A temperature controller is a device used to hold the desired temperature at a specified value . ... If it falls below the set temperature, it sends a signal to activate the heater to raise the temperature back to the setpoint. Thermostats are also used in refrigerators. Video Specifications: Size: 1/16 DIN (48 x 48 mm) Functions: ON/OFF control Number of control loops: 1 Temperature input type: J Number of alarm outputs: 0 Supply voltage AC: 100-240 V Control output: Relay Terminal: Plug-in Package Includes: 1 x Sinny SN E5C2 Temperature Controller 0-100C