Im a Licensed Contractor and very comfortable with working on electric. That being said, my new home had underground 200 amp service and we could not disconnect the power so I used a licensed electrician to replace the exterior meter box that had rotted and install a new D Square 200 amp QO box (so I didn't have to work with the live 200 amp wires..). I thought he did a fantastic job looked clean and functioned great. Inspector came and Failed it, part one was for not replacing a piece of sheetrock next to the box (I left it off so he could see everything... Easy fix thought). The second Part stated "Multi Wire Circuits 2P CB on a approved tie Bar". I have no idea WTF this means lol. I wire outlets/lights and occasionally add a breaker for a new line. When I asked the inspector what this means he stated that the electrician would understand and it would take him 10 minutes to fix... My electrician bailed on me & won't return phone calls. I'd rather not call in a second electrician for something I'm sure I can fix myself. If anyone has any insight, please let me know.

Side note: All my wires in my house are BX with the exception of one is Romex added years later. My box does not have a separate ground bar in the box instead he tied the neutrals into the left side of the box and tied the grounds into the right. I was thinking the inspector wants a separate ground bar in the box the BX neutrals are fine on the left and the 1 Romex wire he wants that neutral on the Right. I

Breaking down what the Inspector said "Multi Wire Circuits 2P CB on a approved tie Bar" I presume means Multiple wire circuits 2 Pole on Circuit Breaker on approved tie bar? I just don't know what this means needs to happen to fix the problem lol

Thanks in in advance hope I explained this well enough.


  • Can you post photos of the panels involved? Nov 24, 2018 at 0:30
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    Just from the words ""Multi Wire Circuits 2P CB on a approved tie Bar" I think means that the multiwire circuits are on two separate breakers and there must be a metal link (tie bar) that connects the breakers so that you cannot manually turn off only one breaker of a multi-wire pair. electric supply will have the links for the breakers you have. Nov 24, 2018 at 1:07
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    @JimStewart not metal. Listed. CH ones are plastic and CH beige, naturally :) Nov 24, 2018 at 1:29

2 Answers 2


Heres my guess. It's an easy one indeed. By "multi wire circuit" he actually means multi-wire branch circuit. This is a special method of running 120V circuits where you get 2 circuits' worth of power on one /3 cable, by sharing neutral. You can google it, but the highlights inspectionwise are

  • the circuit must have neutral pigtailed, you can't use a receptacle etc. as a splice point for the onward neutral or you'd knock out both sides of the circuit if you removed the device.
  • Both legs must, must, must be on opposite poles.
  • both legs of the MWBC must have common maintenance shut-off, so the usual technique of "turn breakers off until the radio stops playing" turns off the whole circuit.

That last one is what you are being written up for.

In a residential breaker panel (as opposed to fuses or industrial), you do that one of two ways. You use a 2-pole breaker (like you would for a water heater, but the correct amperage)... Or you use listed "handle ties" that are correct for that breaker type. These are weird and specialty, and big-box rarely carries them. Sourcing them is such a hassle that I just advise people to use 2-pole breakers, which are sold everywhere for $10. This also leads them into correct decision making when selecting AFCI or GFCI breakers later.


So you need to search your panel for circuits which have 3 conductors, not including ground: two hots and a neutral. In a panel like yours with all cables, the dead giveaway is a red wire for the second hot.

Follow each of them, and make sure every one lands on a 2-pole breaker. If you find a pair going to two singles, measure the voltage at the breaker between the two "hots". It had better be 240V. If it's not, congrats, you just dodged a house fire. Move those two "hots" to a 2-pole breaker of same amp rating.

The reason I advise 2-pole breakers in your case (besides the annoyance of finding listed handle ties) is that way, you don't even need to chase it to figure out if it's an MWBC. 2-pole breaker, done...

  • Amazing to both of you. The vague orange sticker on my box now makes sense lol! Than you guys very much. Im going to Home depot now to buy a bunch of them and change them out in the morning. Nov 24, 2018 at 1:35
  • Just to get one more thing straight, don't 2-pole breakers come in two types--common trip and independent trip? (In the latter type an over-current event at only one breaker trips only that breaker, leaving the other breaker and its circuit still powered.) Both types have common manual shutoff. For a multi-wire branch circuit would one want an independent trip or a common trip? What is best practice and what is code on this? Nov 28, 2018 at 13:15
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    @JimStewart -- most bog-standard 2-pole breakers are common trip these days, as those are usable everywhere, while independent trip 2-pole breakers are only useful for a limited subset of the times you'd use a 2-pole breaker (they're only good if you either have a single load on the circuit, or are solely powering line-to-neutral aka 120V loads), and can readily be constructed using two 1-pole breakers and a handle tie anyway. (There are some legacy quadplex part numbers in the Eaton BR line that are independent trip, but that's all I know of) Nov 28, 2018 at 23:56
  • @ThreePhaseEel: From what I've seen, some breakers have powerful enough "trip" springs that if securely tie-barred, a trip on either will shut off both, but not all do. I would think that having just one side trip would be likely to create a hazardous condition since a momentary high current draw on the non-tripped side could create a significant voltage potential on the "seemingly disconnected" trip side.
    – supercat
    Dec 25, 2019 at 16:52
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    @supercat accidental common trip of handle-tied breakers often happens, like your mashed potato gravy often gets into the peas and carrots. The whole point is that common trip is not guaranteed. As far as safety, the cases where you imagine it to be unsafe are the cases where it is disallowed. There, 2-pole common-trip breakers are mandatory, for that very reason! I have become expert on this because I have a glut of 30A 1-pole breakers, which are good for little else. Dec 25, 2019 at 17:03

In our area two separate one pole breakers properly tied together is no longer acceptable for multiwire circuits. An actual 2-pole breaker is required. This breaker is tied together internally thus ensuring that one side cannot be shut-off without the other. Good Luck. PCL

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    Can you add where your area is? This sounds like a local amendment to me... Nov 24, 2018 at 18:00
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    @ThreePhaseEel I can vouch for PCL. I know of at least three municipalities that have disallowed handle ties and require internally locked 2-pole breakers. Remember it's always up to the AHJ and they really don't like arguing about it. Nov 24, 2018 at 22:45

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