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PM ALTERNATOR- REGULATOR CHOICE

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Peter H

Joined: 20 Mar 2007
Posts: 197

Posted: Sun Apr 22, 2007 10:39 pm Post subject: PM ALTERNATOR- REGULATOR CHOICE

Ken apologies I should have read the Z files first. I have a condenser

connected that way as in Z16. I think I need a different regulator that does

not need excitation from the battery. Bob Nucholls refers to the generic

Ford type regulator, do you know if this is OK for the PM alternator

application?

Peter



--

klehman(at)albedo.net
Guest

Posted: Mon Apr 23, 2007 4:56 am Post subject: PM ALTERNATOR- REGULATOR CHOICE

Peter



I'm not sure why you want a regulator that will start up without a 

battery? It sounds like you do have a battery present. Do you know for 

sure that your regulator will not start without a battery present?



No the Ford regulators will not work with a PM alternator. THey are for 

wound field alternators. Wound field alternators have a field connection 

and circuit breaker that supples current to the field winding. No such 

thing with a PM alternator as the field magnetism is provided by 

Permanent Magnets.



If you intend to use the B&C over voltage module with a PM alternator 

you do need a disconnect relay for the module so the module can 

disconnect the alternator. I use a $3. automotive relay to break an AC 

line from the alternator to the regulator/rectifier.  A diode or 

transorb is incapable of protecting your system from a runaway regulator 

so you need the relay if that is a concern.  Arguably a transorb might 

provide some protection from a momentary spike but we have no real 

evidence to support the existance of such momentary spikes.



Don't get overly concerned about your momentary16 DC volt measurement. 

 Your bad connection could explain everything.  I am pretty confident 

that it was not caused by a misbehaving regulator. I use over voltage 

protection because I run electronic fuel injection and ignition and it 

is not difficult or expensive to add. Some guys use it because they have 

expensive avionics or just because they want to. Some guys don't feel 

the need for it.  The AC volatage will normally be well above 14 volts 

at all times so that is normal.



Ken



Peter Harris wrote:



 	  Quote: 	
		  



Ken apologies I should have read the Z files first. I have a condenser

connected that way as in Z16. I think I need a different regulator that does

not need excitation from the battery. Bob Nucholls refers to the generic

Ford type regulator, do you know if this is OK for the PM alternator

application?

Peter

nuckollsr(at)cox.net
Guest

Posted: Mon Apr 23, 2007 7:31 am Post subject: PM ALTERNATOR- REGULATOR CHOICE

At 08:52 AM 4/23/2007 -0400, you wrote:



 	  Quote: 	
		  



Peter



I'm not sure why you want a regulator that will start up without a 

battery? It sounds like you do have a battery present. Do you know for 

sure that your regulator will not start without a battery present?


	


   Why would one NOT want an alternator that will run

   without a battery. Generators did this from day-one

   and we had to give that feature up when generators got

   replaced by alternators in the 60's.



   Alternators on the Bonanza and Barons have self excited

   for decades and the company touts this as a desirable

   feature. A few months ago we did an exercise to figure

   out how to make an SD-8 come up without assistance from

   a battery.



   This is generally considered a good thing to do and it

   can be done.



   Bob . . .



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

        ( IF one aspires to be "world class",  )

        ( what ever you do must be exercised   )

        ( EVERY day . . .                      )

        (                  R. L. Nuckolls III  )

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

nuckollsr(at)cox.net
Guest

Posted: Mon Apr 23, 2007 7:33 am Post subject: PM ALTERNATOR- REGULATOR CHOICE

At 04:35 PM 4/23/2007 +1000, you wrote:



 	  Quote: 	
		  

<peterjfharris(at)bigpond.com>



Ken apologies I should have read the Z files first. I have a condenser

connected that way as in Z16. I think I need a different regulator that does

not need excitation from the battery. Bob Nucholls refers to the generic

Ford type regulator, do you know if this is OK for the PM alternator

application?


	


   Read the archives and check out Z-25. This pot was stirred

   several months ago.



   Bob . . .

Peter H

Joined: 20 Mar 2007
Posts: 197

Posted: Mon Apr 23, 2007 1:52 pm Post subject: PM ALTERNATOR- REGULATOR CHOICE

Thanks Ken.

I am interested in the possibility of using the alternator as a dual source

for power supply as shown in page Z11 (if I read it correctly) . Basically

two diodes back to back , alternator feed one side, battery feed the other

side and dual source power out from the centre tap. I am preparing to

install EFI in a Jabiru J3300. I will need to study how to load the

alternator when the battery is off line. I have ordered the OVM crowbar and

now sourced an alternator relay, but also need to find the right regulator

for the job. The Jab regulator will not work if the battery is disconnected.

The question about running the PM alternator with battery off line is

covered on page Z 10 note 20 which warns that some regulators will not start

without battery connected.

Still learning and thanks for the insight.

Peter



--

Gilles.Thesee(at)ac-greno
Guest

Posted: Mon Apr 23, 2007 2:03 pm Post subject: PM ALTERNATOR- REGULATOR CHOICE

Peter Harris a écrit :

 	  Quote: 	
		    but also need to find the right regulator

 for the job. The Jab regulator will not work if the battery is disconnected.

 The question about running the PM alternator with battery off line is

 covered on page Z 10 note 20 which warns that some regulators will not start

 without battery connected.


	


Peter,

Have you considered the Schicke GR6 ?

http://www.schicke-electronic.de/dgr3tech.htm



Same as the GR4 I installed some years ago, but with better heat 

rejection capability.

We bench tested it, and it starts to life even with no voltage applied 

to the sense wire. I did not test it with no load at all. There was 

always a battery or capacitor to load it.



Regards,

Gilles

http://contrails.free.fr

Peter H

Joined: 20 Mar 2007
Posts: 197

Posted: Mon Apr 23, 2007 2:35 pm Post subject: Re: PM ALTERNATOR- REGULATOR CHOICE

Thanks Bob I have now a better understanding of Z25, and Gilles. I am a bit handicapped for the Schicke as I am based here in Queensland OZ and do not speak German but I will keep it in mind and it is good to get a first hand recommendation.

I will be pleased to find another alternative recommendation.

Thanks I appreciate the good advice on this list 

Peter

klehman(at)albedo.net
Guest

Posted: Tue Apr 24, 2007 4:45 am Post subject: PM ALTERNATOR- REGULATOR CHOICE

To his credit, Peter has been asking lots of questions and I was trying 

to understand whether it was worth his effort to change parts and insure 

self excitation.  For my Z-14 system, it doesn't matter to me whether 

either alternator will self excite. If I don't like how the engine is 

running, my procedure is to just switch to the second EFI system, which 

runs on the other battery and alternator.

Self excitation is fine but I would encourage a bit of testing before 

counting on continued operation without a battery. Especially with a 

regulator that was not designed to perform without a battery.  Now that 

Peter's has described what he is trying to do, I agree that self 

excitation or a second battery is essential for him.  However self 

excitation might not help much if someone inadvertantly stalled the 

alternator and had a geared prop that promptly stopped turning.  Self 

excitation might not be as comforting if Peter's EFI Jabiru doesn't 

windmill fast enough to restart his engine.  For example he might want 

to insure that with his system it is not possible to inadvertantly (out 

of habit) turn on something like a landing light and stall the 

alternator... His "dual" power source should probably be strictly for 

feeding the engine.  My PM alternator doesn't put out much current at 

idle rpm.

Ken

Robert L. Nuckolls, III wrote:

 	  Quote: 	

 <nuckollsr(at)cox.net>

 At 08:52 AM 4/23/2007 -0400, you wrote:

> 

>

> Peter

>

> I'm not sure why you want a regulator that will start up without a 

> battery? It sounds like you do have a battery present. Do you know 

> for sure that your regulator will not start without a battery present?

   Why would one NOT want an alternator that will run

   without a battery. Generators did this from day-one

   and we had to give that feature up when generators got

   replaced by alternators in the 60's.

   Alternators on the Bonanza and Barons have self excited

   for decades and the company touts this as a desirable

   feature. A few months ago we did an exercise to figure

   out how to make an SD-8 come up without assistance from

   a battery.

   This is generally considered a good thing to do and it

   can be done.

   Bob . . .

Peter H

Joined: 20 Mar 2007
Posts: 197

Posted: Wed Apr 25, 2007 2:09 am Post subject: PM ALTERNATOR- REGULATOR CHOICE

Ken,

I will need about 4A to run the EFI. Ignition is dual by one magneto and one

electronic ignition module . It will be OK by me if I can cover the EFI

only. But how much current would stall the alternator and stop the engine?

Peter



--

klehman(at)albedo.net
Guest

Posted: Wed Apr 25, 2007 5:57 pm Post subject: PM ALTERNATOR- REGULATOR CHOICE

Peter



Stall is perhaps not the best term for me to have used.  I would think 

that the best plan then would be that your alternator should be able to 

supply at least 4 amps at idle in case you pull power back to idle. What 

you want to avoid is any possible combination of rpm and electrical load 

that could pull the voltage below what your EFI system needs to keep 

running. Many automotive systems will run down to about 8 volts or they 

would not be able to start the car with a weak battery. They typically 

lengthen the injection pulse at low voltage to compensate for more 

sluggish injector operation. I don't know how many amps the Jabiru 

alternator will put out at idle but I'd guess that your plan will work 

if the alternator is only powering the EFI. Definitely worth a try I 

think! If it doesn't work you can always try adding a small battery.



There have been some interesting alternatives used over the years such 

as gravity fed fuel to a port or nozzle that can meter enough fuel in to 

keep you airborne. One then used the throttle as a mixture control. 

Similarly there have been cases where someone made it to the airport 

with the priming pump after their carburetor quit supplying fuel.  I've 

also heard that such schemes often caused more troubles than they saved  ;(



Ken



Peter Harris wrote:



 	  Quote: 	
		  



Ken,

I will need about 4A to run the EFI. Ignition is dual by one magneto and one

electronic ignition module . It will be OK by me if I can cover the EFI

only. But how much current would stall the alternator and stop the engine?

Peter

Peter H

Joined: 20 Mar 2007
Posts: 197

Posted: Wed Apr 25, 2007 7:47 pm Post subject: PM ALTERNATOR- REGULATOR CHOICE

Thanks Ken. I was thinking of using a carb as the throttle body but have

since inspected the Aerocarb and found it unsuitable. There are other

possibilities, I am still cooking but most result in a compromise of some

kind.

Thanks for the input.

Peter



--

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