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Help with DIY dedicated circuit

I am wanting to install a dedicated circuit for my amp, but getting from my panel to the wall behind my amp is going to be difficult. As I was investigating in my attic, I realized that when I changed my stove from electric to gas, the unused 30 amp Romex 10/3 wire will reach within 15 feet of where I want the wall outlet. Do I install a junction box and run Romex 10/2 to the new wall outlet and use the 30 amp breaker? What is the best way to connect the wires in the junction box?
jonandfamily
djones51
617 posts
 
You're not suppose to use the same neutral wire for 2 seperate breakers you can for a double pole since any overload on the neutral will trip both. 
djones51
617 posts
 
You also need to make sure the new 20amp  double pole is on different phases in the panel box. It should be if the old 30amp was installed correct. 
jonandfamily's avatar
jonandfamily OP
76 posts
 
pbnaudio....the physical wire connections are not what I'm asking about. I am comfortable with that. I'm asking whether to use the 30 amp twin breaker and the 10/3 cable that is currently in place (too short to reach wall outlet) with a piggytail from a junction box I'll install to the outlet, or I'll have to pay significantly more to have an electrician run a new 20 amp line from the panel to the wall. Also, could I install 2 independent outlets without running a separate cable since there are 2 hot cables with the 10/3? It appears best to change the 30 amp twin breaker to a 20 amp breaker since it will be serving a 20 amp rated outlet.
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jea48
2,944 posts
 
mental522

@djones...you are very mistaken, he’s running two circuits using the same neutral. Two single pole breakers should be used, one for each circuit. A double pole breaker is designed to use different phases, all he has to do is put the single poles back in where the double pole is. I suggest you stop giving out electrical information, you are clueless.

@mental522
The National Electrical Code permits multiwire branch circuits, but adds requirements to make them safer. Section 210.4(B) states that in the panelboard where the branch circuit originates, all ungrounded conductors must be provided with a means to disconnect them simultaneously. This is usually a double-pole breaker, but two single-pole breakers may be used if they have an identified handle tie.
https://www.jadelearning.com/multiwire-branch-circuits-nec-210-4/

Mike Holt on multiwire branch circuit
https://www.youtube.com/watch?v=_VjZ5ySblew
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