Heat Sensor

This is a basic circuit for a Heat Sensor. ~Every Circuit doesn't have Sensors so has to use Potentiometer as Sensor. ~Top most Potentiometer is sensor which varies according to heat it receives from surroundings. ~Remaining 4 Potentiometers are presets for Op-Amp. ~DON'T change their values. ~They are used to define voltage level. ~Op-Amp here is configured as Comparator. When Voltage on +ve is higher than voltage on -ve Op-Amp gives Output of 5V. Which drives the LED. ~Initially the sensor is at room temperature i.e. at 60% giving 2V which is lower than all preset levels. ~When you change the Sensor value to 50% First LED will turn ON. ~ Same way turn the Sensor upto 20% and all LED will light up one after other. Thus showing increasing temperature. ~I have run this circuit in Proteus and now planning to make it using Arduino which will replace all the Op-Amps. ~It is a small part of my college project which will work as temperature level indicator of the whole plant.

published 9 years ago