Voltage issue

[mtfleming]

Sometimes when I start my mep002 the voltage drops to about 200v under load. When this happens the voltage adjustment will not raise voltage. If I keep trying and the voltage stays at 240v it works fine. Are their brushes that might need checking?

 

[Triple Jim]

No, there aren't any brushes in that generator. You could start by checking the 6 diodes on the diode board that's in the cabinet under the output lugs. They rectify output from CVT1 to make the exciter field current, and if one has an intermittent problem, or if there's a bad connection there, the current could drop.

There are some other things to check if that board is OK, but that's a simple place to start.

 

[Guyfang]

Be more a little more clear. Does the voltage drop on the gen set meter, and you verified that by measuring at the output terminals? Or it drops on the meter and you haven't confirmed it by measuring at the output terminals. You can't always go by the set meter.

 

[Chainbreaker]

Also, with unit OFF/Shut down, exercise the Voltage Reconnection Switch a few times to insure it maintains a good connection on its contacts just in case it has oxidized the contacts and is not getting a reliable connection. If it doesn't turn its probably stuck in place. While you are in the load distribution box cabinet checking out the things Triple Jim suggested it would not hurt to spray that switch with a suitable electrical contact cleaner and work it back-and-forth and then reset to 120/240. Some people have had to loosen the internal switch mechanism nuts just enough to get switch to move and spray in contact cleaner then re-tighten and exercise.