I went to steel soldiers before I came here, and found myself trapped in the Vehicle forum and could not escape. I'll have another try.I think you are in the wrong place. You should go to https://www.steelsoldiers.com. There is an entire section on MEP units. Some participants are experts. For a start, visit Thread: MEP-003A problems. Post and members will tell you what happened,and where to get replacement part.
I was thinking arc of an overload could break a loose connection, and I've found loose connections on the units I own.Are they equally suspect in causing this? The circumstance -- turning on the AC kicked the overload switch --certainly suggests a part got overloaded, not some other demon like mouse-gnawed wiring.
Good points. Found my way around at steel soldiers this morning and carried this thread there. 4 and 5 years ago they helped me choose an 003 and set it up.I was thinking arc of an overload could break a loose connection, and I've found loose connections on the units I own.
On Steelsoldiers forum, go to Auxillary equipment section, as noted above, there is a lot of info, free TMs, and helpful people who work on these all the time.
That will probably be the best guide to this.There are 3 CT transformers in this generator. Only one is used for single phase, the other two are for three phase. Check the resistance of all three and if one is different swap it with one of the others. If all CT transformers read the same then your ammeter is bad.