MEP-004A Gen Set not generating any voltage?

[bushton4]

I have a MEP-004A gen set. Pulled it in the shed last nite to warm it up and get it started.

Everything fired up and it was showing correct voltage and frequency at that time. Pulled the set 20 miles home and it was not showing anything on the voltage or frequency gauges. Pulled out the volt meter and checked sure enough no voltage at the lugs.

I converted this rig over to single phase about 8 yrs ago and it has never missed a beat, till last nite. Tried running it with the battle short opened up and still nothing.

When I close the generate circuit the amber light comes on and the gauges move a little bit but then fall back to the resting position.

Also tried plugging in my electric drill to the 110 V outlet and running it backwards with a cordless to excite the field, still nothing. I have lost excitation before on pto gen sets and this simple trick got the field re excited. This time nothing.

Has anyone ran into this scenario?? I dont have a book on it and will look on here as soon as I get this posted to see if there is a TM on here.

 

[Scoobyshep]

When you start it, hold the start switch up, do you see voltage?

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[bushton4]

When you start it, hold the start switch up, do you see voltage?

Sent from my SM-G973U using Tapatalk

N O

 

[robertsears1]

Maybe vibration got something loose on the drive home. Does that unit have a panel in the control area that you can drop down and check behind.? Wiggle every connection you can see if something came loose.

Robert

 

[Scoobyshep]

N O

Check your field wiring. Behind the control panel by the AVR is a terminal block, when in start do you get 24 volt?

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[Guyfang]

I have a MEP-004A gen set. Pulled it in the shed last nite to warm it up and get it started.

Everything fired up and it was showing correct voltage and frequency at that time. Pulled the set 20 miles home and it was not showing anything on the voltage or frequency gauges. Pulled out the volt meter and checked sure enough no voltage at the lugs.

I converted this rig over to single phase about 8 yrs ago and it has never missed a beat, till last nite. Tried running it with the battle short opened up and still nothing.

When I close the generate circuit the amber light comes on and the gauges move a little bit but then fall back to the resting position.

Also tried plugging in my electric drill to the 110 V outlet and running it backwards with a cordless to excite the field, still nothing. I have lost excitation before on pto gen sets and this simple trick got the field re excited. This time nothing. This "trick" will not work with any Mil Standard gen set bigger then a 1.5 or 3 KW gasser. The small movement you see on the volt meter at startup should be excitation voltage. The first thing to check, is TB-16. That's the TB that Scooby is talking about. Have someone measure across the two terminals for DC voltage. There is a troubleshooting procedure in the TM. You should explore that. Also take out the A11, regulator/exciter, better known as the Static Exciter assy. Open it and see if anything is loose, or burned up.

Yes, the TM's are located in the TM forum.

Has anyone ran into this scenario?? I don't have a book on it and will look on here as soon as I get this posted to see if there is a TM on here.

Open to read comments.

 

[bushton4]

ok, so i couldnt find anything out of the ordinary behind the panel. it is all clean, orderly and in good shape. started messing with the start switch, suddenly got voltage and freq on the next start up.

next 3 times nothing.

GRRRR

Thru some trial and error, mainly error, I figured out I was not holding the start toggle up long enough. As soon as the oil pressure comes up I would release the toggle to run.

Holding the toggle for about 3-5 seconds in the start position after the oil pressure comes up and both the voltage and freq. come up to where they are suppose to be. Did not realize this was required upon start up. Happened on it by sheer accident.

Tested this out 6 times in a row and it never failed. Short started it on the 7 time and no voltage or freq.

SO holding the start toggle up for 3-5 seconds after the oil pressure comes up is now SOP.

Thanks for the effort to help guys
Stay warm

 

[Scoobyshep]

My friends 005 does the same thing, have to hold the flash a few seconds longer to get the field going

 

[Guyfang]

ok, so i couldnt find anything out of the ordinary behind the panel. it is all clean, orderly and in good shape. started messing with the start switch, suddenly got voltage and freq on the next start up.

next 3 times nothing.

GRRRR

Thru some trial and error, mainly error, I figured out I was not holding the start toggle up long enough. As soon as the oil pressure comes up I would release the toggle to run.

Holding the toggle for about 3-5 seconds in the start position after the oil pressure comes up and both the voltage and freq. come up to where they are suppose to be. Did not realize this was required upon start up. Happened on it by sheer accident.

Tested this out 6 times in a row and it never failed. Short started it on the 7 time and no voltage or freq.

SO holding the start toggle up for 3-5 seconds after the oil pressure comes up is now SOP.

Thanks for the effort to help guys
Stay warm

If you only knew how many folks have made this mistake. I am one also. Pays to read the -12 TM. ANY, I say again, ANY Mil-Standard gen set has to be held in the start position a TAD longer. If you ever git a gear clash, then you need to check the MPU.

 

[Guyfang]

My friends 005 does the same thing, have to hold the flash a few seconds longer to get the field going

Scooby, it has to do with the S9 switch. The old type were manual switches. The new type are electric, and still have that problem. Go to the -34 TM and check out the internial schematic for the S9-1 function.

 

[Scoobyshep]

Scooby, it has to do with the S9 switch. The old type were manual switches. The new type are electric, and still have that problem. Go to the -34 TM and check out the internial schematic for the S9-1 function.

Ill have to dig into it, It will work, it just takes a few seconds to get to voltage.

 

[Guyfang]

We all consider it "Normal" by now. I would never even think about it anymore. Just hold the S1, (or S2) up till you see the hertz and volt meter come up and hold steady. Then let go.