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	Subject - Adding service off of an existing outlet. USWC24 I am looking to add 3 110V outlets to an unfinished basement. I will be pulling power from an existing outlet. The breaker shows 15amp service. I would like to know if adding these outlets will pose any issues ie. safety issues, or not enough power. This will be for an art studio runnng 2 computers/monitors and a light table. Any info would be great. Scott Vickrey Is there currently is a receptacle in the basement? If so, when you kill the power to the receptacle at the panel what else looses power? USWC24 Yes there is an existing outlet. The existing outlet is powering my security sys, water treatment equipment, and computer network (router and telephone). The outlet was dedicated for the security system by the builder and nothing else turns off when I shut off the power. JimmyDee You will be alright by adding to the existing circuit. Remember that in an unfinished basement, a ground fault circuit interrupter receptacle is required by the National Electric Code. Jim Electricman The rule of thumb for most electricians is you can have 8 general purpose outlets on a 15 amp circuit. This is usually calculated in this manner 120 volts x 15 amps = 1800 watts 1800watts x 80% = 1440 watts Since Nec stipulates each duplex outlet to be rated at 180 watts and you should only use 80% of the total branch circuit 8 X 180 =1440 watts. So 4 outlets would only be calculated at 720 watts only half of what is available for general purpose outlets. David Hyatt That is a great way to do it Electricman, wish most contractors thought ahead more and not just saving money. David Hyatt Electricman, In a residence, the code will allow 100 recept. on a circuit, I say a hundred because there is no limit for general purpose recpts. on a branch circuit. The 180va for each unknown recept. applies to commercial buildings. They want to encourage as many as possible to keep from having drop cords. Also the 80% rule will only apply a single piece of equipment cord and plug connected, or continuos load such as florescent lighting. Recepts. can be loaded to 100% of the branch circuit rating because recpts are not considered continuous. Now for the question at hand, you should be fine as Jim stated but if it is accessible to add another circuit for the computer I would. This will prevent feed back and power spikes to the computer. Most computer manufactors require a 20amp dedicated circuit for warranty purposes. P.S. My computer is on with half the lights in the house. Electricman David, I new my conservitive calculations would get a comment from you guys I realize the code allows for 100% of the circuit can be used in residential wiring. That being said I still calculate most of my circuits keeping them as close to the 80% as possible. Just trying to give that extra safety cushion thats all. Thanks