The temperature controller is a thermostat. According to the temperature change of the working environment, a physical deformation occurs inside the switch, which produces some special effects, a series of automatic control elements that produce on or off actions, or electronic components at different temperatures. Next, the different principles of the working state provide temperature data to the circuit for the circuit to collect temperature data.
According to the manufacturing principle of the thermostat, the thermostat is divided into:
1. Sudden jump thermostat: The models of various sudden thermostats are collectively referred to as KSD, common ones such as KSD301, KSD302, etc. The thermostat is a new type of bimetallic thermostat, mainly used as various electric heating When the product has overheat protection, it is usually used in series with the thermal fuse, and the jump thermostat is used as the primary protection. The thermal fuse is used as a secondary protection when the sudden temperature controller loses or fails to cause the overheating of the heating element, effectively preventing the burning of the heating element and the resulting fire accident.
2. Liquid expansion thermostat: when the temperature of the controlled object changes, the physical phenomenon (volume change) of the material (generally liquid) in the temperature sensing part of the thermostat corresponding to thermal expansion and contraction (volume change), and the sense The bellows connected together at the temperature part expand or contract. Using the principle of lever to drive the on-off action of the switch to achieve the purpose of constant temperature, the liquid expansion thermostat has the characteristics of accurate temperature control, stability and reliability, small temperature difference between opening and stopping, large temperature control adjustment range, and large overload current. Liquid expansion thermostat is mainly used for temperature control occasions in home appliance industry, electric heating equipment, refrigeration industry and so on.
3. Electronic temperature controller and electronic temperature controller (resistive type) are measured by the method of resistance temperature sensing. Generally, platinum wire, copper wire, tungsten wire and thermistor are used as temperature measuring resistors. These resistors Each has its own advantages. Most household air conditioners use thermistor type.
4. Pressure thermostat, change the thermostat to change the controlled temperature change into the change of space pressure or volume through the closed temperature bag and capillary filled with temperature-sensing working medium. When the temperature setting value is reached, pass The elastic element and fast instantaneous mechanism automatically close the contacts to achieve the purpose of automatic temperature control. It is composed of three parts: temperature sensing part, temperature setting main part, micro switch that performs opening and closing, or automatic damper. Pressure thermostat is suitable for refrigeration appliances (such as refrigerator freezer, etc.) and heaters and other occasions.