Today's Message Index:
----------------------
1. 01:29 AM - Re: Re: Bridge Diodes use (The Kuffels)
2. 07:07 AM - Re: Re: Bridge Diodes use (Bob White)
3. 08:15 AM - Re: Bridge Diodes use (Eric M. Jones)
4. 09:01 AM - Re: Starting the REAL electrical work on my 601XL (Gig Giacona)
5. 09:17 AM - Loran to VHF (B Tomm)
6. 09:32 AM - Re: Re: Starting the REAL electrical work on my 601XL (Hinde, Frank George (Corvallis))
7. 09:41 AM - Re: Re: Bridge Diodes use (Matt Prather)
8. 10:06 AM - Re: Drilling Switch holes in aluminum? (Robert Feldtman)
9. 10:25 AM - Re: Bridge Diodes use (Eric M. Jones)
10. 10:35 AM - Re: Re: Starting the REAL electrical work on my 601XL (Ken)
11. 10:41 AM - Re: Re: Bridge Diodes use (Ernest Christley)
12. 11:06 AM - Re: Re: Bridge Diodes use (Matt Prather)
13. 11:29 AM - Creation Of Wiring Diagram (Dave VanLanen)
14. 11:42 AM - Re: Drilling Switch holes in aluminum? (Ron Shannon)
15. 11:42 AM - "Dead horse" (Roger & Jean)
16. 11:57 AM - Re: Creation Of Wiring Diagram (Ernest Christley)
17. 12:27 PM - Re: Creation Of Wiring Diagram (LarryMcFarland)
18. 12:39 PM - Re: Creation Of Wiring Diagram (Vernon Little)
19. 12:58 PM - Re: Re: Bridge Diodes use (ptrotter@optonline.net)
20. 01:00 PM - Re: Creation Of Wiring Diagram (Hinde, Frank George (Corvallis))
21. 02:34 PM - Re: Re: Bridge Diodes use (Richard Tasker)
22. 05:40 PM - Re: Drilling Switch holes in aluminum? (Kevin Horton)
23. 09:06 PM - Boost pumps (Dennis Jones)
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Subject: | Re: Bridge Diodes use |
Eric,
Still don't follow you.
I said:
<< If one diode is running 20 amps with a forward voltage of 0.6
then it generates 0.6 x 20 = 12 watts of heat. If two diodes in
parallel are carrying the same 20 amps then the current is split
between the two diodes .. each diode is generating about half of
12 watts with a total generation of still only 12 watts not 24. >>
You said:
<< If either one or two or a hundred conventional diodes is
sharing the load, they still dissipate Vf X A. >>
Agreed. But each diode is carrying a smaller fraction of the
same total amps so the total example heat generated remains 12
watts. Put algebraically:
Let Vf x A = 12 Watts
Let 3 diodes in parallel carry the same total current so
Vf1 = Vf2 = Vf3 = Vf
a1 + a2 + a3 = A
Then
(Vf1 x a1) + (Vf2 x a2) + (Vf3 x a3) = Vf x (a1 + a2 + a3)
= Vf x A = 12 watts
<< Vf is not reduced by putting parts in parallel. >>
Never said it did reduce Vf. (I've always used 0.7V for silicon
and 0.3V for germanium in my minimal design work but a Vf of 0.6V
is close enough also for this discussion.) I did say it reduced
the current carried by each individual part.
<< but the package is what we bolt to the heat sink. >>
But the package in your example is still only generating 12 watts
of heat, not 24. See below.
<< claim that a B & C FWB, when wired so that two diodes are
parallel, would have a Vf of 0.6. It does not; the Vf is often
1.2 maybe, and someone incorrectly assumed that the diodes being
in parallel made the Vf sum 0.6. The very best conventional FWB
diodes are 0.9Vf at 10A for each diode (you can't buy these at
Radio Shack), so it dissipates (2X0.9X10A=) 18W VERY BEST CASE.,
and 24W worst case if the diodes are Vf=1.2. >>
As Matt says, a Vf of 1.2 is only true when the FWB is wired up
as a full wave rectifier. Then there are indeed two diodes
working in *series* for each half cycle with a Vf of about 1.3V.
Perhaps, you might be referring to the fact the forward voltage
drop across a single diode increases from the turn-on voltage
value with increasing current. This can get above 1 volt at high
currents. But your use of 0.6V clearly made the discussion at
the turn-on voltage point not the Vf at high current. The
situation is the same whether we talk about Vf at turn-on current
or Vf at high current as long as we remain consistent.
And as an aside, putting diodes in parallel brings us lower on
the current scale for each device and closer to its turn-on
voltage. In other words, putting diodes in parallel lowers
(slightly) the total heat generated for the same total current.
In parallel, each diode still has it's original Vf and since they
are in parallel they don't add voltages. Whether there is 1 or
100 diodes in the package, they are still only carrying the
original example 20 amps total with a voltage drop between the
input terminal and the output terminal of one Vf since there is
only one diode drop between the terminals no matter how many
diodes are wired in parallel in between.
<< FWB ... You could make your own, but it's easier to abandon
the concept entirely. >>
Not claiming to be a FWB fan for this application. Just don't
see how running 20 amps total across one diode drop doubles the
heat generated when another diode is added to share the same
current. Under this logic, 8 diodes in parallel would generate
96 watts, 16 would generate 192 watts, etc. which is obviously
not what you mean to imply.
Basically, do not see how wiring diodes in parallel causes their
forward voltage drops to add together as you seem to be saying.
Tom, AL7AU
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Subject: | Re: Bridge Diodes use |
If you look up single silicon diodes in the 10 A to 20 A current rating
on Mouser or Digikey, you will find the Vf is 1.1 Volts or higher for
most of them. For example, a 1N3210 (a 15 A unit) is 1.5 V at 15 amps.
Look up a 1N4007 rated at 1 amp. Vf is 1.1V. Eric is right on the
money on this. He is just saying you can't use 0.6 Volts for Vf because
you have two 1.2 volt devices in parallel.
Bob W.
On Wed, 11 Jun 2008 02:25:10 -0600
The Kuffels <kuffel@cyberport.net> wrote:
>
> Eric,
>
> Still don't follow you.
>
> I said:
> << If one diode is running 20 amps with a forward voltage of 0.6
> then it generates 0.6 x 20 = 12 watts of heat. If two diodes in
> parallel are carrying the same 20 amps then the current is split
> between the two diodes .. each diode is generating about half of
> 12 watts with a total generation of still only 12 watts not 24. >>
>
> You said:
> << If either one or two or a hundred conventional diodes is
> sharing the load, they still dissipate Vf X A. >>
>
> Agreed. But each diode is carrying a smaller fraction of the
> same total amps so the total example heat generated remains 12
> watts. Put algebraically:
>
> Let Vf x A = 12 Watts
> Let 3 diodes in parallel carry the same total current so
> Vf1 = Vf2 = Vf3 = Vf
> a1 + a2 + a3 = A
> Then
> (Vf1 x a1) + (Vf2 x a2) + (Vf3 x a3) = Vf x (a1 + a2 + a3)
> = Vf x A = 12 watts
>
> << Vf is not reduced by putting parts in parallel. >>
>
> Never said it did reduce Vf. (I've always used 0.7V for silicon
> and 0.3V for germanium in my minimal design work but a Vf of 0.6V
> is close enough also for this discussion.) I did say it reduced
> the current carried by each individual part.
>
> << but the package is what we bolt to the heat sink. >>
>
> But the package in your example is still only generating 12 watts
> of heat, not 24. See below.
>
> << claim that a B & C FWB, when wired so that two diodes are
> parallel, would have a Vf of 0.6. It does not; the Vf is often
> 1.2 maybe, and someone incorrectly assumed that the diodes being
> in parallel made the Vf sum 0.6. The very best conventional FWB
> diodes are 0.9Vf at 10A for each diode (you can't buy these at
> Radio Shack), so it dissipates (2X0.9X10A=) 18W VERY BEST CASE.,
> and 24W worst case if the diodes are Vf=1.2. >>
>
> As Matt says, a Vf of 1.2 is only true when the FWB is wired up
> as a full wave rectifier. Then there are indeed two diodes
> working in *series* for each half cycle with a Vf of about 1.3V.
>
> Perhaps, you might be referring to the fact the forward voltage
> drop across a single diode increases from the turn-on voltage
> value with increasing current. This can get above 1 volt at high
> currents. But your use of 0.6V clearly made the discussion at
> the turn-on voltage point not the Vf at high current. The
> situation is the same whether we talk about Vf at turn-on current
> or Vf at high current as long as we remain consistent.
>
> And as an aside, putting diodes in parallel brings us lower on
> the current scale for each device and closer to its turn-on
> voltage. In other words, putting diodes in parallel lowers
> (slightly) the total heat generated for the same total current.
>
> In parallel, each diode still has it's original Vf and since they
> are in parallel they don't add voltages. Whether there is 1 or
> 100 diodes in the package, they are still only carrying the
> original example 20 amps total with a voltage drop between the
> input terminal and the output terminal of one Vf since there is
> only one diode drop between the terminals no matter how many
> diodes are wired in parallel in between.
>
> << FWB ... You could make your own, but it's easier to abandon
> the concept entirely. >>
>
> Not claiming to be a FWB fan for this application. Just don't
> see how running 20 amps total across one diode drop doubles the
> heat generated when another diode is added to share the same
> current. Under this logic, 8 diodes in parallel would generate
> 96 watts, 16 would generate 192 watts, etc. which is obviously
> not what you mean to imply.
>
> Basically, do not see how wiring diodes in parallel causes their
> forward voltage drops to add together as you seem to be saying.
>
> Tom, AL7AU
>
--
N93BD - Rotary Powered BD-4 - http://www.bob-white.com
3.8 Hours Total Time and holding
Cables for your rotary installation - http://roblinstores.com/cables/
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Subject: | Re: Bridge Diodes use |
> If you look up single silicon diodes in the 10 A to 20 A current rating
> on Mouser or Digikey, you will find the Vf is 1.1 Volts or higher for
> most of them. For example, a 1N3210 (a 15 A unit) is 1.5 V at 15 amps.
> Look up a 1N4007 rated at 1 amp. Vf is 1.1V. Eric is right on the
> money on this. He is just saying you can't use 0.6 Volts for Vf because
> you have two 1.2 volt devices in parallel.
> Bob W.
Yeah...What HE said...! Thanks, Bob White.
I can't in any reasonable time answer some previous posts, but there are a couple
issues that seem to confuse some people:
The FWB when used as Bob N. and B & C recommends uses two diodes in parallel. The
watts dissipated by the part at 20A is WORST CASE 1.2 x 20=24Watts.
The Vf of a diode is a strongly influenced by current. A diode can be 0.7 Vf at
zero Amps, and 1.0 Vf at 10A and 1.2 Vf at 12.5. For this you have to read the
data sheet. What?! Radio Shack doesn't supply one?! Then just guess and hope
you're right. Double up on the life insurance, too.
"In times of rapid change, experience could be your worst enemy."
--Jean Paul Getty
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones@charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=187361#187361
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Subject: | Re: Starting the REAL electrical work on my 601XL |
No, you are right that is a single point of failure and I'm not blowing you off
on the issue but is has been discussed to death in other forums and it has become
the standard method for the William Wynne Corvair conversion. Very quickly
the theory is in the case of an engine failure there is generally going to be
only to failure modes you can do anything about in the cockpit. One is the fuel
system and one is the ignition system. With the single switch design you put
in a fresh fuel pump and a fresh ignition system online. We do try to use the
best Mil-Spec switch we can find to at least reduce the chance. The theory
goes on that multiple switches introduces multiple single points of failure and
while we hate them they are in every plane that ever flew and it also introduces
switchology issues that have a greater chance of pilot error than does the
single switch.
I agree the more equipment fault resistant method would be 4 switches one for each
pump and one for each ignition. But in the case of an engine outage the pilot
then has to run through multiple switch settings to figure out the problem.
It all comes down to the guy that designed the conversion came up with this method
and there are a bunch of planes flying with it. I'm not tempted at this point
to change it.
[quote="mprather(at)spro.net]
It's possible I don't clearly understand how you'll be wiring the fuel
pumps and ignition system(s).. But it sounds like you are saying that
there will be a single switch controlling everything. If so, I believe
this switch represents a single point of failure, which is generally
undesirable for flight critical electrical items - at least when it comes
to switches... If the switch falls apart, the engine could stop
running(?).
Matt[/quote]
--------
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=187372#187372
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Bob,
Can a Loran antenna (CI 121 SP) be converted/trimmed into a VHF Comm.
antenna?
Thanks
Bevan
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Subject: | Re: Starting the REAL electrical work on my 601XL |
It also very easy to have 4 swithes in a prominent location as I do on the RV (electric
fuel pumps only) and did have on my 601HDS.
If the engine quits all 4 get banged upwards regardless...
As to adding points of failure this is simply untrue, you have a separate fuse,
wiring, switch for each discreet component...Its a fault tolerant design.
I understand that you are comfortable with the system and if that your chocie go
with it..William is a sharp guy but fuel pumps halfway up on the engine side
of the firewall (at least it was that way in the last picture I saw) is a vapour
lock prone design and single POF electrical system are two big no-nos for
me.
Frank
601 HDS 500 hours
RV7a (IO360) all electric
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Gig Giacona
Sent: Wednesday, June 11, 2008 8:57 AM
Subject: AeroElectric-List: Re: Starting the REAL electrical work on my 601XL
--> <wrgiacona@gmail.com>
No, you are right that is a single point of failure and I'm not blowing you off
on the issue but is has been discussed to death in other forums and it has become
the standard method for the William Wynne Corvair conversion. Very quickly
the theory is in the case of an engine failure there is generally going to be
only to failure modes you can do anything about in the cockpit. One is the fuel
system and one is the ignition system. With the single switch design you put
in a fresh fuel pump and a fresh ignition system online. We do try to use the
best Mil-Spec switch we can find to at least reduce the chance. The theory
goes on that multiple switches introduces multiple single points of failure and
while we hate them they are in every plane that ever flew and it also introduces
switchology issues that have a greater chance of pilot error than does the
single switch.
I agree the more equipment fault resistant method would be 4 switches one for each
pump and one for each ignition. But in the case of an engine outage the pilot
then has to run through multiple switch settings to figure out the problem.
It all comes down to the guy that designed the conversion came up with this method
and there are a bunch of planes flying with it. I'm not tempted at this point
to change it.
[quote="mprather(at)spro.net]
It's possible I don't clearly understand how you'll be wiring the fuel pumps and
ignition system(s).. But it sounds like you are saying that there will be a
single switch controlling everything. If so, I believe this switch represents
a single point of failure, which is generally undesirable for flight critical
electrical items - at least when it comes to switches... If the switch falls
apart, the engine could stop running(?).
Matt[/quote]
--------
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=187372#187372
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Subject: | Re: Bridge Diodes use |
I think this is the point that nobody was making.. Vf is not the knee
voltage. Bob White sent me a link to a Fairchild datasheet that showed
the I-V curve for one of their devices. Forward biasing conduction got
going around 0.6V - 0.7V, but at the rated current the voltage drop was up
around 1.0V - 1.1V. Eric, had you mentioned this early in the discussion,
I think we could have avoided a bunch of this churning...
http://www.fairchildsemi.com/ds/1N/1N4007.pdf
I still haven't seen where B&C stated that the voltage drop would be half
by running in parallel.. Certainly the voltage drop is reduced by running
the diode lower on the I-V curve for a given buss current.. But not by
half obviously. Maybe an estimate would be halfway between the published
Vf and the knee voltage.
Regards,
Matt
> The Vf of a diode is a strongly influenced by current. A diode can be
0.7
> Vf at zero Amps, and 1.0 Vf at 10A and 1.2 Vf at 12.5. For this you have
to read the data sheet. What?! Radio Shack doesn't supply one?! Then
just
> guess and hope you're right. Double up on the life insurance, too.
>
>
> "In times of rapid change, experience could be your worst enemy."
> --Jean Paul Getty
>
> --------
> Eric M. Jones
> www.PerihelionDesign.com
> 113 Brentwood Drive
> Southbridge, MA 01550
> (508) 764-2072
> emjones@charter.net
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=187361#187361
>
>
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Subject: | Re: Drilling Switch holes in aluminum? |
wouldn't the 1/2 inch do? 15/32 is only slightly smaller, I bet it would
work fine.
agree with dale's suggestion
bobf
On 6/10/08, Ron Shannon <rshannon@cruzcom.com> wrote:
>
>
> On Tue, Jun 10, 2008 at 3:51 PM, Dale Rogers <dale.r@cox.net> wrote:
>
>>
>> Ron,
>>
>> Wrong kind of "punch". Take a lot at the Harbor Freight # 91201 punch
>> set:
>>
>> [ http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=91201]
>>
>> One drills a center/pilot hole for the through-bolt, which pulls the two
>> halves of the punch together through the panel. No throat size to worry
>> about.
>>
>> Dale R.
>> COZY MkIV #0497
>> Ch. 13
>
>
> Yes, of course, but... still no 15/32" for the S700's.
>
> Ron
>
>
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Subject: | Re: Bridge Diodes use |
> I think this is the point that nobody was making.. Vf is not the knee voltage.
Bob White sent me a link to a Fairchild datasheet that showed the I-V curve
for one of their devices. Forward biasing conduction got going around 0.6V - 0.7V,
but at the rated current the voltage drop was up around 1.0V - 1.1V. Eric,
had you mentioned this early in the discussion, I think we could have avoided
a bunch of this churning...
> http://www.fairchildsemi.com/ds/1N/1N4007.pdf
> I still haven't seen where B&C stated that the voltage drop would be half
> by running in parallel.. Certainly the voltage drop is reduced by running
> the diode lower on the I-V curve for a given buss current.. But not by
> half obviously. Maybe an estimate would be halfway between the published Vf and
the knee voltage.
> Regards, Matt
Matt, et al.
See: http://www.bandc.biz/Diode_Installation.pdf
I don't claim that B & C ever stated that diodes' Vf could be summed like parallel
mosfets (etc.). But I saw the 0.6 Vf on their schematic as a very suspicious
indicator that somebody thought so, and that this should be attended to.
Yes, Matt, maybe I should have clarified some points earlier. But it was 100 degrees
yesterday, fer chis'sakes. Thanks for your sage input. (Ahem...which you
should have said earlier....)
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones@charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=187390#187390
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Subject: | Re: Starting the REAL electrical work on my 601XL |
Gig
I agree with you, keep it simple for single ignition and fuel injection.
A thought for anyone who has not followed such discussions though is the
case of systems that don't always fail passive. A real life example
would be that the the primary ignition system starts sending out
erratically timed sparks. My reflex action is to turn on the second
ignition and fuel pump if the engine hickups in any way. All switches
on. Time permitting, if that does not fix things, I next might try
turning off the primary ignition. There are cases where that restored
the engine. Can't do that though if the primary ignition is on the same
switch as single fuel injection.
Ken
Gig Giacona wrote:
> <wrgiacona@gmail.com>
>
> No, you are right that is a single point of failure and I'm not
> blowing you off on the issue but is has been discussed to death in
> other forums and it has become the standard method for the William
> Wynne Corvair conversion. Very quickly the theory is in the case of
> an engine failure there is generally going to be only to failure
> modes you can do anything about in the cockpit. One is the fuel
> system and one is the ignition system. With the single switch design
> you put in a fresh fuel pump and a fresh ignition system online. We
> do try to use the best Mil-Spec switch we can find to at least reduce
> the chance. The theory goes on that multiple switches introduces
> multiple single points of failure and while we hate them they are in
> every plane that ever flew and it also introduces switchology issues
> that have a greater chance of pilot error than does the single
> switch.
>
> I agree the more equipment fault resistant method would be 4 switches
> one for each pump and one for each ignition. But in the case of an
> engine outage the pilot then has to run through multiple switch
> settings to figure out the problem.
>
> It all comes down to the guy that designed the conversion came up
> with this method and there are a bunch of planes flying with it. I'm
> not tempted at this point to change it.
>
>
>
>
> [quote="mprather(at)spro.net]
>
> It's possible I don't clearly understand how you'll be wiring the
> fuel pumps and ignition system(s).. But it sounds like you are
> saying that there will be a single switch controlling everything. If
> so, I believe this switch represents a single point of failure, which
> is generally undesirable for flight critical electrical items - at
> least when it comes to switches... If the switch falls apart, the
> engine could stop running(?).
>
> Matt[/quote]
>
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Subject: | Re: Bridge Diodes use |
Eric M. Jones wrote:
> The Vf of a diode is a strongly influenced by current. A diode can be 0.7 Vf
at zero Amps, and 1.0 Vf at 10A and 1.2 Vf at 12.5. For this you have to read
the data sheet. What?! Radio Shack doesn't supply one?! Then just guess and hope
you're right. Double up on the life insurance, too.
>
>
Wow! Hyperbole and fearmongering. All in the same post.
Are you sure you don't work for those 'news" organizations that tell us
how we're killing all our children with minute traces of pesticides in
our apples? You could have a career there, you know.
You're trying to sell a product with minor improvements in areas that
don't matter. Your diode uses half the power. We get it. The only
time that would possibly mean anything is in a power out situation. In
that situation, it will be removed from the circuit with a switch. The
rest of the time, the RadioShack solution is wasting 12W of heat. That
is 0.016 horsepower [international], which will mean the difference
between hitting the trees versus warbird type climb out (NOT!). If a
system is so loaded that 12W makes a difference during normal operations
the plane won't be flying much anyway. The alternator/generator will be
constantly burning up. You state your solution doesn't weigh as much.
OK. Some guys obsess over every ounce. More power to them. If I
needed 100 of these, it might make a difference. The call out is for
exactly one in most cases. The draft in the closed hangar when I weigh
my plane will have more effect on the finish weight.
The Radio Shack rectifier has been recommended, and presumably used by
builders, for years. It has proven adequate to the tasks asked of it.
It was chosen for its price, availability, and ease of construction. If
it there had been any instance of them causing harm, financial or
physical, someone somewhere would have said something about it. Enough
with the smoke, mirrors and demagogy. You stated the benefits of your
solution. Some see validity to your claims and buy your products, just
like some people swear by mystery chemical fuel additives. Most took a
look and responded with a big "Ho-hum". To suggest at this point that a
Radio Shack rectifier would require someone to need more life insurance
in an attempt to sell more product is at best ridiculous, and at worst
downright scandalous.
Message 12
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Subject: | Re: Bridge Diodes use |
> <emjones@charter.net>
>
snip
> Yes, Matt, maybe I should have clarified some points earlier. But it was
> 100 degrees yesterday, fer chis'sakes. Thanks for your sage input.
> (Ahem...which you should have said earlier....)
>
Glad I can bust your chops a bit.. :) Stay cool...
> --------
> Eric M. Jones
> www.PerihelionDesign.com
> 113 Brentwood Drive
> Southbridge, MA 01550
> (508) 764-2072
> emjones@charter.net
>
Regards,
Matt-
Message 13
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Subject: | Creation Of Wiring Diagram |
For builders that are creating a wiring diagram, what are you using to
create it? Are you creating with pencil and paper, or have you found any
way to computerize it? Is a tool such as TurboCAD capable of creating a
large full-aircraft drawing that can then be printed out?
Dave
Message 14
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Subject: | Re: Drilling Switch holes in aluminum? |
On Wed, Jun 11, 2008 at 10:00 AM, Robert Feldtman <bobf@feldtman.com> wrote:
> wouldn't the 1/2 inch do? 15/32 is only slightly smaller, I bet it would
> work fine.
....
Actually, the S700 series switches are already a bit loose in the mfgr.'s
recommended 15/32" hole. Consequently, I would prefer to follow the vendor's
recommendation and not mount them even more loosely.
So to respond to your query, no, I don't think 1/2" holes are a good idea
for these switches.
Ron
Message 15
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Lets not beat the bridge diodes any more!!
Message 16
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Subject: | Re: Creation Of Wiring Diagram |
Dave VanLanen wrote:
> For builders that are creating a wiring diagram, what are you using to
> create it? Are you creating with pencil and paper, or have you found any
> way to computerize it? Is a tool such as TurboCAD capable of creating a
> large full-aircraft drawing that can then be printed out?
>
> Dave
>
>
I'm using Dia, an open-source diagramming tool.
Message 17
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Subject: | Re: Creation Of Wiring Diagram |
Hi Dave,
I've found TurboCAD very nice for doing electrical plans and 3D drawings
as well. It's a full featured program
that's reasonable to buy. After a life with AutoCAD and ProE, it's a
better personal solution for the individual designer.
These drawings were done in version 10, but they've been maintained thru
version 15.
http://www.macsmachine.com/images/electrical/full/primary-wiring.gif
http://www.macsmachine.com/images/largeassembly2/full/eltdwg.gif
Awesome program easy to learn............
Larry McFarland at www.macsmachine.com
Dave VanLanen wrote:
>
> For builders that are creating a wiring diagram, what are you using to
> create it? Are you creating with pencil and paper, or have you found
> any way to computerize it? Is a tool such as TurboCAD capable of
> creating a large full-aircraft drawing that can then be printed out?
>
> Dave
>
> *
> *
Message 18
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Subject: | Creation Of Wiring Diagram |
Here's a link to a great schematic tool (free) and my RV-9A wiring diagram.
I prefer to use electrical CAD toos for schematics, rather than the
mechanical CAD packages. Click to www.vx-aviation.com (link at top or scroll
to bottom of page. I have some other builders who've promised to provide me
their schematics as well-- I'll post them as I get them.
Thanks
Vern Little
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Ernest
Christley
Sent: June 11, 2008 11:54 AM
Subject: Re: AeroElectric-List: Creation Of Wiring Diagram
--> <echristley@nc.rr.com>
Dave VanLanen wrote:
> For builders that are creating a wiring diagram, what are you using to
> create it? Are you creating with pencil and paper, or have you found
> any way to computerize it? Is a tool such as TurboCAD capable of
> creating a large full-aircraft drawing that can then be printed out?
>
> Dave
>
>
I'm using Dia, an open-source diagramming tool.
Message 19
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Subject: | Re: Bridge Diodes use |
All this banter has been very interesting, but I think some people are missing
part of the point here. The power dissipation is only one issue in diodes and
the lessor important issue in my opinion. It is easy to deal with heat dissipation
with the proper heat sink. What concerns me is the voltage drop across
a normal diode. I don't to want to lose 1.2 volts if the alternative is to lose
less by using a Schotky diode that costs only pennies more. This is especially
critical if your alternator fails and you are on battery alone. This voltage
drop could be the difference between keeping things running properly and
not. Yes, you can parallel the diode with a switch as a direct E-bus feed, but
I don't want that voltage drop in normal operations either.
Just because something has worked well for years does not mean that newer products
that perform better are not available today. While the FWB is a nice package
for mounting and wiring, it is no longer the best product for the application.
If we were to continue to think this way, there would be no innovation and
we would all be running steam gauges rather than EFIS systems. In all these
discussions, I have never seen anybody make a statement that a plain diode is
the best solution, only that it is adequate. Adequate in not good enough for
me if a better solution is available. It is somewhat contradictory to install
a 21st centrury flight instument system connected to a 1950's technology power
system.
Paul Trotter
RV-8
Finishing the Wiring
----- Original Message -----
From: Ernest Christley
Subject: Re: AeroElectric-List: Re: Bridge Diodes use
>
> Eric M. Jones wrote:
> > The Vf of a diode is a strongly influenced by current. A diode
> can be 0.7 Vf at zero Amps, and 1.0 Vf at 10A and 1.2 Vf at
> 12.5. For this you have to read the data sheet. What?! Radio
> Shack doesn't supply one?! Then just guess and hope you're
> right. Double up on the life insurance, too.
> >
> >
>
> Wow! Hyperbole and fearmongering. All in the same post.
>
> Are you sure you don't work for those 'news" organizations that
> tell us
> how we're killing all our children with minute traces of
> pesticides in
> our apples? You could have a career there, you know.
>
> You're trying to sell a product with minor improvements in areas
> that
> don't matter. Your diode uses half the power. We get it. The
> only
> time that would possibly mean anything is in a power out
> situation. In
> that situation, it will be removed from the circuit with a
> switch. The
> rest of the time, the RadioShack solution is wasting 12W of
> heat. That
> is 0.016 horsepower [international], which will mean the
> difference
> between hitting the trees versus warbird type climb out (NOT!).
> If a
> system is so loaded that 12W makes a difference during normal
> operations
> the plane won't be flying much anyway. The alternator/generator
> will be
> constantly burning up. You state your solution doesn't weigh
> as much.
> OK. Some guys obsess over every ounce. More power to them.
> If I
> needed 100 of these, it might make a difference. The call out
> is for
> exactly one in most cases. The draft in the closed hangar when
> I weigh
> my plane will have more effect on the finish weight.
>
> The Radio Shack rectifier has been recommended, and presumably
> used by
> builders, for years. It has proven adequate to the tasks asked
> of it.
> It was chosen for its price, availability, and ease of
> construction. If
> it there had been any instance of them causing harm, financial
> or
> physical, someone somewhere would have said something about it.
> Enough
> with the smoke, mirrors and demagogy. You stated the benefits
> of your
> solution. Some see validity to your claims and buy your
> products, just
> like some people swear by mystery chemical fuel additives. Most
> took a
> look and responded with a big "Ho-hum". To suggest at this
> point that a
> Radio Shack rectifier would require someone to need more life
> insurance
> in an attempt to sell more product is at best ridiculous, and at
> worst
> downright scandalous.
>
>
>
>
>
>
>
>
Message 20
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Subject: | Creation Of Wiring Diagram |
When I built the RV I hand drew each of the circuits on the back of a white door
in the shop with a Sharpie pen...Easy to correct and modifiy with a solvent
rag as you go along..Its still there today and one day I may transfer it to a
more "Portable" format..One day..:)
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Ernest Christley
Sent: Wednesday, June 11, 2008 11:54 AM
Subject: Re: AeroElectric-List: Creation Of Wiring Diagram
--> <echristley@nc.rr.com>
Dave VanLanen wrote:
> For builders that are creating a wiring diagram, what are you using to
> create it? Are you creating with pencil and paper, or have you found
> any way to computerize it? Is a tool such as TurboCAD capable of
> creating a large full-aircraft drawing that can then be printed out?
>
> Dave
>
>
I'm using Dia, an open-source diagramming tool.
Message 21
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Subject: | Re: Bridge Diodes use |
I suspect that it wasn't that at all. I suspect it was just someone
writing the installation document that "understood" that diodes have
about 0.6V drop. It is quite obvious that whomever wrote this didn't
know a whole lot about ratings and power dissipation. They didn't know
that there is no such thing as a "12W" heatsink without knowing a few
more parameters.
On the other hand, kudos for trying to educate users!
Dick Tasker
Eric M. Jones wrote:
> Matt, et al.
>
> See: http://www.bandc.biz/Diode_Installation.pdf
>
> I don't claim that B & C ever stated that diodes' Vf could be summed like parallel
mosfets (etc.). But I saw the 0.6 Vf on their schematic as a very suspicious
indicator that somebody thought so, and that this should be attended to.
>
> Yes, Matt, maybe I should have clarified some points earlier. But it was 100
degrees yesterday, fer chis'sakes. Thanks for your sage input. (Ahem...which you
should have said earlier....)
>
> --------
> Eric M. Jones
> www.PerihelionDesign.com
> 113 Brentwood Drive
> Southbridge, MA 01550
> (508) 764-2072
> emjones@charter.net
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=187390#187390
>
>
>
Message 22
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Subject: | Re: Drilling Switch holes in aluminum? |
On 11 Jun 2008, at 14:38, Ron Shannon wrote:
> On Wed, Jun 11, 2008 at 10:00 AM, Robert Feldtman
> <bobf@feldtman.com> wrote:
> wouldn't the 1/2 inch do? 15/32 is only slightly smaller, I bet it
> would work fine.
> ....
>
> Actually, the S700 series switches are already a bit loose in the
> mfgr.'s recommended 15/32" hole. Consequently, I would prefer to
> follow the vendor's recommendation and not mount them even more
> loosely.
>
I used a Unibit step drill that had a 15/32 step. It did an
excellent job - the switches fit very well.
--
Kevin Horton
RV-8 (FInal Assembly)
Ottawa, Canada
http://www.kilohotel.com/rv8
Message 23
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Bob
In the information you sent on the smoke pump wiring, you showed the
ground being switched and the positive going directly to the pump.
Should the electric fuel be wired the same way?
Jonsey
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