ABB HiPerGuard MV UPS User Manual page 75

75
Step User Action
User selects "Precharge" screen on GDM and presses
1
"Precharge" button
2
The User shall confirm that the battery voltage and the
DC bus voltage, as displayed on GDM screen, are
3
matching. Then the User shall close the battery circuit
breaker.
4
The User acknowledges that precharge is complete.
5
The system is now ready to start.
—
Table 8.01: DC bus
precharging steps.
—
Note: Pre-charge
1
can only be achieved
via GDM.
After the "precharge" is done, system is still in bypass and the battery strings are now connected and charged.
—
Figure 8.04: System
after "Precharge"
process of the DC
bus is complete.
1
System Response
MV UPS performs self-check. The float charger
will precharge the inverter DC bus at a con-
trolled rate.
GDM will indicate that battery voltage and DC
bus voltage now match. GDM will indicate "Pre-
charge Achieved".