8
Parallel System Commissioning
8.1 Starting a Parallel System
Prerequisites
CA UTION
● Before starting a parallel system, ensure that each UPS has been commissioned
(see
7.1 Powering On and Starting the UPS
● Choose Monitoring > UPS System > Running Parameter > System Settings
on the WebUI of each UPS and set EPO detection to Enable.
● If you commission the parallel system where UPSs are not powered off after
they are commissioned individually, skip step 4. In addition, ensure that step 1
is performed before commissioning a single UPS.
● Ensure that all load circuit breakers in the system are OFF. Do not start loads
before the parallel system is started.
● Before connecting parallel cables, if you turn on the external output switch of
the rack by mistake, the system may report alarm 0570-002 BPM unit
abnormal. In this case, you need to power off the rack to clear the alarm.
Procedure
Step 1 Check before power-on: Ensure that the mains input, bypass input, and AC output
cables of each UPS in the parallel system are connected in the same phase
sequence.
1. Check that the general input and output switches are OFF.
2. Check that power cables to all UPSs are connected in parallel.
3. Use a multimeter to measure the impedance between phases A, B, and C of
the mains/bypass input and AC output of any UPS. If the measured result is
low conducted resistance, check whether the cables to each UPS are short-
circuited.
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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