View single post by Mark Olson
 Posted: Tue Sep 15th, 2020 07:44 pm
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Mark Olson

 

Joined: Thu Nov 22nd, 2018
Location: Baton Rouge, Louisiana USA
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Yes, there is 'Potential" for the fan body to be 'hot' (pun intended). Usually the switch blade is line voltage, and only insulated by the knob itself, that leaves the frame neutral, Ideally, the fan should be insulated so that reverse polarity does not cause the fan frame to become hot. There may be missing insulating washers on the choke or switch, or there could be voltage leakage from the choke to frame, or the stator to frame. A conventional VOM does not supply a high potential to check for such leakage, although modern meters are very sensitive in the several Megohms range. A "megger" or Hi-pot (high potential tester) gives way more insight as to the condition of the windings, because they test at about 500 volts.