Testing an Electric Blanket
Paul Hovnanian P.E. wrote:
Nelson wrote:
Not really electronics, I know, but I'm hoping some one can throw me a
pointer. I'd like to test for both safety and shorts/opens/too much
resistance. The only thing I could find on the web is safety testing
by electric utilities.
Any DIY help would be appreciated.
Put a GFCI receptacle in where you plug this blanket in.
I'm not sure a GFI would do any good. All electric blankets I have ever
seen are two-wire devices, and there is no ground in or around the
blanket. No ground = no ground fault = happy GFI.
I did see a blanket fail once, out in the middle of the blanket (i.e.,
not near the connector). I THINK the failure mechanism was a heating
wire that had been flexed enough that it was ready to break - but hadn't
quite broken yet. The fracturing wire got thinner, which increased the
resistance at that point, which overheated the wire at the incipient
break, which caused a hot spot that was hot enough to scorch the blanket
material (the material does not support flame, by the way).
This was NOT a short circuit. The heating wires are well separated, and
anchored in place quite well.
Bill
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