Start
Line mode Bat mode
Whether the Output voltage is exceeds
the output voltage range spec
Y
N
Whether the safety relay is stuck
END
Y
Whether the Driver circuit of safety
relay is Damaged
N
END
Y
Whether the Main relay is stuck
Y
END
Y
Whether the AVR/BOOST/BUCK relay is
stuck
N
END
Y
Replace PSDR and IO
board
N
N
N
UPS
UPS
PSDR
PSDR
Restart ups and no fault
END
Y
Replace CNTL board
N
END
CNTL
CNTL
Restart ups and no fault
Replace UPS
N
END
Y