What is an overvoltage and undervoltage protector?

An overvoltage and undervoltage protector (OVP) is an intelligent protection device that monitors grid voltage and automatically cuts off power when voltage is abnormal (too high or too low). Its core functions include:

1. Core Function

Overvoltage Protection: When the voltage exceeds a set upper limit (e.g., 275V ± 5V), it disconnects the circuit to prevent damage to electrical appliances caused by high voltage.

Undervoltage Protection: When the voltage falls below a set lower limit (e.g., 170V ± 5V), it disconnects the power supply to prevent abnormal operation of electrical appliances under low voltage.

Automatic Recovery: When the voltage returns to normal, power can be automatically or manually restored.

2. Working Principle

A voltage detection unit (e.g., a comparator circuit) monitors voltage in real time. When an abnormality occurs, a latching relay is triggered to cut off the circuit. Some high-end models also integrate overload and leakage protection.

3. Application Scenarios

Home Use: Protects precision appliances such as air conditioners and refrigerators from damage caused by voltage fluctuations.

Industrial Equipment: Used in distribution boards and electrical control boxes to address issues such as three-phase voltage imbalance.

4. Installation Necessity

National regulations stipulate that the tolerance for single-phase 220V voltage is ±10% (198V-242V). Exceeding this range can easily cause electrical failures. This installation effectively prevents the risk of equipment burnout or fire caused by voltage anomalies.