Vertiv Liebert MBSM - Dual Bus UPS Systems; Figure 6 Dual-Bus UPS Systems

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MBSM
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User Manual | 12
2.7 Dual Bus UPS Systems
Many modern solutions for critical loads power supply are designed following the dual-bus
architecture (see Figure 6).
This structure is composed basically by two UPS systems (N+N) supplied by two independent
power sources. The two systems outputs are connected to a number of static transfer switches
that provide the automatic selection of one of the two UPS sources to the critical loads.
The static transfer switch transient will not affect the critical load if the UPS sources are
synchronized.
Figure 6 Dual-bus UPS systems
Figure 7 illustrates the main synchronization function components from the system shown in
Figure 6.
Load 2
Load 1
STS 1
STS 2
Liebert
MSBM
Dual Bus
Gen
A
Gen
B
TRA TRB
UPS
System A
UPS
System B
Secure
Bus A
Secure
Bus B