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Jeff Wisnia
 
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Default How to upgrade outlets and switches

RBM wrote:

The ground fault device and anything plugged into any outlets connected to
the load side of it, will cause the GFCI to trip if any leak of current to
ground occurs, regardless if the outlets are grounded. The GFCI does not
need a ground connected to it to function


Of course, but that's NOT what I asked.

I was talking about (internal fault) leakage to the safety ground lead
(chassis) oF an appliance with a three wire cord and plug. And, that
faulty appliance is plugged into a GFCI outlet which does not have a
ground wire run to it. i.e. an outlet which would require the little
label stuck on it warning that there was no safety ground there.

Take a look at Sam Goldwasser's diagrams and explain please how the GFCI
can sense internal leakage to the safety ground lead of the appliance if
the ground pin hole in the outlet isn't connected to anything.

http://www.codecheck.com/gfci_principal.htm

Jeff




"Jeff Wisnia" wrote in message
...

PipeDown wrote:


Use of a single GFCI or a GFCI breaker does not solve the problem of not
having a ground wire in the first place. If you use a GFCI receptacle
and connect several receptacles downsteam, you will get some GFCI
protection but not from current into ground (the ground tab on those will
still be open). Only at the GFCI receptacle itself do you get virtual
safety ground protection.


I think I understand you. But just to be sure, are you saying that even
without a ground wire connected to it the first GFCI receptacle would trip
if an appliance plugged into it equipped with a three wire cord and plug
developed internal leakage between hot and ground (or on the fancier GFCIs
also between neutral and ground.), but that you don't get that level of
protection on the downstream ones?

I'd assume you wouldn't get that protection on the first receptical either
if there was no ground wire connected to it. I can't see where a leakage
current to ground would flow if there was no ground wire for it to flow
through.

If what you said assumed there WAS a ground wire to connect to the GFCI
receptical then I agree with your statement, but that's prolly not what
the OP has, unless he's lucky and the wall boxes are grounded, perhaps via
the bare ground wire used in some of the old BX cables.

snipped

Jeff



--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"Life is like a sewer -- what you get out of it depends on what you put
into it."