Surge protector, also known as lightning arrester, lightning arrester, is an electronic device that provides safety protection for various electronic equipment, instruments, communication lines, and low-voltage electrical lines. It is suitable for AC 50/60Hz, rated voltage 380V power supply system or photovoltaic system, to protect the indirect lightning and direct lightning impact or other instantaneous overvoltage surge, to meet the surge protection requirements of household, tertiary industry and industrial fields, with relative phase, relative ground, relative midline, midline to ground and its combination protection mode.

Backup Protector, The front end of the surge protector loop must be in series. The backup protector required by the manufacturer must be installed. Because current fuses and MCBS cannot work with SPD, when the power supply is abnormal or SPD deteriorates and fails, the device is damaged by lightning, and the normal operation is seriously affected
The SPD special external backup protector is connected in series on the SPD circuit, and the internal current sorting channel device is used to realize the small power frequency current flow rate break. High current lightning impact does not trip. To achieve the power frequency small current SPD fire protection, lightning impact SPD continuous protection; SCB products should only be used for SPD return current protection, or backup current protection should not be used in other situations.