Here;s a situation I came across.
I know any time a metal mounting box is used for a duplex outlet the box should be tied to the ground wire coming in.
What if the metal box/outlet is on the load side of an upstream GFCI?
Maybe codes say it still has to be grounded (?) but from a safety standpoint is it pointless to ground the metal box?
Metal boxes should always be "grounded".
cheers Bob
Hi, Floating metal box is not a good idea. If hot touches the box you can get zapped.
It must be grounded, gfci or not.
As others mentioned, the NEC requires it to be bonded (connected to an EGC). And there is an advantage to this even when the conductors are GFCI protected.
Suppose the hot conductor faults to the box. If the box is bonded, this will immediately create a short circuit and trip the circuit breaker or GFCI. If the box is not bonded, nothing will happen until you come along and complete a circuit with your body. If your body connects the box to ground, this will trip the GFCI; but if your body connects the box to neutral, it won't trip. Moreover, the hot conductor to box fault could persist for a long time, long enough for a second failure to occur, such as the GFCI going bad. Then there would be nothing to protect you.
Cheers, Wayne
Wayne Whitney wrote in news: snipped-for-privacy@pizza.private:
It all makes sense. It could happen and probably has at some point and that's why it's required like so many things that may not seem to make sense.
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