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NE Series (20-30kVA)
User Manual
Chapter 4 Operation Guide
If the output loop current is less than 30A, it means the output voltage of parallel system is
normal.
Normal =>Step 13
Abnormal =>Step 12
Step 12 After powering down and getting rid of faults, perform Step 1.
Step 13 After testing normally, close the switch of user load, then the starting of parallel system will
be finished.
At this moment, the parallel system can supply power for load. The power on sequence of load,
please refer to the requirements of single unit.
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4.5.2
Shut Down Parallel System
Step 1 Close all loads.
Step 2 Close each inverter according to the shutdown steps of the UPS.
Step 3 Perform the shutdown steps of the UPS, and disconnect the relative input and output switches
of each UPS.
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It is recommended that you do not switch on or switch off the parallel system frequently when it is
working properly.
4.5.3
Exit Parallel System Online
When one UPS fails, it will exit from the parallel system automatically. In addition, an audible and
visual alarm is generated. You can follow the procedure showed in Figure4-2to exit the faulty UPS to
achieve online thermal maintenance or replacement.
Figure 4-2 Exit a faulty UPS
Close the fault UPS according
to shutdown procedure
Disconnect the parallel units
air switch to UPS in the
parallel distribution box.
