Combining GFCI Breaker and Receptacle in the same circuit

[Jim Woodward]

I am re-wiring my main bathroom and putting in an exhaust fan unit too. The bathroom has always been on a common lighting circuit and I'm putting it on it's own 20AMP circuit now. I have a GFCI breaker installed at the panel (I figure that this is a good thing)? I have had a GFCI receptacle over the sink area. Is it still a good idea to keep this receptacle as a GFCI, should I change it out for a standard duplex? Is there a code reason to keep or remove one of these devices from the same circuit? It seems redundant to me to have both these GFCI devices in the same line, and I also don't know that it's safe.

[John Gilmer]

It's "safe" but it can be a PITA if you trip it.

So long as you remember that you have the GFCIs in "series" then you should be OK. (IOW: when the local power goes off you attempt to reset the local GFCI and then go back to the main panel and reset then and THEN go back to the local GFCI.)

I believe the "test" function of the local GFCI should not trip any "upstream" ground fault detector.

I would let it be. When the local GFCI fails a test then replace it with a normal outlet (but TEST with a GFCI tester to ensure that the panel GFCI truly works.)

[toller]

Perfectly safe, but why not use the breaker on another circuit?

[ranck]

Personally, if you are going to wire the light to the same circuit as the outlet, I would forget the GFCI at the breaker and just keep the outlet GFCI. Then, wire the light *before* the GFCI in the circuit so that if you trip the GFCI you don't find yourself in the dark. Though really, I'd leave the light on the general lighting circuit and use the new circuit for the fan and outlet only. Then you can keep the GFCI at the breaker box and if it trips you only cut off the fan and not the light.

Bill Ranck Blacksburg, Va.

[Chris Lewis]

According to John Gilmer :

It could trip _either_ one (or even both), depending on which one trips faster. The test button is essentially coupling a resistor from the the line side of one conductor to the load side of the other, to force a (small) imbalance.

If you had a GFI outlet downstream of an AFCI breaker, on the other hand, it'll probably be the outlet to trip. AFCI's do have a GFCI "feature", but its sensitivity is around 30ma, and the outlet's sensitivity is 3-5ma, so the outlet will probably trip faster.

Whether you remove one or the other is really more of a "operational consideration". It's safer than a single one (if one fails, you still have the other), but reenabling it will be more confusing.

If you were going to remove one, remove the GFI outlet. Because the GFI breaker (probably) protects more and is (probably) inherently less likely to fail.

[John Gilmer]

Think about it. That would not create an un-balance up stream. It just trips the unit being tested. Now were the "test" button to cross a power conductor to ground .... (That's why a manual tester is used in addition to the "test" button: it actually creates a ground fault. The "built in" test only simulates the fault.

[Jim Woodward]

My thanks to all that responded to my question. Not knowing if it was a safe to leave both GFCI devices in place I had removed the GFCI receptacle in favor of the breaker. The NEC code jury seems to be out on this one, in terms of the exact and proper setup, but it is clear that bathrooms need to be protected. I believe that the GFCI breaker will afford protection to more devices and given that this is a bathroom, I think this is best. At least I know that what I was trying to do was safe and no harm would come from it. Thanks again.