GFCI Question

I know there is no functional reason for doing it but can anyone tell me specifically what the electrical code states about 2 GFCI outlets being wired on the same branch circuit. I’ve been flagging it in the building I’m working in but the electrican is telling the GC it’s O.K.

More than one GFCI receptacle on a branch circuit is an acceptable practice. As a matter of fact, one GFCI receptacle installed upstream can protect other receptacles in the same circuit. If you have been flagging bathrooms which are sharing one GFCI circuit, then you are right to do so, since common sense says that Mom and Sis using hair dryers at the same time will cause nuisance tripping. NEC says, one each for the kitchen, laundry, each bath, exterior, and garage. Sometimes I step out there when I don’t have “the book” handy, like right now, so maybe someone can step in and confirm the above…it may be ok to combine exterior and garage on one circuit.

Actually, that is not correct. Bathrooms can (and commonly do) share a GFCI protected circuit. The NEC does not say “one each” for the areas you listed. It simply says that these circuits shall have GFCI protection.

The original question asks about multiple GFCI receptacles on a single circuit, to which the NEC makes no comment. Other than creating a nuisance, there is nothing that prohibits this practice.

I will often recommend removing additional GFCI receptacles when I run across this condition.

Thank you both for your response.

The particular issue was in the master bathroom. There are only two outlets and they are both GFCIs and they are on the same circuit.

No violation or hazard… just wasteful of material. No big deal. It is possible that even though they are both on the same circuit, they are each “pigtailed”. This way, if one GFCI tripped or failed, the other GFCI would remain functional. If the second GFCI is, indeed, installed downstream of the first (on the load side), it’s just wasteful but not hazardous.

How about four GFIs on one circuit?
My home was wired with two bath receptacles and two outside receptacles on one GFI breaker. Not the best layout but perfectly legal for the day.

I did not like the thought of going out to the garage to reset a tripped GFI breaker so I installed GFI devices, all wired to the line side, at each location.

Ocassionally you will see one gfci protecting another, is this what you mean? I heard once that this setup will cause nuisance tripping, but I have never verified it. It is usually done in error by a non qualified installer.

It won’t cause nuisance tripping, but it certainly doubles your possible chances of having a nuisance trip, since there’s twice as many GFCI devices protecting that second receptacle. When I find “double GFCI protection”, there’s usually already a GFCI breaker in the panel, and the homeowner installed GFCI receptacles in the common places, thinking they were making some enhancement. Many people don’t realize that GFCI breakers exist, and they’re used to seeing the more popular point-of-use GFCI protection.

I use “doubled up” protection all the time these days. I an the new dock master in my community and when I am working on the docks I use homeowner’s outdoor receptacles for my power tools but I always use my GFCI adapter on the cord.

In the construction trades, it is company policy for many companies that their workers use the GFCI pigtails at the head end of their cords. This is without regard to whether the workman believes he is plugged into a GFCI protected receptacle. Makes good sense, particularly when it’s your life on the line. You can be reasonably sure of the condition and status of your own GFCI pigtail cord, but you can’t always be certain of the condition of an existing GFCI receptacle or bother to take the time to check. Use you own, and you’re covered.

**“You can be reasonably sure of the condition and status of your own GFCI pigtail cord, but you can’t always be certain of the condition of an existing GFCI receptacle or bother to take the time to check. Use you own, and you’re covered.” **

Good advice, Mark.

With 23+ years in inspection, I’ve generated my own report and appendix. In the Appendix GFCI section, I now recommend that before using a GFCI protected receptacle, trip and reset it a couple times, even if you have to walk to the panel or other location to do it.

Why? Over the years, as they get older, I find more and more not tripping (especially outdoor units) when tested although they show themselves to be energized and properly wired with my Suretest. It must be internal corrosion seizing up the trip mechanism. Just because there’s power does not mean the unit will trip when needed.

The other thing that happens is that they will trip once and not be able to be reset…maybe close to a failure waiting to happen.

That’s why the manufacturer’s say: **TEST MONTHLY
**

Thats the OPTIMUM verbage for that statement…lol…legal for the DAY…or that period in time…:slight_smile:

Customers look at me goofy when I show up to troubleshoot a non-working garage or outdoor receptacle and I ask them to show me where all their bathrooms are. Back in the day, the GFCI that was protecting the whole shebang could be anywhere. As was pointed out, it was legal to do so then.

Yep…and why I said…Legal for the Day or that period in time…I was not yankin on Speedy…I AGREED with him.

I see this all the time as well…

I know, I was just adding some extra commentary. I have a fat head, and if I don’t type a certain amount of information each day, my head will explode. It’s just a health concern. :mrgreen:

lol…It’s all good…I prefer to call what I have a FAT BRAIN…but it’s all good.