Guys, if you’re looking for a highly accurate Electronic Temperature-controlled relay, but you don’t want to buy it at the electronic store. You should have a sneak peek at this 0 to 100oC Electronic Temperature-controlled Relay.
This electronic temperature-controlled relay is slightly different from the others, as it can be used in applications, especially where automatic temperature control is needed.
For your information, the circuit switches a miniature relay ON/OFF. The single-chip temperature sensor LM35 is necessary for this project, as it detects the temperature changes. The relay is automatically actuated when the LM35 detects a temperature higher than the preset level. Otherwise, the relay is de-energized if the temperature falls below the preset temperature.
Do keep in mind that the LM35 temperature sensor is the heart of the circuit, which is factory-calibrated in the Celcius scale with a linear Degree to Volt conversion function. This means all the output voltage changes linearly with temperature from 0V to 1000mV, or from 0oC to 100oCrelatively.
Another advantage of this circuit is it can be powered by an AC or DC 12V supply or battery (100mA).