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Dead PlanePower alternator- internal bits and wiring?

My Plane Power also failed this weekend after 830 hours of service. Happened away from base but for some reason I have packed my spare alternator for the trip. I did not have the time to do fault finding yet.

Slight thread drift - I have always started and then switched on the field switch in order for the alternator to start charging. Is there any evidence or data out there that might suggest that one should have the field switch on before starting?
Hi Jan, I saw a video of the Plane Power/Hartzell guys from Oshkosh this year, and the PP expert said something to the effect of "I don't know why you would want to have the alternator on during the starting event." I changed my process to turn on the alternator after engine start based on this statement.

When shutting down, I leave the alternator on until after the engine stops.

I believe it was this video:

https://www.youtube.com/watch?v=T8owuXdKeRc
 
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Hi Jan, I saw a video of the Plane Power/Hartzell guys from Oshkosh this year, and the PP expert said something to the effect of "I don't know why you would want to have the alternator on during the starting event." I changed my process to turn on the alternator after engine start based on this statement.

When shutting down, I leave the alternator on until after the engine stops.

Thanks Mickey, exactly what I have been doing for years now.
 
Have you found the alternator field switch in your car?
Right!?
Why on earth would PP think that switching the alt on after start is a reasonable operational/design limitation.
Looking for the head slap emoji....


and to think that I've been designing to pass DO-160 voltage spike and power input testing all these years for nothing. I could just that require Joe Pilot push in the breaker when the electrical system is stable! :D
 
Right!?
Why on earth would PP think that switching the alt on after start is a reasonable operational/design limitation.
Looking for the head slap emoji....


and to think that I've been designing to pass DO-160 voltage spike and power input testing all these years for nothing. I could just that require Joe Pilot push in the breaker when the electrical system is stable! :D

I understand what you and DanH are saying - and I know that Bob Nuckolls says the same thing. Two things - 1) modern cars are doing lots of things with their millions of relays, so it's not clear if they are turning off the alternator during cranking or not. I have no idea. ; 2) the guy that I need to call when my PP alternator dies said "turn it off when cranking" (effectively) and I hope he knows more about his product than I do, so I feel more comfortable following his advice until I get more data that shows he's wrong.

I also have no idea what an alternator does when trying to get the V in V=IR back up when it's so low - is this something that's bad for the alternator?
 
Yes, but your car has 3-4 times the cranking capacity of my 540. I leave it off to save the 5 amps and several HP load.

Larry

The current draw on the field wire is essentially 0 when the alternator isn't spinning.

The HP load is caused >after< the starter disengages and the alternator is trying to charge the battery (or the battery is trying to suck every joule out of the alternator -- perspective I suppose...)
 
The current draw on the field wire is essentially 0 when the alternator isn't spinning.

Have you verified this? My tests indicate that when the engine isn't running and battery voltage is in the 12-12.5V range, both my primary and back up B&C alternators/voltage regulators are drawing full field current (~5A apiece) from the battery.
 
Have you verified this? My tests indicate that when the engine isn't running and battery voltage is in the 12-12.5V range, both my primary and back up B&C alternators/voltage regulators are drawing full field current (~5A apiece) from the battery.

Interesting -- I had checked this on an internally regulated PP AL12-60 a while back. As the field current is controlled by the regulator it could be a behavior of the regulator -OR- I could have had a bad set of brushes when I looked at this...
 
Although a field draw may reduce cranking power by some wee bit, the point isn't relevant to regulator or alternator durability.

Mickey, I've attached an illustration from a classic reference, Bosch's Automotive Electrics/Electronics . Sure, some recent designs may control the alternator field through a central ECM, and not supply field excitation during cranking...but we went roughly 50 years with what you see in these diagrams.
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Internally regulated alternators have access to the alternator's phase signal terminal (one of the stator wires), they can detect when the alternator starts spinning and only apply field current when it's spinning.
They also have load response control, soft start, thermal compensation (lower setpoint at higher temps) and a bunch of other features. There's a reason the regulator is inside the alternator. Not sure how much of these features are retained in PlanePower's regulator though.

So cars do have a field switch, it's just managed by the internal voltage regulator which is really an alternator controller.

B & C's field is always energized. It's a simple & reliable system using old school components from the 90s (someone posted photos of the circuit board on here a while ago), no software, but also not very smart.

FWIW, Balmar makes a really smart multistage alternator controller for boat alternators. Would be great if someone came out with something similar for aircraft.
https://balmar.net/balmar-technology/multi-stage-regulation/

The current technology is hard on both batteries and alternators. It undercharges batteries, and overloads alternators when using lithium batteries.

Lenny
 
The current draw on the field wire is essentially 0 when the alternator isn't spinning.

The HP load is caused >after< the starter disengages and the alternator is trying to charge the battery (or the battery is trying to suck every joule out of the alternator -- perspective I suppose...)

First, the alternator is spinning while cranking the engine and second, when the voltage drops to 10 while cranking, the regulator is throwing the full current on the field, trying to bring it back up to 14.

Larry
 
Internally regulated alternators have access to the alternator's phase signal terminal (one of the stator wires), they can detect when the alternator starts spinning and only apply field current when it's spinning.
They also have load response control, soft start, thermal compensation (lower setpoint at higher temps) and a bunch of other features. There's a reason the regulator is inside the alternator. Not sure how much of these features are retained in PlanePower's regulator though.

So cars do have a field switch, it's just managed by the internal voltage regulator which is really an alternator controller.

B & C's field is always energized. It's a simple & reliable system using old school components from the 90s (someone posted photos of the circuit board on here a while ago), no software, but also not very smart.

FWIW, Balmar makes a really smart multistage alternator controller for boat alternators. Would be great if someone came out with something similar for aircraft.
https://balmar.net/balmar-technology/multi-stage-regulation/

The current technology is hard on both batteries and alternators. It undercharges batteries, and overloads alternators when using lithium batteries.

Lenny

This was my understanding. However, in my case, I have an external regulator with no connection to the stator. Spinning or not, it is drawing a alot of amps on the field as soon as the regulator gets its source voltage. Further, once the alternator starts spinning during cranking, that full field current is creating a load on the starter somewhere in the neighborhood of 3-5 HP.

I agree that this extra load is not significant in many cases, but it is for me in the winter, where I need every CCA available to me.

Larry
 
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Just one more point, then I'm done -- fly your airplane how you want.

Watts = Volts * Amps
Horsepower = Watts/746 (1HP = 746W)

Ergo, when Alt Field is energized @ 13.2Vdc it will "burn" 66 Watts (13.2 * 5 = 66)

66 Watts => .0885075 Horsepower.

Not 3 - 5 HP.
 
Internally regulated alternators have access to the alternator's phase signal terminal (one of the stator wires), they can detect when the alternator starts spinning and only apply field current when it's spinning.
They also have load response control, soft start, thermal compensation (lower setpoint at higher temps) and a bunch of other features. There's a reason the regulator is inside the alternator. Not sure how much of these features are retained in PlanePower's regulator though.

So cars do have a field switch, it's just managed by the internal voltage regulator which is really an alternator controller.

B & C's field is always energized. It's a simple & reliable system using old school components from the 90s (someone posted photos of the circuit board on here a while ago), no software, but also not very smart.


Lenny, at the fundamental level, the B&C would be an external regulator version of the Bosch diagrams?
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I think so, but i'm wrong a lot. Now too, check this out:

I was curious and hooked up my spare PP alternator's B lead and field wire to a power supply at 12.8V (fully charged AGM battery voltage). Resulted in 4.3A draw. Not good.
Last PP alternator I checked wasn't drawing anything with a stopped rotor. Maybe they changed their regulator to a "more reliable" one. :)

Lenny

Lenny, the B&C would be an external regulator version of the Bosch diagrams?
 

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I think so, but i'm wrong a lot. Now too, check this out:

I was curious and hooked up my spare PP alternator's B lead and field wire to a power supply at 12.8V (fully charged AGM battery voltage). Resulted in 4.3A draw. Not good.
Last PP alternator I checked wasn't drawing anything with a stopped rotor. Maybe they changed their regulator to a "more reliable" one. :)

Lenny

I'll recheck mine this weekend -- really confused about what I was seeing earlier.
 
I can confirm that all the PPs I have seen will draw current when the Field terminal gets power. Roughly 4A. In fact my first test when someone has charging problems is to switch on the Master and the Field and test for magnetism on the pulley. If your Field switch and wiring to the alternator is good, a small spanner or anything else magnetic will hang on the pulley. Switch off and it will fall to the ground.
 
Ok, I rechecked mine in-situ -- I used a simple compass in the vicinity of the alternator (bottom right of propeller spinner/cowl interface) to determine the presence/absence of a magnetic field --

Alt Field Switch (Off) - Compass was lazy in movement and pointed North
Alt Field Switch (On) - Compass swung hard right +60° from prior direction

Q.E.D. -- Current is flowing in the Alternator Field Rotor when energized and Not rotating. PP Alternator model 99-1012.

So I will retract my earlier assertion that there was no current flowing in the PP alternator (It must have been the bad brush assy). However, the math demonstrated in post #65 still stands...
 
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Hey I just wanted to make a comment that this thread saved my bacon and a lot of money this week. I was AOG at an unfamiliar airport with alternator failure.

Net is that my Plane Power alternator gave up (but it was heavily stressed by a battery issue) and I used this thread to replace the 11-1043 Brush/Regulator assembly. was easy to do and this thread was Super Helpful!!

Tim
 
Hey I just wanted to make a comment that this thread saved my bacon and a lot of money this week. I was AOG at an unfamiliar airport with alternator failure.

Net is that my Plane Power alternator gave up (but it was heavily stressed by a battery issue) and I used this thread to replace the 11-1043 Brush/Regulator assembly. was easy to do and this thread was Super Helpful!!

Tim

Tim, I sent you a PM re: your AOG experience.

By any chance do you have a blast tube pointed at the back-side of the alternator?
 
Field Current

Data point from my early model Plane Power 60 amp alternator,

Resting field current is 2.21 amps @ 12.6 volts, nearly 28 watts and it does get warm to the touch after 20 minutes or so.
 
Net is that my Plane Power alternator gave up (but it was heavily stressed by a battery issue) and I used this thread to replace the 11-1043 Brush/Regulator assembly. was easy to do and this thread was Super Helpful!!

Tim

Tim, I understand that you had your alternator checked or repaired at a local shop. What shop did you use and do you have contact info?

-Marc
 
Replacement Stator P/N for 60A PP Alternator

Maybe this will help somebody out...

Turns out after 1225 hours I had some broken stator wires, common problem. That may or may not have led to a failed rectifier replaced this spring. If anybody is ever looking for a replacement stator for their Plane Power 60 Amp AL12-EI60B alternator, the part number to find is:

Denso 27-8209, 27-8200/340-52005

The stator is 36 slots, 100 mm OD, 77 mm ID, 25-26 mm long (laminated steel core). With the copper windings the length is 54 mm. ~15AWG wire (0.058 in dia).

Online prices range from $22- $50. Takes about an hour to swap out, a little fiddly but pretty straightforward.

Sources current as of this writing include:

https://www.amazon.com/dp/B07HFGR9PR/ref=cm_sw_r_apan_glt_fabc_1YYT90PTY1SK9T9K6XRJ

https://www.ebay.com/itm/New-Stator...2349624.m46890.l49286&mkrid=711-127632-2357-0

https://www.ebay.com/itm/Electrical...2349624.m46890.l49286&mkrid=711-127632-2357-0

https://issuu.com/arrowheadep/docs/componentscatalog/72

https://www.innovav.top/index.php?main_page=product_info&products_id=736338

I was unable to find the P/N for this stator despite hours of searching the forums, so hope this might help somebody out sometime. Good luck.
Apoligies for the thread revival.

I have this same model of alternator, and the rectifier has died. I cant seem to find a match for it, and PP is not replying to inquiries. Did you find any number for it perhaps while you were researching?
 
Apoligies for the thread revival.

I have this same model of alternator, and the rectifier has died. I cant seem to find a match for it, and PP is not replying to inquiries. Did you find any number for it perhaps while you were researching?
A few years ago I replaced the rectifier in my 60A PP alternator with an INR 724 rectifier. Worked great for a while and then it died too. LifePO4 batteries are working the alternator pretty hard after engine start. This was it but looks like it's no longer available from that vendor.
 
Thanks for everyone who has comment and helped. I've ordered an inr724 from overseas, can't seem to source one in Australia.

PP/Hartzell did reply this morning and advised me to get a 11-1043 from spruce, but from what I can tell this is the brushes/reg NOT the rectifier.

I have asked for clarification and will advise.

Thanks again for you're collective help!
 
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