Step 8 Measure the bypass input voltage of each UPS.
1. Check that no Bypass abnormal alarm is generated for any UPS in the
system. Then, none of the UPSs supplies power.
2. Set the multimeter to the AC voltage position, connect the red probe to UPS 1
bypass input phase A, and connect the black probe to UPS 2 bypass input
phase A to measure the bypass input voltage difference between UPSs.
Perform the same operations on phases B and C. Complete the measurement
between every two UPSs in the parallel system. If the phase sequence is
correct and the voltage difference is less than 5 V, perform the subsequent
operations. If the phase sequence is incorrect or the voltage difference for a
phase between any two UPSs is greater than 5 V, power off the parallel
system completely, and check whether the bypass input cables for the UPS
parallel system are properly connected.
CA UTION
Exercise caution when performing operations with power on. There are many
electrified parts in the UPS wiring area. It is recommended that the test be
performed in the external power distribution area of the UPS.
Step 9 Clear the EPO state of each UPS. For details, see
.
Step 10 Measure the output voltage of each UPS.
1. Check that no Bypass abnormal alarm is generated for any UPS in the
system. Then, all UPSs in the system supply power in bypass mode.
2. Set the multimeter to the AC voltage position, connect the red probe to UPS 1
output phase A, and connect the black probe to UPS 2 output phase A to
measure the output voltage difference between UPSs. Perform the same
operations on phases B and C. Complete the measurement between every
two UPSs in the parallel system. If the phase sequence is correct and the
voltage difference is less than 5 V, perform the subsequent operations. If the
phase sequence is incorrect or the voltage difference for a phase between any
two UPSs is greater than 5 V, power off the parallel system completely, and
check whether the output cables for the UPS parallel system are properly
connected.
CA UTION
Exercise caution when performing operations with power on. There are many
electrified parts in the UPS wiring area. It is recommended that the test be
performed in the external power distribution area of the UPS.
Step 11 Turn on the output switch of each UPS.
Check that no alarm is generated for any UPS, and then turn on the output switch
for each UPS.
Ensure that the output switch on each UPS is ON and the load switch is OFF.
Step 12 Tap Paral. Inv. ON on the LCD screen Common Functions. The system transfers
to inverter mode.
UPS5000-H-(400 kVA-800 kVA)
User Manual (100 kVA Power Module)
8 Parallel System Commissioning
Issue 02 (2021-04-22)
Copyright © Huawei Technologies Co., Ltd.
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