MEP003A High Voltage

[m38inmaine]

Gen set worked in the AM, started in the PM and voltage went high, 160v AC but still rock solid 60Hz. It's been running my off grid home for several weeks while my primary set is being repaired. Swapped out the voltage regulator in another set and that tests out fine. Any suggestions what to check next?, browsing the TM now.

Thanks

T2 ohms out good

 

[Chainbreaker]

This thread describes some good troubleshooting tips when encountering unstable voltage (high):

http://www.steelsoldiers.com/showthread.php?141590-MEP-003A-Unstable-Voltage

 

[jamawieb]

High voltage is caused by the voltage regulator 98% of the time. If it's not that, then its T2 transformer or the CVT1 transformer. Since you'll tested T2, try testing CVT1 in the distribution box. You will need to take all the leads off and then check it according to the TM. If it is CVT1 they are getting harder to find, I had one go out this year and it took 2 months to find one for sale.

 

[m38inmaine]

I looked over the CVT1 and I don't see where the terminals are marked so I can test it. Is CVT1 the T1 transformer in the top cubicle or is that the one in the bottom with the wire looped through it?

 

[jamawieb]

CVT1 is in the distribution box (lower box) and has the main wires looped through it. There are actually 2 transformers there, CVT and CVT1; CVT1 is in the back. Yes it is hard to see the markings while its in the box, I'll see if I have my old CVT1 to give you the location of the wires. Recently someone had a problem with no voltage and they posted a picture of the markings of CVT1.
T2 is in the control cubicle where the gauges are located. When testing the T2 and CVT1, you have to disconnect the wires to get an accurate ohm reading.

 

[m38inmaine]

I did disconnect T2 in the top cubicle to get my readings and they were spot on according to the TM. I did notice that the top portion of CVT1 has several cracks in the plastic. The CVT, outer is not cracked, it doesn't look like much fun to get that thing out.

I found the thread with the CVT1 layout, I will ohm it out tonight and report back, thanks.

 

[cuad4u]

Just about every CT I have seen in 002A and 003A generators has cracked plastic coating and many have the plastic mounting "feet" broken off. Cracked plastic does not seem to matter in their operation.