one of the biggest concerns when building a projector has always been the excessive amount of heat generated by the bulb. us projector builders usually take steps to prevent heat isues, like installing fans or painting the case black so that it will deflect uv radiation thus not heating up.
However, some of us like to have the ability to run the fan for longer after the projector lamp and lcd are shut off.
there are three ways of doing this:
1. wire a separate switch for the fans so that you can shut of everything except the fans.
2. wiring in a temperature sensor, this is a pretty popular solution and the parts can be found at this site's store.
3. wiring a delay circuit to run your fans 5 minutes after projector shutoff.
with my projector, I plan to do option 3. here is how it will be done:
and a mini faq:
1. what about your circuit for your lcd, where is it?
I did not wire this into these schematics because my lcd has it's own separate circuit, I bought a controller- laptop lcd kit, which has it's own ac adaptor.
2. what did you use for your fan delay circuit?
this link should answer that question:
http://www.newegg.com/Product/Product.aspx...N82E16835119056
NOTE: I have not begun assembling my projector yet, and thus, none of this has been tested. but the theory is sound and should work. not to mention this solution cost a hell of alot less than any other solution I have came across.
