Basic Question About AC Power Wiring

3 tons wrote:
I’ll venture a guess or two...

Since this malady happens with either generator (with only a slight variation) I’d look elsewhere...

Since the Microwave begins to cycle off and back on, that’s a huge clue that the 120v power supply is intermittent to the RV’s main breaker panel...This also results in a intermittent power supply to the air cond, causing an overheating condition at the compressor’s passive thermal overload switch - thermal switch subsequently auto-resets...

The ATS switch has a gen-start time delay option (for gen warm-up) of about 15 to say 30 sec - this is normal...But if the power supply to the ATS Switch is intermittent, the time delay will re-occur with each power interruption...

Bottom line is that either the ATS is defective or there is a faulty connection somewhere between the power cord and (or at) the ATS...

JMO,

3 tons

Ok, you are understanding the symptoms very well.

Only slight differences are:

1) the gen startup time delay doesn’t happen when the power cycles on and off every second or two on the generator that’s attached to the shore power cable.

2) when this cycling is happening, the air conditioning unit runs like it’s experiencing a brownout. Fan slows, compressor slows. Then I get scared of damage and quickly turn off the air conditioner.

ATS was also my first thought . I opened it, looked through it, but didn’t see the problem. I’ll look much more thoroughly as a first try.

The control for the ATS is electronic, right? Like the circuit board in a refrigerator that can (and does) go bad?

I haven’t fully understood how the ATS works yet. I see a solenoid and a pair of contacts with a spring. I don’t HEAR any of the clicking sound it normally makes when it comes on and starts the power during the cycling. It just rapidly cycles on and off without making a sound.