Hey everyone! I'm designing my cabinet and have settled on using 2 150w HPS in the flower section. How hot do the 150's get? I've seen pics of people who have their plants 4" from the bare bulb with no leaf burn happening (and without a cooltube either!) Do you really need a cooltube on a 150w, or if the flower chamber is ventilated well enough can you go without one? I would rather go without and save the 10% of luminocity you lose sending the light through the glass before getting to the plant. Thanks!
150w lamps are pretty cool compared to higher wattage, if you have an exhaust right next to the light or a fan blowing the heat off the lamps you won't have a problem if the plants get fairly close to the bulbs.
yes like all HID's they put out a good amount of heat, but with a good ventilation system you won't have any problems really. I'd say keep them 6-8" away.
Are sure you've got your heart set on 150W HPS? Each unit actually draws almost 200Watts from your wall once you include the transformer loss, but puts out only about 15,000 lumens. That means you'll burn about 400 watts of power from your wall socket, and get 30,000 lumens. A 250W HPS on the other hand draws about 300W of actual power and puts out 29,000 lumens. That means you'll save 100 watts on the electric bill and only sacrifice a small ammount of light in return... Your call, check the link in my sig for more info...