Relay connects to the collector of transistor

Relay connects to the collector of transistor. When the current drives, the switch is closed, then the solenoid valve is energized, then the circuit is closed, then hair dryer blow air. While there is not having the current, Blade Hand Dryers the switch is turned off, then the solenoid valve is not energized, then the circuit is disconnected, then hair dryer does not blow hot air. At the same time, a diode acrosses the relay parallel protection. Light-emitting diode in the circuit is a display, commercial hand dryer showing hair dryer stsrted