Hi,
Thought you guys would be able to help me on this.
Why would my 220 volt table saw hum when its plugged in and not running. It is in a newly built shop about 60 feet away from the main house. I noticed this the other day when I went in, so I unplugged it. It was fairly cold (35 degrees) in the unheated building. It runs fine when being used. All the wiring seems to have the right polarity. When I turn on the fluorescent lights they hum also until they warm up , but I know that is normal. I am stumped as to why the saw would hum without even being turned on.
Thanks in advance for your thoughts, Yanni

The hum is normal in cold temps. But make sure everything is grounded!
N9ZAS.

I know very little about Power Distribution, but there might be a phasing issue with your power leads. Could also be a ungrounded motor frame. I'd suggest discussing the issue [which may, in fact, not be a real problem] with your local Power Company technicians and perhaps also your local electric motor rebuilding technician. Don't know about motors, but the power transformers in home entertainment [etc] equipment quite often would hum obnoxiously, until the bolts holding the transformers plates together were tightened up. Some wouldn't quiet down, until the transformer was given a fresh application of shellac/varnish, to 'reglue' the 'vibrating' plates, of which the transformer is made.