Today's Message Index:
----------------------
1. 04:25 AM - Re: Re: New/rebuilt Alternators IGN wire (Was: real data on ovp/etc) (Kevin Horton)
2. 07:33 AM - Re: Toggle Switch & Breaker (Robert L. Nuckolls, III)
3. 08:46 AM - New/rebuilt Alternators IGN wire (Robert L. Nuckolls, III)
4. 12:33 PM - Re: Re: New/rebuilt Alternators IGN wire (Was: real data on ovp/etc) (George Braly)
5. 04:48 PM - Re: Re: New/rebuilt Alternators IGN wire (Robert L. Nuckolls, III)
6. 06:45 PM - Re: Re: New/rebuilt Alternators IGN wire (Was: real data on ovp/etc) (George Braly)
7. 07:04 PM - Re: Ferrels for use in screw connectors EDITED (DonVS)
8. 07:37 PM - Re: Re: New/rebuilt Alternators IGN wire (Robert L. Nuckolls, III)
9. 09:02 PM - Re:Real data on OVP/etc (disinterested?) Bob ()
10. 09:38 PM - Re: Re:Real data on OVP/etc (disinterested?) (Gerry Holland)
Message 1
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| Subject: | Re: New/rebuilt Alternators IGN wire (Was: real |
data on ovp/etc)
--> AeroElectric-List message posted by: Kevin Horton <khorton01@rogers.com>
On 6 Aug 2005, at 23:33, <gmcjetpilot@yahoo.com>
<gmcjetpilot@yahoo.com> wrote:
> --> AeroElectric-List message posted by: <gmcjetpilot@yahoo.com>
>
> Matt wrote:
>
>> Okay, you've fenced your paradigm in a bit tighter. You
>> seem to be suggesting that only a "brand new ND" alternator
>> is suited to operation in your proposed paradigm. Which
>> part number? Will it offer positive ON/OFF control via
>> the little wire out the back?
>
> Little black wire? I think on my wire harness it is yellow or
> green, but you are talking about the IGN wire that goes to the IR-
> internal (voltage) regulator.
>
> Positive ON/OFF Control? You don't need any POSITIVE control. When
> ever the engine is running the alternator should be ON, always.
> When ever you turn the master BAT switch OFF the alternator should
> be turned off (at the same time), while not under load (turning).
> You must never turn the BAT off with the ALT on. The IR is
> automatic and there is no need to manually control the alternator.
> If there is a fault it should shut down automatically.
>
> The IGN wire is not qusi ON/OFF switch. It is not the intent use.
> It does work as an ON switch in that if you start the engine with
> the ALT OFF (no power to the IGN wire) it should not make juice.
> However turning the alternator ON (power to the IGN wire) after
> starting the engine with it off, it will TURN ON. It will also FRY
> IT. Don't do it. May be you should read my SNIP.
>
> Now can you turn it off with the engine still running? I do not
> think so. My current plane and new 45amp ND are not running yet. I
> sold my last plane and can't go out and test it to tell you.
> However I would not even want to do it because there is no reason
> and I don't want to damage my alternator.
>
> Why do you want to manually shut the alternator off? Why? That is a
> bad idea. I never, never would turn the ALT or BAT off with the
> engine running (well except for one special condition). Why would
> you ever do this? What purpose would this serve? When would you
> shut a perfect alternator down with the engine running? The IR has
> it's own auto fault protections and will shut down. There is that
> rare OV case I mentioned in the previous post (SNIP) that in theory
> a scenario happens where nothing will turn the alternator OFF. As I
> said I never found any documented run-a-way cases with an IR Denso
> alternators. So what happens if this does occur?
>
How will you remove all electrical power from the aircraft in the
event you ever have a smoke in the cockpit event? In theory, the
fuses and CBs are supposed to prevent that sort of thing, but these
events still happen due to various wiring faults (e.g. an insulation
failure could cause a small ground wire to short to a large power
wire - the ground wire would smoke before the circuit protection on
the power wire would open).
The only way to remove all electrical power in most archetures is to
shut down the alternator and open the battery contactor. Even if you
aren't worried about an OV event, you should consider the smoke in
the cockpit case, as it could kill you, even if you are flying VFR.
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://www.kilohotel.com/rv8
Message 2
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| Subject: | Re: Toggle Switch & Breaker |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 03:37 PM 8/6/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "Bill Denton" <bdenton@bdenton.com>
>
>A couple of questions:
>
>What configuration of toggle switch (SPST, SPDT, etc) would I need to do the
>following:
>
> Down position - Off - Input not connected to any output
>
> Center position - Low - Input connected to one output
>
> Up position - High - Input connected to second output
This is accomplished with a two pole, three position, progressive
transfer switch like B&C's S700-2-10
Use of this swich is illustrated in a number of the Z-figures
in the book and in chapter 11 of the 'Connection.
>This would be used to feed a strobe power supply that offers both a low and
>a high output. A source of supply for this switch would also be appreciated.
>
>Second question:
>
>The Rotax 503 wiring diagram calls for a 15-amp fuse between the
>rectifier-regulator and the positive battery terminal. Would there be any
>reason not to use a combination toggle switch/circuit breaker, such as the
>W31X2M1G-15 from Wicks Aircraft Supply for this purpose?
How is the alternator tuned On/Off otherwise? If wired
per instructions, is there no way to turn it off?
One can always substitute breakers/fuses/switch-breakers
for each other.
Bob . . .
Message 3
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| Subject: | New/rebuilt Alternators IGN wire |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 08:33 PM 8/6/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: <gmcjetpilot@yahoo.com>
>
>
>Matt wrote:
>
>
> >Okay, you've fenced your paradigm in a bit tighter. You
> >seem to be suggesting that only a "brand new ND" alternator
> >is suited to operation in your proposed paradigm. Which
> >part number? Will it offer positive ON/OFF control via
> >the little wire out the back?
>
>
>Positive ON/OFF Control? You don't need any POSITIVE control. When ever
>the engine is running the alternator should be ON, always. When ever you
>turn the master BAT switch OFF the alternator should be turned off (at the
>same time), while not under load (turning). You must never turn the BAT
>off with the ALT on. The IR is automatic and there is no need to manually
>control the alternator. If there is a fault it should shut down automatically.
Very good sir. We've finally arrived at the mutual
level of understanding needed to resolve the new
paradigm.
Since day-one for the installation of power sources
in aircraft, the pilot has been offered positive control
of all sources in the form of panel mounted switches.
These were additions to other forms of positive control
like magneto switches (if you can start and stop the
engine by means of fuel controls, why do we need magneto
switches?), fuel shutoff valves, etc.
Many of these features became part of CAA and eventually
FAA requirements for certification. One might argue
that since much of what the FAA requires adds no value
to the safety of aircraft operation we can target
ANY and ALL requirements as superfluous or unnecessary
under any new paradigm we choose to embrace.
The simple-idea supporting your paradigm is that
you don't find it necessary to have positive control
over an alternator.
Now, if you wish to gain support of this paradigm, you
need to do a Case-A, Case-B comparison of the ideas
that support the Positive Control paradigm and demonstrate
how they (1) were unnecessary or in error, or (2) have become
obsolete with new technology or operating philosophies.
It is inadequate to state that this new paradigm's philosophy
is based only upon inarguable features of the latest-and-
greatest technology. You must also supply the logic needed
to encourage abandonment of the old paradigm. For example,
at one time, wax and whale oil were the illumination fluids
of choice and then kerosene came along only to be replaced by
evaporated "white gas" (naptha) blown through mantles, etc.
In each step, there were no compelling desirable features
being abandoned from the old paradigm and new paradigms
did not present unsurmountable or unacceptable features
(nobody was ever electrocuted by a Coleman lantern and
nobody ever set their house on fire by smoking while
screwing in a new lightbulb).
If you have such an case to make, I'm eager to hear
it.
Bob . . .
Message 4
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| Subject: | Re: New/rebuilt Alternators IGN wire (Was: real |
data on ovp/etc)
--> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com>
>Will it offer positive ON/OFF control via the little wire out the
back?<
>>Positive ON/OFF Control? You don't need any POSITIVE control. When
ever the engine is running the alternator should be ON, always. When
ever you turn the master BAT switch OFF the alternator should be turned
off (at the same time), while not under load (turning). You must never
turn the BAT off with the ALT on. The IR is automatic and there is no
need to manually control the alternator. If there is a fault it should
shut down automatically.<<
Oh... my goodness. Where to start?
I just finished doing a formal Functional Hazard Assessment for an
alternator system.
That, aside:
Something mundane. How about troubleshooting electrical problems in the
hangar?
Do you REALLY want the alternator field drawing 3 amps while you have
the battery ON ?
In the air, what if you get a "flying" short of the spinning alternator
windings that is intermittent while operating and causing lots of
voltage and current spikes/faults to drop into the electrical system - -
and you can't kill the alternator without killing the entire electrical
system and creating an emergency?
What if a diode fails and the level of electrical noise into the system
makes radio communication very difficult?
Regards, George
Message 5
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| Subject: | Re: New/rebuilt Alternators IGN wire |
(Was: real data on ovp/etc)
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
(Was: real data on ovp/etc)
At 02:30 PM 8/7/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com>
>
>
> >Will it offer positive ON/OFF control via the little wire out the
>back?<
>
>
> >>Positive ON/OFF Control? You don't need any POSITIVE control. When
>ever the engine is running the alternator should be ON, always. When
>ever you turn the master BAT switch OFF the alternator should be turned
>off (at the same time), while not under load (turning). You must never
>turn the BAT off with the ALT on. The IR is automatic and there is no
>need to manually control the alternator. If there is a fault it should
>shut down automatically.<<
>
>
>Oh... my goodness. Where to start?
>
>I just finished doing a formal Functional Hazard Assessment for an
>alternator system.
>
>That, aside:
>
>Something mundane. How about troubleshooting electrical problems in the
>hangar?
>
>Do you REALLY want the alternator field drawing 3 amps while you have
>the battery ON ?
This may not happen as long as you don't move the alternator
control switch to ON after closing the battery contactor.
>In the air, what if you get a "flying" short of the spinning alternator
>windings that is intermittent while operating and causing lots of
>voltage and current spikes/faults to drop into the electrical system - -
>and you can't kill the alternator without killing the entire electrical
>system and creating an emergency?
>
>What if a diode fails and the level of electrical noise into the system
>makes radio communication very difficult?
Good points for the positive control paradigm. Does anyone
have additional offerings for (or against) either paradigm?
Bob . . .
Message 6
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| Subject: | Re: New/rebuilt Alternators IGN wire (Was: real |
data on ovp/etc)
--> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com>
>Do you REALLY want the alternator field drawing 3 amps while you have
>the battery ON ?
This may not happen as long as you don't move the alternator
control switch to ON after closing the battery contactor.
*******************************
Bob,
I thought the "no control" paradigm assumed that when the BAT switch is
ON, that the alternator is powered - - with no way to interrupt the
alternator. Right?
In that case, the bus voltage will be <12.5 and the alternator field
should be 100% energized, since the VR sense voltage set point will
normally be > 13.8 Volts.
Am I missing something ?
Regards, George
Message 7
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| Subject: | Ferrels for use in screw connectors EDITED |
--> AeroElectric-List message posted by: "DonVS" <dsvs@comcast.net>
Bob,
I goofed on the spelling of ferrules. Please see
www.alliedelec.com/catalog/pf.asp?FN=101.pdf. The AFS2500 uses a screw
connector where the screw moves a jaw like device together. The contact
area is about half that of a faston blade. I think that the ferrules and
this type of closure device should be adequate, but would like your thoughts
on this. Thanks. Don
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert
L. Nuckolls, III
Subject: Re: AeroElectric-List: Ferrels for use in screw connectors
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<nuckollsr@cox.net>
At 11:27 AM 8/5/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: "DonVS" <dsvs@comcast.net>
>
>Bob or anyone who knows,
>I have a new AFS 2500 engine monitor and it has screw type connectors. I
>like the unit and want to use it. Does using a ferrel on each wire make
>this device less likely to have problem connections? TIA. Don VS
Depends on what the "ferrel" does. If it adds insulation
support, it might be a useful thing to do. I doubt that quality
of the connection goes up where the screw mashes down on
something hoping to maintain electrical integrity. I had
one reader suggest that you crimp the smaller diameter molex
pins (.062") onto each wire and then put the pin into the
screw-clamp. This would certainly help provide mechanical
support for vibration resistance . . . but probably won't
help with electrical integrity.
Bob . . .
Message 8
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| Subject: | Re: New/rebuilt Alternators IGN wire |
(Was: real data on ovp/etc)
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
(Was: real data on ovp/etc)
At 08:43 PM 8/7/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com>
>
> >Do you REALLY want the alternator field drawing 3 amps while you have
> >the battery ON ?
>
> This may not happen as long as you don't move the alternator
> control switch to ON after closing the battery contactor.
>
>
>*******************************
>
>Bob,
>
>I thought the "no control" paradigm assumed that when the BAT switch is
>ON, that the alternator is powered - - with no way to interrupt the
>alternator. Right?
>
>In that case, the bus voltage will be <12.5 and the alternator field
>should be 100% energized, since the VR sense voltage set point will
>normally be > 13.8 Volts.
>Am I missing something ?
Oh, I guess I don't know how Van suggests that it be wired, nor
do I know how George was suggesting it be wired either. I HAVE
seen a number of articles and drawings where the IGN wire was
routed through a conventional alternator control branch of a
split rocker . . . which would be emulated nicely by use of the
2-10 progressive transfer. This would allow the pilot to get the
engine running before adding alternator loads. However, if
wired as I suggested in earlier drawings where a 2-3 was
used for DC PWR MASTER, then of course, the IGN terminal would
"get hot" with the bus.
Then, there's yet another configuration of modern alternators
that offer the so-called, "one-wire" solution. These guys
are popular with the marine and hot-rod crowd. Of course the
b-lead is always hot in these vehicles.
Having said that, some of the chips have an AC sense lead
that gets a signal from the stator leads. Depending on the
chip designer's philosophy, this signal could be used to disable
the field when the alternator was not turning.
An example of this philosophy can be viewed at:
http://www.irf.com/product-info/datasheets/data/irvr101.pdf
This puppy even offers a 9600 baud serial port for
data transfer between chip and a monitor/control
system.
No doubt about it folks . . . there's a whole lot of
whippy things goin' on out there. There may be a great
temptation to embrace these new things. But we should
take care lest we find ourselves in a new, unanticipated
mode of operation by way of an unhappy surprise.
Bob . . .
>Regards, George
>
>
>--
>
>
>-- 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 9
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| Subject: | Re:Real data on OVP/etc (disinterested?) Bob |
--> AeroElectric-List message posted by: <gmcjetpilot@yahoo.com>
From: "Robert L. Nuckolls, III" nuckollsr@cox.net
Subject: Re:Real data on OVP/etc (disinterested?)
> It depends on your paradigm . . .
That was my whole point. Bob you are focused on one small aspect. Aviation safety
is a much broader subject than voltage regulators.
>Which is not an opinion sir. Nor is it a preference for anyone's
>stew. For the past 70+ years, folks flying airplanes have had
>switches on the panel that offer (1) absolute control over all sources
>of power in the aircraft and (2) has a remote probability of a failure
>that propagates across multiple systems. The FAA requires that I
>work within that paradigm when offering up new systems for certification.
You missed the point. Opinion does guide your perspective. I dont worry what the
FAA says. You are also uninformed about alternator control; I do have complete
control of my IR regulator. If all hell breaks loose, I can pull that big-old
B-lead 50 amp panel mounted CB out. (In a real emergency the BAT master off
. My engine and flight instruments are not electrically dependent or are automatically
backed up with internal batteries, Dynon, Garmin.) The only way to
get true fail-safe or fail-passive system is at least two or three fully ISOLATION
and independent electrical sources working side by side.
>I'm completely mystified by this statement. How does the fact that
>the FAA will or will not bless any particular reasoning make it
>an automatic no-brainer for someone building his own airplane?
>This isn't about regulations or opinions, it's about design goals
>that satisfy the paradigm under which the owner/operator of the
>end product. 99+ percent of OBAM airplane builders are comfortable
>with and most understand the paradigm that controls how certified
>airplanes operate.
Bob dont be mystified. That is so condescending. What I wrote was so bewildering,
you became disorient and confused. Wow I did not know my words had the power
to mystify. No one is proposing a panacea here Bob and were ae a lot smarter
than you give us credit for.
>Do you have data about how the various IR alternators operate such
>that you can DEMONSTRATE that anything with ND's name on it will
>operate in the paradigm that applies to the vast majority of airplanes
>flying? If not, then your recommendation is not backed up by
>demonstrable and consistent performance characteristics and is,
>in fact, purely a preference for a different taste in your
>bowl of stew.
Do I have data? Bob, that is an inane thing to ask. There are 148 models of ND
alternators with internal regulators and internal fans ranging from 30 to 130
amps. There are 66 models of ND alternators with external regulators and internal
fans from 90 to 136 amps. Plus there are another 15 various models with
external fan models. There are a few million ND alternators in daily use, 24 hours
a day, every day of the year working with excellent performance and reliability.
If this does not prove, demonstrable and consistent performance characteristics,
to BAD. All your posturing is absurd. You seem to lack common sense
and reasonable rational. These are experimental planes. If you have never been
in one, there is a warning placard that informs passengers that an experimental
airplane does not meet standard aircraft certification standards. Bob, I never
said my recommendation was a substitute, replacement or better than your
brilliant concepts, architecture and philosophies.
>No argument there. None-the-less, folks continue to
>come forward with their failure experiences. Not a "current
>generation ND alternator? Don't know. Not a stock
>regulator? Don't know. Would a well considered ov
>protection system of ANY flavor have saved the day?
>Probably . . . likelihood of dual failures in same
>system on same flight are extremely rare. At least
>one customer with the b-lead contactor and OVM-14
>crowbar module has written to me expressing relief
>that the system was in place when his IR alternator
>went tits up.
Bob, I am glad people write you to relive themselves. I think part of that relief
is from all the misinformation and rumors about IR alternators you spread.
With all the sensationalized talk it is easy to see how someone could have an
unreasonable heightened sense of concern. What folks continue to come forward?
You are the master of inflammatory insinuation. How many accidents have been
caused by an OV and did they involve a ND alternator? ZERO. You have a better
chance of your 0-2 gage-battery cable grounding, burning thru the engine mount
or just falling off. Electrical system failure is a very small % of the total
GA accidents. Statistically, regardless of where you put the regulator or if
you use a crow bar or not, your accident statistics will not change.
>But do you agree that the risk is not zero? In fact,
>one of our brothers here on the list reported such an
>incident recently. If I were trying to convince someone
>of anything, I could have wished that Jack's failure would
>have occurred two hours out, at night, over mountains
>and took out a bunch of radios to boot. When one is looking
>for propaganda fodder, the sweat-drenched, nail-biting
>stories are much more useful. Gee Jack, you let us down.
Bob that is just more emotional sensationalized comment is not worthy of an engineer,
that you claim you are. You are clueless, I mean ignorant to the meaning
of incident. This is what a pilot would do Bob: Over the mountains you loose
your alternator; Turn off all your non-essential electrical stuff and continue
to fly. You pull the ALT circuit breaker and the B-lead breaker. When you get
near your alternate (nearest suitable airport) you turn the electrical stuff
back on and land. Modern avionics like GPS pull a few 1/10th of an amp, so you
could run on BAT power for a while. Nighttime you should have a flashlight.
If you have a glass cockpit you should have enough battery power for at least
30-45min VFR and an hour plus for IFR. If you also have electronic ignition and
fuel injection, all electronic you would need a bigger back-up battery. Dual
alternators?
My viewpoint is use a Lycoming with a mechanical fuel pump, at least one magneto
or P-mag. A carburetor or mechanical FI does not need electrical power either.
The Dynon, GRT-EIS-4000, Garmin and other misc items are pulling about 5
amps total. The Dynon and GPS have self-contained batteries as well. My engine
is electrically independent as I feel it should be. I understand fault tolerance
Sir.
>Please consume it in good health.
Thank you. Pass the crackers
>You absolutely missed the point. Again, this has nothing
>to do with how much this system would please or displease
>me, the FAA or anyone else. It has everything to do with
>operating within the paradigm (which the FAA happens to
>like - as do the vast majority of OBAM aircraft builders).
Bob, no you missed the point again. /Operating within the paradigm/ is gibberish
that has no practical meaning to anyone. Common sense is the paradigm Bob. If
you cant dazzle-em with facts, baffle-em with the word paradigm.
It is not an affront to you or any device you have worked on. I have studied your
every word and understand it. I just dont want a device that SHORTS to ground
to work, no matter how clever or certified it is. I dont really care what the
FAA thinks as long as I get my paper work signed. It is my butt and for a VFR
plane, with no main buss electrical dependency to stay in the air, I am safe.
What else can I say? What dont you understand? I designed my system to eliminate
the need for a crow bar and external regulator. From personal experience
with a ND alternator in my cars and plane, I expect over 4000 hours of operation
before failure (200,000miles & 12 car years). So when my alternator reaches
2000 hours or 8 years I will remove and replace it.
>You remind me of individuals who have a lot of opinions
>about a book they've never read. The crowbar OV
>protection system IS certified sir, several times over. I've
>stated this numerous times in this thread. All of B&C'S many
>STC'd installations of both belt and pad driven alternators
>use the LR/SB series regulators all of which have crowbar
>ov protection.
I must remind you of yourself, since you talk about stuff you are clue less all
the time. When the guy with the Subaru had the electrical failure you pontificated
and criticize with little knowledge of facts. When you stated how B&C starters
are better than Sky Tec with bushings and blaa blaa, The Sky Tec guy put
you in your place. You should have apologized but you replied with something
stupid comment about lets do some test. Again you did not have the facts. I am
not perfect but you are ignorant.
You also remind me of someone who loves to argue. I see B&C has a standby alternator
system for the Bonanza and C210. Good for B&C. So I was not up to date.
Sue me. Apologies. Do they have any STCs to replace the main alternator on any
plane? If no, than why?
>You couldn't offend me if you tried. I won't permit it.
>You do amaze me with your lack of understanding
>as to what the real issues . . .
There you go again. What does that mean, I WILL NOT ALLOW IT. Whatever Bob. I was
making a sincere jester of concern and you throw it back at me as if I was
inconsequential and beneath you. I understand I am not worthy and of no importance.
>This isn't about ov protection. It's about control.
>Does your ND alternator of choice turn ON and OFF
>at the flip of a switch? Once it's in operation,
>can it be turned OFF? Do all alternators with the
>ND brand on them operate in this manner? How does
>one insure at the parts counter that the alternator
>being considered will operate within the currently
>accepted paradigm?
Engineers? Bob you cant control everything, you only think you can. I cant think
of a reason why I would turn off a perfectly good alternator with the engine
running. If it did crap out I would pull the B-lead CB in my panel. That would
essentially isolate it from the electrical system. (Yes I want control of my
B-lead and opt NOT to use a FUSE under the cowl where I cant access it, as you
suggest.) If I did not have the CB for the B-lead I could shut the BATT master
off. The engine would continue to run. The Dynon and GPS would be powered by
internal batteries.
>If not, then you're proposing a new paradigm. Which is
>fine . . . but be prepared to explain it in sufficient
>detail that everyone knows the physics upon which your
>recommendations are based . . . and they understand and
>accept the new paradigm. This has nothing to do with
>opinions, only facts and customer perceptions of value
>in the proposed paradigm.
I dont have customers. I am an individual and have stated so. As I clearly stated
your paradigm (oh I hate that word) is valid and needed based on your position
as guru. I dont have to prove anything. I have been honest in saying that
ND alternators have gained over a thousand of hours on single airframes. Personally
800 hours of ND time in a plane and a total of approx 6000 hours in three
automobiles (with ND alternators). As for the auto applications, the highway
safety foundation has never had a problem with ND alternators, which is not
true of many other alternators. Since records are not kept for experimental fleet,
I am going by my experience and those of other RVs (some with 2000 hours)
over 15 years. Not real scientific but it works.
>That's a no-brainer sir. 99% of all failures in all
>systems are passive. That's what keeps FBOs in business
>fixing all those things that broke and didn't bring the
>airplane down (or put the pilot into a situation he
>couldn't handle). The vast majority of accidents do not
>involve systems failures of any kind.
Cant argue with you because you are a Master Debater.
>A romantic philosophy sir, but even the greatest of
>chance-takers took great pains to understand the territory
>into which they planned to venture.
Chance-Taker? Bob you have such a PIN HOLE view of the world , aviation and aviation
safety, or at least you sound like it. I am bewildered and confounded by
your very ignorant words. I am dizzy with disbelief. You dont know me and I am
a very conservative ATP. This is just another feeble insult and a smoke screen
for the lack of an intelligent comment with substance. I dont know what is
romantic Sir, but I read what builders want to do. It is clear they are trying
to make it perfect of totally fail-safe. Which is impossible with any of your
suggestions or paradigm. If you like I will explain how an air transport category
planes electrical system works to illustrate how unsophisticated our little
DC electrical systems are.
>This would be amusing if it weren't so serious. In one breath
>you extol the virtues of a "brand new" ND alternator while
>in the next, you cite the value of de-rating to 30 amps,
>supplying cooling air, modifying operating techniques that
>don't bother the alternator on a C-172 but might be stressful
>on the brand new ND . . .
Well Bob, for someone who claims to know how an alternator works, you appear to
have a lack of any comprehension. I am not extolling any more than you are singing
about the 7 th wonder of the world called a Crow bar. WHAT DO YOU MEAN?
Look here, fact, semi-conductors life and reliability is a function of temperature.
YOUR B&Cs alternator has a diode pack (semi-conductors) on board just like
the ND, regardless of VR location. I guess B&C uses the exact same stock diodes
all ND alternators have. Keeping them cool is key to any alternator life.
I am using COMMON SENSE here, which you seem to be lacking from your fixation
of the crow bar or center of the galaxy. If you want to assure super reliability
de-rate your continuous % load. What % 50, 75? It is only a guide line Bob,
don't be a pisser. Some cars have shrouds and duct air to the back of the
alternator. Why? Cooling. Real engineers understand this and would not make such
an inane comment. Size your alternator accordingl
y. ND
makes 80 or 90 amp alternators I think are the physical size as the 60 amp. Just
common sense not quantum physics. If you can fit it there are 117-136 amp ND
alternators designed for an external voltage regulator out the Box!
>You cite facts not in evidence. The LR series regulators
>were tuned to provide the slightly under-damped servo response
>for step functions in both command and load. It's a classic
>taks for tailoring servo response. If the internal regulator were
>so whippy, LOAD DUMP ISSUES WOULD NOT EXIST. It's a regulator's
>inability to control the worst case load reduction that
>causes the high energy voltage transient.
You cite facts not in evidence? Bob, what the heck do you mean? Whimpy? What kind
of engineering term is that? That is how they work by design.
AGAIN FOR THE 10th TIME CUTTING THE B-LEAD OF AN IR ALTERNATOR IS NOT GOOD FOR
THE ALTERNATOR. IF YOU WANT A CROW BAR USE AN ALTERNATOR WITH AN EXTERNAL REGULATOR,
OR TAKE YOUR CHANCES WITH FAULTS CROW BAR TRIPS. GO AHEAD, USE A IR ALTERNATOR,
IT IS OK WITH ME.
EVERY ONE KNOWS RUNNING AN ALTERNATOR NOT CONNECTED TO A BATTERY IS BAD BAD BAD.
WHY IS THIS HARD TO GRASP BOB?
You claim to understand failure analysis. I doubt it. If you were driving your
car and the b-lead shorts (before the fuse), would you want the alternator to
burn-out (fuse) or keep working and act like a welder and set the car on fire?
(I have no idea what you will say, really, you would argue with a rock.).
We know the OV trip caused the demise because after this event the alternator did
not work anymore. ND engineers no doubt assumed this would be a rare event
(because they dont recommend OV cutouts by default. There are no OV relays in
non-aircraft applications). The IR has many functions and one of them looks at
the B-lead. While under load it will assume a short or other fault, which it
does monitor (because ND said so). Also the IC chip is connected to the B-lead
and it just might be too much for it. SO WHAT. This is condition is avoidable.
ND accepted this failure mode because it is not suppose to happen and is safer
than making a welder out of it.
>Come on over to B&C . . . I'll show you one.
OK, Ill take a rain check I would love to see that
>What's this mean? It's got 10-100x the transistors and they're
>all on a chip instead of soldered to a board. There are features
>that the older designs don't have but none of these things
>point to any "better" performance with issues you've cited.
Bob I think you have IC envy. Yes Bob more transistor means more features and performance.
You heard of computers? Well they have millions of transistors on
a small chip. More transistors the faster it works. If you built a computer like
you build your B&C VR, it would be the size of a house. I would think you could
grasp that. The IC chips inside most modern alternators does have logic circuits
(digital processes) and self-fault monitoring. DENSO will not send me
the schematics to their proprietary IC design. What I do know about special IC
chips is they are made by a handful of manufactures. They all seem to have similar
features. Here is a typical IC spec data sheet:
http://www.freescale.com/files/analog/doc/data_sheet/MC33099.pdf
>It's Eric's product as I recall, not Paul's. Further, it has
>nothing to do with nuisance tripping. It illustrates a means
>by which an IR alternator can be CONTROLLED irrespective
>of the reason for controlling it. OV protection is but one
>more layer on a system that's already several layers deep.
My mistake, yes it is another layer. I have read spec sheets on devices. If you
must use a crow bar on an IR regulator it might be a good add on (another add
on). It might help the OV relay from arcing as I think you and Paul have argued
about.
>You're entitled to accept any paradigm you wish. Just be
>sure your audience understands the paradigm shift when
>the proposed system does not operate like the one in
>a C-172.
Thank you for telling me I am entitled to an opinion. I dont need your permission
to have an opinion but thanks. Let me make it simple for you, the engine should
never stop turning in flight. Most GA planes have engines with no reliance
on external electrical power, or should. That is a good thing and should be
emulated at all cost. I understand Auto engines need power for the ignition/fuel
injection and pumps. That is one reason why I would not use an auto engine.
However an IR alternator could still be used, but you should have an isolated
power source. You never considered a DC-DC converter (battery charger) to charge
isolated battery. This is used on transport category planes.
>This is not rhetoric to state that if the transistor shorts,
>the alternator takes off for the moon. It is not rhetoric to
>state that some IR alternators cannot be externally controlled
>for normal operations, much less for recovery after a failure.
>for normal operations, much less for recovery after a failure.
>These are called deductions based on failure mode effects analysis.
Like you asked me several times above, do you have data? Look up the word rhetoric.
You should know what it means since you used it: rhetoric: The art or study
of using language effectively and persuasively.
By throwing in the word Deduction and Failure Mode Effects Analysis in one sentence,
I know you are shooting smoke. WHAT ANALYSIS DID YOU DO? FMEA is a term
that describes the tools people use doing risk based assessments and root-cause-analysis.
It is used in all kind of industries and processes. I see no analysis
but just a lot of words Bob. Now I did not say I did formal FMEA, but I did
go thru all the scenarios and made a DEDUCTION. I am not impressed when you
throw a few words around. Where is this analysis? If you dont have it you are
just spouting RHETORIC. My Risk-matrix result, for an IR alternator, in a little
single engine plane, no engine or flight critical system dependence on electrical
power, concludes the RISK is acceptable. With a B-lead CB in the pane
I can control the alternator.
>Numerous folks have experienced failures of IR alternators. Some
>of them were ND alternators. Since we might expect to be in
>communication with perhaps 5% of the OBAM community, it's not
>a stretch to suggest that 3 hard failures I'm aware of over
>the past 8 years has been repeated 20X for the community at
>large.
Numerous? OK Bob what ever you say, Failures. Hard failures? You dont even know
what the word incident means. Like you asked me several times above, DO you have
data? Prove it to me. You are throwing out numbers: 20 times, 3 to the power
of perhaps? You are real loose with the numbers. What does that mean? What
hard failure? What happened? I mean really Bob, you are hypocritical when you
ask for data and expect to give none in return Sir. Other wise it is hearsay,
innuendo and rumor. A few of these I tracked down where totally irrelevant
and where factory planes with external regulators. Forget the Failure analysis
Bull, how about some simple details. Basically WHAT HAPPENED? My I suggest if
you had a smoking gun to support your view you would say so.
>Jack's experience was not mitigated by the fact that
>his alternator was "not in a wild run-away" . . . the
>battery was the only thing standing between his
>failed alternator and all the other electro-whizzies
>in his airplane. If the battery had been used up
>or even disconnected, the voltage would rise much
>faster and much higher.
Oh, Bob you dont know that. It was mitigated by the fact the voltage regulator
was still functioning; it was no big deal. Voltage was between 13-16 volts. I
am sure in a few years this case will grow into a fairy-tale where the pilot was
electrocuted and the plane bust into flames from exploding avionics. It is
all sensation but no facts. Take a deep breath. No harm no foul. Yes the battery
helps any alternator. That is why my you dont disconnect it from the battery
normally. If you do the alternator might be damaged.
>Okay, you've fenced your paradigm in a bit tighter. You
>seem to be suggesting that only a "brand new ND" alternator
>is suited to operation in your proposed paradigm. Which
>part number? Will it offer positive ON/OFF control via
>the little wire out the back?
I address this in my post: Re: New/rebuilt Alternators IGN wire (Was: real data
on ovp/etc)
>This isn't about reliability. It's about failure mode
>effects. If the B&C goes south, it shuts down passively
>and lights the light. Then we bring "plan B" on line
>and continue the flight in comfort. This may not conform
>to your idea of component reliability, but it does
>conform to my idea of SYSTEM reliability.
If it never breaks you dont have to worry about failure mode. Plan B applies just
as much to a ND alternator as it does to anything you suggest.
>If you're looking for component reliability, you're
>correct. If you're looking for system reliability,
>my data is backed up by FMEA supported by 15 years
>of field history and a lot of experience in conducting
>such studies.
There you go. You have 15 years of crow bar data in experimental aircraft? Wow.
Well the basic ND design has been around for well over 15 years. I believe you,
but how did you get the data. You claim you conducted 15 years of field history
study. How many are in service? What about the failures happening, which
you have no idea of? One weak link in the home built world is there is no requirement
to collect maintenance data. You will see maintenance bulletins the FAAs
prints pertaining to all planes and sometimes a Kit plane will be in it, but
most non A&P builders of experimental aircraft dont report or read this publication.
There should be a FAR that requires or makes it easy for builders/repairman
to report maintenance issues, including electrical. That way we would
know whose alternator is failing.
>So let's "assume" that it isn't?
Now Bob dont be that way, you have muddled the point. You have a vested input to
the B&C design. You are proud and should be. I can see plainly that discreet
components and a crow bar is going to have a known failure mode. It does not
mean it will not fail more, but you understand how it fails. I can say my ND alternator
will be very reliable, but if it does fail, it might fail in unknown
modes. I know it is reliable and will not kill me, from my FMEA analysis I did
on a cocktail napkin.
>Until a couple of years ago, I was tightly coupled to
>B&C's field experience with their products. I worked out of
>their booth at OSH 12 straight years. I've talked to
>thousands of B&C customers (both happy ones and unhappy ones)
>Our warranty was "no unhappy customers" . . . EVERY customer
>was encouraged to bring any problem back to B&C for resolution.
>You're assertion with respect to pointing at B&C's problems
>is wishful thinking on your part sir. I've been there
>and it was my job to design products with a high degree
>of SYSTEM reliability and to quickly resolve what few
>problems did arise.
I think you are super defensive and sensitive, Sir. I wish to point at nothing.
I dont even know about all the past problems. I am not trying to discredit anything
or anyone. I think B&C is over priced not defective. However I think many
comments regarding the danger of using an IR alternator ignores the high degree
of reliability. The ND is an unknown since we cant look into the IC chip.
However that is moot since you EXPERTS have isolate the weak link, the field
driver transistor, not the IC chip. As I said the ND engineers are NOT ignorant
and these products are very mature. Regardless, you can always pull the B-lead
CB manually (if you have one and you should.
If you want to protect an individual piece of avionics, you can use a device like
a TransZorb(tm) or Mosorb that will break down at a set voltage like a zener
diode. This will blow the fuse or CB for that item (like a crow bar). This may
not be necessary since most modern electronics which have internal OV protection
and can take 30 volts and 60 volts spike (except icom a-200). Also no one
can put an exact max voltage on an OV condition. The last one was 16 volts.
Yawn, no worries.
> I have talked to Van many times. I've asked to do a weekend seminar
>for their staff like I did for Lancair. I'm going to do
>one in their neighborhood and HOPE some of their staff will
>attend. I may have to specifically invite them and/or offer
>free tuition.
That is real nice of you. Why call the man ignorant? Did he NOT get all excited
about FUSES, central ground and crow bars? Really there is nothing really new
under the sun Bob. Van has common sense and an eye on the BIG PICTURE, not just
the minutia of one possible electrical problem that is not that common any
more. (In the old days there where lots of OV because the external VRs where crap.)
>I'll suggest that you know nothing about design details
>and philosophy of anyone's built in regulators . . . nor
>are you privy to schematics upon which one bases a failure
>mode effects analysis.
Oh Geeee Bob, I suggest you have not processed the info. I told you at least 4
times I cannot get any detailed info on the IR chip inside a ND. I got some general
sales claims about OV and Load Dump protection but nothing real technical.
Again Load dump means 5-10 amps, not 30-60amps during a B-lead abortion from
a crow bar. I have studied spec sheet for other brands of IC chip sets use
for alternators. Also I have talked to NDs tech support in the US and looked maintenance
manual schematics (void of details inside the IC). They dont EVER recommend
cutting the alternator loose from the battery. Other than that both my
cars and my plane have ND alternators with internal regulators.
>They BLAME the ov system for killing an alternator when
>if fact, root cause for the failure comes from attempts
>to CONTROL the alternator. The alternator with a b-lead
>contactor is vulnerable to the same kind of failure whether
>or not OV protection is a part of the control system.
>Again, call it what you will . . .
I dont think it is a big deal Bob, dont be so sensitive. The crow bar got a little
reputation for toasting ND alternators. No one is blaming your little baby,
but there seems to be a cause and affect (Root Cause Failure Analysis per basics
of FMEA you claim to understand). It seems there is a correlation. Look IR
alternators are designed and installed in their auto application with out a
crow bar. If you must use an IR alternator make sure the crow bar is of best design
and adjusted so a false trip is unlikely. If it does POP and kill something
than that is the cost of doing business with extra protection. I will not
tell you about one dark and stormy night over the mountains when the crow bar
blew, since that is moot and dumb emotionalism.
>I've talked to Van at OSH and at several fly-ins.
>You betcha. When it comes to airframes, engines and flight
>controls, I am ignorant. I also don't know squat about brain
>surgery or particle physics. Van's forte' is demonstrably NOT
>founded in the physics and practice of fabricating electrical
>systems. His "kit" drawing is 1950's C-172 in which he has
>substituted a modern, IR alternator. "Ignorance" is not a
>pejorative but an accurate description of demonstrable
>fact.
OK Bob how much as electrons changed since 1950? My guess 1950 and 2005 electrons
are the same. I cant believe there is anything real bad about a 1950 Cessna
with the added IR alternator. We are talking about DC circuits. Bob here is your
distinguish wiring (MO) Modus Operandi:
-Central Ground (excellent idea I might add)
-B-lead fuse forward of firewall , connect to battery before buss**
-Automotive fuse block and ATQ blade fuses
-Spade connectors vs. ring
-Crow bar
**( Use of B-lead fuse vs. a panel CB sacrifices alternator control. Suggest the
overstressed claim of noise be ignored and use a panel CB, especially if you
use an IR alternator. I find it ironic Bobs technology is right out of an import
car. Japanese car imports pioneered this approach to DC power distribution.
The plastic fuse blocks are right out of a car. Bob likes, auto technology and
wiring, but does not like the IR alternator for lack of control. Well if you
use a CB for the B-lead in the panel, you have control.)
Circa 1950s Cessna (and Beech / Raytheon ) probably has crazy wily-nily grounding
schemes using multi point airframe grounds too much. It also probably has a
big fat CB on the panel for the B-lead, which is no big deal. As far as materials
I dont think Van uses 1950 wires and connectors. I am sure his kit uses
new mil spec wires and modern crimped connection. HOW BAD COULD IT BE? I looked
at Tony Bingelis Books and than yours, Bob. Wires are wires. DC circuits are
DC circuits. We are talking about a simple DC power distribution system. You
dont know Van. It is not ignorance; he just does not give a rats ass about the
smallest of electrical details that will affect .0001% of his builders. If it
gets the job done, than it is good enough.
>Which part number?
It is not my job to recommend alternators bob, but hear are some I hear has worked
for RV builders: The usual suspect are Nippondenso 100211-400; (1988-85) Chevrolet
Sprint 1.0L Nippondenso 100211-415; (1988-87) Chevrolet Sprint 1.0L
(1995-86) Suzuki Samurai 1.3L (1989) Suzuki Sidekick 1.3L Nippondenso 100211-141,
100211-155, 100211-407; (1991-85) Toyota 4Runner, Pickup 2.4L (1985) Toyota
Celica 2.4L Nippondenso 100211-203, -316, -355
>Except that we CAN design an electrical system that will
>NEVER be a link in the chain of events contributing to
>a catastrophe
Can never say NEVER in an airplane Bob. That is the answer I expect from an electrical
engineer. You can try and believe you have designed the perfect system,
but there is nothing perfect. A little piece of foam destroyed the space shuttle.
Apollo 13 went boom from a faulty heater.
>Voltage regulators are not the issue. Alternators you
>cannot control are the issue.
Oh Bob Bob Bob, you love to sensationalize, you CAN control an IR alternator: First)
Pull the B-lead CB or Second) Turn the master switch OFF. You have isolated
the alternator. I understand what you are saying, but statistically you are
myopic. The pilot is the key to safety not the engineer. Even a crap electrical
system is the most reliable thing on a small plane. Loss of an alternator
should not be fatal. What is a pilot doing flying IMC of mountains at night. You
are a typical design engineer that feels you can control everything. I understand
your engineer mentality. I dont care about a crow bar; I care about living.
Dont over estimate the significance of this one item to miss the big picture.
By adding this protection device you introduced another failure point. Does
it justify adding it?
>George, the boat sailed and you weren't on it. You have
>misinterpreted my words and seem to have totally missed
>the concepts of failure tolerant design. You
>demonstrated a lack of understanding of many simple
>You've also misstated simple facts. You've yet to demonstrate
>the need for supplying folks with the most universal
>concepts in the discipline being discussed.
>I don't think it's helpful to offer designs that depend
>on selection of a particular brand and part number of
>an alternator (which you have yet to identify).
Bob their you go again with the Bob-bastics and bombastic comments
YOU HAVE FAILED TOO....
YOU HAVE MISSED THE POINT
BOAT SAILED YOU WEREN'TT ON IT
YOU LACK UNDERSTANDING OF SIMPLE IDEAS, SIR.
YOUR CUSTOMERS, YOU AND VAN ARE IGNORANT
On size does not fit all. I work with fail-safe Cat III landing procedures, system
fault isolation manuals on transport category Jets. I am responsible for 180
min ET OP operations (long over water flights) and fully understand systems
and their relation to flight safety. You think if someone does not agree they
can't understand the brilliance of your crow bar or grasp the idea of redundancy
or passive failure Geeeeeee. I do understand.
Dont scare people with sensationalized rhetoric. That is a cheap game plan for
someone who likes to be thought of as a benevolent impartial teacher and engineer.
No rocket science, just basic DC circuits 101. How can you not understand
that? It is not as complicated as you like people to believe. EVERY ONE KNOWS
BOB CAN'T RECOMMEND THE ND ALTERNATOR. OK. YOU WIN, I AM WRONG.
>Put any name on it you wish sir, but it doesn't change the
>out come.
Yea I have a name for it.
>I'm reminded of the words of a wise philosopher who stated
>"When the best-you-know-how-to-do is compromised to
>Placate those who would offer anything less, only less-
>than-the-best wins." Please fly your airplane in good
>health but I must continue to base my recommendations on
>the best I know how to do whether or not you understand
>or embrace it.
>There Bob . . .
Well, I am reminded of two words right now myself.
I am not trying to compromise your best, be placated by you or offer anyone less
of anything. What does that mean anyway? It is silly. I am not offering anything.
I never wanted you or need you to change your recommendations Bob.
Take Care Bob
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Bob
| Subject: | Re:Real data on OVP/etc (disinterested?) |
Bob
--> AeroElectric-List message posted by: Gerry Holland <gholland@gemini-resourcing.com>
> I am not trying to compromise your best, be placated by you or offer anyone
> less of anything. What does that mean anyway? It is silly. I am not offering
> anything. I never wanted you or need you to change your recommendations Bob.
> Take Care Bob
So based on an earlier comment in this diatribe........
> Bob dont be mystified. That is so condescending. What I wrote was so
> bewildering, you became disorient and confused. Wow I did not know my words
> had the power to mystify. No one is proposing a panacea here Bob and were are
> a lot smarter than you give us credit for.
What was all that about! and what caused it?
There is enough condescension here to make a person sick.
Do us a favour and the bandwidth on this subject.... summarise it or go for
a long walk!
Do not archive .....it just isn't worth it!
Gerry Holland
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