I’ve added a 700 sf addition and I’m adding some new breakers to accomodate the addition lighting and outlet load.
Here’s my first question: How many lights can I safety power off of a single 15 amp breaker using 12/2 grounded wire? There will likely be four can lights, three or four standard two-bulb ceiling lights, and maybe a ceiling fan. Will splitting those across two breakers be adequate?
Second question: How may outlets can I safety power off of a single 20 amp circuit, using 10/2 grounded wire and outlets? These will be standard outlets in a bedroom, storage room and family room situation. No bathrooms involved, but my daughter might use her hair dryer in her room once and a while. That’s about the biggest load. I plan to have two 20 amp circuits to power these outlets. Is that sufficient?
Thanks for any help you can give.
Replies
Why are you using #12 on a 15 amp circuit and #10 on a 20 amp circuit? Do you have a long run?
For lighting circuits all up the max rated wattage of all of the fixtures on that circuit. Then you are limited to 80% of the circuit rating; 1440 watts for 15 amp circuits or 1920 on 20 amp circuits.
Unless those are bigger than typical fixtures that you mention they will all go on one circuit.
For general purpose receptacles in residential usage there is no limit on the number of recpetacles on a circuit. For commerical they use 180 watts (1.5) per receptacle.
If you have a big screen TV/home theater or computer center in the family room I would have it on a different circuit from the daughters bedroom.
However some local codes do limit the number receptacels a circuit.
Edited 6/24/2004 5:20 pm ET by Bill Hartmann
The former house did have a long run. That may be why he used 12/2 on lights and 10/2 on outlets. Since I've added a sub-panel, that shrinks the length of the run.
Should I use 14/2 on the lights and 12/2 on the outlets? Am I still okay using the 15 amp and 20 amp breakers, or should they be reduced as well? If so, to what?
And not to sound ignorant, but what's an Arc Fault Breaker?
Thanks for your help!
Arc fault circuit breaker: http://forums.taunton.com/tp-breaktime/messages?msg=33843.9
I'm not an el;ectrician use only 14 gague on 15 amp and 12 gague on 20 amp == if I owere you I'd only use 12 guague and 20 amp breakers -- there is soemthinin our code that the nuber of outlets/ights is 12 per circut -- I do not knwo who told you to use 10 gague
Unless you have a long run or have to derate for other reasons, which is not common in residential work, then the standard wire guage is #14 on 15 amp circuits and #12 on 20.
Some local codes require all circuit to be 20 amp and other limit lights to 15 amp circcuits.
And AFCI requirements also depend on which version of the code you area as adopted and if they have opted out of this.
BTW, if you are working under the 99 NEC then only the receptacles in the bedroom need to be protected by the GFCI.
However, if you are under the 2002 NEC then ALL outlets need to be protected. That includes lighting and smoke detectors.
But as I have said a number of areas have modified the AFCI requirements so you need to check locally.
If it's a bedroom, those outlets need an arc fault breaker.
Joe H