Today's Message Index:
----------------------
1. 06:21 AM - Re: Fw: Diagnostic voltages for Alternator (Robert L. Nuckolls, III)
2. 07:19 AM - Re: Re: Multimeter problem (Robert L. Nuckolls, III)
3. 08:25 AM - Contactor Failures? (Speedy11@aol.com)
4. 08:29 AM - Re: split pin connectors (Robert L. Nuckolls, III)
5. 08:32 AM - Looking to talk to Wayne sweet (Hinde, Frank George (Corvallis))
6. 09:00 AM - EXPBUS OV Protection (revenson@comcast.net)
7. 09:37 AM - Re: EXPBUS OV Protection (Robert L. Nuckolls, III)
8. 09:42 AM - Re: Contactor Failures? (Robert L. Nuckolls, III)
9. 10:19 AM - Re: EXPBUS OV Protection (Gerry Holland)
10. 10:31 AM - Re: EXPBUS OV Protection (Bret Smith)
11. 11:01 AM - Re: PM Alternator / Regulator failure modes (Roy Wheaton)
12. 11:03 AM - Re: Multimeter problem (Eric M. Jones)
13. 11:03 AM - Alternator questions? (Paul Weismann)
14. 12:03 PM - Re: Re: PM Alternator / Regulator failure modes (Jon Goguen)
15. 02:29 PM - Re: AeroElectric-List Digest: 8 Msgs - 07/12/05 (Dave Harmon)
16. 03:54 PM - Re: Re: AeroElectric-List Digest: 8 Msgs - 07/12/05 (Charlie England)
17. 04:37 PM - Re: Re: AeroElectric-List Digest: 8 Msgs - 07/12/05 (Bruce Gray)
18. 04:53 PM - Power buss alt field breaker (plaurence@the-beach.net)
19. 05:11 PM - CESSNA SPLIT MASTER SWITCH (Travis Hamblen)
20. 07:21 PM - Re: EXPBUS OV Protection (Robert L. Nuckolls, III)
21. 07:24 PM - Re: EXPBUS OV Protection (Robert L. Nuckolls, III)
22. 07:25 PM - Re: Alternator questions? (Robert L. Nuckolls, III)
23. 07:50 PM - Re: Re: PM Alternator / Regulator failure (Robert L. Nuckolls, III)
24. 08:32 PM - Re: Power buss alt field breaker (Robert L. Nuckolls, III)
25. 08:35 PM - Re: Re: AeroElectric-List Digest: 8 Msgs - (Robert L. Nuckolls, III)
Message 1
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| Subject: | Re: Fw: Diagnostic voltages for Alternator |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 06:53 PM 7/11/2005 -0600, you wrote:
>--> AeroElectric-List message posted by: "Rick Fogerson" <rickf@cableone.net>
>
>Hi Bob,
>If you answered this already I must have missed it. Would appreciate some
>numbers as I don't have a clue what a high field voltage would be, etc.
>Rick
>----- Original Message -----
>From: Rick Fogerson
>To: aeroelectric-list@matronics.com
>Subject: Diagnostic voltages for Alternator
>
>
>Hi Bob,
>I put a jack in my airplane a la Page Z-6 for alternator diagnostics. I
>have B&C's alternator and voltage regulator. Could I get some
>numbers/ranges to the voltages for the descriptive words in the following
>paragraphs:
>
>Paragraph (a) alt output is zero when the bus voltage is ______?
Paragraph (a) says:
"(a) If the alternator field voltage is zero when the output is
zero, then the regulator or associated wiring has failed."
It's speaks simply to the fact that if you don't apply SOME
voltage to the alternator's field, then it's reasonable to
expect that even a GOOD alternator's output will be zero
because it has been commanded to shut down completely.
>Paragraph (e) If the field voltage is high_____? and does not drop
>significantly_____? when engine rpm increases but bus voltage seems
>normal under light load and sags under heavy loads....
Paragrahp (e) says:
(e) If field voltage is high, does not drop significantly when
engine RPM increases but bus voltage seems normal under
light load and sags under heavy loads, then the alternator
may have one or more diodes open/shorted.
This speaks to the situation where the alternator appears
to be operating normally some times . . . I.e. low voltage
light goes out under light loads but comes on under heavy
loads at engine RPMs sufficient for full alternator output,
then a strong field excitation voltage (close to or equal
to PRESENT bus voltage) combined with a manifestation
of inadequate alternator output (bus voltage less than
regulator setpoint and not under control of alternator) then
there is reason to suspect the alternator is crippled. The
only way you can have an alternator put out set-point
voltage under light loads but fail to support rated loads
is problems with a portion of the diode array or perhaps
one stator lead is open.
I related a first-hand experience with this phenomenon in section
3 under ALTERNATOR FAULT ISOLATION.
>What would be the voltage regulators normal set point____?
Where ever you put it or wherever it was set when you
received it. 13.8 is adequate for hi-temperature climates
while folks in Alaska might want to run it at 14.6. I believe
B&C ships them set for 14.2, most automotive products are
set at 14.2
Bob . . .
Message 2
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| Subject: | Re: Multimeter problem |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 10:39 AM 7/8/2005 -0600, you wrote:
>--> AeroElectric-List message posted by: Paul Wilson <pwilson@climber.org>
>
>Bob, Sorry to belabor this issue, but two more questions please:
>I just want a meter that tells me the battery status. Then I can put on the
>charger as needed. I thought that the table published in the Battery tender
>flyer was good enough. It says a fully changed batt (after a 12 hr rest)
>would have 12.6-12.8v and one with 12.2-12.4v would be charged at 50-75%
>based on the chemistry of the battery. Thus that 3+% is a big deal to me
>and my meters showed a spread of more than 1% and therefore I am being
>misled about my battery condition.
> I suspect my newest ~$10 GB meter is accurate, but I would like to know.
>1) Bob can you make available the gadget to test the meter discussed in
>your link below?
Sure. Check out specs on LM4040AIZ-10.0 precision regulator
at:
http://www.national.com/ds/LM/LM4040.pdf
This is a 10.000 volt zener accurate to within 10 millivolts that
sells from Digikey and others for about $2.50 See:
http://dkc3.digikey.com/PDF/T052/0592.pdf
Assemble in small box with a push-button, two 9v batteries,
a 4.7K, 1/2w resistor like shown in:
http://www.aeroelectric.com/articles/VM_Calibrator_Schm.pdf
Hook this puppy to your voltmeter to be tested
and push the button. The voltmeter should read 10.000
volts PLUS or MINUS the total error budget for the
combination of components.
For example, we know that our calibrator is off-the-shelf
rated for 10.000 plus or minus 0.01 volts. The instrument
your checking may have a specification like "plus or minus
0.5% of reading + one count". Okay lets assume a display
that shows xx.xx volts. 0.5% of 10 volts is 50 millivolts.
If we stack all errors up for a max deviation from true,
we get 10 millivolts for the calibrator, 50 millivolts for
the instrument plus another 10 millivolts for the display
error for a total uncertainty of 60 millivolts IN EITHER
DIRECTION.
Probability is that it's less . . . with most instruments
having less than 1/2 the maximum error . . . but one
cannot DEPEND on it for all cases.
So, any reading between 10.06 and 9.94 volts says that
none of the pieces of equipment (calibrator, voltmeter
or display) are suspected of being out of stated
tolerance.
Now, you can use a calibrator to wash out some
instrument error. Suppose we got a reading of 10.04
volts. We can attribute a maximum of 0.01 volts to
calibrator error and another 0.01 volts to display
error which says are degree of uncertainty for the
reading is reduced to 0.02 volts. Therefore, the
REAL voltage reading is somewhere between 10.02 and
10.06 volts.
This resolves to an error of 0.2% of reading so
your observations of battery voltage in the 12.5
volt have a degree of uncertainty around plus or
minus 0.025 volts.
Many 5 digit displays have a tighter tolerance in
voltmeter readings but higher display errors. For
example, one of my 5 digit instruments is 0.1% plus
or minus 5 counts.
In this case the error for this instrument to read
my 10.000 calibrator would be 10.000 plus or minus
.025 volts (10 mv for calibrator, 10 mv for voltmeter,
and 5 counts for display).
You can wash out error in your calibrator by having
it checked against an instrument of still greater
accuracy. For example, if you know that the calibrator
puts out 10.008 volts (at room temperature) you can
account for this in your new error budget for
deducing the accuracy of your own instruments.
Do not assume that putting your own portable instrument
on a super accurate source can wash out more than
voltmeter error. The "counts" error in the display
is a digital quantizing error that may or may not
be fixed. In the case of my xx.xxx reading instrument,
I'll ALWAYS have a degree of uncertainty of plus or
minus 0.005 volts irrespective of other factors.
Bob . . .
Message 3
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| Subject: | Contactor Failures? |
--> AeroElectric-List message posted by: Speedy11@aol.com
Bob,
In yesterdays post, you said;
Battery terminal breakage (or battery contactor failure) is
relatively rare. I've never encountered one personally or known
one who has. I've replaced dozens of contactors that failed in
pre-flight but never one that failed in flight.
What kinds of failures have you seen? Failure due to heat? manufacturing
defects? external damage? internal failure?
Is it worthwhile to replace contactors periodically similar to your battery
replacement concept? If so, how often?
Stan Sutterfield
Message 4
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| Subject: | Re: split pin connectors |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 08:56 PM 7/12/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: <bakerocb@cox.net>
>
>7/12/2005
>
>OC, please pass on to Bob Nuckolls.
>
>A total of seven "split pin connectors" emanating from the autopilot, all
>blue in color were found behind the instrument panel of the Beech Sierra,
>Each one was first disconnected and then reconnected. No further trouble
>shooting took place before an operational test was conducted on the Century
>IIB autopilot. The test on the ground was successful, A subsequent airborne
>operational test also proved the autopilot to be fully operational.
>
>Thank you again for any time, effort and thought that went into this trouble
>shooting. George Philipps
I'll call the service reps in piston props and see if I
can get a better reading on what these connectors are.
Bob . . .
Message 5
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| Subject: | Looking to talk to Wayne sweet |
--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
Wayne are you on this list?.....Can you contact me at
frank.hinde@hp.com...Thanks and don't worry you don't owe me money...:)
Frank
Do not archive
Message 6
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| Subject: | EXPBUS OV Protection |
1.25 RCVD_NUMERIC_HELO Received: contains an IP address used for HELO
--> AeroElectric-List message posted by: revenson@comcast.net
Haven't found any comments in the archives on the alternator OV Protection feature
built into the EXPBUS. Has any review been done here?
Haven't found any comments in the archiveson thealternator OV Protection feature
built into the EXPBUS. Has any review been done here?
Message 7
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| Subject: | Re: EXPBUS OV Protection |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 03:56 PM 7/13/2005 +0000, you wrote:
>--> AeroElectric-List message posted by: revenson@comcast.net
>
>Haven't found any comments in the archives on the alternator OV Protection
>feature built into the EXPBUS. Has any review been done here?
>
>Haven't found any comments in the archiveson thealternator OV Protection
>feature built into the EXPBUS. Has any review been done here?
>
An accurate review requires detailed schematics and parts
lists of the proffered system. I've not seen the necessary
documentation . . . is it posted on the 'net?
Bob . . .
Message 8
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| Subject: | Re: Contactor Failures? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 11:21 AM 7/13/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: Speedy11@aol.com
>
>Bob,
>In yesterdays post, you said;
> Battery terminal breakage (or battery contactor failure) is
> relatively rare. I've never encountered one personally or known
> one who has. I've replaced dozens of contactors that failed in
> pre-flight but never one that failed in flight.
>What kinds of failures have you seen? Failure due to heat? manufacturing
>defects? external damage? internal failure?
Internal failure usually attributable to wear out.
Corroded/burned contacts resulting in high resistance
across the closed contacts.
>Is it worthwhile to replace contactors periodically similar to your battery
>replacement concept? If so, how often?
Depends on what you consider to be a reasonable insurance
premium. If you don't mind a $25 "investment" every
1, 2, 3 years or 200, 500, 1000 hours, then pick your numbers
and fly with whatever degree of comfort this activity
affords you. I try to design so that contactor failure does
not force an uncomfortable in-flight scenario. Under this
design philosophy, it seems to me that the "insurance" premium
is a poor value and the contactor(s) can be operated to
wear-out.
Bob . . .
Message 9
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| Subject: | Re: EXPBUS OV Protection |
--> AeroElectric-List message posted by: Gerry Holland <gholland@gemini-resourcing.com>
Bob Hi!
Some information that may or may not allow you to make comment on EXP Bus OV
Protection.
http://support.anywheremap.com/pdfs/expbus_overvolt.pdf
http://support.anywheremap.com/pdfs/exp2vsch.PDF
Regards
Gerry
How much free photo storage do you get? Store your holiday
Message 10
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| Subject: | Re: EXPBUS OV Protection |
--> AeroElectric-List message posted by: "Bret Smith" <smithhb@tds.net>
Bob, you might get what you need here...
http://support.anywheremap.com/idx/0/020/article/Avionics_Documentation_and_Reference_Materials.html
Bret Smith
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
Subject: Re: AeroElectric-List: EXPBUS OV Protection
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<nuckollsr@cox.net>
>
> At 03:56 PM 7/13/2005 +0000, you wrote:
>
> >--> AeroElectric-List message posted by: revenson@comcast.net
> >
> >Haven't found any comments in the archives on the alternator OV
Protection
> >feature built into the EXPBUS. Has any review been done here?
> >
> >Haven't found any comments in the archiveson thealternator OV Protection
> >feature built into the EXPBUS. Has any review been done here?
> >
>
> An accurate review requires detailed schematics and parts
> lists of the proffered system. I've not seen the necessary
> documentation . . . is it posted on the 'net?
>
> Bob . . .
>
>
Message 11
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| Subject: | Re: PM Alternator / Regulator failure modes |
--> AeroElectric-List message posted by: Roy Wheaton <roy_wheaton@yahoo.com>
Many motorcycle manufacturers (Harley, Indian, etc.) still use PM-type of
alternators and 2 or 3 phase regulators. The failures are most often an open or
shorted rectifier diode, or a shorted SCR. There are usually two SCR's in
parallel, and it's rare for both to fail.
Message 12
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| Subject: | Re: Multimeter problem |
--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
Various meter concerns continue to pop up here, but I would like to advise
that these are unjustified.
In the days of analog meters people never worried because the resolution was
so poor. Now that you can see the last digit, one is inclined to worry. Of
course, we worry about the easy stuff--nobody worries about the strength of
their weld joints or fiberglass structure.
By the Way--holding as some sort of "standards" the venerable Simpson 260
(Simpson still makes these!) or the Weston Master II light meter, or your HP
200AB Oscillator---Well, my grandmother (who had not one nostalgic bone in
her body) would say bad things in Finnish at you. We never knew what she was
saying but when she said them, spit would fly all the animals would scatter
.
It's pretty easy to set up your own tests to determine if your meter is
accurate...then you will discover that there are no calibration adjustments
anyway! You can eliminate most consideration by looking and smelling
carefully for burned resistors in the meter.
Heck, I suggest if you are unhappy with the accuracy of your meters--donate
them to me!
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
"Everything you've learned in school as "obvious" becomes
less and less obvious as you begin to study the universe.
For example, there are no solids in the universe. There's
not even a suggestion of a solid. There are no absolute con-
tinuums. There are no surfaces. There are no straight lines."
- R. Buckminster Fuller
Message 13
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| Subject: | Alternator questions? |
--> AeroElectric-List message posted by: "Paul Weismann" <pw@weismannassociates.com>
Apologies if this topic has been covered but I searched and could not
find...
2 alternator questions:
1. I am using a Denso automotive alternator in my turbine Rotorway
helicopter. The generally used diagram for the alternator is to have
TWO AWG12 b-leads running each to its own 30amp CB, and then TWO AWG12
leads to a junction post linking the battery and starter. I was going
to use the post on the starter for this.
What is the benefit, if any, to using 2 wires - is it only
redundancy, and if so, how much incremental protection would such a
design offer?
2. In some of Bingelis' writings, he recommends having the alternator
b-leads shielded. I do not see shielding in Bob's schematics (apologies
if I am reading them incorrectly). Is it necessary?
Thanks, very informative resource.
Paul
Message 14
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| Subject: | Re: PM Alternator / Regulator failure modes |
--> AeroElectric-List message posted by: Jon Goguen <jon.goguen@umassmed.edu>
On Jul 13, 2005, at 1:57 PM, Roy Wheaton wrote:
> The failures are most often an open or
> shorted rectifier diode, or a shorted SCR. There are usually two SCR's
> in
> parallel, and it's rare for both to fail.
Am I correct in thinking that none of these failure modes would result
in an over voltage condition?
Thanks!
Jon
Jon Goguen
jon.goguen@umassmed.edu
Central Massachusetts
Kitfox Series V Rotax 912S / N456JG (reserved)
Complete except for electrics and avionics
Message 15
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| Subject: | Re: AeroElectric-List Digest: 8 Msgs - 07/12/05 |
"AeroElectric-List Digest List" <aeroelectric-list-digest@matronics.com>
--> AeroElectric-List message posted by: "Dave Harmon" <vagabondpa15@verizon.net>
Thanks every body I now have a better understanding on internal voltage
regulation. Do you think a dry contactor on the B+ terminal will act fast
enough? What's your thoughts on a fusible link on the output (B+) lead and
go directly to the battery. PS I don't have a lot of money in the radios but
every nickel counts to me. I think that's what got me into this problem I
bought a 90.00 denso 40 amp. min. Now I don't want to use it. Maybe I can
takeout the reg. and go external.
Dave
----- Original Message -----
From: "AeroElectric-List Digest Server"
<aeroelectric-list-digest@matronics.com>
Subject: AeroElectric-List Digest: 8 Msgs - 07/12/05
> *
>
> ==================================================
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>
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>
> AeroElectric-List Digest Archive
> ---
> Total Messages Posted Tue 07/12/05: 8
>
>
> Today's Message Index:
> ----------------------
>
> 1. 06:48 AM - Re: Alternator output (Robert L. Nuckolls, III)
> 2. 07:07 AM - Re: AeroElectric-List Digest: 11 Msgs - 07/11/05 (Dave
> Harmon)
> 3. 08:16 AM - Internal regulation (Kevin Horton)
> 4. 08:58 AM - Re: Internal regulation (Hinde, Frank George
> (Corvallis))
> 5. 09:20 AM - Re: AeroElectric-List Digest: 11 Msgs - 07/11/05
> (Glaeser, Dennis A)
> 6. 09:53 AM - Re: Internal regulation (Phil Birkelbach)
> 7. 05:57 PM - split pin connectors ()
> 8. 06:21 PM - Re: ICOM PTT ()
>
>
> ________________________________ Message 1
> _____________________________________
>
>
> Time: 06:48:40 AM PST US
> From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
> Subject: Re: AeroElectric-List: Alternator output
>
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <nuckollsr@cox.net>
>
> At 09:04 AM 7/8/2005 -0500, you wrote:
>
>>--> AeroElectric-List message posted by: "Vern W." <vernw@ev1.net>
>>
>> I'd like to ask a simple follow-up question here, Bob.
>> In a scenario of Z13/8 with only the one main battery existing in the
>>system, if (for example) a lug breaks on the battery and it's taken out of
>>the system, will the main alternator continue to power the system? Or
>>without the battery in the system, would there be a voltage runaway and
>>the
>>main alternator would have to be taken offline? ... (If that were the
>>case,
>>then the SD8 would have no chance of coming alive by itself).
>> If the main alternator WOULD continue to power the system within the
>>proper voltage range (due to it's regulator controlling the voltage?), and
>>the SD8 is then switched on, would the SD8 come alive using the voltage
>>from
>>the main alternator as the exciter? And then would the SD8 continue to
>>power
>>the system on it's own without a battery in the system?
>> What I'm trying to get straight in my head is the various failure
>>scenarios possible and how the "surviving" components are expected to
>>react.
>
> A worthwhile endeavor. Most alternators will continue to produce
> power with a disconnected battery as long as they don't get "stalled".
> A wound field alternator needs a sample of it's own output to produce
> power . . . load it severely (in excess of it's ratings) just for
> a few milliseconds and it may quit and stay dead.
>
> Battery terminal breakage (or battery contactor failure) is
> relatively rare. I've never encountered one personally or known
> one who has. I've replaced dozens of contactors that failed in
> pre-flight but never one that failed in flight.
>
> Is the risk zero? No, just small. If this worries you, then
> perhaps a dual battery installation is in order either in the
> form of Z-30 implementation or perhaps Z-14. Keep in mind that
> hundreds of thousands of spam cans have flown for nearly
> a century with electrical systems being WAAAAYYYY down on the
> list of contributing events for the entire constellation of
> accident scenarios.
>
> When I walk up to a rental airplane and make ready to launch,
> I don't care if ANYTHING on the panel is getting power. I have
> tools in my flight back and the mindset that I intend to arrive
> at the airport of original destination with the airplane in
> a "J-3 Mode" of operation if necessary.
>
> I'll suggest it's much easier to prepare yourself for the
> worst kinds of electrical failure than it is to design a system that
> will NEVER fail. The worst case is that your "bullet proof"
> system will fail you anyhow and you'll find yourself ill-prepared
> to cope with it.
>
> What kind of airplane are you building? How is it electrically
> dependent? How do you plan to use the airplane? How much are
> YOU electrically dependent? The road to comfortable flight
> is lined with answers to these questions even if some answers
> do not offer 99.999999 or even 90.0 percent reliability.
>
> Bob . . .
>
>
> ________________________________ Message 2
> _____________________________________
>
>
> Time: 07:07:23 AM PST US
> From: "Dave Harmon" <vagabondpa15@verizon.net>
> Subject: AeroElectric-List: Re: AeroElectric-List Digest: 11 Msgs -
> 07/11/05
> "AeroElectric-List Digest List"
> <aeroelectric-list-digest@matronics.com>
>
> --> AeroElectric-List message posted by: "Dave Harmon"
> <vagabondpa15@verizon.net>
>
> Can we go over again why it's not rec. to use internal regulation on
> alternators.
> Dave
> ----- Original Message -----
> From: "AeroElectric-List Digest Server"
> <aeroelectric-list-digest@matronics.com>
> Subject: AeroElectric-List Digest: 11 Msgs - 07/11/05
>
>
>> *
>>
>> ==================================================
>> Online Versions of Today's List Digest Archive
>> ==================================================
>>
>> Today's complete AeroElectric-List Digest can also be found in either of
>> the
>> two Web Links listed below. The .html file includes the Digest formatted
>> in HTML for viewing with a web browser and features Hyperlinked Indexes
>> and Message Navigation. The .txt file includes the plain ASCII version
>> of the AeroElectric-List Digest and can be viewed with a generic text
>> editor
>> such as Notepad or with a web browser.
>>
>> HTML Version:
>>
>>
>> http://www.matronics.com/digest/aeroelectric-list/Digest.AeroElectric-List.2005-07-11.html
>>
>> Text Version:
>>
>>
>> http://www.matronics.com/digest/aeroelectric-list/Digest.AeroElectric-List.2005-07-11.txt
>>
>>
>> ================================================
>> EMail Version of Today's List Digest Archive
>> ================================================
>>
>>
>> AeroElectric-List Digest Archive
>> ---
>> Total Messages Posted Mon 07/11/05: 11
>>
>>
>> Today's Message Index:
>> ----------------------
>>
>> 1. 05:57 AM - Diodes 101 (Lui Esc)
>> 2. 06:33 AM - Re: Split Pin Connectors? ()
>> 3. 07:14 AM - Re: Diodes 101 (chad-c_sip@stanfordalumni.org)
>> 4. 07:14 AM - Re: Diodes 101 (Robert L. Nuckolls, III)
>> 5. 07:19 AM - Re: Z13 with B&C Alt/Reg combination ? (Robert L.
>> Nuckolls, III)
>> 6. 08:33 AM - Re: Re: Help - low voltage - update (Robert L.
>> Nuckolls, III)
>> 7. 08:35 AM - Re: Help - low voltage - update (P.S.) (Robert L.
>> Nuckolls, III)
>> 8. 09:04 AM - Re: alternator testing (Mark & Lisa)
>> 9. 09:06 AM - Re: 24V Starter (Mark & Lisa)
>> 10. 09:32 AM - Overvoltage and PM alternators (Jon Goguen)
>> 11. 05:54 PM - Fw: Diagnostic voltages for Alternator (Rick Fogerson)
>>
>>
>> ________________________________ Message 1
>> _____________________________________
>>
>>
>> Time: 05:57:58 AM PST US
>> From: "Lui Esc" <f1rocketbuilder@hotmail.com>
>> Subject: AeroElectric-List: Diodes 101
>>
>> --> AeroElectric-List message posted by: "Lui Esc"
>> <f1rocketbuilder@hotmail.com>
>>
>> Does anyone knows if there is any document that covers Diodes by
>> themselves?
>> I have a few gray areas understanding which diode to use, identify,
>> rating,
>> etc.
>>
>> There are several diodes shown on the Aeroelectric diagrams but I can't
>> see
>> part numbers to reference. Ex. a diode between the essential bus and the
>> primary bus, also, diode on the starter seleniod.
>>
>> I need to use some diodes in other areas but, I am still learning and
>> want
>> to be sure I use/order the correct stuff.
>>
>> I sent an email to Bob via his web site, but I did not hear back from
>> him.
>> I just learned about this forum, so I subscribed to the Digest.
>>
>> Thanks,
>> LE
>>
>>
>> Comments/Questions: Building a F-1 Rocket. Love your publications,
>> learned
>> a lot thanks to you. But continue trying to learn and understand the
>> electric side as much as I can since I am doing the wiring by myself.
>> Do
>> you have a document that covers Diodes by themselves? I have a gray area
>> trying to identify part number or diode required on certain areas
>> mentioned
>> in your publications. Ex. a diode between the essential bus and the
>> primary
>> bus and others. Thanks. Luis
>>
>>
>> ________________________________ Message 2
>> _____________________________________
>>
>>
>> Time: 06:33:02 AM PST US
>> From: <bakerocb@cox.net>
>> Subject: AeroElectric-List: Re: Split Pin Connectors?
>>
>> --> AeroElectric-List message posted by: <bakerocb@cox.net>
>>
>> Aeroelectric-list message previously posted by Bob Nuckolls
>>
>> <<....skip....What's the brand and model number of the autopilot?
>> One can often deduce the connector technology by knowing
>> who made the system. Manufacturers often have a stable
>> of connectors-of-choice. Getting a peek at the installation/
>> maintenance manual for the autopilot may help. Was the
>> autopilot installed as a Beechcraft option? If so, I
>> may have access to data in the company archives that
>> would help. Bob . . .>>
>>
>> 7/1/2005
>>
>> Hello Bob Nuckolls, I am the owner of the Beechcraft Sierra with
>> autopilot
>> problems that OC Baker referred to . In answer to your response I can
>> provide the following additional data, and any help/suggestions you
>> provide
>> would be greatly appreciated.
>>
>> The POH for the Beechcraft Sierra C24R depicts an autopilot in the
>> instrument panes for all a/c after serial no. MC 571. My a/c, serial no.
>> is
>> MC 778 mfg'd in 1982. However, the POH does not provide any information
>> on
>> the autopilot itself. Neither the logs nor the weight and balance sheets
>> mention an autopilot add-on. I therefore am led to believe that it was a
>> factory install at time of delivery. The autopilot itself is a Century
>> IIB
>> mfg'd by Flight Systems, Inc. PO Box 610, Mineral Wells, TX 76067. As to
>> "split pin connectors", another Sierra owner offers that the techie was
>> referring to the "Little Blue Plugs used by Century for many of their
>> autopilot connections. They have stamped receptor pins rather than solid
>> ones."
>>
>> Does any of this additional info help shed some light on the problem?
>> Thanks
>> for you help. George Philipps
>>
>>
>> ________________________________ Message 3
>> _____________________________________
>>
>>
>> Time: 07:14:15 AM PST US
>> From: chad-c_sip@stanfordalumni.org
>> Subject: Re: AeroElectric-List: Diodes 101
>> Z-USANET-MsgId: XID223JgkoNs0424X37
>>
>> --> AeroElectric-List message posted by: chad-c_sip@stanfordalumni.org
>>
>> A good ol' Google Search on "diode tutorial" brought up this link:
>>
>> http://www.americanmicrosemi.com/tutorials/diode.htm
>>
>> It seemed like a good introduction. At least from that you know the
>> terminology used when describing a diode. And now you can compare the
>> performance of different beasties. The only other thing I'd add is that
>> "full
>> wave rectifiers" are really just 4 diodes laid out nose-to-tail in a
>> diamond
>> pattern. We tend to talk about rectifiers as power diodes are they
>> already
>> come in larger power packages ready to be attached to a heat sink. And
>> there's
>> no reason you can't simply use only one of the 4 diodes in the package.
>>
>> Good luck.
>>
>> Chad
>>
>> Chad Sipperley
>> Lancair IV-P turbine (under construction)
>> Phoenix, AZ
>>
>> ------ Original Message ------
>> From: "Lui Esc" <f1rocketbuilder@hotmail.com>
>> Subject: AeroElectric-List: Diodes 101
>>
>>> --> AeroElectric-List message posted by: "Lui Esc"
>> <f1rocketbuilder@hotmail.com>
>>>
>>> Does anyone knows if there is any document that covers Diodes by
>> themselves?
>>> I have a few gray areas understanding which diode to use, identify,
>>> rating,
>>
>>> etc.
>>>
>>> There are several diodes shown on the Aeroelectric diagrams but I can't
>>> see
>>
>>> part numbers to reference. Ex. a diode between the essential bus and
>>> the
>>> primary bus, also, diode on the starter seleniod.
>>>
>>> I need to use some diodes in other areas but, I am still learning and
>>> want
>>> to be sure I use/order the correct stuff.
>>>
>>> I sent an email to Bob via his web site, but I did not hear back from
>>> him.
>>
>>> I just learned about this forum, so I subscribed to the Digest.
>>>
>>> Thanks,
>>> LE
>>>
>>>
>>> Comments/Questions: Building a F-1 Rocket. Love your publications,
>>> learned
>>
>>> a lot thanks to you. But continue trying to learn and understand the
>>> electric side as much as I can since I am doing the wiring by myself.
>>> Do
>>> you have a document that covers Diodes by themselves? I have a gray
>>> area
>>> trying to identify part number or diode required on certain areas
>>> mentioned
>>
>>> in your publications. Ex. a diode between the essential bus and the
>>> primary
>>
>>> bus and others. Thanks. Luis
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>> ________________________________ Message 4
>> _____________________________________
>>
>>
>> Time: 07:14:15 AM PST US
>> From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>> Subject: Re: AeroElectric-List: Diodes 101
>>
>> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>> <nuckollsr@cox.net>
>>
>> At 07:56 AM 7/11/2005 -0500, you wrote:
>>
>>>--> AeroElectric-List message posted by: "Lui Esc"
>>><f1rocketbuilder@hotmail.com>
>>>
>>>Does anyone knows if there is any document that covers Diodes by
>>>themselves?
>>>I have a few gray areas understanding which diode to use, identify,
>>>rating,
>>>etc.
>>>
>>>There are several diodes shown on the Aeroelectric diagrams but I can't
>>>see
>>>part numbers to reference. Ex. a diode between the essential bus and the
>>>primary bus, also, diode on the starter seleniod.
>>>
>>>I need to use some diodes in other areas but, I am still learning and
>>>want
>>>to be sure I use/order the correct stuff.
>>>
>>>I sent an email to Bob via his web site, but I did not hear back from
>>>him.
>>>I just learned about this forum, so I subscribed to the Digest.
>>
>> ANY rectifier diode that LOOKs like this will do:
>>
>> http://www.aeroelectric.com/Pictures/s401-25.jpg
>>
>> Here's an excerpt from the Radio Shack catalog:
>>
>> http://www.aeroelectric.com/Pictures/RS_Diodes.jpg
>>
>> Note that it offers an 276-1185 full wave bridge rectifier
>> which is suited for use as the e-bus normal feed diode illustrated
>> above
>>
>> It also offers the 1N540X series diodes which
>> are my favorites for use on contactors. These are
>> mechanically more robust and easy to work with.
>>
>> See:
>>
>> http://www.aeroelectric.com/Pictures/s701-1l.jpg
>> http://www.aeroelectric.com/Pictures/s701-2.jpg
>>
>> If the 5400 series are too heavy mechanically
>> for your application, consider the 1N400x series
>> on the same page.
>>
>> A typical useage for the 4000 series is shown
>> here:
>>
>> http://www.aeroelectric.com/Pictures/s704inst.jpg
>>
>> Ratings for diodes used as spike catchers is
>> not critical. Only the e-bus normal feed diode
>> needs to have some electrical heftiness and
>> the 276-1185 or any of its siblings will be fine.
>> If it comes in this package, then it's big enough.
>>
>> See note 12 of
>>
>> http://aeroelectric.com/articles/Rev11/AppZ_R11C.pdf
>>
>> and
>>
>> http://aeroelectric.com/articles/spikecatcher.pdf
>>
>> Bob . . .
>>
>>
>> ________________________________ Message 5
>> _____________________________________
>>
>>
>> Time: 07:19:17 AM PST US
>> From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>> Subject: Re: AeroElectric-List: Z13 with B&C Alt/Reg combination ?
>>
>> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>> <nuckollsr@cox.net>
>>
>> At 10:35 PM 7/10/2005 -0500, you wrote:
>>
>>>--> AeroElectric-List message posted by: "Bill Schlatterer"
>>><billschlatterer@sbcglobal.net>
>>>
>>>
>>>Bob, am I missing something? I was looking for the Z13 diagram with the
>>>B&C
>>>alt/reg combination and can't seem to find it. Would be great to see
>>>with
>>>P-mag but assume you can just add in the R11C Z13 w/P-Mags.
>>>
>>>Bill S
>>>RV7a Arkansas
>>
>> The z-figures are crafted to illustrate architectures, not to make
>> specific recommendations for use of parts. I COULD craft a dozen
>> z-13's, each depicting a different regulator, alternator, etc.
>>
>> Usage of the LR-3 series devices is illustrated in several
>> other z-figures . . . if that's your regulator of choice for
>> Z-13, then you'll need to draw out your own power distribution
>> diagram modified to include your features of choice.
>>
>> EVERYONE should do their own power distribution diagrams to
>> exactly match their project. The Z-figures are only a guide to
>> get you started.
>>
>> Bob . . .
>>
>>
>> ________________________________ Message 6
>> _____________________________________
>>
>>
>> Time: 08:33:48 AM PST US
>> From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>> Subject: Re: AeroElectric-List: Re: Help - low voltage - update
>>
>> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>> <nuckollsr@cox.net>
>>
>> Before you pull anything off the airplane, let's do a good job of
>> diagnosis to KNOW which part needs attention. I've got a piece nearly
>> finished on alternator system troubleshooting that I'll publish on
>> the website in next day or so along with links from this list.
>>
>> Bob . . .
>>
>> At 06:38 AM 7/9/2005 -0400, you wrote:
>>
>>>--> AeroElectric-List message posted by: "Mike & Lee Anne Wiebe"
>>><mwiebe@sympatico.ca>
>>>
>>>Thx Jim - that makes some sense. I think it's time to pull the
>>>alternator and check the diode bridge.
>>>
>>>You raise another interesting idea. What do you think of this scenario?
>>>I recently changed the battery to a smaller one (had the Odessey 680
>>>ready to go for the new aircraft, so when it came time for a
>>>"Knuckoll's change-out" I replaced the large B&C with the Odessey). The
>>>alternator is the larger B&C, so alternator load shouldn't be the
>>>problem (presuming the diodes are OK). Do you think a change to a
>>>smaller battery might have changed the ability of the system to "sink"
>>>the pulsing load of the strobes, and make voltage vary more?
>>>
>>>I guess it's also possible that its done this since new, and I've just
>>>never noticed. Though somehow I think I would have before now.
>>>
>>>Mike
>>>
>>>
>>>--
>>>
>>>
>>>-- incoming mail is certified Virus Free.
>>
>>
>> Bob . . .
>>
>>
>> --------------------------------------------------------
>> < Throughout history, poverty is the normal condition >
>> < of man. Advances which permit this norm to be >
>> < exceeded -- here and there, now and then -- are the >
>> < work of an extremely small minority, frequently >
>> < despised, often condemned, and almost always opposed >
>> < by all right-thinking people. Whenever this tiny >
>> < minority is kept from creating, or (as sometimes >
>> < happens) is driven out of a society, the people >
>> < then slip back into abject poverty. >
>> < >
>> < This is known as "bad luck". >
>> < -Lazarus Long- >
>> <------------------------------------------------------>
>> http://www.aeroelectric.com
>>
>>
>> ________________________________ Message 7
>> _____________________________________
>>
>>
>> Time: 08:35:20 AM PST US
>> From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>> Subject: AeroElectric-List: Re: Help - low voltage - update (P.S.)
>>
>> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>> <nuckollsr@cox.net>
>>
>> PS have you conducted the tests described in:
>>
>> http://www.aeroelectric.com/articles/Alternators/Alternator_Test.pdf
>>
>> This is the best way to isolate the problem with respect to
>> regulation or alternator issues . . .
>>
>> B-
>>
>> Before you pull anything off the airplane, let's do a good job of
>> diagnosis to KNOW which part needs attention. I've got a piece nearly
>> finished on alternator system troubleshooting that I'll publish on
>> the website in next day or so along with links from this list.
>>
>> Bob . . .
>>
>>
>> ________________________________ Message 8
>> _____________________________________
>>
>>
>> Time: 09:04:07 AM PST US
>> From: "Mark & Lisa" <marknlisa@hometel.com>
>> Subject: Re: AeroElectric-List: alternator testing
>>
>> --> AeroElectric-List message posted by: "Mark & Lisa"
>> <marknlisa@hometel.com>
>>
>> Bob,
>>
>> Thanks again!
>>
>> Mark & Lisa Sletten
>> Legacy FG N828LM
>> http://www.legacyfgbuilder.com
>>
>> DO NOT ARCHIVE
>>
>>
>> ________________________________ Message 9
>> _____________________________________
>>
>>
>> Time: 09:06:32 AM PST US
>> From: "Mark & Lisa" <marknlisa@hometel.com>
>> Subject: Re: AeroElectric-List: 24V Starter
>>
>> --> AeroElectric-List message posted by: "Mark & Lisa"
>> <marknlisa@hometel.com>
>>
>> Jim,
>>
>> Thank you too!
>>
>> Mark & Lisa Sletten
>> Legacy FG N828LM
>> http://www.legacyfgbuilder.com
>>
>> DO NOT ARCHIVE
>>
>>
>> ________________________________ Message 10
>> ____________________________________
>>
>>
>> Time: 09:32:25 AM PST US
>> From: Jon Goguen <jon.goguen@umassmed.edu>
>> Subject: AeroElectric-List: Overvoltage and PM alternators
>>
>> --> AeroElectric-List message posted by: Jon Goguen
>> <jon.goguen@umassmed.edu>
>>
>> Hi All,
>>
>> My first post to the list. I'm co-builder of the Kitfox described in
>> the signature along with my uncle Nelson Goguen. Most of what remains
>> to get the ship finished is electrical so here I am. I've read Bob's
>> Aeroeletric Connection and found it very informative, and very much
>> like his design philosophy and the principle that we should build
>> better than certified. I've had a lifelong interest in electronics
>> and instrumentation, and hope I might be able to make some useful
>> contributions to the community. Thanks in advance for all your relies.
>>
>> Now down to business. I'm wondering about the importance of
>> overvoltage protection on PM alternators. Without a field coil,
>> extreme voltage runaway shouldn't be possible with these machines.
>> They do produce 30 volts or so, which could certainly be damaging if it
>> passed through the regulator, but I believe the regulators use a phase
>> control shunt-based design. If so, the shunting SCRs would virtually
>> always fail in the conducting mode, which would give low rather than
>> high voltage output. Does anyone know of a documented case of
>> overvoltage problems with a properly installed PM alternator?
>>
>> Given the simplicity and reliability of PM alternators, it would seem
>> that the regulator is by far the weakest link in the charging system.
>> This would argue for a dual regulator design. I don't know enough
>> about the regulator innards to know if paralleling two of them would
>> result in undesirable interactions, but I suspect that it might. This
>> could be avoided by simply providing means to switch between the two
>> regulators.
>>
>> So:
>>
>> Does OV protection really make sense for a PM alternator system?
>>
>> Would a dual-regulator design provide a worthwhile enhancement in
>> reliability?
>>
>> Thanks!
>>
>> Jon
>>
>> Jon Goguen
>> jon.goguen@umassmed.edu
>> Central Massachusetts
>> Kitfox Series V Rotax 912S / N456JG (reserved)
>> Complete except for electrics and avionics
>>
>>
>> ________________________________ Message 11
>> ____________________________________
>>
>>
>> Time: 05:54:23 PM PST US
>> From: "Rick Fogerson" <rickf@cableone.net>
>> Subject: AeroElectric-List: Fw: Diagnostic voltages for Alternator
>>
>> --> AeroElectric-List message posted by: "Rick Fogerson"
>> <rickf@cableone.net>
>>
>> Hi Bob,
>> If you answered this already I must have missed it. Would appreciate
>> some
>> numbers
>> as I don't have a clue what a high field voltage would be, etc.
>> Rick
>> ----- Original Message -----
>> From: Rick Fogerson
>> Subject: Diagnostic voltages for Alternator
>>
>>
>> Hi Bob,
>> I put a jack in my airplane a la Page Z-6 for alternator diagnostics. I
>> have B&C's
>> alternator and voltage regulator. Could I get some numbers/ranges to the
>> voltages for the descriptive words in the following paragraphs:
>>
>> Paragraph (a) alt output is zero when the bus voltage is ______?
>>
>> Paragraph (e) If the field voltage is high_____? and does not drop
>> significantly_____?
>> when engine rpm increases but bus voltage seems normal under light load
>> and sags under heavy loads....
>>
>> What would be the voltage regulators normal set point____?
>>
>>
>> Thanks Bob and have a great 4th of July,
>> Rick Fogerson
>> RV3 done, making POH
>> Boise, ID
>>
>>
>>
>
>
> ________________________________ Message 3
> _____________________________________
>
>
> Time: 08:16:50 AM PST US
> From: Kevin Horton <khorton01@rogers.com>
> Subject: AeroElectric-List: Internal regulation
>
> --> AeroElectric-List message posted by: Kevin Horton
> <khorton01@rogers.com>
>
> On 12 Jul 2005, at 10:06, Dave Harmon wrote:
>
>> --> AeroElectric-List message posted by: "Dave Harmon"
>> <vagabondpa15@verizon.net>
>>
>> Can we go over again why it's not rec. to use internal regulation on
>> alternators.
>> Dave
>
>
> Dave,
>
> The first big question is whether you want to have over voltage
> protection or not. Some folks who have never heard of any over
> voltage cases on cars, figure that an automotive alternator with
> internal regulation is reliable enough that they don't worry about an
> over voltage. But, there was a message on this list a while back
> from a guy who had an automotive alternator on his aircraft that
> would go into an over voltage condition as soon as he selected it
> on. So, over voltages do happen.
>
> If your avionics are cheap, or you have enough money that you are
> prepared to risk them, you could go without over voltage protection.
>
> If you want over voltage protection, and you use an externally
> regulated alternator, the over voltage protection device can simply
> cut the power between the voltage regulator and the alternator
> field. This line only has small current in it, so there is no
> problem to chop the power if an over voltage ever occurs.
>
> But, if you have an internally regulated alternator, the wire from
> the voltage regulator to the field is buried inside the alternator -
> you can't get at it. So, the only way to deal with an over voltage
> is to have a contactor in the alternator output that is opened
> automatically if the alternator runs away. This contactor will have
> to open when the alternator is supplying as much current as it can
> possibly do, and there is some question about whether the contactor
> will actually reliably cut the alternator output, or whether it might
> arc internally and weld closed.
>
> There have also been a few unexplained problems with internally
> regulated alternators sold by Van's aircraft if they are installed
> with the over voltage protection sold by B&C Specialties. There have
> been several events where something happened that fried the internal
> regulator, but no one has been able to figure out the cause, so we
> have no fix yet.
>
> If you use an externally regulated alternator, you can use the over
> voltage protection sold by B&C Specialties (and designed by Bob
> Nuckolls). A small number of people have a philosophical problem
> with the way it shorts out the field line to cause the field CB to
> pop open, but no one has been able to demonstrate a real problem with
> the design. It is simple, and it works.
>
> So, my advice: if you want over voltage protection, go with an
> externally regulated alternator. If you judge the cost and hassle of
> replacing avionics to be less important than the cost and hassle of
> an installing an externally regulated alternator + over voltage
> protection, then go with an internally regulated alternator and skip
> the over voltage protection.
>
>
> Kevin Horton RV-8 (finishing kit)
> Ottawa, Canada
> http://www.kilohotel.com/rv8
>
>
> ________________________________ Message 4
> _____________________________________
>
>
> Time: 08:58:26 AM PST US
> Subject: RE: AeroElectric-List: Internal regulation
> From: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
>
> --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)"
> <frank.hinde@hp.com>
>
> Interesting thoughts Kevin...And a nice web site too!
>
> Of course I've already got my internally regulated alt and my avionics
> will cost a fortune..rather like yours in fact..:)
>
> I went with one of those kilovolt contators driven by an OV module and
> although I can't remember the numbers the break current was monstrously
> huge from my recollection.
>
> In short I have a hard time believing it will not break in a OV
> event...At least I hope it will..:)
>
> Frank
> RV-7A..airframe complete, need to paint cockpit.
>
> Dave,
>
> The first big question is whether you want to have over voltage
> protection or not. Some folks who have never heard of any over voltage
> cases on cars, figure that an automotive alternator with internal
> regulation is reliable enough that they don't worry about an over
> voltage. But, there was a message on this list a while back from a guy
> who had an automotive alternator on his aircraft that would go into an
> over voltage condition as soon as he selected it on. So, over voltages
> do happen.
>
> If your avionics are cheap, or you have enough money that you are
> prepared to risk them, you could go without over voltage protection.
>
>
> ________________________________ Message 5
> _____________________________________
>
>
> Time: 09:20:46 AM PST US
> Subject: AeroElectric-List: Re: AeroElectric-List Digest: 11 Msgs -
> 07/11/05
> From: "Glaeser, Dennis A" <dennis.glaeser@eds.com>
>
> --> AeroElectric-List message posted by: "Glaeser, Dennis A"
> <dennis.glaeser@eds.com>
>
>>Subject: Re: AeroElectric-List Digest: 11 Msgs - 07/11/05
>
>>From: Dave Harmon (vagabondpa15@verizon.net
>>Date: Tue Jul 12 - 7:07 AM
>>--> AeroElectric-List message posted by: "Dave Harmon"
> <vagabondpa15@verizon.net
>
>>Can we go over again why it's not rec. to use internal regulation on
> alternators.
>>Dave
> ------------------------------------------------------
>
> Bottom line: inability control the field current (elegantly
> enable/disable the Alternator output), and unknown OV protection.
>
> With most IR's, once the field is energized, it 'latches on' and there
> is no external way to turn it off - so there is no external way to
> disable the alternator in case of OV except by disconnecting the B lead
> (which also can cause problems - search the archives for 'load dump').
> Many modern automotive IR's have built-in OV protection, and may be just
> fine - but it is next to impossible to get technical info on them in
> order to make an educated decision. And even if you do, it would be for
> that specific (make, model) regulator, not IR's in general. Bob won't
> recommend something he can't verify (a reasonable position IMHO).
>
> Dennis Glaeser
> RV7A Empennage
>
>
> ________________________________ Message 6
> _____________________________________
>
>
> Time: 09:53:15 AM PST US
> From: Phil Birkelbach <phil@petrasoft.net>
> Subject: Re: AeroElectric-List: Internal regulation
>
> --> AeroElectric-List message posted by: Phil Birkelbach
> <phil@petrasoft.net>
>
> Excellent reply Kevin,
>
> I went with the internal regulated alternator with a contactor on the
> 'B' lead (B for Big right :-) ) and the B&C crowbar overvoltage device.
> I suspect that some day in the future the regulator inside the
> alternator will shed all of it's smoke at which time I'll have it
> overhauled and turned into an externally regulated type and buy a
> regulator. It'll be a simple change.
>
> The questions about the voltage spike killing the alternator, center
> around disconnecting the alternator 'B' lead while the alternator is
> producing current. My checklists are set up so that once I turn the
> alternator on it stays on until the engine isn't turning anymore. If I
> get the overvoltage event and the contactor opens it up then the
> assumption is that the regulator is fried anyway.
>
> Godspeed,
>
> Phil Birkelbach - Houston Texas
> RV-7 N727WB - Finishing Up
> http://www.myrv7.com
>
>
> Kevin Horton wrote:
>
>>--> AeroElectric-List message posted by: Kevin Horton
>><khorton01@rogers.com>
>>
>>On 12 Jul 2005, at 10:06, Dave Harmon wrote:
>>
>>
>>
>>>--> AeroElectric-List message posted by: "Dave Harmon"
>>><vagabondpa15@verizon.net>
>>>
>>>Can we go over again why it's not rec. to use internal regulation on
>>>alternators.
>>>Dave
>>>
>>>
>>
>>
>>Dave,
>>
>>The first big question is whether you want to have over voltage
>>protection or not. Some folks who have never heard of any over
>>voltage cases on cars, figure that an automotive alternator with
>>internal regulation is reliable enough that they don't worry about an
>>over voltage. But, there was a message on this list a while back
>>from a guy who had an automotive alternator on his aircraft that
>>would go into an over voltage condition as soon as he selected it
>>on. So, over voltages do happen.
>>
>>If your avionics are cheap, or you have enough money that you are
>>prepared to risk them, you could go without over voltage protection.
>>
>>If you want over voltage protection, and you use an externally
>>regulated alternator, the over voltage protection device can simply
>>cut the power between the voltage regulator and the alternator
>>field. This line only has small current in it, so there is no
>>problem to chop the power if an over voltage ever occurs.
>>
>>But, if you have an internally regulated alternator, the wire from
>>the voltage regulator to the field is buried inside the alternator -
>>you can't get at it. So, the only way to deal with an over voltage
>>is to have a contactor in the alternator output that is opened
>>automatically if the alternator runs away. This contactor will have
>>to open when the alternator is supplying as much current as it can
>>possibly do, and there is some question about whether the contactor
>>will actually reliably cut the alternator output, or whether it might
>>arc internally and weld closed.
>>
>>There have also been a few unexplained problems with internally
>>regulated alternators sold by Van's aircraft if they are installed
>>with the over voltage protection sold by B&C Specialties. There have
>>been several events where something happened that fried the internal
>>regulator, but no one has been able to figure out the cause, so we
>>have no fix yet.
>>
>>If you use an externally regulated alternator, you can use the over
>>voltage protection sold by B&C Specialties (and designed by Bob
>>Nuckolls). A small number of people have a philosophical problem
>>with the way it shorts out the field line to cause the field CB to
>>pop open, but no one has been able to demonstrate a real problem with
>>the design. It is simple, and it works.
>>
>>So, my advice: if you want over voltage protection, go with an
>>externally regulated alternator. If you judge the cost and hassle of
>>replacing avionics to be less important than the cost and hassle of
>>an installing an externally regulated alternator + over voltage
>>protection, then go with an internally regulated alternator and skip
>>the over voltage protection.
>>
>>
>>Kevin Horton RV-8 (finishing kit)
>>Ottawa, Canada
>>http://www.kilohotel.com/rv8
>>
>>
>>
>>
>
>
> ________________________________ Message 7
> _____________________________________
>
>
> Time: 05:57:51 PM PST US
> From: <bakerocb@cox.net>
> Subject: AeroElectric-List: split pin connectors
>
> --> AeroElectric-List message posted by: <bakerocb@cox.net>
>
> 7/12/2005
>
> OC, please pass on to Bob Nuckolls.
>
> A total of seven "split pin connectors" emanating from the autopilot, all
> blue in color were found behind the instrument panel of the Beech Sierra,
> Each one was first disconnected and then reconnected. No further trouble
> shooting took place before an operational test was conducted on the
> Century
> IIB autopilot. The test on the ground was successful, A subsequent
> airborne
> operational test also proved the autopilot to be fully operational.
>
> Thank you again for any time, effort and thought that went into this
> trouble
> shooting. George Philipps
>
>
> ________________________________ Message 8
> _____________________________________
>
>
> Time: 06:21:33 PM PST US
> From: <bakerocb@cox.net>
> Subject: AeroElectric-List: Re: ICOM PTT
>
> --> AeroElectric-List message posted by: <bakerocb@cox.net>
>
> AeroElectric-List message previously posted by: OC Baker
>
>> ....skip......But I don't know why they would mislead us about the non
>> functioning of the IC-A4 on set transmitter button while the headset
>> adapter is installed if the button and the radio works OK just like
>> Charlie Brame says it does for the IC-A23.
>>
>> ICOM Tech Support, do you wish to comment?
>>
>> OC
>
> 7/12/2005
>
> I went flying yesterday with a friend and conducted some ground tests with
> my ICOM IC-A4 hand held radio. Here is what I observed:
>
> 1) With the headset adapter plugged in and a headset connected to the
> adapter, the PTT button on the side of the radio activated the transmitter
> and normal transmissions could be made with the microphone built into the
> radio. Transmissions could be heard by the head set wearer (side tone) and
> a
> separate receiving radio.
>
> 2) With the headset adapter plugged in and a headset connected to the
> adapter with a standard large size PTT adapter cord (not 3.5mm) in line
> with
> the microphone plug the transmitter could be activated by pushing the PTT
> button on the adapter cord. Transmissions could be made with the headset
> microphone and could be heard by sidetone in the headset and at a
> receiving
> radio.
>
> Why the IC-A4 manual states or implies that the two operations above
> cannot
> be conducted is beyond me. Both of these modes of operation would be
> considered normal and advantageous by any one considering buying or owning
> a
> hand held radio.
>
> ICOM Tech Support, do you wish to comment?
>
> OC
>
>
>
Message 16
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| Subject: | Re: AeroElectric-List Digest: 8 Msgs - 07/12/05 |
--> AeroElectric-List message posted by: Charlie England <ceengland@bellsouth.net>
Dave Harmon wrote:
>--> AeroElectric-List message posted by: "Dave Harmon" <vagabondpa15@verizon.net>
>
>Thanks every body I now have a better understanding on internal voltage
>regulation. Do you think a dry contactor on the B+ terminal will act fast
>enough? What's your thoughts on a fusible link on the output (B+) lead and
>go directly to the battery. PS I don't have a lot of money in the radios but
>every nickel counts to me. I think that's what got me into this problem I
>bought a 90.00 denso 40 amp. min. Now I don't want to use it. Maybe I can
>takeout the reg. and go external.
>Dave
>
(digest snipped)
There are more opinions about this than the primer wars over on the RV
list & picking your favorite might not be easy, but here's mine.
It's much more likely to *cause* a problem than to protect yourself from
one by disassembling & modifying a Denso alternator.
My personal preference is to use an internally regulated alternator with
overvoltage detection to disconnect the B lead in the unlikely event of
overvoltage. The battery will absorb a *lot* of current & hold the
voltage to a reasonable level for the short time it takes the contactor
to open. I trust Denso's internal design & physical/electrical
integrity more than I trust running several extra wires & connections
around the engine compartment to make an external regulator talk to an
alternator. Just personal preference.
The fusible link isn't likely to prevent frying electronics; if the
battery is near full charge the voltage will likely rise high enough to
damage electronics before over-current would blow a high current fuse
link (assuming that there's no OV protection relay).
Charlie
Message 17
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| Subject: | Re: AeroElectric-List Digest: 8 Msgs - 07/12/05 |
--> AeroElectric-List message posted by: "Bruce Gray" <Bruce@glasair.org>
The fusible link is to protect the wiring from a high amperage event
(Short). OV protection is to protect the electronics from a high voltage
event. Apples and oranges.
Bruce
www.glasair.org
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Charlie
England
Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 8 Msgs -
07/12/05
--> AeroElectric-List message posted by: Charlie England
<ceengland@bellsouth.net>
Dave Harmon wrote:
>--> AeroElectric-List message posted by: "Dave Harmon"
<vagabondpa15@verizon.net>
>
>Thanks every body I now have a better understanding on internal voltage
>regulation. Do you think a dry contactor on the B+ terminal will act fast
>enough? What's your thoughts on a fusible link on the output (B+) lead and
>go directly to the battery. PS I don't have a lot of money in the radios
but
>every nickel counts to me. I think that's what got me into this problem I
>bought a 90.00 denso 40 amp. min. Now I don't want to use it. Maybe I can
>takeout the reg. and go external.
>Dave
>
(digest snipped)
There are more opinions about this than the primer wars over on the RV
list & picking your favorite might not be easy, but here's mine.
It's much more likely to *cause* a problem than to protect yourself from
one by disassembling & modifying a Denso alternator.
My personal preference is to use an internally regulated alternator with
overvoltage detection to disconnect the B lead in the unlikely event of
overvoltage. The battery will absorb a *lot* of current & hold the
voltage to a reasonable level for the short time it takes the contactor
to open. I trust Denso's internal design & physical/electrical
integrity more than I trust running several extra wires & connections
around the engine compartment to make an external regulator talk to an
alternator. Just personal preference.
The fusible link isn't likely to prevent frying electronics; if the
battery is near full charge the voltage will likely rise high enough to
damage electronics before over-current would blow a high current fuse
link (assuming that there's no OV protection relay).
Charlie
Message 18
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| Subject: | Power buss alt field breaker |
--> AeroElectric-List message posted by: plaurence@the-beach.net
Bob,
and others-
In figure Z-14 you show the typical 5A breaker architecture from the bus to term
6 (bus) of the LR-3
controller.
In Z13, you placed a fuselink between the bus and the 5A breaker.
Would you explain?
Thanks
Peter
Message 19
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|
| Subject: | CESSNA SPLIT MASTER SWITCH |
0.03 HTML_TEXT_AFTER_HTML BODY: HTML contains text after HTML close tag
0.06 HTML_TEXT_AFTER_BODY BODY: HTML contains text after BODY close tag
--> AeroElectric-List message posted by: "Travis Hamblen" <TravisHamblen@cox.net>
I have the CESSNA SPLIT MASTER SWITCH which came with nothing in the way of
wiring diagrams or schematics. Does anyone have a schematic or wiring
diagram for this thing?? I know it is stone simple, as I know where the
wires route to and basically how it works, but I don=92t know which wire goes
onto which terminal. If you want you can e-mail me directly.
Travis
TravisHamblen@cox.net
--
Message 20
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| Subject: | Re: EXPBUS OV Protection |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 01:19 PM 7/13/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Bret Smith" <smithhb@tds.net>
>
>Bob, you might get what you need here...
>http://support.anywheremap.com/idx/0/020/article/Avionics_Documentation_and_Reference_Materials.html
>
>Bret Smith
Checked it out but no joy. I need detailed schematics and bills
of materials to deduce OVP performance.
Bob . . .
Message 21
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| Subject: | Re: EXPBUS OV Protection |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 06:15 PM 7/13/2005 +0100, you wrote:
>--> AeroElectric-List message posted by: Gerry Holland
><gholland@gemini-resourcing.com>
>
>Bob Hi!
>
>Some information that may or may not allow you to make comment on EXP Bus OV
>Protection.
>
>http://support.anywheremap.com/pdfs/expbus_overvolt.pdf
>
>http://support.anywheremap.com/pdfs/exp2vsch.PDF
Found these from links folks have sent but they only
show block diagrams and speak of functionality. Without
detailed schematics and parts values, I can't see
how well they did the job.
Note further that EXPBus ov protection assumes an
alternator that can ALWAYS be controlled from the
"field supply" wire which does not include most
internally regulated alternators.
Bob . . .
Message 22
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| Subject: | Re: Alternator questions? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 02:00 PM 7/13/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Paul Weismann"
><pw@weismannassociates.com>
>
>Apologies if this topic has been covered but I searched and could not
>find...
>
>2 alternator questions:
>1. I am using a Denso automotive alternator in my turbine Rotorway
>helicopter. The generally used diagram for the alternator is to have
>TWO AWG12 b-leads running each to its own 30amp CB, and then TWO AWG12
>leads to a junction post linking the battery and starter. I was going
>to use the post on the starter for this.
> What is the benefit, if any, to using 2 wires - is it only
>redundancy, and if so, how much incremental protection would such a
>design offer?
None that I can deduce.
>2. In some of Bingelis' writings, he recommends having the alternator
>b-leads shielded. I do not see shielding in Bob's schematics (apologies
>if I am reading them incorrectly). Is it necessary?
No
Bob . . .
--------------------------------------------------------
< Throughout history, poverty is the normal condition >
< of man. Advances which permit this norm to be >
< exceeded -- here and there, now and then -- are the >
< work of an extremely small minority, frequently >
< despised, often condemned, and almost always opposed >
< by all right-thinking people. Whenever this tiny >
< minority is kept from creating, or (as sometimes >
< happens) is driven out of a society, the people >
< then slip back into abject poverty. >
< >
< This is known as "bad luck". >
< -Lazarus Long- >
<------------------------------------------------------>
http://www.aeroelectric.com
Message 23
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| Subject: | Re: PM Alternator / Regulator failure |
modes
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
modes
At 02:59 PM 7/13/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: Jon Goguen <jon.goguen@umassmed.edu>
>
>
>On Jul 13, 2005, at 1:57 PM, Roy Wheaton wrote:
>
> > The failures are most often an open or
> > shorted rectifier diode, or a shorted SCR. There are usually two SCR's
> > in
> > parallel, and it's rare for both to fail.
>
>Am I correct in thinking that none of these failure modes would result
>in an over voltage condition?
No . . . but ANY alternator that needs a REGULATOR can REGULATE
at the desired voltage or, depending on what part has failed,
can depart greatly from the design voltage.
Given that most PM alternators are relatively low current sources,
a GOOD svla battery (recombinant gas) will keep a runaway alternator
from driving the bus to the moon for several seconds. Perhaps 10-20
or more. One could CONSIDER an OV warning and a manual reaction to said
warning. However one chooses to go, manual or automatic, ANY alternator
of ANY size is capable of driving the bus voltage up to unhealthy
levels. It's just a matter of time.
However with the smaller alternators, this isn't a really fast
race. See last figure on the 8th page of
http://www.aeroelectric.com/articles/Crowbar_OV_Protection/DC_Power_System_Dynamics_C.pdf
where we see that a 30A runaway alternator may not raise bus
voltage high enough to trip an ov sensor set for 16.2 to 16.5
volts for quite awhile . . . perhaps minutes. Smaller alternators
take even longer. This presumes you've got a good battery that
will do its best to soak up all the excess electrons pumped out
by a runaway alternator.
For 40A machines an larger, I'd recommend fully automatic
ov protection.
Bob . . .
Message 24
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| Subject: | Re: Power buss alt field breaker |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 07:49 PM 7/13/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: plaurence@the-beach.net
>
>
>Bob,
>and others-
>
>In figure Z-14 you show the typical 5A breaker architecture from the bus
>to term 6 (bus) of the LR-3
>controller.
>In Z13, you placed a fuselink between the bus and the 5A breaker.
>Would you explain?
Z-14 depicts a breaker panel where the breaker feeding
field power to the LR-3 comes from bus adjacent to the
breaker.
Z-13 illustrates a fuse block were we're EXTENDING the
bus to a remote breaker for crowbar ov protection. That
piece of wire from the bus to the breaker would benefit
from some degree of SLOW protection, like a fusible link.
This is one of a FEW places where the fusible link is
a recommended wire protection device.
Bob . . .
Message 25
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| Subject: | Re: AeroElectric-List Digest: 8 Msgs - |
07/12/05
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
07/12/05
At 05:49 PM 7/13/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: Charlie England
><ceengland@bellsouth.net>
>
>Dave Harmon wrote:
>
> >--> AeroElectric-List message posted by: "Dave Harmon"
> <vagabondpa15@verizon.net>
> >
> >Thanks every body I now have a better understanding on internal voltage
> >regulation. Do you think a dry contactor on the B+ terminal will act fast
> >enough? What's your thoughts on a fusible link on the output (B+) lead and
> >go directly to the battery. PS I don't have a lot of money in the radios
> but
> >every nickel counts to me. I think that's what got me into this problem I
> >bought a 90.00 denso 40 amp. min. Now I don't want to use it. Maybe I can
> >takeout the reg. and go external.
> >Dave
> >
>(digest snipped)
>
>There are more opinions about this than the primer wars over on the RV
>list & picking your favorite might not be easy, but here's mine.
>
>It's much more likely to *cause* a problem than to protect yourself from
>one by disassembling & modifying a Denso alternator.
>
>My personal preference is to use an internally regulated alternator with
>overvoltage detection to disconnect the B lead in the unlikely event of
>overvoltage. The battery will absorb a *lot* of current & hold the
>voltage to a reasonable level for the short time it takes the contactor
>to open. I trust Denso's internal design & physical/electrical
>integrity more than I trust running several extra wires & connections
>around the engine compartment to make an external regulator talk to an
>alternator. Just personal preference.
>
>The fusible link isn't likely to prevent frying electronics; if the
>battery is near full charge the voltage will likely rise high enough to
>damage electronics before over-current would blow a high current fuse
>link (assuming that there's no OV protection relay).
Correct.
Fusible links, fuses, breakers, etc are for WIRE PROTECTION ONLY
and have no useful functionality for mitigating an over-voltage
condition. These circuit protective devices are recommended in
a variety of locations as shown in the Z-figures but none of
these devices is intended to be primary sensing/protection for
an ov condition. A crowbar OV protection module takes advantage
of a fuse or circuit breaker's willingness to protect the field
supply wire AFTER the crowbar module trips . . . but operation
of circuit protection is PAIRED with the ov protection module.
Neither device by itself offers any form of ov protection.
Bob . . .
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