Emerson GXT2-PP20KRT208 - Manual (Page 8)

System Description
4
2.0 S
YSTEM
D
ESCRIPTION
2.1 Compatibility
The Liebert GXT2-PP20KRT208 parallel POD is compatible only with the Liebert GXT2-10000RT208
UPS. No more than three Liebert GXT2-10000RT208 UPSs can be connected to the parallel POD.
2.2 Redundancy Design
During normal operation with parallel connection of three Liebert GXT2-10000RT208 UPSs, the par-
allel POD supplies 20kVA of output power plus redundancy of one 10kVA UPS. With the Liebert
GXT2-PP20KRT208 N+1 redundancy design, the failure of one UPS will not affect the functioning of
the overall system.
2.3 Maintenance Bypass
When the UPS system must be completely shut down, maintenance bypass allows the parallel POD to
work in the normal operation without interrupting power to the load. As shown in Figure 1, the Lie-
bert GXT2-PP20KRT208 provides an alternate path for utility power to the connected load. In the
event that the UPS experiences a failure, the UPS battery runs out or any other condition occurs
requiring maintenance on the UPS, the user may manually transfer the connected load from the
inverter to bypass by switching the maintenance bypass breaker to the On position.
Figure 1 Paralleling system block diagram
UPS1 UPS3
Output Breaker
Parallel Signal
Board
Optional POD
Load
Utility
Terminal Block
of POD
(Output)
O/P Breaker
UPS2
Output Breaker Output Breaker
Terminal Block
of POD
(Main Input )
Branch Breaker
Input Breaker Input Breaker Input Breaker