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There are 4 single pole breakers in the 220v main panel and 2 white wires on the neutral bar (I am assuming it is a common neutral situation). Two breakers have a black wire and two have a red wire. The black wires are on the same leg while the red wires are on the other leg. Is this correct? Sporadically there is a circuit outage on only one circuit lasting from a few seconds to a couple of minutes.

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No. The two black/red wires that share a neutral are part of the same circuit, and the formal name is a multi-wire branch circuit (MWBC). either

  • the two breakers need to be fitted with a listed handle-tie for that breaker type, which as a side-effect will force them to be on opposite poles; or
  • the two breakers need to be replaced with a 2-pole (240V) breaker of a correct type for that panel. By nature a 2-pole breaker puts its 2 lugs on opposite poles.
    • The 2-pole breaker may be of GFCI, AFCI or GFCI+AFCI type. If so, it will confer protection to the entire MWBC.

Listed, correct handle-ties can be annoyingly hard to find, so in most cases just use 2-pole breakers which are available everywhere.

A double-stuff/duplex/tandem/twin breaker is not a 2-pole breaker and the essential clue is that the handles are not tied and cannot be tied.

The purpose of handle-tying is to assure common maintenance shutoff. It is not essential for MWBC breakers to be common trip, but using a 2-pole breaker will have that effect too.

If you are stuck with a crowded panel using double-stuff breakers, then handle ties are usually not an option. Go with quadplex breakers instead.

  • The black wires are on one pole and the red are on the other. This was a box put in 20 yrs ago. – Paul Oct 6 '18 at 0:49
  • The wires sharing the neutral are the black (attached to a single pole breaker) that is on one service leg and the red (attached to another single pole breaker) is on the other leg. Is this consider on the same circuit? – Paul Oct 6 '18 at 1:17

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