jar546
Forum Coordinator
How many receptacles can you have on a circuit? That is a question that you hear every now and then and there is an answer, and that answer is: it depends.
The first thing you need to know is whether or not the application is for commercial purposes or for a dwelling unit because there is a big difference.
In a dwelling unit, such as a single family residence there is no limit. You can actually put as many receptacles on a circuit as you like. Of course you should be reasonable about that but the code does not limit you. There are some requirements for laundry, kitchen countertops, bathrooms, etc. for load calcs but I am talking general use receptacles in a home. When I stated "should be reasonable," remember that general use receptacles are normally part of the lighting circuits when you figure the 3VA per square foot. The bottom line is that in residential, there is no limit to the number of receptacles on a branch circuit.
Commercial, however, is another story. With commercial work, per 220.14(I), you must figure the receptacle load at 180VA per single or duplex receptacle on one yoke. Of course, if you are going to have dedicated equipment, that is another story. But for general use receptacles such as an office, it is going to be 180VA per yoke whether it is a duplex or single. Let's figure it from this example:
Each yoke is valued at 180VA and these will be for 120V circuits. Using Ohm's Law we divide the VA(180) by the Volts (120) and get 1.5A per yoke. On a 15A circuit we would divide the 15A by the 1.5 per yoke and we get exactly 10 receptacles. Easy, right?
For a 20A circuit we divide the 1.5A per yoke into the 20A and get 13.33. Since we can't have partial receptacles, we round back to 13 which is the maximum number of receptacles allowed on a 20A circuit for a commercial application.
As always, as stated previously, if you have dedicated equipment on a circuit then that would limit the number of receptacles as you have a set load.
During commercial plan review it is rare that I see a design with more than 9-10 receptacles on a 20A circuit.
The first thing you need to know is whether or not the application is for commercial purposes or for a dwelling unit because there is a big difference.
In a dwelling unit, such as a single family residence there is no limit. You can actually put as many receptacles on a circuit as you like. Of course you should be reasonable about that but the code does not limit you. There are some requirements for laundry, kitchen countertops, bathrooms, etc. for load calcs but I am talking general use receptacles in a home. When I stated "should be reasonable," remember that general use receptacles are normally part of the lighting circuits when you figure the 3VA per square foot. The bottom line is that in residential, there is no limit to the number of receptacles on a branch circuit.
Commercial, however, is another story. With commercial work, per 220.14(I), you must figure the receptacle load at 180VA per single or duplex receptacle on one yoke. Of course, if you are going to have dedicated equipment, that is another story. But for general use receptacles such as an office, it is going to be 180VA per yoke whether it is a duplex or single. Let's figure it from this example:
Each yoke is valued at 180VA and these will be for 120V circuits. Using Ohm's Law we divide the VA(180) by the Volts (120) and get 1.5A per yoke. On a 15A circuit we would divide the 15A by the 1.5 per yoke and we get exactly 10 receptacles. Easy, right?
For a 20A circuit we divide the 1.5A per yoke into the 20A and get 13.33. Since we can't have partial receptacles, we round back to 13 which is the maximum number of receptacles allowed on a 20A circuit for a commercial application.
As always, as stated previously, if you have dedicated equipment on a circuit then that would limit the number of receptacles as you have a set load.
During commercial plan review it is rare that I see a design with more than 9-10 receptacles on a 20A circuit.
