"24V DC Cooling Fan" switching device according to the security, good flexibility, good contact when the power is turned on and off. The switch has the keys and touch-type variety. "24V DC Cooling Fan" key switch when you press a key there should not be two key phenomena connected, each key is pressed, the reset must be flexible. Timing devices require accurate timing, rotating flexible, no jamming or friction panel phenomenon, normally open and normally closed position should be controlled and reliable. Knob, switch operation should be issued crisp sound, accurate positioning. Tactile Switches Tactile switch command to be accurate and reliable, but requires significant difference between the stall speed, "24V DC Cooling Fan" slow stall speed should be less than 70% faster document. Proper manufacturer name, model specifications, rated power, rated voltage, power and other indicators on the types and frequency of fan nameplate.