Powerware 9395 UPS and Plus 1 UPS 650825 kVA - Manual (Page 137)

UNDERSTANDING UPS OPERATION
EATON Powerware ® 9395 UPS (650–825 kVA) Installation and Operation Manual S 164201725 Rev 2 www.powerware.com 6−25
Main Power Flow
UPS 1
UPS 2
UPS 3
UPS 4
Output to
Critical Load
Battery
UPS Input
Tie Cabinet
UPS 1 Output
Bypass Input
UPS 2 Output
UPS 3 Output
UPS 4 Output
Battery
Battery
Battery
Closed
Open
Breakers
Figure 6-20. Path of Current through the UPSs in Battery Mode – Distributed Bypass
If at any time during the battery discharge the input power becomes available again,
the rectifier begins to supply DC current to the inverter. At this point, the UPS returns
to Normal mode. If at any time during the battery discharge the AC input power
becomes available again, each rectifier turns on, assumes the inverter load from the
batteries, and begins recharging the batteries. Depending on the total load and the
duration of the battery discharge, battery and rectifier input current limit alarms may
be seen for a short time due to the current required to recharge the batteries.