# 12/3 connected to 12/2 and 14/2

Greetings,
I would like to confirm that, according to the NEC, there is no reason why you cannot use 12/3 connected to 15 and 20 amp breakers (one on pole A the other on pole B) and then (say 30 feet away) branch into two circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2).
Thank you for your time and energy, William
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Definately WRONG.
You cannot use 14 anything on a 20 amp breaker in any case.
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Dear Noozer,
Thank you for taking the time to answer but please first take the time to read the post.
Thanks, William
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William-
Personally I was not able to understand it clearly enough to answer it.
So unless you are willing to restate your original question more clearly I sincerely doubt you will get a better answer.
:"I would like to confirm that, according to the NEC, there is no reason why you cannot use 12/3 connected to 15 and 20 amp breakers (one on pole A the other on pole B) and then (say 30 feet away) branch into two circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2).
So does this mean you're:
running 12/3 from a 15 amp breaker & also running 12/3 from a different 20 amp breaker
or have you created a shared neutral situation?
???
and then ~30ft away "branch" (branch what or which; each original circuit ?)
into two two circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2)
is each original circuit be branched or just one of them? do you intend to install the proper sized breakers to protect the 14/2?
bottom is 12/2 ok on 20 amp breaker, 14/2 is only ok when protected by a 15 amp breaker
why the mixed breaker & wire size?
Just run it all in 12/3 & simplify your life.
cheers Bob
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Greetings,
I have attempted to add clarity with the description below:
In the breaker box I have two single pole breakers. One breaker is 15 amps. One breaker is 20 amps. The 15 amp is on pole A. The 20 amp is on pole B. There is a 30 ft piece of 12-3 attached to these breakers. (*creating shared neutral situation) The 15 amp is attached to the red wire. The 20 amp is attached to the black wire. At the other end of the 12-3 there is a utility box. In this utility box the red and white wires have been attached to a piece of 14-2. In this utility box the black and white wires have been attached to a piece of 12-2. Is this a code violation?
Thank you very much, William
Some responses to specific questions asked as follows: Q: why the mixed breaker & wire size? A: to reduce voltage drop to < 5%. The portion of the run already in 14-2 is buried UF and would be a REAL pain to change.
Q: Any person working in your panel would have no way to know that the 12 awg had been reduced somewhere downstream A: They would suspect/know because it was attached to a 15 amp breaker
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snipped-for-privacy@wdeans.com wrote:

You're worrying about it too much. What you have is legal and reasonably safe. It would be better if the breaker handles were tied together, or if you used a 2-pole common-trip 15A breaker instead of a 15 and a 20 (of course not knowing the load you have on the 20A side, a 15A breaker might not be enough)
Best regards, Bob
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Based on what I hear I am going with it (unless I hear different from someone who can site what code I am violating.)
The 20A load is for a bathroom / laundry room and is required to be 20A by code (or else I would have to run another 20A circuit). The 20A breaker is a standard sized breaker the 15A breaker is a mini-breaker so I am not sure I could even purchase a tie bar if I wanted to.
Thank you all very much.
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Doesn't the NEC specify that a single, dedicated 20A circuit is required for the washer/dryer receptacle? Or you already have that in place and are running another 20A circuit for the bath portion?
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There are 5 circuits in the bathroom / laundry room (same room): a) double pole 30 amp for the drier b) 20 amp dedicated recepticle for washer/drier c) 20 amp (other recepticles) d) 20 amp heater e) 15 amp lighting
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And "C" is GFCI, right?
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C) is a GFCI receptacle on a NON GFCI breaker. Other receptacles on same circuit are on the feed-through.
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Thats all you need.
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You could also mark the breaker and note in the breaker box that the circuit is wired in part with 14/2 so no breaker larger than 15amps should be used. Won't prevent someone from adding a larger breaker that's determined, but it should stop most people. Hopefully the load required from the outlet(s) at the end of the 14/2 branch will be less than 15 amps in total. You can't always save people from themselves. It is entirely possible for someone to put a larger than 20 amp breaker on the circuits wired with 12/2-3.
David
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You absolutely cannot do that. Any person working in your panel would have no way to know that the 12 awg had been reduced somewhere downstream and in doing a service upgrade for example would install the wire to a 20 amp breaker

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Actually, code specifically allows it. 210.3 "where conductors of higher ampacity are used for any reason, the ampere rating or setting of the specified overcurrent device shall determine the circuit rating". This is frequently done where there is a long run from the breaker box to the first outlet and there might be a voltage drop problem.
But unless you have a good reason to do it, it probably is best to be consistent.
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would have

downstream and

20 amp

higher
the
box to

be
Agree...
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Putting a 12awg on a 15amp breaker is not the problem. Reducing the wire size downstream is!!

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Dear RMB,
I am reducing the wire size downstream from 12 to 14 AWG on the 15 amp breaker for the portion of the circuit without a shared neutral (see full description previously posted). Based on what others say there is no code issue here. Your argument that later no one will know not to put a 20 amp breaker in in the future is false. They will know because there is currently a 15 amp breaker installed so they need to find out why before switching to a 20 amp breaker. You just can't go replacing 15 amp breakers with 20 amp breakers or 20 amp with 30 amp based on the wire size entering the main panel. Unless you can provide some other argument for your statement other than the debunked argument above I am going to proceed as planned.
Thanks, William
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William I don't have a code book handy, but I can assure you that your assumption is incorrect. Reducing wire size downstream in the manner you describe is illegal. Hopefully someone like Horne will pick this up and direct you to the proper code section

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On Thu, 16 Jun 2005 18:23:05 -0400, "RBM" <rbm2(remove

I use a code book every day and I do have one handy. I will be anxiously awaiting the reason "reducing wire size downstream" is illegal.
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