Outlet wiring size

[TerryD]

I'm getting ready to start wiring some outlets in the garage. Does everyone agree that on a 20a 115V breaker, 12/2 w/ ground Romex is capable of carrying 4-5 outlets? The NEC says that 12AWG UF Romex not exceeding 3 conductors in a wire is good to 25A under 140*F. Voltage drop for the length of each branch is ~3%. I'm going to have two outlet circuits, one down each side of the garage off seperate beakers. Does this sound reasonable to everyone?

 

[bp71k5]

I'm getting ready to start wiring some outlets in the garage. Does everyone agree that on a 20a 115V breaker, 12/2 w/ ground Romex is capable of carrying 4-5 outlets? The NEC says that 12AWG UF Romex not exceeding 3 conductors in a wire is good to 25A under 140*F. Voltage drop for the length of each branch is ~3%. I'm going to have two outlet circuits, one down each side of the garage off seperate beakers. Does this sound reasonable to everyone?

Basic standard around here is that 20A breaker requires 12/2 and a 15A breaker requires 14/2 minimum. You can have as many outlets as you want, you just aren't supposed to load the entire circuit to any more than 80% capacity which would be 16A on a 20A branch. Just add up the amp draw for all the equipment you plan to run at the same time and plan your branches around that.


-Brian

 

[rick88blaze]

That's what I ran in my garage. At most I've got 4 outlets on one breaker. The only time I've had a breaker trip was when my compressor was running for about 30 minutes straight.

 

[76zimmer]

Basic standard around here is that 20A breaker requires 12/2 and a 15A breaker requires 14/2 minimum. You can have as many outlets as you want, you just aren't supposed to load the entire circuit to any more than 80% capacity which would be 16A on a 20A branch. Just add up the amp draw for all the equipment you plan to run at the same time and plan your branches around that.


-Brian

exactly!

Also a compressor should have a dedicated circuit, due to the possibility of extended use.

 

[TerryD]

Thanks guys! I thought that was right. As far as using more than one tool on a circuit, it's doubtful (but not completely out of the question) that will ever happen. When I get a compressor, it will have its own circuit as well as my welder and then the lighting will have one. I'm limited to 60A because that's whats feeding it from the panel in the house.

 

[79rustyk10]

That sounds fine to me.

 

[imiceman44]

Thanks guys! I thought that was right. As far as using more than one tool on a circuit, it's doubtful (but not completely out of the question) that will ever happen. When I get a compressor, it will have its own circuit as well as my welder and then the lighting will have one. I'm limited to 60A because that's whats feeding it from the panel in the house.

You do realize you can have a bit more than 60A total breakers on a 60A main, since you don't really load all of them up to 100% at the same time.
I don't know what the standard here is, but I have done up to twice my main in total breakers.

 

[TerryD]

Yeah, from memory I have about 130A worth of breakers in there right now.

1x 50A for welder circuit (pushing it with lights)
1x 20A for lighting (overkill, but the breaker was in there)
1x 20A for current outlets
2x 20A spares

The two spare 20A will probably be replaced with a single 20A 220V for a compressor as soon as budget allows.