15
the UPS will enter Bypass mode. If the UPS is in maintenance Bypass mode, turn the maintenance
switch to “UPS” position and then turn on the UPS.
3-5. Parallel Operation
1. Parallel system initial startup
First of all, please make sure all of the UPSs are parallel models and have the same configuration.
1) Turn on e ach UPS to AC mod e re spectively (Refer to section 3-4(1)). Then, measure the inverter
output voltage of each phase for each UPS to check if the inverter voltage difference between
actual output and setting value is less than 1.5V (typical 1V) with multimeter. If the difference is
more than 1.5V, please calibrate the voltage by conf iguring inverter voltage adjustment (Refer to
Program 15, 16 and 17, section 3-7) in LCD setting. If voltage difference remains more than 1.5V
after calibration, please contact your local distributor or service center fo r help .
2) Calibrate the output voltage measurement by configuring output voltage calibration (Refer to
Program 18, 19, and 20, section 3-7) in LCD setting to make sure the difference between real
output voltage and detected value of UPS is less than 1V.
3) Turn off each UPS (Refer to section 3-4(7.)). Then, follow the wiring procedure in section 2-4.
4) Remove the cover of parallel share current cable port on the UPS, connect each UPS one by one
with the parallel cable and share current cable, and then screw t he cover back.
5) Turn on the parallel system in AC mode:
a) Turn on the line input br eaker of each UP S( for dual input, also turn on bypass input breaker).
After all UPSs enter to bypass mode, measure the output voltage b e tween two UPS for the
same phase to make sure the phase sequence is corre ct . If these two voltage differences are
near to zero, that means all connections are correct. Otherwise, please check if the wirings ar e
connected correctly.
b) Turn on the output breaker of each UPS.
c) Turn on eac h UPS in turns. After a while, the UPSs will enter to AC mode synchronously and
then, the parallel system is completed.
6) Turn on the parallel syste m in B at te ry mode:
a) Turn on the battery breaker (only available in long-run model) and output break er of each UPS.
b) Turn on any UPS. A few seconds later, the UPS will enter to battery mode.
c) Then, turn on another UPS. A f ew seconds later, the UPS will enter to battery mode and add to the
parallel system.
d) If you have the third U PS, f ollow the sam e pr oce du re of c). Then, the parallel system is complete.
If more detailed information is needed, please contact supplier or service center for parallel
operation instruction.
2. Add one new unit into the parallel system
1) You can not add one ne w unit into the pa rallel s ystem w hen whole system is runnin g. You must cut
off the load and shutdown the system.
2) Make sure all of the UPS are the parallel models, and follow the wiring refer to section 2-4.
3) Install the new parallel system refers to the previous section.
3. Remove one unit from the parallel system
There are two methods to remove one unit from the parallel system:
First method:
1) Press the “OFF” key twice and each time should be lasted for more than 0.5s. Then, the UPS will
enter into byp a s s mode or no output mode without output.
2) Turn off the output breaker of this unit, and then turn off the input breaker of this unit.
3) After it shuts down, you can turn off the battery breaker (for long-run model ) and remov e the