Power requirements - need advice!

@dbrn32 I’m going to do some new wiring for the space where I can put a couple grow tents. I can install the wiring but I need some advice on what I’ll need, in terms of capacity and lines. Let’s say I, eventually want to have 1 5x5, 1 6x6 and one 2x4 tent in a room. Plus capacity to run fans, maybe a hydro system, etc. What would you run in there if you were wiring it new? I mean, would you run 2 independent lines 110v on 30A breakers to, say, 4-way outlets? Or is that less than I need or more than I need? Could I get away with Romex 12-2 wire?

Luckily I have a panel nearby that’s easy to access and that has plenty of free slots available. Might as well over-wire than have to upgrade later. Lol. I’ll probably never go that large, but it isn’t going to cost much more material-wise to go overboard and the work involved is the same, either way.

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Depends on what you plan on using or lights? I’m guessing you’ll need something like an independent 20a just for the 5x5 lights.

Is light schedule going to be the same in any of them?

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@dbrn32 Tents (in a perfect world scenario) would be on their own lighting schedules. Like a veg tent, a flower ten and a seedling starter tent. All LED or T5 Flourescent fixtures. I’m getting a HLG 600H for the 5x5 after you and I discussed in a separate thread. What about 3 different outlets on 3 different circuits, each 30a breakers. Wired with 12-2. Lights for bigger tents get their own circuit. 3rd circuit just for fans and other peripherals?

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A single 20a good for hlg-600, you could probably sneak a circulation fan or two on that circuit too, but you’ll probably have a problem trying to start any bigger loads on that circuit.

Figure on another 20amp circuit you could probably run extraction fans for all 3 tents and a light for 2x4.

Where I believe you’ll run into problems is with a 6x6. Which kind of why I was asking about light schedules. You could run something like a 230 30 amp circuit that would allow you to run two big lights or 4 smaller lights. But having two big spaces is going to pull a lot of power.

Ok. I’m following you. Then, I’ll make it easy, forget the 6x6. I’ll stick with 5x5 tents, then. I’ll run 3 separate 20a circuits, each to a 4-way outlet. That ought to provide plenty of scalability for a while and overkill for the foreseeable future. .

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That should fly. In most circumstances 12/2 with ground is good for 20a circuit. You should probably consult local code addendums before buying anything though, or someone in your area that would know. Here Romex is fine as long as it’s covered by finished walls. But that can vary some based on location. I don’t do a lot of residential work, so not as familiar with requirements.

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Most lights that I’ve seen that were decent at best run on 120v and no more than 20a

I’m guessing anything above 240v and 50a will be good for you if you’re trying to run a big light or two with some fans

@dbrn32 You said “code!” Lol! There’s no code where I live. Lol. Way too middle of nowhere. I think a code violation is the least of my worries. :wink::flushed:

Well that’s on you lol.

You would be good with 2-20 amp circuits one for light and 1 for fans and other items

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Thanks fellas! Got an electrician buddy that’s gonna help me some too. Just don’t want to explain what I’m doing it for. Lol


I’m also a electrician so if you have any questions :wink:

If you can get the help here why invite a friend whom you don’t want to know what you are doing to your space. He’s going to have a inquiring mind and before all said as done you’ll tell him what it’s for. But there’s nothing like in person instructions either. But hope you get it figured out

One thing to think about: Are you going to be running an air conditioner, or doesn’t it ever get warm enough. AC takes a lot of power. Even for a one room window unit, I would run a 15 amp circuit and breaker.

I don’t know if Mean Well has a slow-start feature. That lowers the inrush current when a driver starts up. If not, you could always use different timers to run each driver, so they don’t all startup together.

You should dedicate a 20 amp service for the tents and have a second 20 amp dedicated service to run your ac ,dehumidifier and any other high draw appliances ie electric heater
I ran teo 4x4x7 tent with 4 led fixtures in each plus fans on a 20 amp circuit with no issue
But powered up all other equipment on a second
As discribed

If you use a 20 amp breaker, you should also use 20 AMP receptacles. Standard ones are only 15 AMPs and you could possible draw 20 AMPs from one outlet. That would not be good. They are a few dollars each.


Thanks again, fellas! My buddy is a smoker also and he’s just helping me run into the panel. He thinks we’re doing a remodel in the space and rarely comes over; no reason for him ever to see where the grow room is. Besides, I actually have 100% confidence in him - I could even tell him what I’m doing and he’d help. But I don’t have any reason to, so I’m not. I appreciate the concern.

@1BigFella Thank you for the heads-up on those receptacles! I’ll do that.

As for AC. The space is really well insulated and it’s climate controlled already and stays around 72°F. There’s even a duct where I could tap into to draw AC from the building, when necessary in the summer. There aren’t any windows to put a AC unit so, if ones required I’ll have to get a stand up unit. But, it’s always good to prepare. So, I’ll have 3 different lines run in there to use. 1 for lights, one for AC and 1 for peripherals. That ought to get me started anyway.


I want to build an electrical board for all my lights,fans,filters ect. Something simple but safe! I am very familiar with wiring just looking for ideas from those of you who have built them so I don’t have to “REINVENT” the “wheel” so to speak. Set up will need 3x 2 way recepticles or 2x one 4 way. One 4 way will be on a timer the rest will be " switched". Like I said I have a design in my head but would like to see yours before I start so I might solve future issues (I don’t know about yet) before they arise. Thanks, picts would be greatly appreciated. Any suggestion’s as well.

As long as you use 15 amp circuits, you can just plug a standard power strip into a standard outlet. That gives you 6 or more outlets you can plug things into. Most timers are also 15 amp, so they work fine. You may need two timers, so you can have one for a veg chamber and one for flower.

With a dedicated 15 amp circuit, you can use about 1800 true watts, which is a honking big light(s). That’s big enough for at least 36 square feet. If you need more, you might consider just running two dedicated 15 amp lines from your breaker box. 20 amp lines are possible but 20 amp outlets are expensive, and I’ve never seen a 20 amp power strip.

Obviously, if you plan to run a room-size AC you will need a dedicated line for that. You probably can’t run a light and an AC unit on the same line. Fans are pretty inconsequential because they don’t use much power.

Who is @dbrn42? Just kidding.