"Nate Nagel" wrote in message
...
Hi all,

got a real puzzler. Bought and old canister type vacuum off eBay and it
arrived today. Hooked it up, started testing it out, seemed to work fine.
Vacuumed the kitchen and dining room (tile floor) then got to an area rug
in front of the sink. Switched to the power head and it worked OK for a
minute or so and then tripped its built in circuit breaker. I noticed
when it was operating that the light bulb flickered a little bit. Reset
it, tried it again, same thing, but this time I grabbed the (steel) wand
instead of the rubber coated end of the hose and got that unmistakeable
tingle of AC. I whipped out my trusty Fluke and can't seem to find
anything in the wand, hose, etc. where either of the power leads are
shorting to steel; same thing with the body of the vacuum itself. I even
metered between both prongs of the power cord to the vacuum case, still
nothing. I *suspect* that the issue is with the power head, but there
doesn't seem to be anything amiss there that I can identify with a meter -
if nothing else, there's no way for even a short to the case to get to the
wand, as there is no possible electrical connection between the body of
the power head and the wand (the connecting piece is plastic.) The one
thing I did not do was to hook up the power head and operate it and
measure the voltage from the wand to a known ground; I didn't want to
smoke the thing completely and then have the seller tell me that I damaged
it.

I'm inclined to just box the whole thing up and send it back for a refund,
but I'm quite honestly puzzled - can anyone come up with a reasonable
explanation as to how this could happen, given what I saw with my meter
above? This is really perturbing me, usually I can come up with a
reasonable explanation as to why something failed the way it did, but I
don't get this one.

To make matters weirder, the vacuum was plugged into a GFCI protected
outlet and the GFCI didn't trip. Or can one still feel a tingle below the
threshold fault current for a typical GFCI?

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
A possibility is that the tingle was due to static electricity generated by
the air flow, especially if the humidity was low. We had a system at work
that pumped oil thru a vinyl hose and it would give you a pretty good jolt
sometimes from the hose. That is why gasoline hoses are partially
conductive.

Don Young