#12 wire with 15 amp breaker

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jmattero

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Hello:
When re-wiring a home recently, I used #12 wire for a 15 amp circuit (a living room, bedroom lighting and receptacles circuit). I used a new 15 amp breaker in the panel, since I used 15 amp receptacles in the bedroom and living room, rather than 20 amp receptacles.

I have an aquaintainance, who is a union electrician, and he has told me that this is somehow dangerous, and against code. It seems to me that using #12 wire on a 15 amp circuit is MORE than what is required, and therefore, is absolutley fine.

Am I missing something????
 

Dennis Alwon

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What your missing is that you can use 15 amp receptacles for a 20 amp circuit unless it is a single outlet on an individual circuit 210.21(B)(1). Also look at Table 201.21(B)(2)
 

infinity

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A 15 amp OCPD in this application is fine with 15 amp devices and #12 conductors. I would have used a 20 amp OCPD since you already have the 20 amp conductors installed.
 

roger

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Am I missing something????
Yes, you are missing a code article from your friend. When someone says "blah,blah,blah, with no substantiation it is nothing but hearsay.

Read the code sections provided by Dennis, but he meant 210.21(B)(2) in the second section.

Roger
 

kwired

Electron manager
Location
NE Nebraska
You could have run 3/0 AWG and put it on a 15 amp circuit if you wanted. The difficulty of terminating both the breaker and devices is an issue as well as size of outlet box needed, but otherwise is ok to do so.
 

ceb58

Senior Member
Location
Raeford, NC
The thing your freind may be thinking is that some times, for voltage drop, some will run #12 to the first device and then change over to #14 all on a 15 amp ocd. Then someone comes behind them and seeing the #12 puts in a 20amp ocp. But that all falls into the "what if" catagory.
So its like Roger said.....

Yes, you are missing a code article from your friend. When someone says "blah,blah,blah, with no substantiation it is nothing but hearsay.

Read the code sections provided by Dennis, but he meant 210.21(B)(2) in the second section.

Roger
Hi, Roger
 

charlie b

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. . . an aquaintainance . . . told me that this is somehow dangerous. . . .
What does this person think is the source of the danger? The wire is being protected at its ampacity, the circuit is not overloaded, and even if a future electrician "mistakenly" switched the 15 amp breaker with a 20 amp breaker, that would not create a violation.

Is this aquaintance perhaps confusing this situation with the (equally legal) situation of a 15 amp breaker connected to #12 wire that is run some distance, and that is transitioned (within a junction box) to #14 wire before being finally connected at the load end? I have heard that second situation called dangerous, in the sense that a future electrician might make the mistake of switching the breaker to a 20 amp. But that would be an error by the future person, and would not be a code violation created by the original installer.
 

charlie b

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OK, I see that I typed too slowly again. I also see that persons with initials "CEB" tend to think alike. ;)
 

arnettda

Senior Member
What your missing is that you can use 15 amp receptacles for a 20 amp circuit unless it is a single outlet on an individual circuit 210.21(B)(1). Also look at Table 201.21(B)(2)

Can you put both 15 amp recepticles and 20 amp recepticles on the same 20 amp circuit? I went somewhere once where the bought a new coppier that was a 20 amp plug. The outlet where they wanted to plug it into was 15 amp. There were three other 15 amp receps on the 20 amp circuit. I replaced the one with a 20 amp and was on my way. Was I legal?
 

Little Bill

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Tennessee NEC:2017
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Can you put both 15 amp recepticles and 20 amp recepticles on the same 20 amp circuit? I went somewhere once where the bought a new coppier that was a 20 amp plug. The outlet where they wanted to plug it into was 15 amp. There were three other 15 amp receps on the 20 amp circuit. I replaced the one with a 20 amp and was on my way. Was I legal?

You can have both 15 & 20A devices on a 20A circuit. But you can't put a 20A device on a 15A circuit. Table 210.21(B)(3)
 

infinity

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I was referring to a receptacle, and according to the table I mentioned, you can't put a 20A receptacle on a 15A circuit.

Sorry I shouldn't have said device in this context, I meant to say "you can install one 20 amp single receptacle on a 15 amp circuit."
 

Little Bill

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Location
Tennessee NEC:2017
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Semi-Retired Electrician
I think Rob's point was that you can put a 20A receptacle on a 15A individual branch circuit, per 210.21(B)(1).

I see that, but I was trying to answer the OP's 2nd question about mixing 15 & 20A receptacles on a 20A circuit. You don't usually see single receptacles in a setup as he described.
All is good!:)
 

jmattero

Member
Thanks to all

Thanks to all

To all of you who responded... Thanks! I had forgotten to subscribe to this thread through e-mail notification, so I was not aware that anyone had answered the original question.
 
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