MEP007B Low voltage

[mrichard76]

I recently purchased a MEP007B that was load tested, producing correct voltage etc. Only issue then was the hertz meter was not functioning. Got it back home and now voltage meter also quit working and was only getting 120 volts across legs when measured at the lugs. Tried adjusting throttle to get 60 hertz (measured on multi meter) and was reading 137 volts across lugs, neutral to lugs or ground to lugs 8 volts. No electricity at 120v convenience outlets. Power coming into voltage meter at connections is 137v. Any ideas what's going on here?

 

[Guyfang]

Did you hold the start switch up long enough to let the set self excite?

 

[mrichard76]

Yes sir

 

[Guyfang]

When you hold up the S2, (Start Switch) and let the engine go through its starting phase, do the volts and hertz meters move at all? Do them come up, until you let the S2 go? Or make any movement at all? What voltage do you get at the 120 volt outlets? Do you get any idiot lights, after letting the S2 go, other then LOW VOLTAGE?

 

[mrichard76]

Meters don't move at all, no low vltage light, low oil pressure light comes on but goes away after reset. have 60 psi oil pressure. No voltage at 120v outlets.

 

[Guyfang]

Have you pushed the S9, (Over Speed Switch) reset button?

 

[mrichard76]

Yes we have

 

[Guyfang]

Can you read schematics? If so, You need to check out if the S9 is sending initial excitation to the Main gen. Should be S9-2 function. Pins A&C I think.

 

[mrichard76]

Pins B&C? What kind of voltage should we be looking for?

 

[Guyfang]

No. You want J37. Its the plug that goes to the S9.
These help any?

 

[mrichard76]

Well.... noticed the batteries were weak so we changed them and now we have 208 volts. Not sure if it was bad voltage from the batteries or a bad ground but appears to be making correct voltage now. Hertz meter still not functioning, maybe a bad meter. Anybody have a source for a replacement?

 

[Guyfang]

Go to the A2, (frequency converter) in the control panel. See in the input side has 120 volts on it. Should be the left side of the A2. Then see what you have on the output side. It will be DC .

 

[peapvp]

Well.... noticed the batteries were weak so we changed them and now we have 208 volts. Not sure if it was bad voltage from the batteries or a bad ground but appears to be making correct voltage now. Hertz meter still not functioning, maybe a bad meter. Anybody have a source for a replacement?

This is a 100KW Unit!

This is not exactly the MEP Model you are trying to get your feet wet getting into Military Generators.

A 3KW, 5KW or 10KW can give you already a magnificent firework beyond your wildest imagination for the money you spent on it.

I would strongly suggest that you seek the help of a local expert to get this Unit overlooked and worked on correctly

 

[mrichard76]

We are getting 120v on the AC side and 0 .6v on the DC side

 

[mrichard76]

The frequency meter now jumps briefly while the engine rpms ramps up and jumps again while rpms fall upon shutting the engine down,

 

[Guyfang]

I would say your A2 is bad.