Other than using good old common sense, is there a limit to the number of receptacles that can be wired to a residential 15 or 20 amp circuit? Also, is there a limit to the number of receptacles that can be put on the load side of a GFI receptacle?
There is no telling what people will be plugging into those receptacles unless you specifically ask them. I do residential work (new, old) all the time I never put more than 10 receptacles on any 15 amp branch circuit. I also prefer to not install any lighting on those ciruits. The lighter the circuit, the more you can add to it when the homeowner decides to add this and that. That's been my experience anyway.
Re: Receptacle question#100488 11/23/0611:02 AM11/23/0611:02 AM
as shock me said 10 on a 15 amp and 13 on a 20 amp circuit. this is the guide line for commerical where an outlet is rated at 180 va. its a good guide to use in residential. as shock also said lighting and power seperate, but i dont know how many residential sparkies follow this
Even though the exact wording of the NEC would allow for an infinite number of receptacles on a residential circuit, the mind recoils at the idea of an entire house on one circuit.
Or does it? It was once common for homes to have but two circuits ... one for all the lights, and one for all the receptacles. Of course, such homes were commonly like mine ... 400 sq. ft. on a 30 amp service. Our lives have changed quite a bit since then. That small house, even with changes made over the years, probably had less than 15 receptacles, total.
Now, let's look at a 'modern' home. I just put 110 receptacle in a single home. Seems a bit much for one circuit, doesn't it? Well, in an indirect manner, the code forces us to break that down into more than one circuit.
The bathrooms - 5 in this house - need to be GFI protected, and on a dedicated circuit. That takes maybe 8 receps off the "big" circuit.
The kitchen needs two dedicated circuits ... that removes another 12.
Furnace is a dedicated circuit (2). Laundry (3). Garage (6). Sump pumps (2). Specific appliances (10). That's 23 removed form the total.
Code calles for the bedrooms to be AFCI protected. While yuo could place the entire house on one AFCI breaker, the requirement strongly encourages you to place each bedroom area on it's own circuit. It's just easier that way. There's another 40.
Just looking at this rough breakdown, we've pruned the number of general use receptacles from 110, down to 25.
That's just the roughest of breakdown. In reality, this house was wired by a chaep-as-sin "tract hack" (not I), who missed no opportunity to cut corners .... and I doubt there is any circuit with more than 9 receptacles on it.
We sometimes forget that the NEC is but one of many factors that govern our work. As the NEC itself says, it is NOT a design manual. "Code compliant" and "good design" are completely different matters.
The real limit is the 3va per square foot rule. If your house is less than 800 sq/ft you probably could put them all on a 20a AFCI. You would still have 4 more 20s for required receptacles in bath, kitchen and laundry. The absolute number of receptacles is not that important, just the load.
Re: Receptacle question#100491 11/24/0610:45 AM11/24/0610:45 AM
In order for a manufacturers instructions to be binding they have to be included with the listing or labeling. Every manufacturer tells you no to use anyone else's breakers in their panels but since that instruction is not on the label that bears the listing mark you can still use UR recognized breakers in those panels.
"This alternating current stuff is just a fad. It is much too dangerous for general use" Thomas Alva Edison