The over-voltage and under-voltage protector is an electrical safety device that monitors line voltage. It can automatically cut off the power supply when the voltage is over-voltage, under-voltage, or over-current, and close it after a delay after the voltage returns to normal to avoid damage to home appliances and electrical equipment due to continuous abnormal voltage. Rated voltage 230V, rated current 63A, 1P+N, fast response, delayed self-recovery function. Installed after the main opening of the distribution box, it is suitable for home, shop and industrial front-end power distribution protection in areas with power grid fluctuations.