34
6.3 Input Fuse is burnt
FIG. 6.3
Check Items Trouble-shooting
The IGBT of Inverter Stage is out of order 1. Check the related circuit as shown in fig.6-
Q32, D15, D16, R159, R163, R169
and R172 are defective. If Q29-Q32 are
abnormal, the U8 & U9 need to be replaced,
too.
2.Check Q5, U4 、
3).If Q5 is abnormal, replace both U4 and
Q5.
3. Check D32-D35, Q12-
U7, Refer to fig.6-5.
UPS Output Short Circuit or Overload Remove the output load. If the UPS works
Normally, it means the output load connected is
in short circuit or overload.
PFC is abnormal 1.Check the related circuit as shown in fig.5-3.
2.Check if the PFC driving IGBT 30N60(Q5) and
the photo coupler IC PC923( U4) are abnormal.