Failure phenomenon: After UPS is turned on, there is no display on the panel, and UPS does not work.
Judging from the fault phenomenon, its failure in the electricity input, battery and municipal electricity detection section and battery voltage detection circuit:
1) Check whether the city electric input fuse is burned.
2) If the city electric input fuse is intact, check whether the battery insurance is burned, because some UPS will turn off all outputs and display of UPS when the self -inspection does not reach the battery voltage.
3) If the battery is intact, check whether the municipal electricity detection circuit work is normal. If the municipal electricity detection circuit work is abnormal and UPS does not have a market -free startup function, UPS will also turn off all output and display.
4) If the city's detection circuit works normally, check whether the battery voltage detection circuit is normal.