On 12/03/2015 3:08 PM, Don Y wrote:
....

E.g., note that when I unplugged the lamps this morning and re-plugged
them, they didn't trip the breaker. Yet, plugging them "cold" caused
an instant trip. So, modify the experiment -- wait *10* seconds
before re-plugging. Then, 2 minutes.

Ah, now I have new information to assist in formulating a theory
(what, in the circuit, can "account for time"?)

A thermal effect as postulated previously.

....

Agreed. I'll return to my original plan of diagnosis.

....

_IF_ you did still have high quality test gear, I'd tend to agree with
your attempt at more esoteric trouble-shooting. Lacking that, the
likelihood of placing a measurement at the right spot with the facility
to catch the event is approaching zero...

So you might as well eliminate the one common component from the problem
before continuing down all those various ratholes you've previously
enumerated...

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