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I have kitchen outlets that have one breaker powering the top outlets, and a separate breaker powering the bottom outlets with the tab broke off on each outlet. There are a total of 7 different outlets wired up the same way.

I wanted to have the outlet GFCI protected but did not know how I could use GFCI outlets and have the top of bottom of the outlets be powered but two different breakers. I bought two 20 amp GFCI breakers to change out the original breakers.

That is when I found out that I had one 12/3 wire with black, red, white, and ground wires. I tried to use two different GFCI breakers by trying to wire nut two wires off of the white wire so that I had a white for each GFCI breaker. When I turned on one of the breakers it was fine, but when I turned on the second breaker it tripped both breakers.

I thought that I might have to buy a double pole 20 amp GFCI breaker in my situation to make this work. I am not positive how double pole breakers work.

  • Will I then have 240 volts instead of 120?
  • Do I have to check every outlet to make sure they did not have black and red on same top or bottom circuit?
  • Will I have 20 amps off of each side?
  • Are these two breakers next to each other in the panel? Can you upload a picture of the panel? – manassehkatz-Moving 2 Codidact Jul 20 at 20:49
  • The breakers are in 1 and 3 in the panel. I cannot upload a picture at this time. – Keith Keller Jul 20 at 21:54
  • @KeithKeller -- hit edit in the "share edit ..." under the left of your post (below the tags) and then use the "mountain and sun" button to add photos – ThreePhaseEel Jul 20 at 23:27
  • Are either the top outlets or the bottom outlets switch controlled? – FreeMan Jul 21 at 12:25
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    @Freeman - no outlet is switch controlled - they are hot all of the time. – Keith Keller Jul 22 at 21:56
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I wanted to have the outlet GFCI protected but did not know how I could use GFCI outlets and have the top of bottom of the outlets be powered but two different breakers.

You can’t make a GFCI receptacle work that way. It can only protect one 120V half-circuit; you have two.

To do this with GFCI receps, you would need seven of them, and each one would be on a different circuit (i.e. both sockets on the same subcircuit).

That is when I found out that I had one 12/3 wire with black, red, white, and ground wires. I tried to use two different GFCI breakers by trying to wire nut two wires off of the white wire so that I had a white for each GFCI breaker. When I turned on one of the breakers it was fine, but when I turned on the second breaker it tripped both breakers.

Yup, that can never possibly work. That is not how GFCIs function. They are comparing the current on the hot to the current on the neutral. If they are different, current is leaking somewhere. So from each individual GFCI’s perspective, current via the other GFCI is a ground fault, and they must trip.

I thought that I might have to buy a double pole 20 amp GFCI breaker in my situation to make this work. I am not positive how double pole breakers work.

Yeah, and I bet you’re getting real sick of spending $100 over and over on things that don’t work. Good reason to ask!

However the 2-pole GFCI is the right solution for this.

A 2-pole GFCI monitors all three wires, assuring the currents are equal (or to be more precise, net out to zero... counting outbound current as equal and opposite to returning current, on whichever wires it may occur). Now, neutral is not bypassing the GFCI so all neutral current is being correctly counted.

By the way, if working with and replacing outlets, never splice the neutral wire on the outlet. Neutral must always be pigtailed.

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  • Why must neutral always be pigtailed? – Matthew Jul 22 at 15:48
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    @Matthew Because it’s a MWBC (Multi-Wire Branch Circuit). You have to pigtail because you’re not allowed to use a device/equipment to continue the neutral wire (i.e. the 2 screws on a recep). You have to be able to remove a device without breaking neutral for the other half of the circuit. That rule probably seems obsolete given a 2-pole breaker and a GFCI to boot, but it’s still a rule. – Harper - Reinstate Monica Jul 22 at 18:00
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This sounds like a multi wire branch circuit and putting a GFCI receptacle on one side or even the other tends to have problems unless only the line side s used. Using only the line side and having each receptacle protected by the its own circuitry then alternating from black line to red line is the best way to not have unwanted trips but will be more expensive because of the extra GFCI receptacles required. In most cases it will take 4-6 extra gfi receptacles under 100$ to retro fit many kitchens with no false trips. I have tried to use double pole GFCI breakers and found the best method for GFCI protection on a multi wire with the least trips was each receptacle fed from the line side ether 2 wire or 3 wire both will be protected with maximum protection.

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