-What ventilation setup works to have sufficient cooling for a 400Watt MH setup? Is difference in heat output really that much higher than with 250W MH?
-How many fans are needed for intake/outlet? (in my case i'd use regular pc-fans)
--What- should be cooled: lcd only or also bulb itself?
-What other precautions do you suggest?
-Could a reflector cause a fried bulb because it's too close to it?
-How far away from the wooden case should the bulb be positioned in order to be safe?
...
-How many fans are needed for intake/outlet? (in my case i'd use regular pc-fans)
--What- should be cooled: lcd only or also bulb itself?
-What other precautions do you suggest?
-Could a reflector cause a fried bulb because it's too close to it?
-How far away from the wooden case should the bulb be positioned in order to be safe?
...
You want to give any type of hot-burning bulb at least 4-5 inches if not more from any wood or flamable material(the refelctor can be closer because it doesn't get quite as hot). I haven't ever heard of a refelctor causeing a bulb to burn out, but certainly you don't want it too close, because a bumb could cause it to touch the refelctor, wich would probably make it break.
careful design
With careful design a single 120mm fan can cool your panel and light. I didn't anticipate the heat I was getting on my panel at first and had to redesign my cooling circuit. 95f is really the limit on panel heat. Also I used aluminum 'flashing' to shield my wooden box, fan and ballast. My light is only an inch away from my enclosure and I have no problems. I'll be posting my cooling system design within a few days. 🙂
With careful design a single 120mm fan can cool your panel and light. I didn't anticipate the heat I was getting on my panel at first and had to redesign my cooling circuit. 95f is really the limit on panel heat. Also I used aluminum 'flashing' to shield my wooden box, fan and ballast. My light is only an inch away from my enclosure and I have no problems. I'll be posting my cooling system design within a few days. 🙂
Ehuwiko said:
Okay🙂 that was one of my concerns... i thought if the heat passes through the bulb twice it could be a problem, but i guess if nobody experienced any problems its safe
Does it help a lot if you put a piece of glass between the bulb and lcd, or does it cause a lot of light loss?
glass = good
I have a piece of glass before the optics (fresnels/LCD) and it does block some light, not too bad, but it stops A LOT of heat. It gets reasonably warm so I assume that the warmth it is getting would be gathered on the LCD had it not been there. Definately a good idea. I have my bulb about 1.5/2 inches from 3/4" plywood that it is mounted on (painted black) and the wood has cracked some and the paint has faded, but after the wood/paint got to a certain point it seems to have stopped getting any worse. I think that one major thing to prevent is non-polarized light from getting to the LCD. All non polarized light will be blocked by the LCD thus gernerating heat. Try to keep it at a minimum.
I have a piece of glass before the optics (fresnels/LCD) and it does block some light, not too bad, but it stops A LOT of heat. It gets reasonably warm so I assume that the warmth it is getting would be gathered on the LCD had it not been there. Definately a good idea. I have my bulb about 1.5/2 inches from 3/4" plywood that it is mounted on (painted black) and the wood has cracked some and the paint has faded, but after the wood/paint got to a certain point it seems to have stopped getting any worse. I think that one major thing to prevent is non-polarized light from getting to the LCD. All non polarized light will be blocked by the LCD thus gernerating heat. Try to keep it at a minimum.
I still cant for the life of me figure out why nobody uses Heat Absorbing Glass or an IR Filter. And I'm not talking about a 12"x9" piece... all you need is a little piece of heat absorbing glass right before your condenser lens with one fan blowing on it and your set. You can remove any and all glass or plexi you have "protecting" the LCD. Cause it's not protecting a thing.
Just make sure it's tempered and untinted.
Just make sure it's tempered and untinted.
Again... I cant for the life of me figure out why. Even your going to switch to a smaller bulb... and when you do your gonna need a condenser.
Plus this DIY projector project started in China. If you search the Chinese DIY boards... EVERY DIY projector built is using either an IR filter or heat absorbing glass. Just like "commercial" projectors.
Plus this DIY projector project started in China. If you search the Chinese DIY boards... EVERY DIY projector built is using either an IR filter or heat absorbing glass. Just like "commercial" projectors.
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