MPL
Member
Some basic info:
Ceramic Metal Halide lamps are currently not available in sizes over 400 watts. Philips is working on it, however there is no ETA.
The CMH lamps 150w and lower should work with digital ballasts.
250w and 400w CMH lamps will NOT work with ANY digital ballast EXCEPT the ones SPECIFICALLY made to fire CMH lamps.
250w and 400w CMH lamps will work with most good quality 250w (ANSI S50) and 400w (ANSI S51) HPS ballasts.
Read the second post in this thread.
This is the spectrum for a CMH bulb:
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The original first post follows:
Ok, so I have been reading around and found a few posts about these bulbs. I asked some questions but decided I really didn't want to hijack someone else's thread. Besides, I don't think CMH bulbs have a dedicated thread yet anyway.
So, I have found out that the Philips CMH bulbs have better spectrums than any other HID bulb on the market. I also learned a lot about lumens, PAR etc.
Everything sounds great so far, except I have no idea which ballast to use to fire the 250w and 400w CMH bulbs. Can anyone recommend a specific brand?
Also, the CMH bulbs are supposed to have strong UVB output. Does using an aircooled hood with glass in place reduce/remove this UVB? Is supplemental UV lighting recommended in this case? Would the Hydrotek Silverstar hood work well with the 400w? Any recommendations on a hood for this bulb?
How hot are the CMH bulbs? In a small grow, would the 400w require an aircooled hood to keep it close to the plants? I wanted to use it in a space about 2'x2'x5'H... maybe a bit larger, but not by much.
Sorry for the noob questions, but I'm getting my first grow planned out and just want to be sure I'm getting the most for my money, as I am far from rich.
Thanks!
Ceramic Metal Halide lamps are currently not available in sizes over 400 watts. Philips is working on it, however there is no ETA.
The CMH lamps 150w and lower should work with digital ballasts.
250w and 400w CMH lamps will NOT work with ANY digital ballast EXCEPT the ones SPECIFICALLY made to fire CMH lamps.
250w and 400w CMH lamps will work with most good quality 250w (ANSI S50) and 400w (ANSI S51) HPS ballasts.
Read the second post in this thread.
This is the spectrum for a CMH bulb:
Azeotrope said:Folks, I just recieved a very good and insightful PM in regards to "trouble" some folks are having with these lamps. It is not the lamp (99% of the time). These lamps were designed as a retrofit for industrial lighting fixtures that have a standard 3' ignitor. this means the ignitor was designed to strike/start a HPS (easy to start) up to 3' of wire away from the ignitor. Most of the off of the shelf Hydro shop ballasts are using just that and getting away with it. The less expensive ballasts use cheap components and switchables should be outlawed in my view. As the switchables go, they put a switch in the ignitor circuit. Most of those switches are not 5kv pulse rated or even 600v rated as they should be at a minimum. If you are going to use these bulbs you need to understand that they require (for best reliability) a high quality ballast kit (that will generally provide a high quality ignitor) ie. Advance, Venture, Sylvania, Sola(o.k.) and such with high quality STRANDED 600v rated 16ga - 14ga wire between the ignitor (ballast box) and the socket. You should also use 5kv pulse rated connectors and always ground your hood/reflector (safety). The only time in what is now many years of using these that I have had one fail, it was like 3 or 4yrs old and toasted by over use.
The HPS bulbs are easy to start and the CMH bulbs are harder to start. A weak or old ignitor, core or capacitor can be troublesome. Keep your cords to 6-8' if all the above is in order you should not have trouble. I love them so much I just bought 2 new 400w horiz at my supplier today for a re-lamp. $79.00 US! Can't beat that!!!
Good luck and keep after it.
-----------------------
The original first post follows:
Ok, so I have been reading around and found a few posts about these bulbs. I asked some questions but decided I really didn't want to hijack someone else's thread. Besides, I don't think CMH bulbs have a dedicated thread yet anyway.
So, I have found out that the Philips CMH bulbs have better spectrums than any other HID bulb on the market. I also learned a lot about lumens, PAR etc.
Everything sounds great so far, except I have no idea which ballast to use to fire the 250w and 400w CMH bulbs. Can anyone recommend a specific brand?
Also, the CMH bulbs are supposed to have strong UVB output. Does using an aircooled hood with glass in place reduce/remove this UVB? Is supplemental UV lighting recommended in this case? Would the Hydrotek Silverstar hood work well with the 400w? Any recommendations on a hood for this bulb?
How hot are the CMH bulbs? In a small grow, would the 400w require an aircooled hood to keep it close to the plants? I wanted to use it in a space about 2'x2'x5'H... maybe a bit larger, but not by much.
Sorry for the noob questions, but I'm getting my first grow planned out and just want to be sure I'm getting the most for my money, as I am far from rich.
Thanks!
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