Performing Epo; Isolating A Faulty Ups From A Parallel System - Huawei UPS5000-H User Manual

UPS5000-H-(400 kVA-800 kVA)
User Manual (100 kVA Power Modules)
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8.3 Performing EPO

Procedure
Step 1 Turn on the EPO switches connected to the dry contact cards on all UPSs one by
one or the general EPO switch.
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8.4 Isolating a Faulty UPS from a Parallel System

Context
● Only authorized technical engineers are allowed to isolate a faulty UPS from
● Before maintenance, use a multimeter to check faulty parts for dangerous
● If the output switch does not have the neutral wire isolated, do not touch the
● When the parallel system works properly, do not turn off the output switch of a
Procedure
Step 1 If the UPS needs to be disconnected, check whether the capacity of the remaining
UPSs in the parallel system meets the onsite load requirements.
Step 2 Turn the ready switch on the bypass control module to the not ready state. The
system reports alarm 0047-002 Not ready, which is normal. If the faulty UPS
works in bypass mode, there is no output. If the faulty UPS works in normal mode,
choose Common Functions > Inv. OFF on the LCD of the faulty UPS to shut down
the inverter. Then, the UPS has no output, and the other UPSs continue to work in
inverter mode.
Step 3 Turn off the output switch of the faulty UPS or the external output power
distribution switch.
Issue 03 (2021-08-03)
NO TE
● Perform only step 1 if you only need to shut down the UPS inverters to switch the
system to bypass mode without powering off loads.
● If you need to power off the entire UPS system, perform all the preceding steps.
CA UTION
the parallel system. Before the operation, consult professional maintenance
personnel.
voltages.
neutral wire.
single UPS if the UPS does not stop supplying power. Otherwise, the parallel
system may become abnormal.
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