Ok quick lighting question, if one is to setup a "400w" light of any kind(mh,hps), wouldnt you need a higher volt recipticle installed in your house. Just curious, and what is the average, 125V? I know a little bit about electricity, Its not free and it can blow you up. And also what would running this cost you a month?
OK There are two voltages you could work at: 120 (110, 125 are close enough to the same thing) or 240 (could also be 210, 220, etc.). I will assume you are using standard US house current, so I'll go with 120V. You need to buy a light with a ballast that is intended for 120V. Allow an extra 10% energy usage (rough figure) for heat loss at the ballast. That means the 400W fixture will use about 440W (the bulb is 400W, not the entire setup). W=A*V, so to figure amps, A=W/V At 120V, that means A=440/120=3.67 amps. Any modern breaker will handle this just fine as long as there isn't a bunch of other items on that circuit. As far as energy cost per month, that varies depending on your local prices. Check your utility company's web site as they probably have the rates posted. Assuming .10/kWh and a non-tiered rate schedule, you would be paying 10 cents for every 1000 watts used per hour. If this is a bloom light, it will be on 12/12 every day. I'll work it out for a 30 day month: 12 hours * 30 days = 360 hours use 360 hours * .44 kW (light) = 158.4 kWh 158.4 kWh * $.10/kWh = $15.84 electricity used that month. Of course, you will probably have to substitute values that are accurate for your situation, but that is the math you need to do. You can buy a 220V light fixture and bring 220V power to your grow for it, but that may require doing some (re)wiring, and is best left to an electrician. Have fun!
yea i hear that, ive just been reading these people using "transformers" for their lights and wandering what all that is about? I guess thats whats going on... (higher rated lights) But as far as ordering a 400w say Mh light rated at 120v, all you need is a bloody end of an extension cord rated for 120v, wired to your light?
Also been reading about people using CFLs for early stages. Whats the benefits for that? Lights closer to the plants / The spectrum of light compared to a HPS/ less expensive? I really should read up on lighting but im really lazy and rather get a quick run down.
I think the transformers you are referring to are actually ballasts. A ballast is responsible for upping the voltage and the frequency (I think I got that right, too high to look it up) so that the bulb will burn correctly. Plus they will provide a pulse of power that caters to a specific wattage and type of bulb. You would need a ballast for a MH bulb of your chosen wattage with a 120V pigtail and the wire to the bulb socket. The socket will come with the ballast, or may not. You need one. You will also need a matching bulb. Nothing else will work right. You will need a hood or a reflector. A good hood with glass can be air cooled to remove much of the bulb's heat. Don't use an extension, or if you do it better be beefy enough to stand erect on it's own, because that much draw thru a normal cord will burn your house down in a most unsatisfying way. An electrician would know best, but if you make a cord out of industrial ends and ROMEX of a good size, you'll be OK. Except that the light may not work or may fail prematurely. I dunno. I don't even use 120V, let alone use an extension. I simply wired the space properly for 240V. :shrug: CFLs are compact fluorescent lights. They are cheap, easy, fairly safe, and don't make much heat. They will work OK if they are the right spectrum, but should probably not be used in bloom if you want big yields. Not enough lumens. OK for veg tho. Just keep them a couple inches from the plants - the more the merrier. If it's a small grow, these might be the ticket for veg. Use HPS for bloom. Surprise! New ballast. MH and HPS can be used with a single ballast only as an expensive upgrade, or if you go digital, which is a whole 'nother story.
well i was just looking for a 400w hps/ probably. basically just wanted to know if itd run on a house circuit the 120v, succesfully. and id be using whatever reflector it came with it'll be ordered like a 400w floodlight so it should have a reflector built in. just wanted to know if itll run on 20amps. or would i need a 240 outlet. im not looking to take apart the light either to seperate the balast from it. if you go to econolight and check out the 400w hps floods, is kinda what im going for. if you want to check them out.
