Working principle: 1.Voltage monitoring: The AVP digital display overvoltage/undervoltage protector will monitor the voltage of the input power in real-time. It is usually connected to the power line to detect voltage fluctuations and changes. 2.Threshold setting: Users can set upper and lower threshold values, which are the highest and lowest voltage limits. In general, when the voltage exceeds the set maximum limit or falls below the set minimum limit, the protector will trigger. 3.Trigger protection: When the voltage exceeds the set range, the protector will trigger the protection mechanism, usually cutting off the power supply or taking other measures to ensure that the electrical equipment is not damaged.