Charging problem

Electrical issues
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Joined: Mon Jul 16, 2007 4:55 pm

Charging problem


Post by PanBobberDude » Sat Jun 21, 2003 11:17 pm

Description: I have a 12V generator on my Pan. It suddenly stopped charging.

I have a 12V generator on my Pan. It suddenly stopped charging. I need help to find out what's wrong.
The two field coils are in serial between A and F terminal. Resistance between A & F is 5.1 Ohm.
Resistance over commutator (Positive to negative brush) is 2.5 Ohm.
There is about the same resistance between all terminals on the commutator. No connection between commutator and ground.
Brushes are OK.
If I ground terminal F and measure the voltage on terminal A, it only gives 0.5 Volts at about 2000 rpm. If it was OK it should have given more than 12 Volts.
I also tried to connect an old battery to A. F was grounded for maximum charge. The battery voltage went down from about 11 to 2.5 Volts. When running the engine up to about 3000 rpm, the voltage only went up to about 5 Volts.
The Current and Voltage regulator was not in use on these tests.
All screws are tight. What can be wrong? I need to find out if there is something wrong with the field coils or the armature (or something else).


Posts: 51
Joined: Fri Jul 13, 2007 8:47 am

Re: Charging problem


Post by 57Kicker » Sun Jun 22, 2003 5:08 am

You kinda lost me in all the electronic tech terms. By the sounds of it there may be something wrong with the generator for sure.
I was having a chrging problem as well, and I talked to a bro' of mine who has a 55Pan with the same kinda 12volt gen as me and you. He was telling me that sometimes one of the brushes, over time, comes lose (or something like that) and will start to ground out causing the battery to drain and not be recharged. The generator might need to be rebuilt with new brushes...possibly.
I'm only passing on what I was told. I haven't had to do this..yet. My prob was solved by replacing my wiring from the generator to the voltage regulator and the wire from the regulator to the batter+ terminal as well. I found a lose connection with one of the connectors, just like someone here told me i might find. (thankyou kell) I couldn't belive it, It looked like a good connection, seemed sound enough....until I gently tugged it and out it slide with the greatest of ease!
Now I went for a 2 hour night ride with the lights on and the old "skunk" ran like a watch! WOOHOO!

CHEERS!....I owe Kell a beer now

Posts: 404
Joined: Sat Jun 19, 2004 2:58 am

Re: Charging problem


Post by kell » Mon Jun 23, 2003 1:49 am

57Kicker -- who loves ya baby!
PanBobberDude: Here is something that happened to my generator a while back. It wasn't charging, I took it apart and found that one of the brushes was stuck in the slide, so it wasn't touching the armature (right word?). Though if you have gone to all the trouble you have so far with the testing, maybe you have also checked the brushes by now. Just thought I'd mention it.

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