5 Operation Guide
Three-Phase UPS (10kVA-160kVA) Series
User Manual
86
If the voltage difference of output three-phase of UPS1 and UPS2 is less than 10V, the phase-locking
is normal in mains, or it is abnormal.
Normal=>Step 9
Abnormal=>Step 12
Step 9
Switch off the mains switches of UPS1 and UPS2 and check whether the voltage difference of output
live wire of UPS1 and UPS2 is normal.
If the voltage difference of UPS1 and UPS2 is less than 10V, the phase-locking is normal on battery
status, or it is abnormal.
Normal=>Step 10
Abnormal=>Step 12
Step 10
Switch on the output switch of UPS2 and check whether the three-phase output voltage in parallel is
normal by multimeter and clamp meter respectively.
If the voltage is less than 10V, UPS2 output is normal, or it is abnormal.
Normal=>Step 11
Abnormal=>Step 12
Step 11
Switch on the output switch of UPS1 and UPS2. Check whether the loop current in parallel is normal
by clamp meter.
If the loop current is less than 10A, the output voltage is normal in parallel system, or it is abnormal.
Normal=>Step 13
Abnormal=>Step 12
Step 12
Remove fault when power down and redo the Step 1.
Step 13
If all tests are normal, switch on the load switches in the client and finish parallel system startup.
At the moment, parallel system can supply power for load. The power on sequence for load refers to
the requirements of single-unit.
----End
5.4.2 Close Parallel System
Step 1
Close all loads and keep UPS running without load for 10 minutes to exhaust heat.
