OPTI-UPS MD120L - Manual (Page 49)

46 Chapter 5 Maintenance
46
Chapter 6 Maintenance
This chapter introduces UPS maintenance, including the maintenance instructions of power module,
monitoring bypass module and the change method of dust filter.
6.1 Instruction to Power, Bypass, and Output Power Distribution
Module
6.1.1 Precautions
1. Only maintaining engineers can maintain the power module and monitoring bypass module.
2. In principle, the power module and bypass module should be disassembled from top to bottom, so
as to prevent any inclination from high gravity centre of the cabinet.
3. To ensure the safety before maintaining power module and bypass module, be sure to use a
multimeter to measure the DC bus capacitor voltage and ensure the voltage is below 60V before
operation, and use a multimeter to measure the voltage between operating parts and the earth to
ensure the voltage is lower than hazardous voltage, i.e. DC voltage is lower than 60Vdc, and AC
maximum Voltage is lower than 42.4Vac.
4. Bypass module doesn’t support any hot insertion and extraction, only when UPS is in maintenance
bypass mode or UPS is completely power off, the bypass module can be disassembled.
5. The module can be maintained 10 mins after extracting power module and bypass module which
can be inserted into the cabinet 10 mins later.
6.1.2 Instruction to Power Module
Suppose UPS were in normal mode, and bypass were normal, a module shall be maintained at
first.
1. Press OFF of the module with a pin point or other tiny matter, the module will shut down
automatically and exit the system
Note: ensure if the remaining module will be overload when exiting a module. If there’s any risk of
overload, transfer the whole UPS system to bypass, followed by other operations.
2. Take off the fixing bolt on the two sides of front and back plate of power module 10 mins later;
extract the module from the cabinet.
3. After maintaining the module, push the module into the equipment cabinet (the interval between
two modules shall be more than 10s), fix the screws on the two sides. Then the module will be
connected to UPS system automatically.
6.1.3 Instruction to Bypass Module
Suppose UPS were in normal mode, and the bypass were normal:
1. Select LCD touch screen manual switch of bypass, the UPS power will be supplied by bypass.
2. Close maintenance bypass switch, the UPS power will be supplied by maintenance bypass.
3. Open UPS output switch and input switch.
4. Open external battery switch.