Here is a wireless light switch circuit which you can use as a substitute for physical contact switch that may be dangerous if there is any shorting. This circuit is simple enough to be built with an infrared wireless medium, which is an infrared LED and phototransistor.
The light switch circuit described here requires no physical contact for operating the appliance. You just need to move your hand between the infrared LED (IR LED1) and the phototransistor (T1). The infrared rays transmitted by IR LED1 is detected by the phototransistor to activate the hidden lock, flush system, hand dryer or else.
Wireless Light Switch Circuit
Wireless Light Switch Circuit
This wireless switch is very stable and sensitive compared to other AC appliance control circuits. It is simple, compact and cheap. Current consumption is low in milliamperes. The circuit is built around an IC CA3140, IRLED1, phototransistor L14F1 and other discrete components.
How It Works
The working of the circuit is simple. In order to switch on the appliance, you simply interrupt the infrared rays falling on the phototransistor through your hand. During the interruption, the appliance remains on through the relay. When you remove your hand from the infrared beam, the appliance turns off through the relay. Download file.
Electronic Wireless Light Switch Circuit Schematic
Here is the circuit of the wireless switch assuming the above work. The circuit is very simple and easy to understand even by a beginner.
Wireless Light Switch Circuit Schematic
 
Top