gfci
How to GFCI-protect a 3 gang box where each receptacle is on a different circuit.
There's a 3-gang box near my kitchen sink. In it is a light switch, the garbage disposal switch, and an outlet. All of these are on different circuits (with the disposal on a dedicated circuit).
Is there a way to project all of these with a single GFCI, or do I need to replace all three with GFCIs?
Ok I read your question a few times, so hope I understand what you want to do. You want GFI prtection on the outlet , but no GFI protection to the fridge. This will be easy to do if you can affirm that the load wire leaving the j-box where the switch and outlet are located, is actually the feed for the fridge. To check this out, you need to turn off the power, check the outlet at the sink and fridge to be sure they are ,in fact on same circuit and off. Now disconnect all the wires from the outlet and any wirenuts so everything is isolated. Now, carefully turn the power back on and check the hot (typically black) leads to ground with a volt meter to determine which one is the feed/source wire. Mark this with some red electrical tape. Double check to see that the fridge outlet is still dead.
Next, turn off the power and wire nut the black source wire and associated white neutral to the black and white wires you suspect goes to the fridge.( black to black, white to white) Turn the power back on and check with your voltmeter at fridge outlet again. If there is voltage there now, you have found the right feed wire to the fridge outlet. An alternate method of finding that wire with the power off, is to use an ohm meter. Assure the power is off, then twist the black and white together on the wire you suspect goes to fridge and check the hot and neutral slots of the fridge outlet with your ohm meter. the meter should show 0 ohms or "short circuit".
Now that you have identified the hot feed and load wire to fridge in your box, you can wire it so only the counter outlets are GFI protected. Put the source black wire together with the fridge black wire, along with a separate 8 inch piece of black wire (pig tail) and wire nut them all together. Use the 8 inch black wire to feed your switch/gfi hot. The neutrals tie together as usual with an extra pig tail for your GFI outlet neutral. Obviously, trim the pig tails to a comfortable length to fit in your box before connection to the GFI.
Since all outlets must be GFI protected in the counter outlet and since you cannot split a gfi outlet top and bottom like in your diagram, you have to do your light differently from your previous plan. I would suggest using a switch/single outlet device wired from the load side of the gfi. Wire the switch in series with this single outlet. This means only the single outlet is switched and gfi protected. You must have gfi protection on this outlet, as someone could unplug the lights and use it for something else.
Hopefully, one of my artistic buddies can do an edit and add a nice diagram depicting what I have outlined for you.
First things first, here's a link to Leviton's 7299 combination switch & GFCI instruction sheet. For a tamper proof it will be a T7299. The only reason I give Leviton is because I know the part number. Hubbell, GE or Cooper are just as good and make the same.
GFCI protection for both outlets.
Follow the instructions that come with the GFCI. There are leads for the switch and lugs for the GFCI and also the feedthru-protection of another receptacle.
No GFCI outlet behind the dishwasher (for easy resetting without dishwasher removal).
This is accomplished by feeding the dishwasher receptacle using the GFCI feedthru-protection lugs.
The switch only toggling the garbage disposal outlet and not the dishwasher outlet.
This is accomplished by using the leads on the combo switch & GFCI to feed the garbage disposal.
Am I going to need to run some more wire through the walls?
If there are no wires between the combo switch & GFCI then you will have to pull some romex between the two.
Should I investigate adding a GFCI breaker for that circuit?
The breaker will cost a lot more than the combo switch & GFCI. Also, if the GFCI trips then you have to go to the breaker to reset it. At least with the GFCI receptacle feeding your dishwasher receptacle, you will be closer.
What other solutions would achieve the same effect as listed above?
I think this is the way to go, so you don't have to pull your dishwasher out to reset the GFCI. The nice thing about this site is some of the people either can think out of the box or have faced this problem before.
Best Answer
First, "GFCIs", it sounds like you are talking about the "GFCI + receptacle combo device" readily available all over. While that is one way to provide GFCI protection, it can also be provided by a GFCI device upstream. Any GFCI device can protect all downstream loads. As such, GFCIs come as
So for instance, providing GFCI protection to a switch obviously can't be done by a GFCI+receptacle combo device at the switch location. You need to find an upstream location and install a GFCI device.
You said "GFCI protect your 3-gang box", and it doesn't work that way. Boxes don't get GFCI protection, outlets do. (an "outlet" includes any electrical tap, including hardwired loads such as a light or disposal). This box has a mix of things that do, or do not, need GFCI protection. Lighting generally doesn't need GFCI protection. A disposal may, but putting it downstream of a switch is bad form, as some GFCI devices don't like their power being interrupted. The better location for that GFCI device is upstream of the switch.
Home inspectors are particularly awful about spreading this "GFCIs are receptacles" myth. . If they don't see a "Test" and "Reset" button, they tell you it needs a GFCI there. This is why "GFCI protected" stickers are required on plain receptacles whose GFCI protection is sourced from upstream. Unfortunately, some people consider them unstylish, and tear them off. Get more. You can also make them with a labelmaker, they need not be blue.