4. Use a multimeter to measure the impedance between phases A, B, and C of
the mains/bypass input and AC output of any two UPSs. If the measured
result is low conducted resistance, check whether the mains/bypass input and
AC output phase sequences of the two UPSs are correct.
Step 2 Trigger EPO on each UPS.
1. Press the EPO switches connected to the dry contact cards of all UPSs one by
one, or remove the 4-pin terminals from the EPO ports on the dry contact
cards of all UPSs, or remove the general EPO switch.
2. If a single UPS is not powered off after commissioning, verify on the
monitoring screen that EPO has been activated successfully.
Step 3 Install parallel cables between parallel cabinets.
Figure 8-1 Control cable connections in a parallel system of four UPSs
Step 4 Power on the parallel system.
1. Turn off the output switch of each UPS to ensure that the output of each UPS
is independent.
2. Turn on the external bypass input and mains input power distribution
switches.
If the input power is normal, the rectifier starts automatically. The MDU starts and
displays the Huawei logo and a progress bar. Wait until the MDU starts properly.
Step 5 Check that the software versions of all UPSs are consistent.
On the LCD of each UPS, choose System Info > About > Version Info and check
whether all software versions are consistent. If not, update all software versions to
be consistent.
Step 6 Set parallel parameters for each UPS.
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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