ST3 6-10kVA Service Manual Rev.1
Allis Electric Page 4 of total 12 September 2006
3. Troubleshooting
3.2 PFC Analysis:
In this section, some components you could check to see if failure occurs on PFC Correction circuit as shown below. Be
aware of F301, F302 fuse open indicates failure of this block. Please replace all faulty components before re-start the UPS.
6/10kVA-PFC-Right side
6/10kVA-PFC-Left side
Step
Checked components
Instrument
function
Reference
Value
Failure Mode
1
F301, F302
Ω
0
Ω
Open
(A, K)
Ω
2.6
M
Ω
Short or open
2
Q301
Q302
(G, K)
Ω
10
Ω
Short or open
Action ltem:
If all above-stated components are replaced well and UPS still can’t work, change the PFC
IGBT driver module.
