46
6. Maintenance
This chapter introduces UPS maintenance, including the maintenance instructions of
power module and monitoring bypass module and the replacement method of dust
filter.
6.1 Precautions
1. Only certified engineers are authorized to maintain the UPS.
2. The components or PCBs 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, measure the voltage between operating
parts and the earth with multimeter 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. Wait 10 minutes before opening the cover of the power module or the bypass after
pulling out from the Cabinet.
6.2 Instruction for Maintaining UPS
For the maintenance of the UPS, please refer to chapter 5.2.4 for the instruction to
transfer to maintenance bypass mode. After maintenance, re-transfer to normal mode
according to chapter 5.2.5.
6.3 Instruction for Maintaining Battery string
For the Lead-Acid maintenance free battery, when maintenance the battery according
to requirements, battery life can be prolonged. The battery life is mainly determined
by the following factors:
1. Installation. The battery should be placed in dry and cool place with good
ventilation. Avoid direct sunlight and keep away from heat source. When installing,
ensure the correct connection to the batteries with same specification.
2. Temperature. The most suitable storage temperature is 20 ºC to 25ºC. The battery
life will be shortened if the battery is used under high temperature or in deep
discharging status. Refer to product manual for details.
3. Charging/discharging current. The best charging current for the lead-acid battery is
0.1C .The maximum current for the battery can be 0.3C.The suggested discharging
current is 0.05C-3C.
4. Charging voltage. In most of the time, the battery is in standby state. When the
utility is normal, the system will charge the battery in boost mode (Constant
voltage with maximum limited) to full and then transfers to the state of float
charge.
5. Discharge depth. Avoid deep discharging; which will greatly reduces the life time
of the battery. When the UPS runs in battery mode with light load or no load for a
long time, it will cause the battery to deep discharge.
6. Check periodically. Observe if any abnormality of the battery
，
measure if the
voltage of each battery are in balance. Discharge the battery periodically.
Summary of Contents for EA990RT G5 10
Page 4: ......
