NEC Q: Can you have multiple leads into one ckt breaker?

[Tom Bergman]

Turns out I'm one circuit short in my shop subpanel. I need another

240V outlet, but have no free slots, and can't solve my dilemma with half-heights (it's only an 8 slot sub). I also cannot fish to the location I want (without massive renovation) from another 240V receptacle (they're currently all dedicated circuits). My plan was to pull the sub and install a bigger sub to run the new circuit (it's easy to fish from the existing sub to the receptacle location). However, that involves a fair amount of work as well, but I'll do that if that's what the NEC spells out.

So the question is, in lieu of the bigger subpanel, can I simply put both circuits (existing + new) into the circuit breaker or can I make up a pigtail in the subpanel box so only one wire goes into the breaker? I'm guessing (been too long to remember) the former is a no-no (multiple wires under single screw) and have no clue about the latter.

Any of you NEC experts have the handy answer?

[Erik Ahrens]

You can not use the power panel as a splice/junction box. You can put a gutter or small 4x box on the side/top/etc and splice in there.

Erik

[Doug]

[e-mail] (Tom Bergman) wrote in news: [e-mail]:

I'm not an expert but I've done a little research in this area...Multiple wires to a breaker would be allowed if the breaker is listed for it. The breaker should say something on the label about 2 wires if it is. Some SquareD QO series breakers allow it for a certain range of copper wire, for example.

Splices in a panel aren't forbidden by the NEC. It comes down to whether or not there's room in the panel to do it safely. If you have to get an inspection it's probably up to the inspector.

Another possibility would be to break the line to one of your existing receptacles and add a couple of junction boxes to allow an extension to your new location.

Pedantic nitpick...you mention adding another "circuit". Neither of these wiring methods will give you another circuit, just another receptacle on the same circuit as the existing receptacle. You won't have the additional capacity a new circuit would provide.

Doug

[Wade Lippman]

I agreed with you on the splices and the multiple wires, but you lost me on the pedantic nitpick. A circuit is everything between the breakers and the outlets. Two circuits can share one breaker. Now if he were to splice the two circuits together, rather than double wire the breakers, I might agree with you.

[John Sellers]

It's still only one circuit. It's just semantics of routing.

One breaker - one circuit.

John Sellers

[Doug]

"Wade Lippman" wrote in news:dUAsb.10325$ [e-mail]:

I think I see what you're saying from a schematic view but I don't believe that's the common definition of a circuit as used in AC wiring around a house. A circuit is usually everything controlled by a single breaker. Typically when someone speaks of adding a new circuit they want additional capacity for running more stuff at the same time. I only brought it up because none of the wiring methods we were discussing accomplished that.

Doug