Vertiv Liebert EXS 80kVA UPS, Руководство пользователя

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Vertiv™ Liebert EXS 80kVA UPS User Manual
6 Parallel System and LBS System
2. After confirming that the inverter of each UPS is normal, commission the parallel system, the specific
procedures are as follows:
a. Close the external and internal I/O switch of each UPS, and all UPSs are powered on at the same time.
After the start of the rectifier is finished, press the power button of one UPS to start the inverter, and
then the run indicator (green) will be on.
b. Start the inverter of the second UPS, check whether there is an alarm on the LCD, and confirm that the
UPS parallel works normally.
c. Follow the methods to start inverter of the third or the fourth UPS to connect the UPS into the parallel
system.
WARNING! 1. During the parallel power-on, confirm that the extenal output MCB of each UPS has
been closed, and that all the inverter output of the UPSs is connnted parallelly.
2. During the parallel power-on, confirm that the system is working normally, and then feed
power to the load, to void load power failure.
6.4.4. Maintenance Bypass Procedures
WARNING! If the UPS system is composed of more than 2 parallel UPS modules, and the load
capacity exceeds the single module capacity, do not use the internal maintenance bypass
switch.
This operation will make the load transfer from UPS power supply protection state to direct connection
with AC input bypass state.
CAUTION: Power supply interruption danger of the load
Before performing this procedure, you should check the LCD information first, and make sure
the bypass is normal and inverter synchronized. Otherwise, it may result in the load power
interruption for a while.
1. Press the power button of each UPS to shut down the inverter, till all the UPSs in parallel system
transfer to Bypass mode.
2. Close the UPS external total maintenance bypass switches, and do not close the internal maintenance
bypass switch Q3 of each UPS.
3. At this moment, the external total maintenance bypass should be parallel connected with each UPS’s
bypass.
4. At this moment, the LCD of each UPS displays ‘ Maint. Switch Closed’.
CAUTION: When the UPS is in maintenance mode, the load does not have the mains abnormal
protection.
5. Press the remote EPO button of each UPS for 2s (if any), or unplug the EPO terminal of each UPS
to stop the operation of rectifier, inverter, bypass and battery, but this action will not affect the
maintenance bypass power the load normally.
NOTE: In maintenance mode, the load is directly fed by the mains power instead of the pure AC power
from the inverter.
6. Disconnect the main input switch Q1, bypass input switch Q2, output switch Q5 of each UPS in turn.
At the moment, all the internal power supply is off and the LCD does not display any more.