The utility model relates to an arc light protective device's detecting system, including arc light protective device, filtered light sensor, arc generator, relay protection testing device, filtered light sensor inserts arc light protective device, and the light struck that filtered light sensor sent is on filtered light sensor, and the arc generator passes through wireless network and relay protection testing device communication connection, the arc generator includes arc light light source, microcontroller, wireless communication module and power module, and relay protection testing device includes microprocessor, current generator, wireless communication module, power module, switching value input interface, alternating current output interface, and switching value input interface connects wireless communication module 1's action export, alternating current output wireless communication module 3 wireless communication module 1's interchange sampling interface. This system can accomplish filtered light sensor's check -up and a whole set of arc light protective device's logic calibration and transmission experimentally, reduces the condition that the arc protection mistake was moved, was refused.