Got a service call today, contactor #5 (there are a total of 6) humming/buzzing loudly. Traced it to coil. When I tapped it, I got different levels of 'hum', however, at its highest level it was quite annoying.
Anyways, what caused it to hum? Is this common to contactors?
Here are particulars if anybody cares... Square D product. 120V coil, and 3 pole 40amp rated, but only 15A @ 120V max actual load per pole.
Sandro.
