M90 & M90L Service Manual
Repair
In this section, some debug skills are listed to help you finding the failed components and problems as soon as
possible. Before proceeding the following steps, we strongly suggest to read previous section
for trouble shooting first.
Basic Instruments and Tools
1. One computer with RS232 port and one standard RS232 cable;
2. Wire cutters and clamps;
3. One electric soldering iron;
4. One multimeter;
5. One oscilloscope(voltage and current probe needed);
6. Diagonal pliers, snipe nose pliers, cross screw drivers(150mm/75mmlength), flat screw drivers (75mm length)
and PVC insulating tapes etc;
7. Make-self tools including Balance voltage test equipments, current limiting resistors, tubes and clamp termi-
nals with different specifications;
QuickStart
Before any detail check for UPS, please check the components listed in the following table. This action could help
you find problem quickly and make debug procedures go smoothly.
Note: Make sure that the capacitor voltage is lower than the safety voltage before disassembling any parts to do
checking procedure.
Power module
IPOP Board
Component Type
SCR
Diode
MOSFET
FUSE
PFC Board
Component Type
IGBT
Xtreme Power Conversion Corporation
Checked components
Q7,Q8,Q12,Q16,Q4,Q6,Q13,Q15,Q
3,Q5,Q9,Q14,Q1,Q2,Q10, Q11,Q19
,Q20,Q21,Q24,Q17,Q18,Q22,Q23,Q
46,Q47,Q48,Q49
,Q50,Q51,Q28,Q29,Q32,Q36
D36,D7,D9,D35,D11,D32,D13,D25,
D2,D1,D3,D4,D5,D7,D8,D1
0,D12,D14,D16,D21,D22
Q27,Q30,Q35,Q31,Q52,Q53
F15,F14,F10,F11,F12,F13,F22,F23,F
24,F19,F20,F21,F16,F17,F18
Checked components
Q4,Q10,Q17,Q1,Q7,Q14,Q5,Q16,Q
12,Q2,Q8,Q15,Q6,Q11,Q18,Q3,Q1
3,Q9
Uninterruptible Power Supply
Failure condition
A-K Short or open
Short or open
D-S short or open
open
Failure condition
C-E short or open
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