The UPS must be connected to an AC power outlet with fuse or circuit the outlet does not exceed the UPS's rated capacity (1350VA/810W for CST135XLU)
963800UserManual.pdf
F02: Battery Output Short fault (Unplug at least one piece of equipment from battery outlets and turn the UPS on again ) F03: Charger Fault (Contact CyberPower
CyberPowerUMCST150XLU1046903.pdf
To correct this, turn the UPS off and unplug at least one piece of equipment from the battery power supplied outlets Make sure the circuit breaker is depressed
1068693+OwnersManual.pdf