12-2 to start 15a circuit

[BobbyRay]

Re: 12-2 to start 15a circuit

The reason I asked about the 12-2 home run on a 15a circuit, was to find out if anyone can site this in the code and where it is in the code. I think this is bad practice because alot of people know just enough about electrical to be very dangerous, if someone like that works on a panel that the wires are not clearly marked, it could be a problem. You can try to make it fool proof but you cant make it DAMN FOOL proof.

 

[iwire]

Re: 12-2 to start 15a circuit

Originally posted by BobbyRay:
The reason I asked about the 12-2 home run on a 15a circuit, was to find out if anyone can site this in the code and where it is in the code.

What are you looking for?

The NEC does not prohibit using 12 AWG on a 15 amp circuit.

Regardless of how you feel about it, it is a common practice for many of us.

 

[roger]

Re: 12-2 to start 15a circuit

Originally posted by BobbyRay:
The reason I asked about the 12-2 home run on a 15a circuit, was to find out if anyone can site this in the code and where it is in the code.

It is not in the code because it is a necessary wiring method, Think Voltage Drop.

I think this is bad practice because alot of people know just enough about electrical to be very dangerous, if someone like that works on a panel that the wires are not clearly marked, it could be a problem.

These people have no business sticking their grubby paws in the wiring.

You can try to make it fool proof but you cant make it DAMN FOOL proof.

You need say no more.

Roger

 

[physis]

Re: 12-2 to start 15a circuit

Some unqualified person could always come along and do something to make an installation unsafe. If they can't do it buy putting a 20 amp breaker on 15 amp conductors they can find another way. You can't make enough codes to stop them.

I think it's a good idea to mark the circuits.

 

[iwire]

Re: 12-2 to start 15a circuit

Originally posted by physis:
I think it's a good idea to mark the circuits.

Wuss


Just kidding you, it's hard to say labels are ever a bad idea.

 

[electricmanscott]

Re: 12-2 to start 15a circuit

Originally posted by mc5w:


One of the reasons for banning 15 amp wiring is that is the only way that some places can get electricians to put 20 amp wiring into the kitchen, laundry, bathroom, and dining room.

Yeah I guess that's one way to do it. Sane people can just enforce the code. :roll:

 

[physis]

Re: 12-2 to start 15a circuit

)

By Bob:

Originally posted by physis:
I think it's a good idea to mark the circuits.

Wuss

I'm not that much of a wuss. I probably don't mark things as often as I think I should.

Edit: Fixed UBB code.

[ July 20, 2005, 04:38 PM: Message edited by: physis ]

 

[roger]

Re: 12-2 to start 15a circuit

Although marking may be a good idea, any one that would upsize an OCPD with out knowing what was on the other end, most likely can't read. :roll:

Roger

 

[augie47]

Re: 12-2 to start 15a circuit

An electrician should know better than to change the OCP for a circuit with out knowing how the circuit is wired.

I agree, but I fear in this area if an "electrician" goes on a service call with a 15 amp breaker tripping and finds a #12 wire, he will routinely just change it to a 20 breaker without checking every inch of the circuit to see if #14 is involved.
Due to the desire/need to install #12 for voltage drop situations, in this area the inspectors will accept #12 home runs on a 15 amp circuit if the wire is suitably tagged at the breaker to indicate a 15 amp circit. (some inspectors require a #14 "pigtail" at the breaker)

 

[iwire]

Re: 12-2 to start 15a circuit

Originally posted by augie47:
in this area the inspectors will accept #12 home runs on a 15 amp circuit if the wire is suitably tagged at the breaker to indicate a 15 amp circit. (some inspectors require a #14 "pigtail" at the breaker)

Again unless there are local amendments an inspector can not require tags or the pigtail.

This is allowed by the NEC without any special provisions.

 

[roger]

Re: 12-2 to start 15a circuit

Augie,

I agree, but I fear in this area if an "electrician" goes on a service call with a 15 amp breaker tripping and finds a #12 wire, he will routinely just change it to a 20 breaker without checking every inch of the circuit to see if #14 is involved.

are you sure you want to call them electricians?

BTW, see Iwires last post on page 2 for a point of interest.

Roger

[ July 20, 2005, 05:47 PM: Message edited by: roger ]

 

[iwire]

Re: 12-2 to start 15a circuit

Thanks Roger, I will move it up to the new page.

Originally posted by iwire:

Originally posted by augie47:
in this area the inspectors will accept #12 home runs on a 15 amp circuit if the wire is suitably tagged at the breaker to indicate a 15 amp circit. (some inspectors require a #14 "pigtail" at the breaker)

Again unless there are local amendments an inspector can not require tags or the pigtail.

This is allowed by the NEC without any special provisions.

 

[LarryFine]

Re: 12-2 to start 15a circuit

Originally posted by allenwayne:
Several years ago I did a house in a high line subdiviion called Cheval,over 12,000 sq ft single story. The homeowners wanted all the panels 3 of them to be in the garage. The house was shaped like a giant V. Wouldn`t you know it but the kitchen offices(dedicated computer circuits etc.)
were on the opposite end of the house. Some runs were artound 250-275 ft.

This is a prime example of the need for a sub-panel or two. We're wiring a fairly large house (around 8k'sq), and I ran a pair of 100-amp sub-panels to the far side of the house (in the basement).

I explained to the HO about the performance of the electrical supply, load diversity, and voltage drop, and he agreed with the idea. Except for the hot tub, the bedroom end of the house, HVAC included, is fed from the sub-panels.

The reason for two sub-panels is that we have two main panels, one fed through the generator ATS, and the other straight through, and split the circuits between the panels according to the desire to have generator power for some.

 

[flip]

Re: 12-2 to start 15a circuit

I use 14 ga. NMn on all my residential lighting circuits. Lighting only. It helps with conductor fill in switch boxes. Voltage drop is not usually an issue when you are dealing with lighting loads only. Especially incandescent. The less voltage you have the longer the life of the bulb.

Obey the rules and there are no problems.

 

[macmikeman]

Re: 12-2 to start 15a circuit

I'm with Flip on this one. Also I try to predict wattage of the the lights the customer will supply, or else I more or less overwire by running more home runs than normaly would in case we get handed a 900 watt halogen light fixture for the bath or some such.