ABB 8408608 User Manual page 19

3 I N S TA L L AT I O N
6. Turn on the input breakers for the parallel UPS.
7. Hold button for more than 1 s on one UPS in
the system; the system will then switch to
line mode.
8. Check the output voltage of each UPS
separately and check if the difference in output
voltage is less than 0.5 V among the units in
the parallel system. If the difference is more
than 0.5 V, the UPS need to be regulated.
9. If the difference in output voltage is less than
0.5 V, turn off the input breakers to let the
UPS shut down. Then switch on the output
breakers for all UPSs.
10. Switch on the input breakers for the parallel
UPS. Hold button for more than 1 s on one UPS
in the system; the system will then switch to
line mode. After these operations, the system
will work normally in parallel mode.
WIRING REQUIREMENT:
1. IF THE DISTANCE BETWEEN THE UPS
AND BREAKER PANEL IS LESS THAN 20
METERS IN A PARALLEL SYSTEM, THE
LENGTH DIFFERENCE BETWEEN INPUT
AND OUTPUT CABLE OF THE UPS IS
REQUIRED TO BE LESS THAN 20%.
2. IF THE DISTANCE BETWEEN THE UPS
NOTE
AND BREAKER PANEL IS MORE THAN 20
METERS IN A PARALLEL SYSTEM, THE
LENGTH DIFFERENCE BETWEEN INPUT
AND OUTPUT CABLE OF THE UPS IS
REQUIRED TO BE LESS THAN 5%.
How to add a new UPS to a parallel system:
1. Firstly, a main maintenance mechanical
switch or static switch should be installed
in the parallel system.
2. Regulate the output voltage of the new UPS:
check if the output voltage difference between
the new UPS and the parallel system is less
than 0.5 V.
3. Ensure the bypass of the parallel system is
normal and the auto bypass setting is at
"enable," then press the button to turn off
the UPS, the UPS will switch to bypass mode.
4. Set the main maintenance switch or static
switch from "UPS" to "BPS," then switch off
the main output breaker, input breaker and
mains breaker. The UPS will then shut down.
5. Connect the cable and wire for the new UPS.
6. Switch on the input breakers and mains
breaker and make sure that every UPS is in
bypass mode.
7. Switch on the output breakers and main
output breaker, transfer the main maintenance
switch or static switch from "BPS" to "UPS".
8. Press the button on one UPS - all the UPSs will
turn on. The system will work in line mode.
How to remove a single UPS from a parallel system:
1. Firstly, a main maintenance mechanical switch
or static switch should be installed on the
parallel system.
2. Ensure the bypass is normal and the auto
bypass setting is at "enable," then press the
button to turn off the UPS system and the UPS
system will switch to bypass mode.
3. Transfer the main maintenance switch or static
switch from "UPS" to "BPS," then switch off
the output breakers, input breakers and mains
breaker in the parallel system. The UPS will
then shut down.
4. Switch off the main output breaker and output
breaker in the parallel system.
5. Remove the UPS of interest and disconnect
cables/wires.
6. Switch on the mains breaker and input breaker
of the reserve UPS, make sure the UPS is in
bypass mode.
7. Switch on the output breaker and main output
breaker.
8. Transfer the main maintenance switch or static
switch from "BPS" to "UPS" and press the
button to turn on the UPS, and the UPS will
turn on in line mode.
How to remove all the UPSs from a parallel system:
1. Firstly, a main maintenance mechanical switch
or static switch should be installed on the
parallel system.
2. Ensure the bypass is normal and the auto
bypass setting is set to "enable". Press the
button to turn off the UPS system, and the UPS
system will switch to bypass mode.
3. Transfer the main maintenance switch or static
switch from "UPS" to "BPS", then switch off the
output breakers, input breakers and mains
breaker in the parallel system, and the UPS will
shut down. The line will power the load via the
maintenance mechanical switch or static switch.
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