#### Jim Goodman

##### JEG in Raleigh

The generator has a running amperage capacity of 67 amps, and according to the specifications, a surge capacity of 130 amps (which seems high). Of the 3 high amperage loads (that I really don’t want to have to control manually and can come on automatically), the heat pump has a starting LRA rating of 47 amps and a running load of 11.7 amps. The well pump has a starting LRA rating of 48 amps and a running load of 8 amps, and the water heater uses 19 amps.

Today, when our power went out, I ran to the breaker panel and turned off the breakers for the heat pump, the water heater, and the well pump. With those items turned off, the total electric load that the generator was supplying was 21.3 amps. I wanted to make sure the well pump would run on the generator, so I went to the panel and turned on the well pump breaker. The lights went off and the generator stalled. At that point, the load was 21.3 amps (the stuff running in the house) + the starting locked rotor amps of the well pump of 48 amps = 69.3 amps, which is 3 amps over running capacity of the generator, but well below the supposed 130 amp surge capacity of the generator.

At this point, I flipped the breaker for the well pump off again and after about 15 seconds the generator started up and once again, was supplying power for the 21.3 amps of load that it had been supplying prior to my turning the well pump on.

Next, I flipped off all the breakers in the house….every single one…...so there was zero load on the generator. I once again flipped on the well pump breaker. At this point, the total load on the generator was only the current draw of the well pump at startup, which was 48 amps. The running capacity of the generator is 67 amps, so the well pump should have easily started, but it did not. Again, the generator stalled out. I flipped the well pump breaker off again, and this time, the generator did not start back up. I had to go out to the generator and reset the control panel, which had the error code E1902, “UNDERVOLTAGE OVERLOAD”.

If I were to do it again, I’d get a bigger generator, but this is what I have. It just doesn’t seem right that this 16kw generator will not start that well pump. I see people running well pumps off of portable generators with no problem. The well pump is on a 20 amp breaker in the house, and it never trips the breaker. And I have a Cycle Stop Valve and Cycle Sensor. The readout of the current draw when the well pump is running is 6-8 amps, once it’s running after startup. Hoping to get some opinions about this problem. I'm trying to eliminate possible reasons for this to try to get to the root cause. Do you think the well pump has anything to do with the problem or is it all related to the generator? Thanks.