I tried using the water the other day, and - no water. I went into the kitchen and no water there. it was the weekend, so I immediately thought of $$$$$$ for a weekend service call and a new well pump. I checked the circuit breaker and it wasn't tripped - which gave me a little hope that it wasn't going to be a major repair bill. I went to the well pump pressure tank and surprise. The plastic shroud over the well pump pressure switch had
a hole melted through the top. I could see assorted black stuff through the hole, like a major current surge had fried things.
I took off the plastic cover and the switch looked like it had run under ten times normal current. The wire end was vaporized, the tail of the crimp connector was gone, and the head of the crimp was melted and fused to the attaching screw, which had welded itself to the screw holder. I couldn't get the screw to budge.
I installed a new pressure switch/relay and things have been normal since. No problems.
Pictures attached. I suspect that the crimp wasn't crimped enough and the connector had overheated due to a higher than usual resistance. The pump causes a lot of vibration as it pumps the water through the piping to the pressure tank, so the crimp probably loosened up even more and eventually got high enough resistance that it blew.
For $20 and an hour of my time, we had water again!