Well, things were looking too good for awhile to continue I guess. Generator worked beautifully yesterday with a paralleled 120 output and the 120V AVR holding things to within close to a tenth of a volt at different loads.
This afternoon while running, however, I heard a return of the loud hum. Intermittently. I call it a hum instead of a growl, because that's what it sounds like to me. Loud electrical hum.
I did read all of the other threads here that the search brought up under "growl", but those threads talked about unevenly loaded legs in a two leg setup. Mine is paralleled 120V.
While nobody seemed to think it was serious (just irritating), in the other threads, in this case it is. When I hear the hum, a 100 watt incandecent bulb dims, and my Kill-A Watt shows a big droop in voltage. Not sure how much droop because the hum is intermittent, and the meter is a slow sampler, but I saw one momentary display go below 100V.
The AVR doesn't make a differece in whether it happens. Intermittent hum occurs with or without the AVR switch on. And the AVR doesn't seem to be able to maintain the output voltage during the hum.
As I said, the setup is paralleled 120 V output (not 240 two leg). There's a 1500 watt heater and the 100 watt bulb as the load. Roughly a half load on the 6-1 Metro.
I'm thinking it's either an intermittent internal short, or an intermittent open in the genhead wiring somewhere.
I guess an open in one paralleled "leg" could mean the other "leg": is momentarily taking all the load and thus humming like an unbalanced 240v 2 leg -- is that right?
But it seems that when people have this situation with a 240 two leg, it just makes a noise, but doesn't cause a voltage drop, does it?
That's what has me worried.
