Electrical code question for 240v lights.

Twerkle said:

I'm about to start constructing my grow room in my house. Our house is currently being remodeled and the room needs to be up to code because inspectors will be in and out over the next few months. I'm going to be running 4-1k lights off a 30AMP GFCI. My question is; when I run the supply line to the receptacle can I use 15/20amp outlets chained lineally as long as the wire is the correct gauge for the 30amp breaker. Or can you only run outlets rated for the branch circuit breaker (30)?

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The problem that I foresee you may run into with an electrical inspector would be Article 210.6 of the NEC code. Luminaires exceeding 120 volts nominal are not permitted in dwelling units. Perhaps you should wait until after your house remodeling is done to start your grow room construction for 240 volts lighting, or else choose a building structure that is not attached to the house such as a shop or garage.

Mogul base lights, along with other listed electric discharge lights are permitted to exceed the 120 volt limit up to and not above 277v. This is in 210.6(c) 1-6. It does conflict with itself, but the 120v limit is usually specified for dwelling units. I would argue that it's a special purpose area separate from the dwelling unit itself. Use 5/8 fire rated Sheetrock and rated doors to prove it to them if need be.

Make sure there's no local codes against it first, I doubt there will be. Get in touch with the AHJ in your area if you can.

Olive Drab Green said:

Isn't 240v a European standard? I thought 120v was US standard? Of course, I may have been given the wrong impression.

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Europeans use 230volts 50Hz electrical circuits that comprise of one ungrounded current-carrying conductor and one grounded current-carrying conductor, thus would use single-pole circuit breakers for their circuit breakers. The vast majority of residents living in North America are supplied with a 120/240 volts split-phase 60Hz electrical service. Although we use a grounded conductor (neutral) as one of the current-carrying conductor in our 120 volts circuits, we do not use a grounded conductor as a current-carrying conductor in our 240 volts circuits. Therefore we are required to use double-pole circuit breakers for the circuit breakers in our 240 volts circuits, while single-pole circuit breakers are used in our 120 volts circuits. Both European and North American uses a grounded (the normally noncurrent-carrying) conductor for the safety ground.