hi, just wondering if anyone out there is using them. I got 3 of em' hanging vertically without hoods. I just extended the white and black wires that connect to the socket that the light came with. I used a long extension cord and cut it to the lengths I needed so the ballast stuff was outside the grow area. My grow space is 17 inches squared and 33 inches of hieght. Currently two clones I took from some good bagseed from my last grow. Sorry no pics. How would I get the lumens per square inch? I know some of you are very smart about these things. I'm not, please help. opinions are welcome.
saintgreen, You'll need ballasts to fire those HPS lamps. A ballast is a device that ignites the lamp through a capacitor and transformer so that it heats/warms up slowly. It is a "starter" for the lamp and you'll need one for each lamp. 70 watt ballast kit | eBay IMO, you're asking for trouble just hardwiring them. Welcome to GC. HTH chunk EDIT: Disregard above....missed the part about your ballast lol.
He said he kept the ballasts outside the grow area??? I have a 150W HPS flood I plan to use and keep the ballast remote.
You need the lumen output for a 70 watt HPS. Multiply that by 3, if that's how many of them you have. Divide that by the square feet of your grow area. This will give you lumens per square foot. Most people don't calculate lumens per square inch
You want lumens/sq ft. Square footage is 17 * 17 / 144 = 2. Lumens is 3 * 6300 = 18900 (HPS) or 3 * 5300 = 15900 (MH). So you either have 8450 lumens/sq ft (HPS) or 7950 lumens/sq ft. So next question is, what type of lamps are they, metal halide or high pressure sodium? If the former, you will need to find another light source to flower. I've been reading where some people seem to do pretty well with HPS for vegging then flowering, but not heard where MH will get you all the way through a grow.
Wow,thanks. Didn't think anyone would do the work for me. Right on, brother. The lights are hps. So do you think 8450 lumens per square foot is good?