Alternator over-voltage and trip... back to Battery Voltage...

Ahh Yes I see where I went terribly wrong, in reading the R1224 install procedure I mis-read this note from the manual

"...Connect the ENABLE terminal to the regulator/field power source (the wire from the cockpit ALTERNATOR FIELD switch which is fed from a 7.5 max amp breaker)...."

I mis-read this to read ENABLE to REG on the alternator...

I can see how badly I screwed up !

That the exciter post on the alt. being labeled REG by InterAv rather than AUX isn't helpful either.
 
Okay, so today I re-wired all the connections with new terminals and new wires.

1. The enable wire has bus voltage that goes on and off with ALT on and off switch in the cockpit.

2. FLD connected directly to field on the alternator unit- flat spade connector.

3. A Jumper is installed between ENABLE and SENSE terminals on the PP regulator.

4. A jumper is also installed between SENSE and AUX of the PP regulator (per the installation manual, Guide M)

All this and STILL NO LUCK

What am I missing ?

Is it possible that I fried the Voltage Regulator and/or the Alternator while I had the wiring wrong and when it showed excessive voltage and current upwards of 40 Amps and then cut off ?

Argghh this has been a battle ...

The fight continues!
 
DUH ...Just re-read Chip's message...

I think THIS is what I am missing ;

"The post labeled "Reg" on the InterAv alternator goes to the "aux" post on the PP regulator" <------------ I have NOT done this... probably explains why nothing is happening ?
 
well - I re wired EVERY SINGLE connection with new terminals and new cables. The enable wire has bus voltage that goes on and off with ALT on and off switch in the cockpit.

FLD connected directly to field on the alternator unit- flat spade connector.

grounds are good

jumper installed between ENABLE and SENSE terminals on the PP regulator.

I can measure bus voltage at enable terminal with master and ALT ON

what am I missing ???

just fired it up and still nothing - no charge and no alternator voltage showing !

the guide M of the R1224 manual says jumper ENABLE and AUX ? But next line it says for REV C and later jumper ENABLE and SENSE .


So I do both ? Or just the one I have - that is jumper between SENSE and ENABLE ?

argghh this has been a battle ...

The fight continues!

A look at the cover of the regulator will tell you what revision it is, but if it's new, it's a C. The one jumper is what you use. Did you check for bus voltage at the alternator output post, maybe that breaker popped during your video adventure? For grins, did you check for 8v or so at the REG post of the alt? Are you certain the internal jumpers in the regulator are set to 12v? If all that checks, what is your field voltage master on engine off? When you run a jumper to your VOM from the field post and start it up, do you get any voltage?

If you have bus voltage at enable and sense, a good connection between the alt field terminal and the regulator field, and a good B+ from the bus at the alternator, that's really all you need for the regulator. All can tell you at this point is to use the troubleshooting checklist and methodically check every single item. If everything checks out, call support.
 
Last edited:
DUH ...Just re-read Chip's message...

I think THIS is what I am missing ;

"The post labeled "Reg" on the InterAv alternator goes to the "aux" post on the PP regulator" <------------ I have NOT done this... probably explains why nothing is happening ?

You can try it, but it's really only needed if you have a low voltage annunciator light. What you do need to check is that there's 8v or so at the REG post at the alternator with the master on, engine off.

Does that Bo have some sort of fuse block in the field wire harness? Have you actually visually traced the harness?
 
Wire it as shown in this drawing and it should work. If I read your comments right I think this last try is close but not quite. Also, as Chip mentioned, check the jumper configuration and break out a volt meter to measure what you’re getting at the various points.

https://planepower.aero/wp-content/...e-Engine-Externally-Regulated-Alternators.pdf

I suspect you’re falling into the trap I wrote about initially - Plane Power’s instructions (which got even worse after Hartzell acquired them) are poor at best and can leave a person quite confused. Their product works great after it is installed but it can take a bit to get there if the installer is unfamiliar.
 
Yes, I traced the enable wire all the way back to the ALT breaker and switch... And no I didn't see a fuse block anywhere, but I did check to see the breaker had NOT tripped.
There was bus voltage at the B+ at the alternator.

The way I have it now... No there is no 8V at the REG terminal with the master and ALT ON...

More confusion...
 
Wire it as shown in this drawing and it should work. If I read your comments right I think this last try is close but not quite. Also, as Chip mentioned, check the jumper configuration and break out a volt meter to measure what you’re getting at the various points.

https://planepower.aero/wp-content/...e-Engine-Externally-Regulated-Alternators.pdf

I suspect you’re falling into the trap I wrote about initially - Plane Power’s instructions (which got even worse after Hartzell acquired them) are poor at best and can leave a person quite confused. Their product works great after it is installed but it can take a bit to get there if the installer is unfamiliar.


Yes - I printed two copies of this and had it right there and the measurements checks according to this flow sheet....
 
Yes, I traced the enable wire all the way back to the ALT breaker and switch... And no I didn't see a fuse block anywhere, but I did check to see the breaker had NOT tripped.
There was bus voltage at the B+ at the alternator.

The way I have it now... No there is no 8V at the REG terminal with the master and ALT ON...

More confusion...

Ok, that's a clue. That sounds like there's no excitation voltage to get the alt started. There's two ways for that to happen, voltage from the regulator, or a resistor between the B+ post and the Reg post. Some installations removed that resistor. Try the aux connection and see what happens.
What was the voltage reading at the field terminal, master on, engine off, both at the alt and at the regulator?
 
Last edited:
Ok, that's a clue. That sounds like there's no excitation voltage to get the alt started. There's two ways for that to happen, voltage from the regulator, or a resistor between the B+ post and the Reg post. Some installations removed that resistor. Try the aux connection and see what happens.

Aha.... I removed the resistor because the new alternator came with a bright blue tag that said to remove it if NOT using a InterAV regulator... when I had it ON earlier... I did see ~7-8 V at the REG terminal, obvioulsy, came there from the B+ after the drop... will put it back and see... I am thinking either this OR the Aux to Reg but not both... correct?
 
For what it’s worth, both of the Cubs I’ve done this swap on have the resistor still intact.
 
Aha.... I removed the resistor because the new alternator came with a bright blue tag that said to remove it if NOT using a InterAV regulator... when I had it ON earlier... I did see ~7-8 V at the REG terminal, obvioulsy, came there from the B+ after the drop... will put it back and see... I am thinking either this OR the Aux to Reg but not both... correct?

I can't answer that for you definitively. Check the voltage at the regulator aux post before you connect it and see what's there. If there's good voltage, 8-12v, then it's probably sufficient to excite the alt. If there's not, reinstall the resistor. My sense is one or both wouldn't make any difference because if the alternator quits it's going to draw down the battery and excitation will be of no consequence anyway. And with the master off, it's all shut down so there's no parasite draw like there is in other applications, but support would answer that better than I can.
 
Just took a quick look at the 1224 manual, and it says no connection is necessary to the aux terminal if a low volt lamp isn't used. So I would presume the resistor is necessary for excitation.
 
The Hartzell rep happened to be in my neck of the woods today, and he was so very kind to drop in at the hangar and did a complete review of the set up. He is also an A&P/IA and has tons of experience on alternators and charging systems (their product lines that he is a tech rep for)....

So.. here is the verdict.

1. The wiring is correct, including the enable wire from the ALT switch via breaker to the regulator. Physically traced and tested.
2. Confirmed all the connections are correct and secure.

BUT....

Didn't pass the sniff test ! Literally ! In my prior voltage and current excursions, yes, you guessed it... managed to deep fry the regulator...once the cover was removed the smell was obvious...

So, getting a replacement this week.

Here is a picture of the Southern Fried Regulator :) I am in Alabama after all !
 

Attachments

  • Fried Regulator .jpg
    Fried Regulator .jpg
    216.6 KB · Views: 28
The Hartzell rep happened to be in my neck of the woods today, and he was so very kind to drop in at the hangar and did a complete review of the set up. He is also an A&P/IA and has tons of experience on alternators and charging systems (their product lines that he is a tech rep for)....

So.. here is the verdict.

1. The wiring is correct, including the enable wire from the ALT switch via breaker to the regulator. Physically traced and tested.
2. Confirmed all the connections are correct and secure.

BUT....

Didn't pass the sniff test ! Literally ! In my prior voltage and current excursions, yes, you guessed it... managed to deep fry the regulator...once the cover was removed the smell was obvious...

So, getting a replacement this week.

Here is a picture of the Southern Fried Regulator :) I am in Alabama after all !

Gotta keep the smoke in!! Let it out? No bueno.
 
The Hartzell rep happened to be in my neck of the woods today, and he was so very kind to drop in at the hangar and did a complete review of the set up. He is also an A&P/IA and has tons of experience on alternators and charging systems (their product lines that he is a tech rep for)....

So.. here is the verdict.

1. The wiring is correct, including the enable wire from the ALT switch via breaker to the regulator. Physically traced and tested.
2. Confirmed all the connections are correct and secure.

BUT....

Didn't pass the sniff test ! Literally ! In my prior voltage and current excursions, yes, you guessed it... managed to deep fry the regulator...once the cover was removed the smell was obvious...

So, getting a replacement this week.

Here is a picture of the Southern Fried Regulator :) I am in Alabama after all !

Ouch. I was afraid that was going to be the case after seeing the video. Without the breaker, it couldn't protect itself. At least the end is in sight, and you'll have a solid system. Did he give you guidance on the aux post?
 
Ouch. I was afraid that was going to be the case after seeing the video. Without the breaker, it couldn't protect itself. At least the end is in sight, and you'll have a solid system. Did he give you guidance on the aux post?

Interestingly, he said, the AUX post isn't necessary, but having the resistor there won't hurt, but isn't essential he said... He was under the impression that the field voltage is sufficient excitation to let the Alternator start making juice once it is turning... We will find out soon enough, he is scheduled to come out and replace it and test it..
 
Interestingly, he said, the AUX post isn't necessary, but having the resistor there won't hurt, but isn't essential he said... He was under the impression that the field voltage is sufficient excitation to let the Alternator start making juice once it is turning... We will find out soon enough, he is scheduled to come out and replace it and test it..

OK, so the with the master on, engine off the regulator senses low alt output and sends full voltage to the field. Makes sense (no pun intended).
 
OK, so the with the master on, engine off the regulator senses low alt output and sends full voltage to the field. Makes sense (no pun intended).

:) Glad it makes sense ... I am still trying to wrap my head around it... but yes, that does explain why the tech was very puzzled when he didn't get the bus voltage on the field post or terminal. That diagnostic is rather confusing because that "flow" showed, IF no bus voltage at FLD, then move to check at ENABLE (Which would be a yes) and then on down, as if it is okay to not have bus voltage at FLD. That is what threw me off totally.

Second - the root cause of the fried regulator - in one of the "iterations", there was an instant when there was full bus voltage applied to the FLD terminal AND ENABLE, albeit from two different sources... THAT caused it to fry... is my speculation. (When, due to frustration, my brain went to INOP mode)
 
FINALLY !

Everything is fixed up good and is working good.

Hartzell rep came back with a replacement regulator, brought another tech with him, spent close to 5 hours, completely re-doing all the wiring with new 16 ga wire, added a new 5 amp breaker, made the connections secure with new terminal connectors and made a modification on the location of the regulator. I had it where the old InterAv was, which was right behind the baffle plates near the engine compartment. He mounted it inside the cabin, behind the firewall, on the original mounting plate that came with the 1959 Bonanza. Secured it with vibration dampened fasteners. Added better ground connections. Tested and ensure it is all working well.

When I asked how can I thank them for this... his answer was " You already did - by buying our products " - now THAT is a great attitude and a fantastic response. I am very impressed with their support.

Also, thanks to Chip, PaulS, and all the others who regularly chimed in and shared very valuable pieces of information. I've learned a bunch during this time. All of this has been extremely helpful. Thank you all very much.
 
Back
Top