[scsmith]

This was discussed in another thread last week. Plane Power alternator, 400 hrs. indicated voltage at cruise conditions was 14.8 to 15.2 V With added load, like lights, the indicated voltage would drop to 14.4 V.

Bob Turner said it was an indication of some line resistance in the field wire.
I checked the terminal connections at the field switch and at the master switch (which must be on to energize field). Both fine.

I pulled the field connector plug off the back of the alternator and pinched the contact sockets closed a bit, as demonstrated by Dan Horton.

Problem solved. Indicated voltage is 14.4 now, regardless of load.

Thanks guys!

 

[DanH]

Steve, squeezing the contacts didn't last with mine. I'd suggest ordering a new plug, just so you have it on hand. Search the threads, because I recall someone finding them for way less money than Plane Power wants for them.

Oh, and pot the back of the plug with some silicone sealant so the terminals can't wiggle. I think fretting contributes to contact wear/resistance.

 

[scsmith]

Thanks Dan,

I found that old thread. I was reluctant to pot the connector because it precludes replacing it without splicing on more wire. But if I pot it, maybe I won't need to replace it.
So, I'll use the same liquid rubber you did.

Thanks again.