Eaton 93E UPS 15-80 kVA (380/400/415 V)
Installation and Operation Manual
© Eaton Corporation plc 2015. All rights reserved.
Revision: 001
Document ID: 614-01975-00
79 (133)
Figure 32.Path of current through the UPS in standard battery mode
A
Static switch
1
Bypass input
Main power flow
B
Rectifier
2
Rectifier input
Energized
C
Inverter
3
Output
De-energized
D
Battery
converter
4
Battery
breaker
Closed
E
Battery
K1
Rectifier input
relay
Open
K3
Output relay
K5
Backfeed
contactor
During a utility power failure, the rectifier no longer has an AC utility
source from which to supply the DC output voltage required to support
the inverter. The rectifier input relay opens and the battery
instantaneously supplies energy to the battery converter. The converter
boosts the voltage so that the inverter can support the customer's load
without interruption. If the bypass source is common with the rectifier
input and detected not being available, the backfeed protection contactor
also opens. The opening of the input and the backfeed protection