Lumatek 400w purple dimmable ballast and cmh

I recently upgraded to a 400w lumatek dimmable ballast and I am having a heat problem. I have heard rumors that these new ballasts will run a CMH ceramic metal halide lamp. Is this true? Can anyone confirm this for me before I buy one? I have been searching online and I have read conflicting stories. And for those of you running cmh, is it really that much cooler than a hps bulb? Thanks.

I will chalk this one up as a myth for Mythbusters. Does anyone use the cmh bulbs at all? Is a CMH bulb much cooler than an hps? I may just find a used magnetic ballast to use for the summer til it cools off enough. I can use one of my 250 bulbs with my ballast but i would rather run a 400 because they are hella bright compared to the 250. Anyways.... bump

I heard they have problems with the eye Hortilux, I don't think you can run CMH's in them but you could always ask your local grow shop or call/email Lumatek.
For vegging, I would recommend an Agrosun 400w MH (7200k spectrum).

There are rumors abound on Lumatek's not working with Hortilux bulbs. I emailed Hortilux and Lumatek support directly to ask them about this. Hortilux never responded. Lumatek said they have heard about the problems from reading the forums, but haven't seen the problems themselves first hand when testing, as during testing everything works fine for them (so they say). I also have ordered and am awaiting 6 Lumatek dimmable e-ballasts (400w) with Hortilux 400w mH and HPS bulbs so I was very concerned about this also..

From what I've read and found it seems to be more of a problem with the older generation lumatek ballasts and isn't as problematic on the newest revision (the ballasts with the dimmable 400w, 600w, 1000w, etc. switch...the one thats actually labeled with wattages and not the older revisions that have something else labeled on the switches.) Also from what I've been told this is much more of a problem on the 600w ballasts as 600w is a NON STANDARD electrical wattage. If you use the 400w ballasts you'll probably be fine. I'll post back in a year after I use mine for a year and let you know how it worked out!

The problem related to the amount of voltage the lumatek ballasts were using to start up (the initial firing) the Hortilux bulbs. Apparently Hortilux bulbs are different and use a non-standard amount of initial voltage. Lumatek originally had problems with this, but claim this is now fixed. Given they are truly digital ballasts with programmable CPU's once they identified the problem it wouldn't have been that hard to actually fix it. They just reprogram the ballast to use a lower voltage on lamp startup if its dettected as a Hortilux lamp.


Hope this helps,

X

Thanks for the response guys. I just turned it down and put in my 250 agrosun. Heat is fine now just not as bright. I am either gonna wait til after the summer to use the 400w or rig up something so my portable ac blows directly into my tent. With the 400w it was getting up to 85 degrees in there even with the air cooled hood. 400 puts out some heat.

um... 85 degrees is okay to grow in long as you have air flow...

Even with the 250 it is still at 82 degrees. heh I guess I will just use the 400 because it is hella bright compared to the 250. But just an fyi, the 250 with my lumatek is much brighter than it was in my magnetic ballast. I like the lumatek.