[Norm K]

Yesterday, out of the blue and on its own, my irrigation pump turned on. The panel where I typically turn it on (with the various zones) was in the "Off" position. I moved it to the "On" setting, then turned it back off. The pump kept running.

Went up to the main electrical panel and switched the 30 amp double pole breaker off. The water flow stopped. Switched it back on and ... nothing. Moved the zone panel switch back to "On" but still nothing. Walked down to the dock where the sub-panel is located and switched the 20 amp d-pole breaker off, then back on. Walked back up to the house and switched the 30 amp one on again. The pump came on, but with very little pressure.

With my healthy fear of 240 volts firmly in-hand and foremost in mind, I removed the inner panel of the sub-panel and probed around with my multi-meter. I'm getting 120v across the wired terminals and 120V across where the other end of the breaker snaps into place.

Here's what's throwing me: I'm getting 120 volts on of the the wired terminals to the bus bar, but no voltage from the other side to the bus bar. I'm trying to hear a difference in my mind's ear between how the pump sounds now versus how it sounded yesterday (when everything was working properly) but have to admit to being uncertain. It'll spit water of out a couple of the heads nearest the lake, but nothing any higher than that. Will the pump run at half power if half the circuit breaker isn't producing?

Ideas welcome!

_