29
10) Press the button of one UPS, each UPS would start to turn on, all the UPS
would transfer to the Line mode together. Measure the output voltage of each
UPS separately to check if the voltage difference between them is less than 0.5V.
If the difference is more than 0.5V, the UPS need to be regulated.
11) Press the button of one UPS, each UPS would start to turn off and transfer
to the Bypass mode, switch on the output breaker of each UPS to parallel all the
output of UPS together.
12) Press the button of one UPS, each UPS would start to turn on , after turning
on, the UPS should work parallel in the Line mode.
How to join a new UPS to a parallel system:
1) First the parallel system must be installed one main maintenance bypass switch.
2) Regulate the output voltage of the new UPS separately: check if the output
voltage difference between the new UPS and the parallel system is less than
0.5V.
3) Ensure the bypass of the parallel system is normal and the bypass setting
is
″
enable
″
, remove the cover plate of maintenance bypass switch on the rear
panel of each UPS, the UPS system would transfer to bypass automatically. Set
the own maintenance bypass switch of each UPS from
″
UPS" to "BPS".
4) Set the main maintenance bypass switch from
″
UPS
″
to
″
BPS
″
, switch off the
main output breaker and the main input breaker, the UPS would shut down.
5) Ensure the UPS shut down totally, add the new UPS and reinstall the new UPS
parallel system by following step 1) to 9) of the last chapter-
″
How to install a new
parallel UPS system
″
.
6) Switch on the main input breaker and the main output breaker, and set the main
maintenance bypass switch from
″
BPS
″
to
″
UPS
″
, then set the UPS own
maintenance bypass switch from
″
BPS
″
to
″
UPS
″
and screw the maintenance
cover plate back again. Press the button of one UPS, each UPS would start
to turn on, after turning on, the UPS should work parallel in the Line mode.
How to remove a single UPS from a parallel system:
1) First the parallel system must be installed one main maintenance bypass switch.
2) Ensure the bypass of the parallel system is normal and the bypass setting is
"enable", remove the cover plate of maintenance bypass switch on the rear panel
of each UPS, the UPS system would transfer to bypass automatically. Set the
own maintenance bypass switch of each UPS from "UPS" to "BPS".