Aug 13, 2021
How to control the temperature of the electric heating tube?
You can use the thermostat solid state relay to control the temperature of the electric heating tube. The following is its working principle:
The simplest temperature controller is a bimetallic sheet. It works by using the principle of different expansion coefficients of two different metals. The two different metallic sheets are pasted together. When the temperature rises, due to the different expansion coefficients, the metal The film will bend to the side with the smaller expansion coefficient to drive the switch. When the temperature drops, it will bend to the other side. The thermostat switch in the water dispenser (operating temperature 80℃) and the heat preservation switch in the rice cooker are used. This kind of thermostat.
Industrial thermostats generally use semiconductor or resistance temperature sensors (thermistors). When the temperature changes, the resistance of the semiconductor changes accordingly, and then the change is amplified by the amplifying circuit. When the temperature reaches the set temperature The value corresponds to a corresponding resistance value. At this time, the amplifying circuit will output a switch signal to the corresponding actuator, such as disconnecting the heating circuit, so that the temperature will not be too high. The principle is the same when the temperature decreases.
