Thanks Ken,
At 38.2 amps, the sound is a buzz, crackle more than a whine, perhaps at 20 to 30 HZ but not entirely rhythmic, a completely different sound than when battery voltage is still higher than the adjustment pot dictates.
When I turn off AC power to the unit it makes the same buzz click for a about 2 seconds.
Wait, I just did so, when it had nothing attached to the output but the gt power, and it did not make the noise, but then started to and when i looked over it I saw the fan blades slowing down in the same rhythm as the slowing buzzing.
Come to think of it the noise was a bit more rapid with the old fan which is higher rpm.
Perhaps it is the fan itself making the noise when the unit is maxed out at 38 amps.
I'll have to bust out my mechanics stethoscope tonight and put it on the fan hub at 38.2 amps. If it is just the fan, i'll dance a little jig, in private of course. :)
