Electrical question 240v

Hey guys, I'm currently running 2 magnetic ballast with 2 1000w hps bulbs, each on their own 15amp breaker, as they are rated to run something like 9.6amps on 120v. Now I'm thinking of adding 2 more 1000waters, but I'd like to run it on a 30-40amp breaker (dont remember which it is) and have a Female outlet already wired ouf of the box to run a 240v heater for the garage (which I never use).

The Ballast itself, has a outlet of 240v, just have to plug it in and flip the switch.

I'm comfortable with playing with electricity, I'm a safe guy and always pretty conservative in my ways of playing with electricity. Question I was asking myself was, If I would like to either, find a dryer male outlet, plug it in, run the wire into my room to a 3 pin standard inlet (like normal 120v) would that be the safest procedure?

I had a crooked electrician last week in the area and he fucked off before calling me and didn't pass at my house like he was suppose to. So I said fuck it let me try that out.

The ballast itself, like I said, as an outlet, shapped like a computer powersupply plug, blocked by a red tape written 240v on it, I'm presuming that I use the same CORD, and plug it into a normal 120v inlet.

Can anyone shed a little bit of light on the matter for me?

Thanks

Ok let's look at a 1000w ballast on 240v system. To find the amperage, we say 1000/240=4.2amps. With two of these it would equal 8.4 amps total. You don't want this on a 30-40 amp breaker. If something happens within one of the ballast, it could catch on fire before the breaker trips. What I would do is to run a dedicated circuit on a double pull breaker using #14 THHN copper(standard house wire) this is good up to 15 amps. I would also look online and purchase the actual 240 volt plug for the ballast. This will have a different configuration plug which is a safety feature so that it cannot be plugged into a 110 volt circuit. You can use your existing 240 volt circuit and just change the breaker to a 15 amp if you prefer. The larger wiring will be no problem. You will just have to pull the wire from you existing outlet and set a second outlet for the second light. I hope this helps and if you have any questions, just let me know.

This raises many questions to readers. Assuming you are using the four 1000 watts hps lights for flowering in the same room, how are you controlling the lighting cycle (12 hours on, 12 hours off) to each light? Generally most growers prefer to use one lighting controller to control four 1000w lights. Lighting controller use a relay (also called a contactor) capable of high power switching, triggered by one timer that is drawing less than 1 amp of current to operate the relay. Assuming that all four ballasts can be converted to run on 240 volts, the 30 amp double pole breaker circuit would be ideal for a 4 lights lighting controller. Is your grow room in the garage or in a separate room that share an adjacent wall to the garage? Would it be easier to run 10-2/with ground NM-B (romex) cable from the grow room to the 30 amp double pole breaker or would it be easier to tap into the existing 30 amp circuit using a junction box?

Dt1970 said:

Ok let's look at a 1000w ballast on 240v system. To find the amperage, we say 1000/240=4.2amps. With two of these it would equal 8.4 amps total. You don't want this on a 30-40 amp breaker. If something happens within one of the ballast, it could catch on fire before the breaker trips. What I would do is to run a dedicated circuit on a double pull breaker using #14 THHN copper(standard house wire) this is good up to 15 amps. I would also look online and purchase the actual 240 volt plug for the ballast. This will have a different configuration plug which is a safety feature so that it cannot be plugged into a 110 volt circuit. You can use your existing 240 volt circuit and just change the breaker to a 15 amp if you prefer. The larger wiring will be no problem. You will just have to pull the wire from you existing outlet and set a second outlet for the second light. I hope this helps and if you have any questions, just let me know.

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Some ballasts include supplementary equipment protection, in which case you can leave the 30-40 amp circuit breaker alone. Circuit breakers at the panel are meant to protect the branch circuits, they handle fault conditions. If your ballast really takes a shit dive, and shorts out, the 30-40 amp breaker is still going to trip. The branch circuits in your home are rated 15, or 20 amps depending on their location, and the equipment they are protecting. Go into your kitchen, and plug in an electric can opener... is it drawing 15 amps? Not even close... does that mean its not protected? No.. if a short circuit occurs the amperage drawn through the circuit conductors will be more than enough to protect the equipment and the conductors. Likewise, as long as the conductors running to your outlet are rated for the 30-40 amps, i wouldn't worry about running a single ballast because of the significant difference in operating vs protection.

Under a real failure of the equipment your most concerned about the conductors behind the wall where a fire can start. The equipment has failed, its toast anyway, it needs no more protection. Its not a motor load, its not going to overload at 200, or 300% of rated current, its just going to fail. Theres a reason motor loads have their own code in the NEC, they present an entirely different set of protection needs.

Interesting point made by Total.Hydroponic.Control. I often did wonder, considering that most ballast power cords uses 16 awg wires, how those store bought lighting controllers can get by using 30 or 40 amps supply cords without over current protection inside the controller to the controller's outlets. None to my knowledge are UL listed and only a few are ETL listed. Not of any real concern to myself because I make my own lighting controller.

The national fire protection agency, along with the national electric code governs the branch conductors, they do not care, and have absolutely no governance, over the equipment we plug into them. Go look at a hair dryer... its 18 gauge wire pulling 1800 watts...

In reality what you have to worry about is that your wire size is correctly sized with your overload protection. NEC section 310.16 will give you the amperage that any type of wiring can handle. If you want to use a 20-30 Amp breaker, just make sure that you are using at least #12 THHN (and I quote THHN because this is the most common in household use) with a ground. The overload is mainly to protect the wiring from catching on fire.

Stop the nonsense, good ideas are thrown at you, however, a simple solution is this...


Take your 30/40 amp outlet which ever it is, it does not matter….make sure breaker is either …

Make sure wire size is #10 awg…if it’s a 30 amp… [easy enough]

Or make sure it’s 8 awg or larger if it’s a 40 amp…


Now, turn breaker off, and put a piece of tape over it so it won’t get turned on by accident while you are working on it….


Go to Lowes/Home Depot and buy yourself a “Sub Panel” buy one that has breakers already in it…

[I bought one recently for $55.00 that had 6-20 amp breakers, and a 100 amp main, and a spare 30 amp]

It will say on the box 100 amp sub panel or something, it means bus is rated at 100 amps…


Now take your outlet 30/40 amp off wall... un hook all wires


Now take your new sub panel and mount over the old outlet…

[ wires should be Black/Red/White/Green or copper]


Hook black/red wires to 30 amp 220 vac breaker, and snap it into place on panel…if you have #8awg wire at outlet, you could buy another 40 amp breaker and make your panel a 40 amp sub…

Hook green and white to ground and neutral terminal blocks


You now have a 30 amp sub panel…[or 40 amp if you have bigger wire]


Now run your 120/20 amp circuits with 12 awg, or add 15amp circuits with 14 awg wire…


220/15 amp breakers will need to be bought if you are going to run 1000 watt lights on 220 vac…


Run separate circuit for each light, you now are set…


It’s easier than you think, and the way to do it right….


Good Luck!