Temperature limit Relay


Posted on Mar 22, 2013

This circuit, is basically a resistance ? sensing window switch, except that the ?resistor? takes the form of an NTC thermistor and the circuit thus responds to temperature. TH1 must have a resistance in the range 500ohm - 9Kohm. RV1 is used to set half ? supply volts on the RV1 ? TH1 junction at the ?mean? temperature.


Temperature limit Relay
Click here to download the full size of the above Circuit.

Part List R1=4.7Kohm TH1=NTC thermistor 500ohm.....9Kohm Q2=BC214L R2=2.2Kohm D1-2=1N4148 RL1=12V Relay >120ohm RV1-2-3=10Kohm pot. D3=1N4001




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Phone Line In use LED
Electronic-bagpipe
Ultrasonic Sensor Circuit
Solid State Relay Required Only 50uA Drive Current
arduino + optotriac based ac dimmer blinking severely
mjr7 mk3 mosfet audio power amplifier 70w
Simple Square Wave Generator with 7400
High Quality Intercom
Logic Probe With Sound
Dancing Robots
Direct coupling audio power amplifier configuration A741 circuit



Top