On Wed, 22 Feb 2006 21:13:39 -0800, "Harold and Susan Vordos"
wrote:


"Wild Bill" wrote in message
roups.com...
snip-----

The actual fault could be something as simple as a pinched, but not
shorted, wire (lowering the voltage breakdown level of the wire's
insulation)

I found just such a problem in a 1/2 horse motor I use for my tool bit
grinder. It ran fine, but showed voltage from the housing to ground.
Grounding the housing eliminated the problem, but when I dismantled the
motor to replace bearings, I found the source a wire that had been crushed
between two members. Insulation was intact, but there was a high resistance
leak. Taped the crushed portion and the problem went away.

Harold



snip

Harold, I had one like that last year, only it was the power wiring to
a 460 V. 15 Hp. motor crushed in the motor junction box cover.
Luckily, the AB Powerflex 700 VFD was smart enough to instantly trip,
so no light show. This was on a new installation.

Pete Keillor