MEP 003 fluctuating voltage

[drjconley]

I have a MEP 003 that I replaced the voltage regulator board last weekend. I can adjust the voltage now with the rheostat, but the voltage will not stay steady. The voltage will go up and down approximately 15 volts for a total variation of 30 volts. I tested the output with a voltmeter to make sure it is not the gauge, and the gauge is correct. The engine stays at a steady rpm and I am getting a steady 60 Hertz. I will be working on it next weekend and I am putting together a list of things to check.

Is there an obvious cause to this voltage fluctuation that I should check first?

Thanks,
Jim

 

[Speddmon]

The new voltage regulator probably needs adjusted. The TM explains the test circuit for checking and adjusting the voltage regulator (I'm sure you saw this in your troubleshooting of the other regulator). Because of the age of these units, I'm guessing that the regulator is a used one, it's probably just a matter of "dialing" it in. There are several pots on the regulator to adjust, one of them will fine tune the regulation to stop the "hunting" you are describing.

 

[drjconley]

Thank you again Speddmon if you lived closer I would drive over and buy you a beer. I really do appreciate your help.

I read the TM 5-6115-585-34 and on page 6-8 the directions say to adjust resistor R15.


Does anyone have a picture or a good description as to where resistor R15 is?

Jim

 

[Speddmon]

It should be at the bottom of the board, around the middle somewhere....it's going to be a pot actually, not so much a resistor.....It's circled in the attached copy from the TM -24

I'll just be happy to hear you got it running smoothly once again....maybe someday down the road at a distant rally or something like that we'll settle up on the beer.

 

[drjconley]

I finally got it working. It was the voltage regulator. I have a friend who helps me out and I let him rewire the new regulator. I gave him the schematic that came with the new board and he wired it up. I should have double checked his work. I rechecked it yesterday and after rewireing it, it worked great. I would like to thank Speddmon for all his help and guidance, it is appreciated.

Jim