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2 breakers wired to a single circuit

Posted by david5687 (My Page) on
Mon, May 17, 10 at 21:01

I'm doing some renovation work and have encountered a strange situation (to me) while mapping out the main breaker panel.

On more than a few outlets and lights, two circuit breakers must be on for the outlet or light to be "on". This is not for all circuits, but for well more than 1/2 of the house at 120V, including my swimming pool pump (240V). There are two circuit breakers marked "main lights" in particular in which one of them has to be on in conjunction with another one on the panel which seem to be the main culprits.

My question is, how concerned should I be with this wiring? Is it normal/acceptable? The house was constructed in 1927 and is a mixture of K&T and Romex. The dual breaker situation seems to exist in both types of wiring.


Follow-Up Postings:

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RE: 2 breakers wired to a single circuit

While your panel could really be wired incorrectly, it also is possible that it is a "split bus" in that most/all of the 240 volt circuits have no main disconnect but the 120 volt circuits do have a main disconnect ahead of the individual circuit overcurrent protection. The result is that disconnecting all loads in the panel might require operating up to 6 circuit breakers. The NEC in 1984 changed so that split bus is no longer used for new installations but existing split bus installations are not required to be changed so long as they are in good condition.


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RE: 2 breakers wired to a single circuit

As BUS points out "MAIN LIGHTING" is a common label for the feed to the "bottom" half of these split bus panels. (The assumption is that the other stuff on the "top" half are things like stoves, dryers, and other larger loads).


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RE: 2 breakers wired to a single circuit

On first reading I took this to be multi-wire branch circuits where two hots go out and one neutral returns. If the two breaker handles are tied together both would be switched on or off. This would account for the mention of the swimming pool pump.

Just my take.


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