PLEASE HELP ME. I have a on/off button that controls one of my fans inside of the PC. And I want to replace it with the light sensor (the same kind that is in the night or garden light) But when i remove the switch and replace it the a light sensor it just turn of the the circuit with or without light. I want to ti work the same as in the night like. When I turn on the light the fan stops and when the light goes off the fan starts. PLEASE HELP. PLEASE.