Actuator... |
| From: | "Eric M. Jones" <emjones(at)charter.net> |
> What size Transorb or MOV would be suitable for the flap motor on a Lancair ES
? They use an "FL1" 12v (or 24v) "linear actuator", Aircraft Spruce part # 05-66223
.....
>
> Lancair provided the flap actuator, limit switches, and Omrom 12vdc relays. I'm
still using the "factory standard" schematic, but it doesn't utilize diodes
or MOV's to protect the switches or relays. The flap motor is a pretty healthy
size motor, I'm guessing the amp draw is around 8 or 10 amps.
>
> The Lancair schematic shorts the two terminals of the flap motor together
> when the flap is not in operation. This acts as an electronic brake
> and noticeably minimizes any tendency to "coast".
>
> If I wanted to add a transorb - would I just wire it in parallel with the motor
leads? What size would I use? (Mine is a 12v system, but others have the 24v
model.) Thanks, Greg
Greg,
Transient supressors are installed so as to shunt the inductive coil in a relay
or motor, and also to shunt to ground the positive leads on bidirectional motors.
The SnapJack suppressors on my website are fine and I show the places to
mount them. For 24-28V systems us 600 mA 36V bidirectional transorbs.
--------
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=57844#57844
________________________________________________________________________________
| From: | "James Redmon" <james(at)berkut13.com> |
| Subject: | Noise filter noise |
An update to the noise issues:
Well, in short, the noise problems are solved. The test flights showed that
the filter disrupted the PWM signal to the extent that it was un-flyable.
So, the quick fix "filter" solution was not possible.
I tried various combinations of grounds and power and the only combination
that eliminated the noise was feeding the unit directly from the battery and
grounding it only to the battery as well. This meant isolating the unit's
mounting so that it did not touch a ground in the front of the plane
(battery is in the back).
So, with this combination required tearing the plane apart to install
dedicated lines (all out of spares), but at least all systems are functional
and quite happy with one another. The one combination I didn't try was to
install the filter on the intercom or audio circuit itself. I figured I'd
take the simplest route to solve the problem as protecting the audio may
have opened the door to at least 6 different sources (2 coms, audio panel,
intercom, engine monitor, etc.). Yikes!
Moral: if you are still building, do yourself a favor and pre-installed
triple the number of fore-aft wires that you think you need - you'll run our
of spares before you know it. ;-)
Anyway, the AP tracks dead-nuts-straight-on...and no noise to boot. All
smiles here...despite the bloody knuckles and pricked fingers.
Thanks to those offering explanations and ideas. I learned a lot on this
one.
James Redmon
Berkut #013 N97TX
http://www.berkut13.com
________________________________________________________________________________
| From: | "Jim Jewell" <jjewell(at)telus.net> |
| Subject: | Davd Clark X-11 headset review? |
Hello listers,
The David Clark Co. Inc. website offers what apears to be a new headset
called X 11.
The promo on the website looks good
I have not heard or found any other reports pro or can about this product.
Would anyone care to offer opinions based on actual use?
Jim in Kelowna - final inspection soon
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckollsr(at)cox.net> |
| Subject: | Re: Engine Kick-Back IO-360 |
>
> > --> RV-List message posted by: "J. R. Dial" <jrdial@hal-pc.org>
> >
> > I did not break a starter but the inrush current to the
> > permanent magnet starter I had dropped my voltage low enough that it
> > was
> > below the compliance voltage for the electronic ignition. I changed
> > it
> > out for a wound field starter and the problem was solved.
> > If you want to know brand names etc. email me off list.
>
>Now here is a problem I've never heard of before.
>Does anyone else have this problem and can it be
>resolved without changing out starters ?
>Larry Mac Donald
>lm4(at)juno.com
>Rochester N.Y.
>Do not achcive
This "problem" and "solution" has been around for
a long time. When the volumes of rare-earth magnet
motors was taking off in the market place (and prices
coming down) we (at B&C) considered a change-over
to the burgeoning technology.
The change was rejected for several reasons but
prominent among them was the extra-ordinary "locked-
rotor" current characteristics of the PM motor.
This did not present a systems issue with respect
to getting the engine running but we were already aware
of problems that some companies had with respect to
momentary "brownouts" during the first phases of
engine cranking. A typical system voltage transient
during first closure of starter contactor may be
seen at:
http://www.aeroelectric.com/Pictures/Curves/95_GMC_Safari_1.gif
http://www.aeroelectric.com/Pictures/Curves/95_GMC_Safari_3.gif
http://www.aeroelectric.com/Pictures/Curves/99_Saturn_SL1.jpg
http://www.aeroelectric.com/Pictures/Curves/99_Saturn_SL1_2.gif
These are battery terminal voltages taken from
our cars. The batteries are in excellent health. Note in
particular, the last curve where the battery voltage
stays below 9.0 volts (DO-160 recommended, "stay awake"
voltage level) for about 50 mS. If the ignition system
(or any other accessory) shared any supply current
paths with the starter the voltage drops on wires would
exacerbate the brown out conditions illustrated.
Unfortunately, many folks who would sell to either the
TC or OBAM aviation worlds do not take the DO-160 recommendations
to heart and ignore the realities of cranking systems operation,
they allow their products loose in the wild with unhappy
vulnerabilities to such transients.
Sometimes it's an extended reboot interval for a computer based
accessory, or timing for an ignition system wherein
the system delivers spark at the wrong times.
One of several reasons B&C elected to stay with
wound fields was to reduce probability that their product
would be cited as "root cause" of problems with other
systems. Contrary to popular myth, starters are NEVER
root cause for misbehavior of another system, only
a piece of a puzzle at best . . . for issues that
would not have arisen had manufacturers of the "victimized"
systems done their homework.
Bob . . .
________________________________________________________________________________
| Subject: | Turn on ALT before engine start? |
| From: | "Bill Denton" <bdenton(at)bdenton.com> |
In an airplane equipped with a Continental 0-200, would you want to turn on the
ALT switch before engine start, or after?
Thanks!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=57936#57936
________________________________________________________________________________
| From: | "Bob Verwey " <bonanza(at)vodamail.co.za> |
| Subject: | Re: Transorbs for Lancair Flap Actuator... |
Greg,
Could you post that part of the circuit (or sketch) showing the "brake"
system relays where it "shorts" the motor leads. Working on something
similar for a homebuilt project with 28v. Also where you would put the
transorbs.
Thanx
Bob Verwey
A35 Bonanza ZU-DLW
________________________________________________________________________________
| From: | "Johnson, Phillip (EXP)" <phillip.johnson(at)lmco.com> |
| Subject: | Re: Noise filter noise |
The core of the inductor is probably lightly magnetostrictive which will
cause the core to vibrate under electrical excitation. This is normal,
however if the mechanical resonance of the core is close to the
excitation frequency then it will howl quite loudly and may induce
premature failure of adjacent components. If this is the case then you
can damp the vibration by adding some silicone or epoxy to the inductor.
This will move the natural frequency and damp the vibration.
Phillip Johnson
L
Chief Engineer & Manager Underwater Systems Group
Tel (613) 599 3280 ext. 3232
Cell (613) 799 1644
FAX (613) 599 3282
________________________________________________________________________________
| Subject: | Transorbs for Lancair Flap Actuator... |
| From: | "Bishop, Robert C MSgt 21 MOF/CCA" <robert.bishop(at)peterson.af.mil> |
TWIMC,
How on earth can I get off this "Chat Board" distribution list? I get
about 300 unwanted e-mails a day... Any help would be appreciated.
Thanks
MSgt Robert Bishop
21 MOF/CCA
W: 556-6527 (DSN 834)
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bob
Verwey
Sent: Monday, August 28, 2006 6:57 AM
Subject: Re: AeroElectric-List: Transorbs for Lancair Flap Actuator...
Greg,
Could you post that part of the circuit (or sketch) showing the "brake"
system relays where it "shorts" the motor leads. Working on something
similar for a homebuilt project with 28v. Also where you would put the
transorbs.
Thanx
Bob Verwey
A35 Bonanza ZU-DLW
________________________________________________________________________________
| From: | "Dale Ensing" <densing(at)carolina.rr.com> |
| Subject: | Re:How to unsubscribe |
Mr. Bishop,
go to http://www.matronics.com/subscription and follow instruction to
unsubscribe.
DWE
do not archieve
----- Original Message -----
From: "Bishop, Robert C MSgt 21 MOF/CCA" <robert.bishop(at)peterson.af.mil>
Sent: Monday, August 28, 2006 9:36 AM
Subject: RE: AeroElectric-List: Transorbs for Lancair Flap Actuator...
MOF/CCA"
>
> TWIMC,
> How on earth can I get off this "Chat Board" distribution list? I get
> about 300 unwanted e-mails a day... Any help would be appreciated.
> Thanks
>
> MSgt Robert Bishop
> 21 MOF/CCA
> W: 556-6527 (DSN 834)
>
________________________________________________________________________________
| From: | Cory Emberson <bootless(at)earthlink.net> |
| Subject: | Re: Davd Clark X-11 headset review? |
Jim,
I didn't get a chance to wear them in-flight for my most recent headset
review (for Kitplanes - they hadn't been released before the deadline),
but when I tried them on at the booth, they were incredibly comfortable,
rivally the Bose X, and the audio quality was very good. If they have a
try and buy deal, I'd gibe it a shot. My immediate impression was that I
wished I could have flown them for the review.
best, Coryt
Jim Jewell wrote:
>
> Hello listers,
>
> The David Clark Co. Inc. website offers what apears to be a new
> headset called X 11.
>
> The promo on the website looks good
> I have not heard or found any other reports pro or can about this
> product.
>
> Would anyone care to offer opinions based on actual use?
>
> Jim in Kelowna - final inspection soon
>
>
August 22, 2006 - August 28, 2006
AeroElectric-Archive.digest.vol-ga