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darinh

Joined: 20 Apr 2006
Posts: 327
Location: Utah

Posted: Sun Jul 06, 2008 9:35 pm Post subject: Nippondenso alternator question

This is my last question...at least for tonight.  I have a Rotax 914 and the onboard generator is not enough so I added a optional 40 amp nippondenso alternator.  It has the alt. output and a plug labeled "L" and "IG".  I assume the "IG" is the field circuit and the "L" is obviously the lamp circuit.  



The question is this:  I have been told that the alt. must have the indicator lamp installed for it to charge the battery.  I don't really want to add another "idiot" light to my panel as I already had two for the turbo control unit and one for my GRT EIS.  Can I run it through the EIS light or will this screw it up?  If I have to have a light, I may just mount it behind the panel.  Lastly, I was told this light cannot be an LED...is this also correct?

_________________
Darin Hawkes
Series 7
914 Turbo
Kaysville, Utah

info(at)mtfind.com
Guest

Posted: Mon Jul 07, 2008 6:22 am Post subject: Nippondenso alternator question

Depends on the specific ND alternator. The ones I have experience with have

a switch (internal to the regulator) that provides a ground at the "L"

terminal where (in automobiles) an "Idiot Light" is connected across the "L"

to the"IG" and indicates the alternator is getting power to the "IG terminal

but the Alternator's "B" lead Voltage is not high enough to charge the

battery. The ground is removed (and the light goes out) when the alternator

starts supplying power. There are apparently some ND alternators that use

the "L" terminal to power the internal regulator and in that case the "L"

must have a specific light connected to provide starting voltage. In that

case the light is powered by the regulator current before the power from the

"B" lead takes over and the light goes out indicating the alternator is

working properly. I have never seen that type of ND alternator but there are

a few people on other groups who state the Light is required or the

alternator will not provide power. If your alternator requires a light it

should be the light specified in the original application. This provides the

proper current to the regulator.



The only ND alternators I have data for shows the "L" terminal as a simple

switch to ground and personal testing shows the alternator can be turned on

and off while running with no connection to the "L" lead (simply switching

power to the "IG" connection. Turning the alternator off under power is not

recommended as that causes an alternator "load dump" which may damage the

alternator if its disconnected under higher amp charging current. Hasent

happened to me up to a tested 40 amp load dump but still to be avoided

except when the alternator regulator fails high "B" terminal voltage. The

addition of a transorb of sufficient power will shunt the load dump and

protect the alternator but that is a different topic.



ND alternators come in many versions of internal regulators, some sense the

charging voltage thru the IG terminal to accurately charge the battery based

on the battery terminal voltage not the "B: lead voltage.



Thus as originally designed for auto use, the "B" lead is hard wired

directly to the battery. The IGN switch is turned on before starting and the

"idiot light" is powered by the "IG" power input and the regulator internal

ground. There is no requirement for the "L" terminal to be connected to

anything (at least with the ND alternators I have evaluated). If there is a

connection it must limit the current as the internal ground switch may

require external current limiting. In an aircraft application generally

there is no need for any connection to the "L" terminal as the alternator

wiring and its current generation is monitored in a different method. Be

sure your design provides a connection to the battery before starting the

engine.



Sorry but perhaps the supplier of the alternator can tell you. If you

purchased the add on alternator as a specific Kit for your engine. In any

event If the light is required you must install the proper one. Do not

connect the "L" terminal to any thing else other than the proper bulb. Not

an LED as if a light is required the LED with limiting resistor will not

pass enough current and clearly nothing else. If the light is not required

(my personal experience its not) then there is no need if you have other

ways to tell if the alternator is functioning properly like current monitor

or bus voltage. The ND alternator generally requires approx 1500 alternator

RPM to start generation. In an automobile this  is generally around the just

above idle rpm of the engine and again in an auto the idiot light can turn

on at slow idle and go out just above that rpm.



Paul





---

nuckolls.bob(at)cox.net
Guest

Posted: Wed Jul 09, 2008 1:36 pm Post subject: Nippondenso alternator question

At 10:35 PM 7/6/2008 -0700, you wrote:

 	  Quote: 	
		  



This is my last question...at least for tonight.  I have a Rotax 914 and 

the onboard generator is not enough so I added a optional 40 amp 

nippondenso alternator.  It has the alt. output and a plug labeled "L" and 

"IG".  I assume the "IG" is the field circuit and the "L" is obviously the 

lamp circuit.



The question is this:  I have been told that the alt. must have the 

indicator lamp installed for it to charge the battery.


	


   Some do, some don't try it without and if the alternator doesn't come

   on line, hook a 100 ohm, 1w resistor between "L" and "IG". The IG

   terminal is a control lead only that will tell the alternator to come

   on line when +12 is applied to the terminal and assuming the alternator

   is spinning. Again, depending on the whims of the designers of the

   regulator, REMOVING voltage from IG may or may not turn the alternator

   OFF.  You'll just have to try it an see how your particular

   device operates.



 	  Quote: 	
		     I don't really want to add another "idiot" light to my panel as I 

 already had two for the turbo control unit and one for my GRT EIS.  Can I 

 run it through the EIS light or will this screw it up?  If I have to have 

 a light, I may just mount it behind the panel.  Lastly, I was told this 

 light cannot be an LED...is this also correct?


	


   Use the resistor crimped right into the spade terminals

   at the back of the alternator.



   Bob . . .

        ----------------------------------------)

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

        ----------------------------------------

nuckolls.bob(at)cox.net
Guest

Posted: Wed Jul 09, 2008 1:37 pm Post subject: Nippondenso alternator question

At 07:17 AM 7/7/2008 -0700, you wrote:

 	  Quote: 	
		  



Depends on the specific ND alternator. The ones I have experience with have

a switch (internal to the regulator) that provides a ground at the "L"

terminal where (in automobiles) an "Idiot Light" is connected across the "L"

to the"IG" and indicates the alternator is getting power to the "IG terminal

but the Alternator's "B" lead Voltage is not high enough to charge the

battery. The ground is removed (and the light goes out) when the alternator


	


   <snip>



 	  Quote: 	
		  or bus voltage. The ND alternator generally requires approx 1500 alternator

RPM to start generation. In an automobile this  is generally around the just

above idle rpm of the engine and again in an auto the idiot light can turn

on at slow idle and go out just above that rpm.



Paul


	


  There's much good data in this posting . . . enough to give it

  some credibility . . . but some absolute errors too. This has

  been discussed many times in the past and I won't spend any

  more time on it now. Suggest interested readers search the

  articles on the website and the archives on the List server.



  Disinterested readers should disregard the posting in

  its entirety.



  Bob . . .



        ----------------------------------------)

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

        ----------------------------------------

info(at)mtfind.com
Guest

Posted: Wed Jul 09, 2008 5:50 pm Post subject: Nippondenso alternator question

I agree that its been much discussed in the past however there are many 

false and remaining incorrect mis stated comments in the past that simply do 

not apply to the most common ND alternator. These false statements remain in 

the past unchallenged but still remain not correct with respect to ND 

alternators.



Other than MY having tested many ND alternators as well as a couple of other 

brands of Internally regulated Japan brand alternators .I question your 

accusation that I have made absolute errors (or any errors of any sort) in 

my statements.



For example, all the ND alternators I have tested can be turned on and off 

while running and producing power. They also can be "B" lead disconnected 

under load with no damage to the alternator IF the alternator contacts are 

rated properly ( the common often used contactor are not rated to disconnect 

the load dump voltages). The addition of the proper contact voltage and 

proper power rated transorb is required to protect any low voltage contactor 

from arcing and passing the higher load dump voltage back to the bus. The 

subject alternators have internal transorbs but may overheat under the long 

contact bounce of the common contactor, in particular if that contactor has 

a diode across the coil which extends the opening or the contact from around 

5ms to as long as 50 ms with, in several cases, major arcing of dozens of 

arc pulses. Using the industry recommended transorb across the contactor 

coil minimizes the arcing and opening delay but does not resolve the contact 

voltage rating which is overstressed and demonstrated to arc during my 

testing. Its one of the repeatable tests that ranged from 2 amps to 40 amps 

load



I have performed  100's of repeatable tests to support the analysis of the 

above statements including the contact arcing under load of the common 

contactor.. As well as fast opening and lack of arcing with the Kilovac in 

"B" lead testing



My findings include ND alternators commonly used at the time by NSI, Vans 

and others in the mid 1990's have the following features.



1. The IG terminal turns on and off the alternator under load.

Note Its safe as far as the alternator is concerned to turn off the 

alternator under load. It must be done with properly rated contactors 

however.



2, I have been unable to cause alternator failure even with arcing "B" lead 

contactor. Both NSI and Vans at the time was selling rebuilt alternators and 

Vans told customers not to use any type of "B" lead crowbar device due to 

alternator failure.



Note: This I verified with a personal phone call at the time to Vans. I have 

no evidence to suggest your OVP crowbar was the cause but I do suspect the 

common contactor was a possible cause due to observed excessive contact 

arcing during the extended opening of the contacts due in part to the simple 

diode used and the contactor contact V rating.



3. No ND I tested locked up and could not be turned off at any time safely.



4. No ND required anything connected to the "L" terminal.



Clearly its not possible to test all of the hundreds of types of small shell 

ND alternators. Further rebuilt alternators may have internal regulators 

with difference performance as our application has the alternator wired 

differently and the aftermarket rebuilt alternators may have regulators that 

only work when installed in an automobile as the original application.



5. Its safe to open the "B" lead under load if the contactor is rated for at 

least 200V contact rating. Only the KIlovac and similar HV contactors have 

proper voltage ratings. The common contractors for 12V system battery and 

starter etc have contacts only rated for under 50V max during the opening 

process. They can tolerate higher voltage across the contacts when the 

contacts are open. They will arc during the opening of an alternator load 

and the result may cause damage to both the alternator and aircraft bus.



Do not use a common diode across a common contactor coil and do not use a 

common 45V contactor contact rating as either or both actions greatly 

increase of alternator damage



Perhaps you can substantiate your statements with some of your testing of 

the commonly used ND alternator. Please provide the Lester number so we all 

can verify your test results.



My reply to the questioner was intended to be general as he did not state 

the exact ND Lester number and was it rebuilt or new. With out knowing that 

there is no absolute recommendation on how to wire it up



Yes there are alternators of different brands (and perhaps some ND do also, 

but not the common ones that I have tested.) that lock up and others that 

require a lamp in the wiring to start. perhaps there are also other that 

cannot survive a load dump but none in the industry will state that their 

regulators lack the universal load dump internal protection (except that 

load dumps resulting form extended arcing from contacts or broken wiring are 

not protected as overheating or the protection Transorb is possible.



Your cheep un-substantiated comment  that I  have made absolute errors does 

not suit your normally nice style. Lets keep the discussion technical and 

not call me a person making false statements please.



No respectable person can let that cheep shot pass. If I made a error please 

prove it. How many stock ND alternators used in aircraft have you tested???? 

Perhaps I missed it in the past and if so I apologize if you show me the 

statement. It has been more than 10 years ago when many of my testing was 

done and perhaps My memory has failed. To me the discussion on this years 

ago was long settled with you on one side and Jet Pilot George (for one) on 

the other side.



As  side comment many regulators have a OVP built in that limits the output 

voltage to around 16V. This will not protect against all failures thus an 

external OVP is required. I have experienced 2 regulator failures (over the 

past 50 years in autos where the output jumped from 14+ to 16V and held the 

output there. One was the common external regulatro YOU long have 

recommended as a low cost "ford" style.



Please do not reply and waste bandwidth and all of our time unless you have 

specific test data to prove your response. Past history posts that do not 

include backed up with actual testing ase just opinion and not worth 

considering.



Paul



PS: I do not want to start another often widening discussion. Perhaps I 

should have remained silent but you stated you were out of town and I have 

had a lot of experience including some from other groups (who in error) make 

general statements that ND alternators require a light across the IG and L 

connections. Further I have had the impression you have yet to test any 

internal ND or any other brand alternator. This was to be done after you had 

the test stand up and running.



I have witnessed and peer reviewed test setup and test results to support 

the above statements. Only the conclusions have ever been document as I felt 

at the time there was no reason to do more than I did. I simply am not 

interested in trying to prove anything to anything just pass on real test 

results that proved how the auto internal reg alternator can be safely used.





---

darinh

Joined: 20 Apr 2006
Posts: 327
Location: Utah

Posted: Wed Jul 09, 2008 11:47 pm Post subject: Re: Nippondenso alternator question

Thanks guys for the input...mine works without the lamp or the lamp circuit altogether.

_________________
Darin Hawkes
Series 7
914 Turbo
Kaysville, Utah

nuckolls.bob(at)cox.net
Guest

Posted: Thu Jul 10, 2008 7:55 am Post subject: Nippondenso alternator question

At 06:45 PM 7/9/2008 -0700, you wrote:




I agree that its been much discussed in the past however there are many 

false and remaining incorrect mis stated comments in the past that simply 

do not apply to the most common ND alternator. These false statements 

remain in the past unchallenged but still remain not correct with respect 

to ND alternators.



   Okay. I do appologize. Forgive me for assuming too

   much. Please allow me to back up and start anew . . .

Other than MY having tested many ND alternators as well as a couple of 

other brands of Internally regulated Japan brand alternators .I question 

your accusation that I have made absolute errors (or any errors of any 

sort) in my statements.



For example, all the ND alternators I have tested can be turned on and off 

while running and producing power. They also can be "B" lead disconnected 

under load with no damage to the alternator IF the alternator contacts are 

rated properly ( the common often used contactor are not rated to 

disconnect the load dump voltages). The addition of the proper contact 

voltage and proper power rated transorb is required to protect any low 

voltage contactor from arcing and passing the higher load dump voltage back 

to the bus.



   Do you have schematics that describe the test setup along

   with materials callouts and a description of test conditions

   that you can share with us for an exemplar test?



  The subject alternators have internal transorbs but may overheat under 

the long contact bounce of the common contactor, in particular if that 

contactor has a diode across the coil which extends the opening or the 

contact from around 5ms to as long as 50 ms with, in several cases, major 

arcing of dozens of arc pulses. Using the industry recommended transorb 

across the contactor coil minimizes the arcing and opening delay but does 

not resolve the contact voltage rating which is overstressed and 

demonstrated to arc during my testing. Its one of the repeatable tests that 

ranged from 2 amps to 40 amps load.



   I have tested, documented and published tests results

   that illustrate my findings with respect to various

   arc suppression methodologies for relays and contactors.

   The increased contact drop out delay for the most agressive

   arc suppression technique (plain diode) was predictable

   and demonstrated in every test. However, contact spreading

   velocity seems to be affected more strongly by spring rates

   and growing air-gaps between coil core and armature. Only

   the slightest slowing of spreading velocity could be

   detected between NO suppression and the most agressive

   suppression. the delta-t was on the order of 2-4 percent.



   From those tests I extrapolated that while the contactor

   was certainly slower to begin opening, it was not significantly

   slower in spreading once the armature became detached

   from the coil core.

I have performed  100's of repeatable tests to support the analysis of the 

above statements including the contact arcing under load of the common 

contactor.. As well as fast opening and lack of arcing with the Kilovac in 

"B" lead testing.



   It's an acknowledged fact that the Kilovac devices

   are a different cat bred for improved performance

   under certain operating conditions. But to avoid

   mixing apples and oranges, I will confine the current

   discussion to more rudimentary devices like those

   suggested in the Z-figures.



   Given the numbers of tests cited, I presume that

   you have data recorded from those tests that illustrate

   your findings? This is where rubber hits the road

   my friend. If your findings differ from my own, then

   there is some variable between our testing conditions

   or philosophy that will explain the differences. As

   teachers, we should KNOW what those variables are

   so that they become part of our stock and trade in

   helping others understand.



   (1) So, the first difference to be resolved is why

   your findings report significant differences in

   arcing between spreading contacts that are dependent

   upon style of arc suppression used.

My findings include ND alternators commonly used at the time by NSI, Vans 

and others in the mid 1990's have the following features.



1. The IG terminal turns on and off the alternator under load.

Note Its safe as far as the alternator is concerned to turn off the 

alternator under load. It must be done with properly rated contactors however.



   I'm confused here. Assuming the IG terminal exerts

   absolute control over the inner workings of the alternator

   then there is no need to utilize an external b-lead

   contactor. Alternators and generators in aircraft

   and other DC systems have been turned on and off under

   ALL conditions of load since day-one by exerting

   positive control over the field current.



   The schematics of all internally regulated alternators

   I've been privileged to review take the IG lead onto

   the integrated circuit chip for the regulator. For

   the astute practitioner of failure mode effects analysis,

   this raises some flags as to the system should be

   designed to DEPEND on functionality of the IG lead

   as an absolute control.  Damage to the chip can

   obviously cause loss of regulation (over voltage)

   but it could also cause loss of absolute control.



   Another variability comes from my interpretation

   of your words that suggest the alternator control

   philosophy you're citing is not unlike that which

   is described in the first schematic of:



http://aeroelectric.com/articles/Adapting_IR_Alternators_to_Aircraft.pdf



   Here, I've assumed that EVEN IF the IG lead

   does exert absolute control over a normally operating

   alternator, it cannot be depended upon to exert

   that control under certain failures of the

   integrated circuit. Augmentation of that control

   is called for in the form of a b-lead disconnect

   device of some suitable design.



   (2) so another clarification of control philosophies

   suggests that EVEN IF the IG lead works as you've

   described in all ND alternators you've tested, would

   you not agree that the same functionality cannot be

   depended upon for other brands? Further, since we

   have no way to guarantee our builder friends that

   every device marked "ND" functions the same way . . .

   ESPECIALLY if overhauled by an after market activity?

2, I have been unable to cause alternator failure even with arcing "B" lead 

contactor. Both NSI and Vans at the time was selling rebuilt alternators 

and Vans told customers not to use any type of "B" lead crowbar device due 

to alternator failure.



Note: This I verified with a personal phone call at the time to Vans. I 

have no evidence to suggest your OVP crowbar was the cause but I do suspect 

the common contactor was a possible cause due to observed excessive contact 

arcing during the extended opening of the contacts due in part to the 

simple diode used and the contactor contact V rating.



   Interesting hypothesis that argues with my own observations

   that generated question (1) above.



3. No ND I tested locked up and could not be turned off at any time safely.



4. No ND required anything connected to the "L" terminal.



   Good data points. but in light of potential for variances

   that prompted question (2) COMBINED with the desire to

   offer a control philosophy that works with ANY brand

   of alternator, would you not agree that a 100 ohm resistor

   tied between "L" and "IG" is a sure bet even if not

   necessary for the particular alternator in-hand?

Clearly its not possible to test all of the hundreds of types of small 

shell ND alternators. Further rebuilt alternators may have internal 

regulators with difference performance as our application has the 

alternator wired differently and the aftermarket rebuilt alternators may 

have regulators that only work when installed in an automobile as the 

original application.



   ABSOLUTELY! This is the exact thinking that drives my

   system design suggestions. The goal is NOT to have my

   readers worrying over all the possibilities for his/her

   particular alternator in-hand but to offer the simplest,

   most universal solution that is free of such worries.

5. Its safe to open the "B" lead under load if the contactor is rated for 

at least 200V contact rating. Only the KIlovac and similar HV contactors 

have proper voltage ratings. The common contractors for 12V system battery 

and starter etc have contacts only rated for under 50V max during the 

opening process. They can tolerate higher voltage across the contacts when 

the contacts are open. They will arc during the opening of an alternator 

load and the result may cause damage to both the alternator and aircraft bus.



   Okay, here's where we need to talk about system conditions

   at time of opening. IF the alternator is being shut down with

   all equipment operating normally (alternator output is under

   control of a functioning regulator) then upward excursions

   of b-lead voltage is limited by the over-shoot response of

   the alternator/regulator combination if the alternator is

   under load at time of disconnect.



   (3) The next question goes to the magnitude, duration and

   energy contained in the transient event of a suddenly

   unloaded alternator. The magnitude of these numbers are

   CRITICAL to understanding the energy that either needs to

   be stood off (by sizing of clamping devices like transorbs)

   or withstood (by sizing circuit breaking capabilities of

   the b-lead contactor). With the testing you've accomplished,

   have you quantified this event and can you share that data?

Do not use a common diode across a common contactor coil and do not use a 

common 45V contactor contact rating as either or both actions greatly 

increase of alternator damage.



   (4) This raises some flags. Exactly how does the arcing

   across the spreading contacts of the b-lead disconnect

   device stress the alternator? The arc is a sustained (if

   not smoothly varying) current that is no greater than

   the alternator is rated to deliver. I think we can agree

   that the voltage available is no greater than the magnitude

   of over-shoot transients which I presume you've sized and

   can describe in question (3).

Perhaps you can substantiate your statements with some of your testing of 

the commonly used ND alternator. Please provide the Lester number so we all 

can verify your test results..



   As I mentioned in earlier posts, I try to craft design

   philosophies that are NOT constrained by selection of

   specific parts. My design goals are (A) craft the simplest,

   lowest cost of ownership, failure tolerant system. (B)

   deduce ways in which the widest selection of components

   can be utilized IRRESPECTIVE of their internal operating

   differences.



   For me, this discussion has never been about the deifying

   the ND products or vilifying any other product. It's been

   about deducing ways that my readers can use any alternator

   they choose. When this goal is achieved, the greatest

   concern for selection is that the thing might be a piece

   of junk . . . but it doesn't matter because we've designed

   a system that if failure tolerant. I.e., ALL failures are

   a maintenance expense, not a safety issue.

My reply to the questioner was intended to be general as he did not state 

the exact ND Lester number and was it rebuilt or new. With out knowing that 

there is no absolute recommendation on how to wire it up.



    . . . and I'll suggest that my response for the resistor

   was a universally applicable approach that didn't care

   about make, model, or functionality of the alternator.



Yes there are alternators of different brands (and perhaps some ND do also, 

but not the common ones that I have tested.) that lock up and others that 

require a lamp in the wiring to start. perhaps there are also other that 

cannot survive a load dump but none in the industry will state that their 

regulators lack the universal load dump internal protection (except that 

load dumps resulting form extended arcing from contacts or broken wiring 

are not protected as overheating or the protection Transorb is possible.



   (5) This gives rise to the next question that goes to

   the un-quantified "extended arcing". Folks in industry

   a fond of talking about such things without numbers that

   allow a system integrator to artfully integrate their

   products into a consumers system. You have repeated the

   phraseology without quantification. It's my goal that

   my partner in Douglas-Nuckolls LLC will help me get this

   critter  . . .



http://aeroelectric.com/Pictures/Alternator_Test_Stand/Alternator_Test_Stand_1.jpg



   up and running so that I can expand my personal knowledge

   of these questions that have been CRITICAL details of alternator

   discussions on this List for 10 years. To date they've

   NEVER answered by anyone. If you have access to this

   kind of equipment and test articles right now, then

   I'll suggest you are in the very best position to advance

   the state of our art and the quality of our discussions

   to the benefit of anyone interested in reading them.

Your cheep un-substantiated comment  that I  have made absolute errors does 

not suit your normally nice style. Lets keep the discussion technical and 

not call me a person making false statements please.



   Agreed. I let my frustrations with another matter

   bleed over into my work on this List. Explainable

   but not excusable. I beg your indulgence.



No respectable person can let that cheep shot pass. If I made a error 

please prove it.

How many stock ND alternators used in aircraft have you tested????



    My concerns come from the notion that every device

    having the ND logo on it is "stock" or "golden"

    . . . especially when we know NOTHING about the pedigree

    of the alternator in question and even less about how

    the regulators are crafted.



Perhaps I missed it in the past and if so I apologize if you show me the 

statement. It has been more than 10 years ago when many of my testing was 

done and perhaps My memory has failed. To me the discussion on this years 

ago was long settled with you on one side and Jet Pilot George (for one) on 

the other side.



    Describe "sides" . . . my antagonists basically

    offered the notion that everything ND was golden

    substantiated by nothing more that marketing hype.



    I have personally tested NO internally regulated

    alternators. ALL of my work with aircraft alternators

    and generators has been done on the legacy products

    that prevail in type-certificated aircraft. I'm moving

    toward the capability to test such devices as noted

    above because the data I need for artful design is

    has not been forthcoming from other sources. Perhaps

    you can assist.



    (6) There is one more case for alternator control

    that involves understanding how to handle the

    fully-excited runaway condition with an external

    b-lead contactor . . . but this is a special case

    that begs a separate discussion. For now, if you

    could share what you know that goes totward (1)

    through (5) I'd be more pleased than you can know.

As  side comment many regulators have a OVP built in that limits the output 

voltage to around 16V.



    That claim has been made before . . . and in one discussion,

    a reader suggested that when a pilot experienced an

    ov condition (that puffed up his battery and zorked a

    number of ship's accessories) that the ov condtion

    had to have been limited to something on the order

    of 16 volts. I presume this statement came from an

    interpretation of marketing hype for a particular

    product . . . with no guarantees that the failed device

    in the guys's airplane had the same feature.



    I've often cited the dearth of real data on internally

    regulated alternators. This device has been cited

    many times in discussions here on the List.



http://aeroelectric.com/Mfgr_Data/Semiconductors/MC33092A.pdf



    This is the ONLY hard copy of an internal regulator

    design I've been privileged to study. If you trace through

    the functionality of this device, you'll discover that

    there is OV warning, but no OV protection. Is this

    20+ year old device a good example of what's available

    today? Who knows? If anyone does know, it has not been

    shared here on the List.



    Given the lack of information, I have to proceed with

    worst case assumptions that treat the built in regulators

    with no more reverence than external regulators

    of yesteryear . . . hence failure tolerant no matter

    what.



    If we DID have detailed data on ANY brand and part number

    of alternator/regulator . . . it would be of little value

    to me as purveyor of universally applicable advice. It's

    not my goal to help Joe rivet-bucker integrate a particular

    part into his system . . . the goal is to offer ways he

    can integrate any part with some reasonable sense of confidence

    in failure tolerant design.



  This will not protect against all failures thus an external OVP is 

required. I have experienced 2 regulator failures (over the past 50 years 

in autos where the output jumped from 14+ to 16V and held the output there. 

One was the common external regulatro YOU long have recommended as a low 

cost "ford" style.



    The "ford" style has never been a consistently performing

    product. The first pass at this design was this

    critter . . .



http://aeroelectric.com/Pictures/Regulators/Ford_EM_Reg.jpg



    Pure electro-mechanical. No OV protection. I designed the

    first OV protection module . . .



http://aeroelectric.com/Pictures/Schematics/Cessna_OVModule.gif



    that was applied to this regulator at Cessna many moons

    ago.



    Over the years, the EM regulators were replaced with

    solid state devices from a number of suppliers including

    Ford and typical of this package . . .



http://aeroelectric.com/Pictures/Regulators/Ford_SS_Reg.jpg



http://aeroelectric.com/Pictures/Regulators/Ford_SS_Reg_open.jpg



    At this point, features and functionality from model to

    model begins to diverge. I've seen them offered with

    over current and over voltage protection built in . . .

    but with no definitive descriptions of how those features

    worked. I.e., no way that the prudent aircraft systems

    designer can accomplish FMEA and deduce suitability to

    the task. Therefore, in satisfaction of my goal for

    universally applicable advice, I assume that ALL such

    devices are applicable to my designs if augmented with

    OV protection of predicable functionality illustrated in

    the Z-figurs.

Please do not reply and waste bandwidth and all of our time unless you have 

specific test data to prove your response. Past history posts that do not 

include backed up with actual testing ase just opinion and not worth 

considering.



    I will request the same courtesy from you and I've

    cited the items of divergence/confusion above. I have

    provided detail process and numerical data on every

    experiment I've conducted. It's my intent to gather

    the data we all need, everyone talks about but nobody

    possesses or has shared if they do possess it. Toward

    this goal, no amount of bandwidth is wasted.

Paul



PS: I do not want to start another often widening discussion. Perhaps I 

should have remained silent but you stated you were out of town and I have 

had a lot of experience including some from other groups (who in error) 

make general statements that ND alternators require a light across the IG 

and L connections. Further I have had the impression you have yet to test 

any internal ND or any other brand alternator. This was to be done after 

you had the test stand up and running.



   The discussion will be no wider than necessary to

   achieve an understanding of how internally regulated

   alternators function to the degree that we can craft

   the most universal techniques for using them.



I have witnessed and peer reviewed test setup and test results to support 

the above statements. Only the conclusions have ever been document as I 

felt at the time there was no reason to do more than I did. I simply am not 

interested in trying to prove anything to anything just pass on real test 

results that proved how the auto internal reg alternator can be safely used.



    We can TALK about tests until you-know-where freezes

    over but none of this talk has universal value until

    the simple-ideas of the physics and magnitude of effects

    are documented and shared. Critics of movies and restaurants

    can wax eloquently about their favorite topics . . . and

    some individuals find value in reading their words. You

    and I are on the other side of the stove where understanding

    exactly what and why ingredients go into a recipe for success

    is critical to understanding.



    Kindest regards,



    Bob  . . .

info(at)mtfind.com
Guest

Posted: Thu Jul 10, 2008 9:31 am Post subject: Nippondenso alternator question

[quote] THANK YOU for your very nice reply!!



 Please bare  with me as the data I have is long many years filed away 

 and will be hard to resurrect  a lot of it other than my conclusions.



 The results were so clear to myself and several other local peers as well 

 as Eric (on the east coast) I simply pressed on. I had no intent to come 

 up with a universal solution when the specific ND type was discovered to 

 meet what my group felt was a reasonable recommendation. Low cost, small 

 and light weight, readily available, and 50-55 amp output which fit most 

 applications including LYC and most popular auto engine conversions.



 I will try to provide information to discuss one part at a time as this 

 email includes a large range of subjects and can end up being 1,000 lines 

 long and too long for others to follow. Thus it may take as many as 8-10 

 different subject strings to cover each subject area



 I have specific experience (including test stand load tests up to 40 amps 

 load) with several types of ND alternators which are different in several 

 respects. Its clear to me that blessing all ND alternators as suitable is 

 not true. I also have some experience with two brands of alternators. 

 These were as I recall MI and HI brands??. I need to look up details as 

 they had undesirable design features (at least to me) like requiring a 

 lamp and or locking up. Also the reported failure rate in autos was of 

 concern. I do not agree that the objective of one solution fits all 

 brands/types is a reasonable solution but good luck. With my research 99% 

 of internal reg alternators are ND and of the hundreds of types of ND 

 available only a couple types are used in any quantity. Thus I settled on 

 one brand ND and one type for general use. Today there is a second ND Type 

 that is slightly larger and heavier that is 80-90 amp output that might be 

 a better choice for the more complex OBAM being today.



 In any event its now my turn to start one subject at a time in replying to 

 your comments and questions.



 Paul





 ---

sportav8r(at)gmail.com
Guest

Posted: Thu Jul 10, 2008 10:03 am Post subject: Nippondenso alternator question

Now THIS I'm looking forward to, not with blood-lust, but just the anticipation that we are going to _get somewhere_ as  an OBAM community on this lightweight IR alternator issue, with confidence and without too much frustration.  Many others, I suspect, are like me - not wanting to do the lab research but certainly to understand the research of others, and waiting patiently for a turn-key solution that works for our planes with a minimum of fuss and procurement headaches.

 

Play nice, gentlemen.  The students are watching 



-Bill B



On Thu, Jul 10, 2008 at 1:28 PM, Paul <info(at)mtfind.com (info(at)mtfind.com)> wrote:

[quote] --> AeroElectric-List message posted by: "Paul" <info(at)mtfind.com (info(at)mtfind.com)>

 

 [quote] THANK YOU for your very nice reply!!

 

 Please bare  with me as the data I have is long many years filed away and will be hard to resurrect  a lot of it other than my conclusions.

 

 The results were so clear to myself and several other local peers as well as Eric (on the east coast) I simply pressed on. I had no intent to come up with a universal solution when the specific ND type was discovered to meet what my group felt was a reasonable recommendation. Low cost, small and light weight, readily available, and 50-55 amp output which fit most applications including LYC and most popular auto engine conversions.

  

 I will try to provide information to discuss one part at a time as this email includes a large range of subjects and can end up being 1,000 lines long and too long for others to follow. Thus it may take as many as 8-10 different subject strings to cover each subject area

  

 I have specific experience (including test stand load tests up to 40 amps load) with several types of ND alternators which are different in several respects. Its clear to me that blessing all ND alternators as suitable is not true. I also have some experience with two brands of alternators. These were as I recall MI and HI brands??. I need to look up details as they had undesirable design features (at least to me) like requiring a lamp and or locking up. Also the reported failure rate in autos was of concern. I do not agree that the objective of one solution fits all brands/types is a reasonable solution but good luck. With my research 99% of internal reg alternators are ND and of the hundreds of types of ND available only a couple types are used in any quantity. Thus I settled on one brand ND and one type for general use. Today there is a second ND Type that is slightly larger and heavier that is 80-90 amp output that might be a better choice for the more complex OBAM being today.

  

 In any event its now my turn to start one subject at a time in replying to your comments and questions.

 

 Paul

 

 

 

 

 ---

nuckolls.bob(at)cox.net
Guest

Posted: Thu Jul 10, 2008 12:39 pm Post subject: Nippondenso alternator question

At 10:28 AM 7/10/2008 -0700, you wrote:

 	  Quote: 	
		  



>THANK YOU for your very nice reply!!

>

>Please bare  with me as the data I have is long many years filed away 

>and will be hard to resurrect  a lot of it other than my conclusions.

>

>The results were so clear to myself and several other local peers as well 

>as Eric (on the east coast) I simply pressed on. I had no intent to come 

>up with a universal solution when the specific ND type was discovered to 

>meet what my group felt was a reasonable recommendation. Low cost, small 

>and light weight, readily available, and 50-55 amp output which fit most 

>applications including LYC and most popular auto engine conversions.


	


   Understand . . . and from the perspective of

   needing to design a product, one needs to

   be much more specific as to the numbers that

   appear on a bill of materials . . .

 	  Quote: 	
		  >I will try to provide information to discuss one part at a time as this 

>email includes a large range of subjects and can end up being 1,000 lines 

>long and too long for others to follow. Thus it may take as many as 8-10 

>different subject strings to cover each subject area

>

>I have specific experience (including test stand load tests up to 40 amps 

>load) with several types of ND alternators which are different in several 

>respects. Its clear to me that blessing all ND alternators as suitable is 

>not true. I also have some experience with two brands of alternators. 

>These were as I recall MI and HI brands??. I need to look up details as 

>they had undesirable design features (at least to me) like requiring a 

>lamp and or locking up. Also the reported failure rate in autos was of 

>concern. I do not agree that the objective of one solution fits all 

>brands/types is a reasonable solution but good luck.


	


   Not so much a dependence on good luck but a degree

   of protection from bad luck. Too many of the dark-n-stormy-night

   stories on electrical system issues demonstrate a gross lack

   of understanding on the part of pilots and an unimpressive

   demonstration of design goals on the part of TC aircraft

   manufacturers for failure tolerant design. But given that aircraft

   and medicine are probably the two most regulated industries

   in our nation, we need only look to those to craft law to

   understand why these industries are ham-strung.



   Given the millions of alternators and many dozens of brands/styles

   on the road that provide good service, it's not unreasonable to

   suggest that an OBAM aircraft owner has a huge pallet of colors

   from which to paint their electrical system. Risk for a bad choice?

   Sure . . . but relatively low. Especially If we can prevent a bad

   choice from becoming a safety issue.



   Now, if any individual has a product performance report to share

   with other builders that suggests a good value, that's fine with

   me but outside my mission. I don't work in a venue where I can

   recommend choices among alternators, switches, engines, tires,

   instruments, upholstery materials, etc. But I CAN craft architectures

   that minimize cost of ownership, weight, parts count and RISK.



 	  Quote: 	
		  >  With my research 99% of internal reg alternators are ND and of the 

> hundreds of types of ND available only a couple types are used in any 

> quantity. Thus I settled on one brand ND and one type for general use. 

> Today there is a second ND Type that is slightly larger and heavier that 

> is 80-90 amp output that might be a better choice for the more complex 

> OBAM being today.


	


   An your selection for your application is probably the

   ideal fit to your design goals. For customers to are

   willing to pay my outrageous fees, I'm equally specific.

   But for the folks who hang out on this List, I don't

   want to close any doors and windows for parts selection

   except where there is perceived increases in risk.

 	  Quote: 	
		  >In any event its now my turn to start one subject at a time in replying 

>to your comments and questions.


	


    Looking forward to a productive exchange of ideas!



    Bob . . .

rampil

Joined: 04 May 2007
Posts: 870

Posted: Thu Jul 10, 2008 2:48 pm Post subject: Re: Nippondenso alternator question

Gee, 

Has anyone thought to go to http://www.globaldensoproducts.com/em/a/

Root around and get actual information about their specific model

alternator from their library?

I got the info I needed on the specs of my aux ND alternator derived

from the 3 cyl Geo Metro.

_________________
Ira N224XS

Bill Schlatterer

Joined: 09 Jan 2006
Posts: 195

Posted: Thu Jul 10, 2008 6:02 pm Post subject: Nippondenso alternator question

Paul, just for grins  do you have a part number (industry or particular

brand) that you are recommending or suggesting as a good place to start?  Or

a specific automotive application.  I keep hearing the 50-60 ND is the one

but ,... Which one?



Thanks Bill S

7a finishing 



--

info(at)mtfind.com
Guest

Posted: Thu Jul 10, 2008 8:11 pm Post subject: Nippondenso alternator question

---

nuckolls.bob(at)cox.net
Guest

Posted: Sat Jul 12, 2008 4:57 pm Post subject: Nippondenso alternator question

At 10:28 AM 7/10/2008 -0700, you wrote:

 	  Quote: 	

>THANK YOU for your very nice reply!!

>

   <snip>

 	  Quote: 	
		  >In any event its now my turn to start one subject at a time in replying 

>to your comments and questions.

   Paul, how about we avoid turning this into an unnecessary and/or

   unproductive research/science project . . . It would be useful to

   craft a sort of mission statement where goals, impediments to

   goals, questions and plans for acquiring data that go to aswering

   those questions are identified up front. To that effort I'll offer

   the following:

   1) Since day-one, electrical systems in aircraft have offered

   a means by which engine driven power sources may be turned on

   and off at will of the pilot. This absolute ON/OFF control goes

   to a number of issues that include but are not limited to

   preflight testing, load management, ability to take a mis-behaving

   system off line, and plan-B activities crafted to mitigate

   effects of failure. I.e., failure tolerance.

   2) The modern automotive alternator has a proven track record

   in ground based vehicles that eclipses anything flying

   by an order of 1000:1 or more.  It's inarguable that sources

   of automotive components from salvage yards up through the

   chain to manufacturers of modern components offer the OBAM

   aircraft community a treasure-trove of choices.

   3) The shear magnitude of choices can be a boon in terms

   of potential return on investment for performance and

   reliability . . . and a bane in terms of the complexity

   for choosing "suitable" hardware from an overwhelming

   universe of products and sources.

   4) As knowledgeable and experienced practitioners of the

   art and sciences we can relieve OBAM aircraft owner/operator

   concern for making choices while minimizing risk for having made

   a "bad" choice?  I'll have to qualify "bad" . . . EVERY

   piece of hardware we choose to bolt to an airplane will fail

   at some point in time irrespective of its source or perceived

   quality. Failure can be due to quality issues . . . operation

   outside design limits . . . or the thing simply wears out.

   5) My personal preference for minimizing risk is to craft

   failure tolerant architectures . . . if we do

   that job well, then it doesn't matter if the platinum

   plated part fails because some kid didn't tighten a

   bolt (quality issue). . . or failed because the part is

   one step above junk (design or manufacturing issue).

   Failure tolerance is the most powerful tool for risk

   management we can bring to the table.

   6) You appear to be crafting a risk mitigation

   approach along with relief of the decision making process

   in the form of specific architectures crafted from

   specific part numbers. You believe this approach

   is attractive  to potential customers. This is the

   essence of entrepreneurial opportunity in what is

   still (unlike TC aviation) a relatively free marketplace.

   Your approach borrows from the legacies of TC aviation

   by specifying a design and more controlled suite of

   components. No doubt here are/will-be customers

   attracted to this approach and I'm sure we all wish

   you well in your endeavor.  My entrepreneurial leanings

   go to system integration hardware, products that help

   the OBAM aircraft builder comfortably integrate a host

   of choices into the airplane. But first, I need to achieve

   an understanding of the simple-ideas that go into

   our respective inventions . . . ingredients that drive

   recipes for success.

   7) We have a common need to exercise a solid grasp

   of the same simple-ideas even if our respective inventions

   have no competitive features. The most pressing question

   for me is understanding the load-dump characteristics

   of our favorite alternators under conditions likely to

   be encountered in a typical installation on a Lycoming -

   spinning like a whirling dervish and subject to

   unloading under any condition between zero and full

   output with normal regulation. This means knowing the magnitude,

   source impedance and timing of the transient that occurs

   after sudden load removal at all corners of the

   operating envelope.

    The very first experiment I plan to conduct after

   the alternator drive stand is running is based on

   the sketch at:

   On a 60A machine with battery disconnected,

   I'd get data plots of load dumps at 4, 6, 8, 10

   and 12KRPM for fixed load of 50A with a 10A dump,

   fixed load of 40A with 10A and 20A dumps, fixed

   of 30A and 10, 20 30A dumps . . . I think you'll see

   the pattern here.

   The goal would be to calculate/measure the peak

   voltage, total energy and duration of each overshoot

   event (or series of overshoots assuming the regulator

   control loop is poorly damped). I would probably

   set up to run external regulators (of the type

   normally installed inside) so that I could explore

   the differences between various regulators while

   holding the alternator constant.

   Obviously a big task to gather enough data to

   be reasonably sure we understand the majority of

   the fleet . . . assuming we discover wide variances.

   (9) The next tests would involve system behavior under

   runaway conditions. Artificially fail a regulator

   and plot dv/dt at the bus and di/dt at the battery

   with various fixed loads . . . one suite of plots

   with a fresh battery, another with a battery that

   has fallen to 1/2 capacity or less.

   Having this data on only one combination of

   alternator/regulator would set the order of magnitude

   for energies involved. Once the equipment for the

   testing is in place and the procedure tuned, it would

   probably take less than a half hour to test any other

   combination.

   I ran all these tests that supported products I designed

   for Beech and others many moons ago. But the only

   data acquisition we had then were storage 'scopes and

   chart recorders. You could "eyeball" the data for gross

   suitability to task but real energy studies were exceedingly

   difficult . . . they were never done. We can do a much

   better job today.

   The task is to characterize the dynamic response to

   load change for a normally functioning as well as

   a runaway alternator. The data collected would allow

   a designer to craft systems that deal quietly and

   capably with the voltages, currents and energies that

   are present during recovery from both a load-dump

   and hard-failure conditions.

   This was the kind of data I was hoping to gather

   some years back when there was discussion about

   you and Eric teaming on some sort of activity. I

   wasn't sure exactly what equipment you were going to

   have access to . . . or what testing satisfied

   curiosities for your project . . . but I had hopes

   of piggy-backing studies above if you didn't already

   have similar data.

   Do I presume that for your needs, no further

   investigation is necessary/useful to your task?

   Know that all of my own test results will be published

   on aeroelectric.com  and that my equipment will be available

   to you (or anyone else in the OBAM aviation community)

   should new questions arise.

   I'm going to have Zach start stripping out the automotive

   test setup wiring from the test stand next week. We'll

   leave only the 3-phase motor drive wiring intact. We'll

   Z-12 and Z-13/8 architectures in the stand. I already

   have a small drive stand for second alternators up to 20A.

   I have a static phase converter to install in the

   big stand. We'll see we can get the motor and variable

   speed drives to run. That will be a BIG step. Not sure

   if we'll be able to do real testing before we have to

   pack up and move to M.L.  I have a contractor running

   a fat 240 feeder to the shop at the same time we excavate

   for a new retaining wall at the back of the yard. So the

   heavy/dirty/ugly work should be behind us at both

   locations this summer.

   Bob . . .

info(at)mtfind.com
Guest

Posted: Sat Jul 12, 2008 10:02 pm Post subject: Nippondenso alternator question

Well (very sadly but it did seem too good to be true and I am not surprised)

I had hoped for mutual cooperation but I guess you want to do it all your

self. Good timing as I was just finishing the first part of the planned

discussion.



Be my guest, I had thought you had changed. Clearly you want yo frive the

discussion VS get the benefit of my extensive work.



Random comments as its not worth my time to put them in ordered sequence. I

have made some suggestions about how and what to test to avoid missing

information that is not gathered just using your sketched circuit.



You are incorrect about my approach and intent and about my past analysis

and testing which is in my opinion adequate to determine the problem and I

have "crafted" a proven solution. In my opinion there is ZERO need for more

testing other for self aggrandizement. I find this sad as you have not seen

any real results of my testing nor the scope of it. Reading your suggested

approach I find little to agree with so there is no point in my being a part

of your long promised study.



Further most of your below comments about my position are totally incorrect

assumptions which is not surprising as you have never spent the time to find

out what my approach is; the amount of analysis, investigation nor testing

setup and results. I will not tolerate testing as anything other as proof of

pre testing design analysis. I also simply will not design using assumptions

or unofficial verbal assurances from one manufacturer its safe to exceed the

specifications as that is simply a high risk approach no engineer will do.

My results are identical design solution for all reasonable alternator but

clearly its not reasonable to allow any alternator to be covered and that

position indicates to me a lack of modern alternator designs etc. Further

you seem fixated on maintaining several design flexibilities and pilot

control that I feel is not only not required but potentially dangerous.



Also your sketch does not reproduce the real world load dump conditions what

with fixed load and relay contact bounce in the real circuit. Finally it

appears you intend to have a constant string of load dumps which is very

likely to destroy the internal to the regulator load dump protection

components. Each single load dump needs time for the protection circuits to

cool down.



Hopefully you will end up with far more evaluation, studying, and testing

than what you listed below as its not adequate nor has it addressed ALL the

problems I have addressed. You really should test all the brands of

alternators you intend to approve of and in the several different types and

amps in each style. There are differences to consider. For example different

regulator transient response as well as the winding charactericts which will

determine the load dump information.



Further you should take note of the fact just how much (or more important,

how little) is replaced in rebuilt alternators as if you know what is

replaced you would never recommend a rebuilt alternator (rebuilt is a

misnomer minimal repair is what actually happens).Junk yard is not a source

for ANY aircraft as who knows how close to failure the parts are. In any

event testing alone, with out first doing an analysis and manufacturers

detailed data is NEVER sufficient. Both Myself and Jet Pilot found getting

more detailed information was not easy and getting past the sales staff if

difficult at best. However a lot of useful information was passed on and

po-poed on this groups list.



Also be sure to test with a full load current and zero fixed load. Note my

selected 50 amp rated alternator is specified to put out 70 amps at 13V and

more amps at lower voltages so a full output failure results in a much

higher current than your suggested testing which based on my testing is not

nearly worst case! Another comment about getting the real data first. My NEW

alternator came with a computer printout of the actual alternator during

final test prior to shipment. Note the full amp output is a lot higher than

past comments have been clearly assumed on this list in the past. 40% higher

is not small in my opinion and under load dump conditions the load being

dumped is much higher energy as well as the peak voltage. My testing was

based on a real duplication of a typical aircraft wiring including wire

gauge and lengths as well as flight batteries. It started with your OVP and

contactor with the diode on the contactor coil. Very different than what

your sketch shows. Also very long alternator failure point to final

contactor opening requiring voltage clamping during that time of a lot more

energy than what has been assumed in one of your tests from years ago.



But then we have a large and fundamental difference on how to design any

electrical (including aircraft) systems. My approach is to discard many of

the proven pilot opportunities to mess up that have been a reason for past

crashes and leap into the 21st century. Building on the past and not address

the fundamental cause of most accidents is not progress in my opinion. The

more pilot required actions greatly increases the pilots lack or incorrect

action. Today there is no need to do things manually in most cases. Every

manual control available to the pilot 's another opportunity to make a

mistake that can lead to a crash. Today we have Integrated Solid state

switches/circuit breakers. Schottly diodes are not really needed much less

silicon bridges which have no use in aircraft. Yes Solid state switching is

easy to make with full bi-directional isolation and ON resistance less that

of mechanical relays etc switching (as low as 0.002 ohms ON resistance). The

pilot needs to be notified of any CB failure not by finding out by failure

of the component to work for example.



The aircraft instruments have migrated from steam gauges to flat panels yet

we still find the old contactor relay// switch approach of 1950 etc and that

ignores the modern components available today that are far more reliable and

more pilot friendly.



Its a fact that pilot error is the major cause of accidents. Its pilot error

if you run out of fuel, deplete the battery based on an assumption of

battery condition and electrical load etc etc. The requirement to throw a

switch in an emergency is bad design if there is a reasonable solution that

eliminates the mechanical pilot action and its done automatically. Its sad

that there is no truly modern system available at a reasonable price on the

market today that automates the system and provides the pilot with useful

real time electrical system conditions. My designs have been peer reviewed

by my (multiple) peers and all have stated its both more reliable and a

great improvement to current 1950's parts and today's arrangements and

approaches. You have long promoted fly the airplane and trouble shoot back

on the ground which is not what your design requirement to turn on and off

the alternator in flight and a simple voltage check is enough for preflight.

Personal situation has delayed getting my system on the market.



The E bus is a good example where there is a design requirement to have a

group of avionics disabled during part of the flight and then guess about

how much battery life is left. A simple additional electrical instrument I

have designed allows the pilot to simply see the real flight time left and

change the load and have the flight time left update. It also determines the

true battery life dynamically. If I am IFR I may need a different set of

avionics than what is on the E bus for example depending on the actual

flight conditions. Or what if the battery power left at any point is less

that what was predicted or measured months ago?.  I know of several off

field crashes due to the battery being depleted well before the expected

time. Another bad design to assume something in particular when it ns not

required to assume. Fuel tank gauges system when the only accurate

requirement is full and empty has been replaced with fuel flow measurement

and totalized as seen in modern automobiles. No reason the battery cannot be

treated the same way, sure its a little more complex but not hard to do with

reasonable accuracy.



There are many ways to make flying safer than having a check list of which

switches to throw under different failure modes and make assumptions of

flight time left for example. How about a warning and a count down display

that tells the time left to fly and updates as the pilot changes the

equipment powered on. No action is required if the time remaining is long

enough.



Your insistence of performing your own testing is fine but you are

discarding months of investigation as well as hundreds of hours of testing

and analysis. On the other hand it will save me a lot of time producing a

machine readable copy etc.



A lot of people blindly used your OVP crowbar until it was used with Vans

aircraft and had many reported failures. As far as I know there was never

and failure analysis to prove the true reason for the failures. My own

testing found fault at least two faults with the OVP design but they only

caused false tripping and the real reason appeared to be the use of the

contactor and perhaps rebuilt alternators with possible second rate (read

lower cost) regulators that could not stand up to the resulting load dump

voltage peaks. In any event the OVP design was not properly desinged in the

first place likely due to the test first and skip the analysis under

transient conditions.



It is true I had intended to produce an engineering document VS a

technicians experimental results



I have far too much to do, so its easy to simply bow out. Further I will not

comment on your results as I have better things to do. There is no need to

try to discuss your approach as your mind is seemingly always made up ahead

of time.



You win and I think the group looses. Jet Pilot tried with a lot of real

research and was not listened to either.



We have very very different backgrounds and approaches to design. I had

hoped we could work together but that is not to be. I simply do not have the

time, nor can I stand the frustration of writing one paragraph and getting a

response of several pages of comments which are mostly, to me, not to the

point.



Best wishes



Paul



---

nuckolls.bob(at)cox.net
Guest

Posted: Sun Jul 13, 2008 8:50 am Post subject: Nippondenso alternator question

To: aeroelectric-list(at)matronics.com

Subject: Re: Nippondenso alternator question

At 10:59 PM 7/12/2008 -0700, you wrote:

Well (very sadly but it did seem too good to be true and I am not surprised)

I had hoped for mutual cooperation but I guess you want to do it all your

self. Good timing as I was just finishing the first part of the planned

discussion.

   WHOA! There was no intent on my part to exert any

   form of control over how you responded to this

   new initiative. If you have information to share

   on any topic and in any form, I'm sure it will

   be welcomed by many including myself . . .

Be my guest, I had thought you had changed. Clearly you want to frive the

discussion VS get the benefit of my extensive work.

   Absolutely! However, I just finish an archiological dig

   through records and drives looking for work I did on a

   project at Beech some years back. The $time$ expended looking

   COULD have been well spent looking . . . but in this case,

   BETTER spent repeating the work which I am going to have

   to do anyway. I was only attempting to perhaps relieve you

   of some efforts trying to resurrect past work.

Random comments as its not worth my time to put them in ordered sequence. I

have made some suggestions about how and what to test to avoid missing

information that is not gathered just using your sketched circuit.

You are incorrect about my approach and intent and about my past analysis

and testing which is in my opinion adequate to determine the problem and I

have "crafted" a proven solution. In my opinion there is ZERO need for more

testing other for self aggrandizement.

   Wrong. The repeatable experiment is the CORE of good science.

   No how much testing your or I do, there is always risk of

   error, variability in process or materials, and variability

   in interpretation of results. Finally, there are individuals

   in our society that will stand up, point a finger and accuse

   the tester of having some hidden agenda. There is no stronger

   validation of anyone's work than to say, "Here's what I did,

   here's what happened, here's the significance of the data.

   Oh, by the way, Mr. X in Arizona and Ms. Y in Georgia did

   similar if not identical work and our respective conclusions

   support each other." Besides, I need that equipment and test

   set-up for other activities.

I find this sad as you have not seen

any real results of my testing nor the scope of it. Reading your suggested

approach I find little to agree with so there is no point in my being a part

of your long promised study.

   Paul . . . I don't know what I can write that

   encourages you not to respond to what I do in the

   worst possible light. You have not published one

   White Paper, not one schematic, not one explanation

   of features that helps me or anyone else understand

   diddly-squat about what you're proposing.

Further most of your below comments about my position are totally incorrect

assumptions which is not surprising as you have never spent the time to find

out what my approach is; the amount of analysis, investigation nor testing

setup and results.

   But Paul, you have not shared even the smallest part of what

   you've accomplished. I've reviewed our past exchanges and

   the majority of your efforts were directed at tearing down

   what I had been doing successfully for decades. The only

   data you cited came from manufacturer's data sheets.

I will not tolerate testing as anything other as proof of

pre testing design analysis. I also simply will not design using assumptions

or unofficial verbal assurances from one manufacturer its safe to exceed the

specifications as that is simply a high risk approach no engineer will do.

   If you're talking about crow-barring breakers, exactly WHAT

   limit was being violated? I cited the Mil Std under which all

   those breakers were certified that requires they function as

   advertised when subjected to fault currents of over 1000 amps.

   Many times the values cited in guaranteed performance curves. Curves you

   chose to interpret as limits.

My results are identical design solution for all reasonable alternator but

clearly its not reasonable to allow any alternator to be covered and that

position indicates to me a lack of modern alternator designs etc. Further

you seem fixated on maintaining several design flexiblities and pilot

control that I feel is not only not required but potentially dangerous.

   ??? Now I'm really lost. Are you suggesting that alternators

   can and should be used for aircraft in the manner we've accepted

   for cars? No control whatsoever, no ov protection, no ability

   to manage loads and power generation in multiple alternator

   systems? Is it your suggestion that the design and operation

   protocols common to 99.999% of all aircraft flying can be

   summarily dispensed with?

Also your sketch does not reproduce the real world load dump conditions what

with fixed load and relay contact bounce in the real circuit.

   The sketch depicts only the energy sources and sinks and the

   organization needed to explore the characteristics of an alternator.

   No more. Exploration of contactor performance in the task of

   energy control is a separate experiment.

  Finally it

appears you intend to have a constant string of load dumps which is very

likely to destroy the internal to the regulator load dump protection

components. Each single load dump needs time for the protection circuits to

cool down.

   The "string" for T(off) can be ANYTHING out to infinity. This is a general

   arrangement I used 30 years ago to fine tune the dynamics of

   voltage regulator designs.  Obviously, getting the energy signature

   from a particular combination of L(fixed)+L(switched) can be done

   with very few events. The schematic was intended to describe setup,

   not process details.

   But your statement raises a new question. Where and what are the

   components of "load dump protection" that might be expected to

   sink the overshoot energy? Is this some new feature of an alternator

   for which we are not familiar? What are these energy-sinking devices

   that need resting between events to cool off?

Hopefully you will end up with far more evaluation, studying, and testing

than what you listed below as its not adequate nor has it addressed ALL the

problems I have addressed.

   Never suggested it was. It's a beginning that goes to satisfaction

   of my own curiosity and the sketch was offered as a means for

   revealing those thoughts to you . . . nothing more.

You really should test all the brands of

alternators you intend to approve of and in the several different types and

amps in each style. There are differences to consider. For example different

regulator transient response as well as the winding charactericts which will

determine the load dump information.

    Yup . . . not a simple task and it won't happen quickly.

    It can happen quicker if folks interested in doing such things

    share their work, deduce where variables cited dilute the

    value of comparisons.

    Obviously, we'll never test every brand/configuration of

    alternator available . . . but there are statistical

    sampling techniques that improve the accuracy on upper

    and lower bounds that you adopt for designing a new

    product or system.

Further you should take note of the fact just how much (or more important,

how little) is replaced in rebuilt alternators as if you know what is

replaced you would never recommend a rebuilt alternator (rebuilt is a

misnomer minimal repair is what actually happens).Junk yard is not a source

for ANY aircraft as who knows how close to failure the parts are.

    Really? If the system is truly failure tolerant, why

    would we dissuade anyone from using a salvage yard take-off?

    Who knows, maybe he can find a good deal for a device of

    a Mercedes or something. The goal of failure tolerant design

    is to take reliability concerns for safety out of the decision.

  In any

event testing alone, with out first doing an analysis and manufacturers

detailed data is NEVER sufficient. Both Myself and Jet Pilot found getting

more detailed information was not easy and getting past the sales staff if

difficult at best. However a lot of useful information was passed on and

poo-pooed on this groups list.

    Forgive me. What information beyond hearsay? I have seen

    no documents the manufacturing community offered here. Have

    I missed something? Paul, it's precisely these kinds of

    words that raise concerns for your own "hidden agenda". You

    appear to totally dismiss failure tolerance and absolute

    control as noble design goals. As one who has made a living

    in this environment for nearly 40 years, I'm perplexed by this.

    If these are NOT noble goals, then what goals would you suggest

    replaces them? I've not seen one white paper, not one schematic,

    not one array of test data and interpretation of its significance . . .

    Yup, so in lieu of good data from the source, we gather

    what we can in the field and then utilize those products

    ways that do not compromise safety.

Also be sure to test with a full load current and zero fixed load. Note my

selected 50 amp rated alternator is specified to put out 70 amps at 13V and

more amps at lower voltages so a full output failure results in a much

higher current than your suggested testing which based on my testing is not

nearly worst case!

   Yes . . . that's a subsequent test investigation that looks at

   runaway conditions where the alternator is force to max-out. Or

   if severly overloaded, one might expect greater-than-nameplate

   output current. Name plates are often but should not be LIMITS

   to performance but guanranteed (like those breaker curves?). There

   are explainable conditions under which larger (and smaller) values

   can be expected.

  Another comment about getting the real data first. My NEW

alternator came with a computer printout of the actual alternator during

final test prior to shipment. Note the full amp output is a lot higher than

past comments have been clearly assumed on this list in the past.

   I have assumed nothing . . . and I don't think others here on

   the List have assumed anything either.

. . . .40% higher

is not small in my opinion and under load dump conditions the load being

dumped is much higher energy as well as the peak voltage.

    Your opinion may be well based . . . so? This means we design

    load dump mitigation for some head-room over name-plate-value.

    That's all part of the ball game.

My testing was

based on a real duplication of a typical aircraft wiring including wire

gauge and lengths as well as flight batteries. It started with your OVP and

contactor with the diode on the contactor coil. Very different than what

your sketch shows. Also very long alternator failure point to final

contactor opening requiring voltage clamping during that time of a lot more

energy than what has been assumed in one of your tests from years ago.

   Paul, I was only trying to explain my strongest curiosities for

   the moment that focused on alternator/regulator performance that

   was in no way influenced by methodology for control or OV protection.

   I was hoping that you might have data that went to those questions.

   The sketch illustrated a tool for getting just that data. I WAS hoping

   to focus on one item at a time starting with alternator/regulator then

   control philosophies/techniques and finally over-voltage protection.

But then we have a large and fundamental difference on how to design any

electrical (including aircraft) systems. My approach is to discard many of

the proven pilot opportunities to mess up that have been a reason for past

crashes and leap into the 21st century. Building on the past and not address

the fundamental cause of most accidents is not progress in my opinion. The

more pilot required actions greatly increases the pilots lack or incorrect

action. Today there is no need to do things manually in most cases. Every

manual control available to the pilot 's another opportunity to make a

mistake that can lead to a crash.

   What percentage of crashes have root causes in electrical system

   failures?  What scenarios (FMEA) can you imagine that the complexities

   of any of the Z-Figures present extra-ordinary operational problems

   to the pilot? A light comes on, two switches are repositioned, DONE.

   Your words suggest a marketing philosophy based on a climate of

   fear . . . one of the most powerful behavior modification tools

   available to Madison Avenue (or government). Please assuage my

   concerns. IF a tool supporting your endeavors is to scare the socks

   off (and dollars out?) of the ignorant consumer, then your purpose

   and actions here are unwelcome. I'd rather we share good science.

Today we have Integrated Solid state

switches/circuit breakers. Schottky diodes are not really needed much less

silicon bridges which have no use in aircraft. Yes Solid state switching is

easy to make with full bi-directional isolation and ON resistance less that

of mechanical relays etc switching (as low as 0.002 ohms ON resistance). The

pilot needs to be notified of any CB failure not by finding out by failure

of the component to work for example.

   CB failure? I have worked ONE, count 'em, ONE CB failure issue in

   decades. That had to do with a design flaw in the product. Recall when

   we discussed the consequences of not having the spring-insulator shown

   in:

   http://aeroelectric.com/Pictures/Breakers/W31_1.jpg

   Circuit breakers/fuses are just not high on my list of performance concerns.

   Paul, you seem to be working on another plane of

   existence. A plane that is shared by many of my customers in the

   VLJ business. I'm seeing trends toward a LOT of bells and whistles

   driven by software and the latest in electro-whizzies. I design

   my products to integrate with those systems  . . . it's my job

   and I get paid well for it. But we're working with RV's and

   Kitfoxes. There are very few Lancairs or Glasairs interested in

   what the 'Connection has to offer. Those folks have so much invested

   in their projects that most simply farm their electrical system

   out to whoever offers the most attractive combination of glass and price 

. . .

   architecture and understanding their airplane is WAAAyyyy down

   on the list of concerns.

   Dave Saylor, are you reading this? How many of your Lancair

   customers give a rat's patootie about components of their airplane's

   electrical system work? What percentage would welcome offloading

   understanding and responsibility to the operation of some electronics

   behind the touch-screen?

The aircraft instruments have migrated from steam gauges to flat panels yet

we still find the old contactor relay// switch approach of 1950 etc and that

ignores the modern components available today that are far more reliable and

more pilot friendly.

   Excellent marketing hype. Please quantify "reliability" as it relates to

   safety or cost of ownership in a failure tolerant system. In particular,

   tie this to return on investment in an airplane that on average is

   flown 50 hours a year and seldom ventures into IMC and spends very

   time flying in the dark.

   It would be interesting to survey the OBAM aircraft marketplace and

   see how often the guy uses/needs all those electro-whizzies on

   the panel. I have 850 or so logged hours. I've punched perhaps

   a dozen cloud layers. Except for punching layers, all of my flying

   from J-3 to A-36 could have been handily accomplished with the

   electrical system shut down - using hand-helds and flashlight

   from my flight bag.

   I'll suggest that for the majority of readers on this List

   the electrical system in their project will offer no greater

   criticality than I have experienced over the last 27 years.

Its a fact that pilot error is the major cause of accidents. Its pilot error

if you run out of fuel, deplete the battery based on an assumption of

battery condition and electrical load etc etc. The requirement to throw a

switch in an emergency is bad design if there is a reasonable solution that

eliminates the mechanical pilot action and its done automatically. Its sad

that there is no truly modern system available at a reasonable price on the

market today that automates the system and provides the pilot with useful

real time electrical system conditions. My designs have been peer reviewed

by my (multiple) peers and all have stated its both more reliable and a

great improvement to current 1950's parts and today's arrangements and

approaches. You have long promoted fly the airplane and trouble shoot back

on the ground which is not what your design requirement to turn on and off

the alternator in flight and a simple voltage check is enough for preflight.

Personal situation has delayed getting my system on the market.

   Okay, Paul's agenda identified? I have a customer who asked for some

   advice some years ago about designing a glass-panel, does-everything-

   but-wash-dishes, power management system for light aircraft. He

   threw in a programmable check list to boot. The thing markets for

   over $5,000.

   Paul, I'm writing and designing for folks who choose NOT to

   worry and have FUN building, maintaining and flying an airplane.

   You appear focused on "reliability" and preventing Joe Cool

   pilot from loosing his cool when presented with an electrical

   system conundrum. I prefer to offer solutions where the electrical

   system components are easily acquired, easily understood by the user,

   and TOTAL cost is probably under $2,000. Further, Joe Cool is

   qualified to operate his behaving or mis-behaving system in confidence.

The E-bus is a good example where there is a design requirement to have a

group of avionics disabled during part of the flight and then guess about

how much battery life is left.

   This statement demonstrates that you've NOT read and understood

   the design goals for the e-bus and the admonition that the most

   reliable electrical system flies on a battery of KNOWN capacity.

  . . . A simple additional electrical instrument I

have designed allows the pilot to simply see the real flight time left and

change the load and have the flight time left update. It also determines the

true battery life dynamically. If I am IFR I may need a different set of

avionics than what is on the E bus for example depending on the actual

flight conditions. Or what if the battery power left at any point is less

that what was predicted or measured months ago?.  I know of several off

field crashes due to the battery being depleted well before the expected

time. Another bad design to assume something in particular when it ns not

required to assume. Fuel tank gauges system when the only accurate

requirement is full and empty has been replaced with fuel flow measurement

and totalized as seen in modern automobiles. No reason the battery cannot be

treated the same way, sure its a little more complex but not hard to do with

reasonable accuracy.

There are many ways to make flying safer than having a check list of which

switches to throw under different failure modes and make assumptions of

flight time left for example. How about a warning and a count down display

that tells the time left to fly and updates as the pilot changes the

equipment powered on. No action is required if the time remaining is long

enough.

    Do you have ANY idea what it takes to get such a product

    onto a TC aircraft? There are valid (if not overworked)

    concerns about the accuracy, reliability and effects on

    pilot mind-set when we put highly automated devices into

    the flight management loop. I'm not suggesting that your

    product is any less valuable if you do NOT jump all the

    regulatory hoops but I am suggesting that when you replace

    UNDERSTANDING and COMPETENT operation with an electro-whizzy,

    the potential for unintended consequences are there. Further,

    when we design and sell such devices, we're in essence taking

    on responsibility for operation of that portion of the aircraft.

    I don't mention this from any perspective of assumed liability,

    only from the perspective of Joe Cool pilot who is now even

    more ignorant of his system and more dependent upon his suppliers

    to manage it. Yes, modern electronics lets us do many interesting

    and sometimes amazing things. We'll have to leave it up to

    our customers to decide what dollars are better spent on

    the panel as opposed to fuel and tires.

    I prefer to preach the doctrine of low parts count, low

    cost of ownership, simple-operations backed up by UNDERSTANDING

    of how the system works. I don't believe that products and

    ideas from a 787 trickle down well into an RV.

Your insistence of performing your own testing is fine but you are

discarding months of investigation as well as hundreds of hours of testing

and analysis. On the other hand it will save me a lot of time producing a

machine readable copy etc.

    I am discarding nothing. It was my hope that I SUPPORT

    what you've accomplished and that things you're doing would

    SUPPORT what I'm doing. That appears not to be part of your

    professional modus operandi.

A lot of people blindly used your OVP crowbar until it was used with Vans

aircraft and had many reported failures.

    And not one user of the crowbar OVP system contacted me

    for his/her money back. Not one user came forward even

    when offered a $50 bonus on top of money back if they

    would help me understand the circumstances under which

    their problems occurred.

   As far as I know there was never

and failure analysis to prove the true reason for the failures.

    . . . but my requests for data from folks who were ostensibly

    in communication with "victims" produced no feedback from

    the field.

  My own

testing found fault at least two faults with the OVP design but they only

caused false tripping and the real reason appeared to be the use of the

contactor and perhaps rebuilt alternators with possible second rate (read

lower cost) regulators that could not stand up to the resulting load dump

voltage peaks. In any event the OVP design was not properly designed in the

first place likely due to the test first and skip the analysis under

transient conditions.

It is true I had intended to produce an engineering document VS a

technicians experimental results.

    Excellent! There is nothing anyone has said that argues with

    that. I produced and published volumes of data and analysis

    that argued with your assertions with no responses other than

    to aspersions cast upon my skills and integrity as a designer.

    To date (including my most recent, narrow request for data

    that would define alternator/regulator overshoot performance)

    I don't recall that you've answered a single direct question.

I have far too much to do, so its easy to simply bow out. Further I will not

comment on your results as I have better things to do. There is no need to

try to discuss your approach as your mind is seemingly always made up ahead

of time.

You win and I think the group looses. Jet Pilot tried with a lot of real

research and was not listened to either.

   Other than a lot of tense words in e-mails, he produced no documents

   worthy of a teacher who has practical assemblage of simple-ideas to share.

   I have a standing offer to ANYONE . . . George, Eric, yourself . . .

   anyone to publish any credible work. If you'd like your work-product

   published and indexed on aeroelectric.com, you need only produce it.

We have very very different backgrounds and approaches to design. I had

hoped we could work together but that is not to be. I simply do not have the

time, nor can I stand the frustration of writing one paragraph and getting a

response of several pages of comments which are mostly, to me, not to the

point.

    Absolutely agree. You don't embrace failure tolerance . . . else

    your tools for scaring the potential consumer are crippled. You

    don't embrace teaching your customers how components of their

    system work toward the goal of competent assemblage and

    operation by the user. Those are the points I write and design

    to.

    Paul, it's apparent to me now that nothing has changed in

    either your goals, confrontational mind-set, and inability/

    unwillingness to discuss simple-ideas as they relate to

    servicing our respective constituents with practical designs.

    I'll suggest that your design philosophy and products are

    better suited to pilots who have evolved in the "padded

    cockpit" environment and like to "drive" high-dollar,

    high-performance airplanes. Your offerings might find more

    favorable reception on a Lancair List. If you really believe

    this group has lost, then start your own group. There are about

    1,500 folks on this List who are potential consumers of your

    philosophical and physical work product. If you can entice them

    away from this group, then more power to you sir. If you have

    a better way, then sell it. The marketplace is our ultimate judge

    of success.  I wish you well.

    Bob  . . .

jbr79r(at)yahoo.com
Guest

Posted: Sun Jul 13, 2008 12:08 pm Post subject: Nippondenso alternator question

Hi Bob

I have been trying to follow this thread with little luck, mainly because I got in late and I don't have time for it.  But, that said I want to say there are a lot of Glasairs other than my own that swear by your info and are flying your systems.  My Glll has the dual bat dual alternator system and has run perfectly for 4 yrs.  Others I know, the same.  Keep up the good work

Jim Robinson

Glll  N79R



--- On Sun, 7/13/08, Robert L. Nuckolls, III <nuckolls.bob(at)cox.net> wrote:

From: Robert L. Nuckolls, III <nuckolls.bob(at)cox.net>

Subject: Re: Nippondenso alternator question

To: aeroelectric-list(at)matronics.com

Date: Sunday, July 13, 2008, 10:47 AM




<nuckolls.bob(at)cox.net>



To: aeroelectric-list(at)matronics.com

Subject: Re: Nippondenso alternator question



At 10:59 PM 7/12/2008 -0700, you wrote:




<info(at)mtfind.com>



Well (very sadly but it did seem too good to be true and I am not surprised)

I had hoped for mutual cooperation but I guess you want to do it all your

self. Good timing as I was just finishing the first part of the planned

discussion.



   WHOA! There was no intent on my part to exert any

   form of control over how you responded to this

   new initiative. If you have information to share

   on any topic and in any form, I'm sure it will

   be welcomed by many including myself . . .



Be my guest, I had thought you had changed. Clearly you want to frive the

discussion VS get the benefit of my extensive work.



   Absolutely! However, I just finish an archiological dig

   through records and drives looking for work I did on a

   project at Beech some years back. The $time$ expended looking

   COULD have been well spent looking . . . but in this case,

   BETTER spent repeating the work which I am going to have

   to do anyway. I was only attempting to perhaps relieve you

   of some efforts trying to resurrect past work.



Random comments as its not worth my time to put them in ordered sequence. I

have made some suggestions about how and what to test to avoid missing

information that is not gathered just using your sketched circuit.



You are incorrect about my approach and intent and about my past analysis

and testing which is in my opinion adequate to determine the problem and I

have "crafted" a proven solution. In my opinion there is ZERO need

for more

testing other for self aggrandizement.



   Wrong. The repeatable experiment is the CORE of good science.

   No how much testing your or I do, there is always risk of

   error, variability in process or materials, and variability

   in interpretation of results. Finally, there are individuals

   in our society that will stand up, point a finger and accuse

   the tester of having some hidden agenda. There is no stronger

   validation of anyone's work than to say, "Here's what I did,

   here's what happened, here's the significance of the data.

   Oh, by the way, Mr. X in Arizona and Ms. Y in Georgia did

   similar if not identical work and our respective conclusions

   support each other." Besides, I need that equipment and test

   set-up for other activities.



I find this sad as you have not seen

any real results of my testing nor the scope of it. Reading your suggested

approach I find little to agree with so there is no point in my being a part

of your long promised study.



   Paul . . . I don't know what I can write that

   encourages you not to respond to what I do in the

   worst possible light. You have not published one

   White Paper, not one schematic, not one explanation

   of features that helps me or anyone else understand

   diddly-squat about what you're proposing.



Further most of your below comments about my position are totally incorrect

assumptions which is not surprising as you have never spent the time to find

out what my approach is; the amount of analysis, investigation nor testing

setup and results.



   But Paul, you have not shared even the smallest part of what

   you've accomplished. I've reviewed our past exchanges and

   the majority of your efforts were directed at tearing down

   what I had been doing successfully for decades. The only

   data you cited came from manufacturer's data sheets.

I will not tolerate testing as anything other as proof of

pre testing design analysis. I also simply will not design using assumptions

or unofficial verbal assurances from one manufacturer its safe to exceed the

specifications as that is simply a high risk approach no engineer will do.



   If you're talking about crow-barring breakers, exactly WHAT

   limit was being violated? I cited the Mil Std under which all

   those breakers were certified that requires they function as

   advertised when subjected to fault currents of over 1000 amps.

   Many times the values cited in guaranteed performance curves. Curves you

   chose to interpret as limits.

My results are identical design solution for all reasonable alternator but

clearly its not reasonable to allow any alternator to be covered and that

position indicates to me a lack of modern alternator designs etc. Further

you seem fixated on maintaining several design flexiblities and pilot

control that I feel is not only not required but potentially dangerous.



   ??? Now I'm really lost. Are you suggesting that alternators

   can and should be used for aircraft in the manner we've accepted

   for cars? No control whatsoever, no ov protection, no ability

   to manage loads and power generation in multiple alternator

   systems? Is it your suggestion that the design and operation

   protocols common to 99.999% of all aircraft flying can be

   summarily dispensed with?



Also your sketch does not reproduce the real world load dump conditions what

with fixed load and relay contact bounce in the real circuit.



   The sketch depicts only the energy sources and sinks and the

   organization needed to explore the characteristics of an alternator.

   No more. Exploration of contactor performance in the task of

   energy control is a separate experiment.

  Finally it

appears you intend to have a constant string of load dumps which is very

likely to destroy the internal to the regulator load dump protection

components. Each single load dump needs time for the protection circuits to

cool down.



   The "string" for T(off) can be ANYTHING out to infinity. This is a

general

   arrangement I used 30 years ago to fine tune the dynamics of

   voltage regulator designs.  Obviously, getting the energy signature

   from a particular combination of L(fixed)+L(switched) can be done

   with very few events. The schematic was intended to describe setup,

   not process details.



   But your statement raises a new question. Where and what are the

   components of "load dump protection" that might be expected to

   sink the overshoot energy? Is this some new feature of an alternator

   for which we are not familiar? What are these energy-sinking devices

   that need resting between events to cool off?



Hopefully you will end up with far more evaluation, studying, and testing

than what you listed below as its not adequate nor has it addressed ALL the

problems I have addressed.



   Never suggested it was. It's a beginning that goes to satisfaction

   of my own curiosity and the sketch was offered as a means for

   revealing those thoughts to you . . . nothing more.



You really should test all the brands of

alternators you intend to approve of and in the several different types and

amps in each style. There are differences to consider. For example different

regulator transient response as well as the winding charactericts which will

determine the load dump information.



    Yup . . . not a simple task and it won't happen quickly.

    It can happen quicker if folks interested in doing such things

    share their work, deduce where variables cited dilute the

    value of comparisons.



    Obviously, we'll never test every brand/configuration of

    alternator available . . . but there are statistical

    sampling techniques that improve the accuracy on upper

    and lower bounds that you adopt for designing a new

    product or system.

Further you should take note of the fact just how much (or more important,

how little) is replaced in rebuilt alternators as if you know what is

replaced you would never recommend a rebuilt alternator (rebuilt is a

misnomer minimal repair is what actually happens).Junk yard is not a source

for ANY aircraft as who knows how close to failure the parts are.



    Really? If the system is truly failure tolerant, why

    would we dissuade anyone from using a salvage yard take-off?

    Who knows, maybe he can find a good deal for a device of

    a Mercedes or something. The goal of failure tolerant design

    is to take reliability concerns for safety out of the decision.

  In any

event testing alone, with out first doing an analysis and manufacturers

detailed data is NEVER sufficient. Both Myself and Jet Pilot found getting

more detailed information was not easy and getting past the sales staff if

difficult at best. However a lot of useful information was passed on and

poo-pooed on this groups list.



    Forgive me. What information beyond hearsay? I have seen

    no documents the manufacturing community offered here. Have

    I missed something? Paul, it's precisely these kinds of

    words that raise concerns for your own "hidden agenda". You

    appear to totally dismiss failure tolerance and absolute

    control as noble design goals. As one who has made a living

    in this environment for nearly 40 years, I'm perplexed by this.

    If these are NOT noble goals, then what goals would you suggest

    replaces them? I've not seen one white paper, not one schematic,

    not one array of test data and interpretation of its significance . . .



    Yup, so in lieu of good data from the source, we gather

    what we can in the field and then utilize those products

    ways that do not compromise safety.



Also be sure to test with a full load current and zero fixed load. Note my

selected 50 amp rated alternator is specified to put out 70 amps at 13V and

more amps at lower voltages so a full output failure results in a much

higher current than your suggested testing which based on my testing is not

nearly worst case!



   Yes . . . that's a subsequent test investigation that looks at

   runaway conditions where the alternator is force to max-out. Or

   if severly overloaded, one might expect greater-than-nameplate

   output current. Name plates are often but should not be LIMITS

   to performance but guanranteed (like those breaker curves?). There

   are explainable conditions under which larger (and smaller) values

   can be expected.



  Another comment about getting the real data first. My NEW

alternator came with a computer printout of the actual alternator during

final test prior to shipment. Note the full amp output is a lot higher than

past comments have been clearly assumed on this list in the past.



   I have assumed nothing . . . and I don't think others here on

   the List have assumed anything either.

. . . .40% higher

is not small in my opinion and under load dump conditions the load being

dumped is much higher energy as well as the peak voltage.



    Your opinion may be well based . . . so? This means we design

    load dump mitigation for some head-room over name-plate-value.

    That's all part of the ball game.



My testing was

based on a real duplication of a typical aircraft wiring including wire

gauge and lengths as well as flight batteries. It started with your OVP and

contactor with the diode on the contactor coil. Very different than what

your sketch shows. Also very long alternator failure point to final

contactor opening requiring voltage clamping during that time of a lot more

energy than what has been assumed in one of your tests from years ago.



   Paul, I was only trying to explain my strongest curiosities for

   the moment that focused on alternator/regulator performance that

   was in no way influenced by methodology for control or OV protection.

   I was hoping that you might have data that went to those questions.

   The sketch illustrated a tool for getting just that data. I WAS hoping

   to focus on one item at a time starting with alternator/regulator then

   control philosophies/techniques and finally over-voltage protection.

But then we have a large and fundamental difference on how to design any

electrical (including aircraft) systems. My approach is to discard many of

the proven pilot opportunities to mess up that have been a reason for past

crashes and leap into the 21st century. Building on the past and not address

the fundamental cause of most accidents is not progress in my opinion. The

more pilot required actions greatly increases the pilots lack or incorrect

action. Today there is no need to do things manually in most cases. Every

manual control available to the pilot 's another opportunity to make a

mistake that can lead to a crash.



   What percentage of crashes have root causes in electrical system

   failures?  What scenarios (FMEA) can you imagine that the complexities

   of any of the Z-Figures present extra-ordinary operational problems

   to the pilot? A light comes on, two switches are repositioned, DONE.



   Your words suggest a marketing philosophy based on a climate of

   fear . . . one of the most powerful behavior modification tools

   available to Madison Avenue (or government). Please assuage my

   concerns. IF a tool supporting your endeavors is to scare the socks

   off (and dollars out?) of the ignorant consumer, then your purpose

   and actions here are unwelcome. I'd rather we share good science.



Today we have Integrated Solid state

switches/circuit breakers. Schottky diodes are not really needed much less

silicon bridges which have no use in aircraft. Yes Solid state switching is

easy to make with full bi-directional isolation and ON resistance less that

of mechanical relays etc switching (as low as 0.002 ohms ON resistance). The

pilot needs to be notified of any CB failure not by finding out by failure

of the component to work for example.



   CB failure? I have worked ONE, count 'em, ONE CB failure issue in

   decades. That had to do with a design flaw in the product. Recall when

   we discussed the consequences of not having the spring-insulator shown

   in:

   http://aeroelectric.com/Pictures/Breakers/W31_1.jpg



   Circuit breakers/fuses are just not high on my list of performance concerns.



   Paul, you seem to be working on another plane of

   existence. A plane that is shared by many of my customers in the

   VLJ business. I'm seeing trends toward a LOT of bells and whistles

   driven by software and the latest in electro-whizzies. I design

   my products to integrate with those systems  . . . it's my job

   and I get paid well for it. But we're working with RV's and

   Kitfoxes. There are very few Lancairs or Glasairs interested in

   what the 'Connection has to offer. Those folks have so much invested

   in their projects that most simply farm their electrical system

   out to whoever offers the most attractive combination of glass and price 

. . .

   architecture and understanding their airplane is WAAAyyyy down

   on the list of concerns.



   Dave Saylor, are you reading this? How many of your Lancair

   customers give a rat's patootie about components of their airplane's

   electrical system work? What percentage would welcome offloading

   understanding and responsibility to the operation of some electronics

   behind the touch-screen?



The aircraft instruments have migrated from steam gauges to flat panels yet

we still find the old contactor relay// switch approach of 1950 etc and that

ignores the modern components available today that are far more reliable and

more pilot friendly.



   Excellent marketing hype. Please quantify "reliability" as it

relates to

   safety or cost of ownership in a failure tolerant system. In particular,

   tie this to return on investment in an airplane that on average is

   flown 50 hours a year and seldom ventures into IMC and spends very

   time flying in the dark.



   It would be interesting to survey the OBAM aircraft marketplace and

   see how often the guy uses/needs all those electro-whizzies on

   the panel. I have 850 or so logged hours. I've punched perhaps

   a dozen cloud layers. Except for punching layers, all of my flying

   from J-3 to A-36 could have been handily accomplished with the

   electrical system shut down - using hand-helds and flashlight

   from my flight bag.



   I'll suggest that for the majority of readers on this List

   the electrical system in their project will offer no greater

   criticality than I have experienced over the last 27 years.



Its a fact that pilot error is the major cause of accidents. Its pilot error

if you run out of fuel, deplete the battery based on an assumption of

battery condition and electrical load etc etc. The requirement to throw a

switch in an emergency is bad design if there is a reasonable solution that

eliminates the mechanical pilot action and its done automatically. Its sad

that there is no truly modern system available at a reasonable price on the

market today that automates the system and provides the pilot with useful

real time electrical system conditions. My designs have been peer reviewed

by my (multiple) peers and all have stated its both more reliable and a

great improvement to current 1950's parts and today's arrangements and

approaches. You have long promoted fly the airplane and trouble shoot back

on the ground which is not what your design requirement to turn on and off

the alternator in flight and a simple voltage check is enough for preflight

info(at)mtfind.com
Guest

Posted: Sun Jul 13, 2008 12:25 pm Post subject: Nippondenso alternator question

----Bob: If you knew my background you would understand how wrong you are 

about

my design approach as well as nearly all your comments in this and many

other responses.



My resume includes personal congratulations from the President of the USA

for outstanding scientific excellence, Another is the Presidents award for

outstanding engineering performance at Lockheed. Also there is the multiple

management positions typically manager of the command and control systems

for spacecraft including the Space Telescope.



I have published OBAM designs and design details on several other groups, my

web site, and three national mags. I guess there is a world outside of

aeroelectric.



But this post is breaking my comment not to post again.



I do congratulant your efforts in supporting the group and best wishes.



Paul



- Original Message ----- 

From: "Robert L. Nuckolls, III" <nuckolls.bob(at)cox.net>

To: <aeroelectric-list(at)matronics.com>

Sent: Sunday, July 13, 2008 9:47 AM

Subject: Re: Nippondenso alternator question

 	  Quote: 	
		   

 <nuckolls.bob(at)cox.net>



 To: aeroelectric-list(at)matronics.com

 Subject: Re: Nippondenso alternator question

mrspudandcompany(at)veriz
Guest

Posted: Sun Jul 13, 2008 1:10 pm Post subject: Nippondenso alternator question

Thank you Paul, for going silent!!

Your negative contribution to this forum has taken a lot of time and has

accomplished nothing.  Since you have only tried to tear down Bob's work,

with NO positive contributions. Trying to promote your agenda by trashing

someone else does not work.

Bob, as opposed to Paul, has published many documents to assist the OBAM

community.  There are a variety of different approaches to suit the needs of

most builders.  I have asked questions on several occasions and got a good

accurate professional reply.  In my opinion, the KISS approach with

attention to failure tolerance is the best method for the average builder.

I must commend Bob for the volumes of useful info, free for the taking.

Thanks Bob, and keep up the good work.



Roger

henador_titzoff(at)yahoo.
Guest

Posted: Sun Jul 13, 2008 1:42 pm Post subject: Nippondenso alternator question

Here's what's really strange about Paul's reply.  I've worked in the aerospace field for decades.  I've never known engineers to receive USA Presidential awards unless they were way up at the top and extremely good politicians, totally away from true engineering.  Usually these guys are so far removed from the lab and from where the real action is that they do not know what's going on. Instead, they are at meeting after meeting determinng budgets and how to kill programs, who to promote, who to lay off, taking credit for what people far below have done, etc.  So Paul and whatever your last name is, if you truly have received awards from the USA president, congratulations, you are a great politician.

 Henador Titzoff



---

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