Features Brand new and high quality.Can select cooling or heating working mode. High temp alarm, when measure temp reach to the setting temp, controller will alarm. Set highest/ lowest upper limit temp to avoid accident. Automatically start cooling or heating for constant temperature. Temperature calibration, you can calibrate temp according to requirement. Specifications:Material: electronic element Voltage:DC 12V/24V /110-220V(Optional)Power:120/240/1500W (Optional)Weight: Approx.48g/1.7oz Package list: 1 x Digital Thermostat Temperature Alarm Controller Sensor Circuit connection: refer to the circuit diagram to connect the power supply and load. At this time, the digital tube (top) displays the actual measured temperature value, and the digital tube (bottom) displays the preset temperature. If the temperature sensor is missing or damaged, the digital tube will display "-- --", and the buyer must check whether the temperature sensor is installed before using it.The temperature control output is a 10A relay, which can meet various high-power loads. Please make sure the circuit is correct.Indicator light, digital tube status:Indicator light: off means the relay is disconnected, and on means the relay is closedDigital tube: display "-- --",1. Check whether the temperature sensor is missing or damaged2. High temperature protection of heating mode3. Low temperature protection in refrigeration modeThe relay in protection mode is automatically disconnected.Use of keys: the thermostat panel has three keys, keys + keys - SET keysKey + : fast accumulation of valuesKey -: to achieve the rapid decline of the valuePress Restart: Restart the button Package List