Subscribe by email

Humidity detector circuit

This humidity detector circuit diagram is very simple and uses few components and can be used for activation of an electronic devices when the detector senses a certain humidity.
The sensor is constructed from two pieces of copper placed at a short distance of each other. when the electrical resistance of copper conductors drops below a certain value, Schmit trigger built using transistors T1 and T2 switch. Bistable multi-vibrator is flip through C1, so that at point B there is a low voltage (relay triggers).
Relay is activated when the resistor R6 is connected to point B but the point A.
The circuit has a low and requires a 5 volt DC power supply.

Electronic Circuits: 
Circuit Diagram: 
Humidity detector circuit electronic project schematic