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)?
Electrical code question for 240v lights.
- Thread starter Twerkle
- Start date
ALong14U
Well-Known Member
I'm not 100 percent as it might depend where you live. But I think your safe. As I know you can do the same with 120 in most cases.
_eNVy_
Member
i used to be an electrician. How long a run of wire did you pull? From main breaker to whatever receptacle you're going to use? If it's over 100ft you'll probably be wise to step up the wire gauge. is the 30amp breaker a single or double pole? If it's a 2 pole breaker you could run two dedicated circuits off of it to 20amp receptacles using 12/2 wire that's what I would do. Again if the run is a long one you'll have to step up to 10awg
_eNVy_
Member
Also save some money and use gfci receptacles and ditch the gfci breaker for a basic single 2 pole. You can daisy chain off the gfci recepticle to other ones and they'll all be protected.
Edit: I completely neglected your 220/240v lights. Sorry about that! you can't run 220/240v to a 15/20amp receptical! You'll either fry whatever gets plugged into it or melt the receptical itself. Fire hazard for sure. You can however do as I originally recommended which is using a 2pole 30amp breaker and running a circuit off of each. This would give you (2) 110/120v dedicated circuits. Each to its own 20a gfci. You can then from there branch out to more 20a receptacles. Your 240v ballast should be able to regulate both 110/120v and 220/240v. check the UL listing on the ballast it will give you all the info you need.
Edit: I completely neglected your 220/240v lights. Sorry about that! you can't run 220/240v to a 15/20amp receptical! You'll either fry whatever gets plugged into it or melt the receptical itself. Fire hazard for sure. You can however do as I originally recommended which is using a 2pole 30amp breaker and running a circuit off of each. This would give you (2) 110/120v dedicated circuits. Each to its own 20a gfci. You can then from there branch out to more 20a receptacles. Your 240v ballast should be able to regulate both 110/120v and 220/240v. check the UL listing on the ballast it will give you all the info you need.
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OldMedUser
Well-Known Member
I just unwound some barbed wire ad screwed it on to the bars in that power box thngy and made sure they don'y lay in the mud on the floor and nuthin caught fire yet.
The sparks scare the kitties out of the grow room so it's all good hear. N-yuk yuk.
I think -eNVy- knows better than me.
The sparks scare the kitties out of the grow room so it's all good hear. N-yuk yuk.
I think -eNVy- knows better than me.
frozendude
Member
I believe there is an NEC code rule that specifies that devices must have a minimum rating for the circuit they are installed on, which means any receptacles installed on your 30A circuit much be rated for 30 amps (We have that rule in Canada, pretty sure I've seen that NEC rule on electrician forums).
Found it, NEC 210.21
What ALong14U might be referring to is a situation where normal 15A receptacles are installed on a 20A circuit. This is allowed because 15A receptacles are actually rated for 20 amps, it's just the configuration that makes it a 15A receptacle.
Although not really unsafe (in my opinion), its unfortunately still not up to code.
And no, you won't fry anything running 240V (under normal circumstances), Envy is answering a different question that he made up.
Found it, NEC 210.21
What ALong14U might be referring to is a situation where normal 15A receptacles are installed on a 20A circuit. This is allowed because 15A receptacles are actually rated for 20 amps, it's just the configuration that makes it a 15A receptacle.
Although not really unsafe (in my opinion), its unfortunately still not up to code.
And no, you won't fry anything running 240V (under normal circumstances), Envy is answering a different question that he made up.
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Colanoscopy
Well-Known Member
240v 13amp for UK house circuits. Usually protected by an rcd. Don't bypass any rcd cos it will likely save your life. You can safely run about 4000w from a socket (UK) without tripping anything
Jman electrician in Canada,
First, you only want to load your circuit to 80%, especially with a gfi, they are designed to trip more frequently, so first make sure that your 4 lights aren't pushing anything over 24 amps, which I doubt. I'd probably run two lights off each breaker and into a 4x4 junction box, and then just jump out to each light from there with bx cable,#10 should do.
First, you only want to load your circuit to 80%, especially with a gfi, they are designed to trip more frequently, so first make sure that your 4 lights aren't pushing anything over 24 amps, which I doubt. I'd probably run two lights off each breaker and into a 4x4 junction box, and then just jump out to each light from there with bx cable,#10 should do.
Oh also, if the inspector is going to consider the location a "wet" location, which I'm assuming is the case since your using a gfi beaker, you'll want to use liquid tight flex as oppose to the bx once you get into the wet room (hollow flexable tube with thick rubber on the outside). You'll also need liquid tight connectors as well. Just head over to an electrical wholesalers and tell them what your plan is and they will hook you up. Avoid lows and home depot, they don't know shit about code and materials are cheaper from the wholesalers as well. Hopefully that helped you out a bit
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_eNVy_
Member
Was pretty lit when I edited my Reply.. lol! I sure did make up my own question though
.
sonson176
Well-Known Member
In most cases, such as this one, tapping 240v branch circuits to feed 120v outlets is not permitted. Even in the rare scenarios where it is permitted, most inspectors you'll encounter wont like it anyway. Don't put anything other than 240v 30a rated receptacles/plugs/equipment on this circuit and you'll be fine. Do you have a current copy of the NEC?
Olive Drab Green
Well-Known Member
Isn't 240v a European standard? I thought 120v was US standard? Of course, I may have been given the wrong impression.
Aeroknow
Well-Known Member
Most power companies in the US supply 240v power. 240v is basically 2-120v circuits
Justin-case
Well-Known Member
No you weren't. Stfu before you get some one hurt.
Olive Drab Green
Well-Known Member
Appreciated.Most power companies in the US supply 240v power. 240v is basically 2-120v circuits
Justin-case
Well-Known Member
Rule of thumb, voltage( 240) divided by Watts ( 4000) equals 16.6666amps. Meaning a 20 amp double pull 240 volt breaker will work. But like areo says you need to place a sub panel near your room. I always recommend hiring an electrician, you'll get a better job and you can sleep at night, well worth the money.
Justin-case
Well-Known Member
I think Europe is like 150v
Justin-case
Well-Known Member
Run your lights on 240v they will run much cooler prolonging the life of your equipment.
If you run a 120v thirty amp circuit you'll need to use ten gauge wire, and you'll only get two thousand Watts on a thirty amp 120v circuit. 4000 Watts ÷ 120v = 33.3 amps
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_eNVy_
Member
How do you figure? 30a 2pole breaker - each pole of the breaker would be 120v passes inspection where I live. I'm not saying run (2) 240v circuits off a single 30a breaker! So don't be an asshole