Input Fuse Is Burnt - Ablerex 3 MS series User Manual

4.3.

Input Fuse is burnt

Check Items
The IGBT of Inverter Stage is out of order
UPS Output Short Circuit or Overload
PFC is abnormal
FIG. 4.3
Trouble-shooting
1. Check the related circuit as shown in fig.4-4.
Check Q14, Q13, D24, D25, R118 and R120
are defective. If Q14¡BQ13 is abnormal, U7,U8
need to be replaced, too.
2. Check Q12, U6¡BBD1 in PFC circuit (fig4-3).
If Q12 is abnormal, replace both U6 and Q12.
3. Check D30-D33, Q15-Q20 and U9, refer to
fig.4-5.
Remove the output load. If the UPS works
Normally, it means the output load connected is
in short circuit or overload.
1. Check the related circuit as shown in fig.4-3.
2. Check if the PFC driving IGBT 20N60(Q12) and
the photo coupler IC PC923( U6) are abnormal.
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