Vertiv Liebert EXL 31, Installer/User Manual

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1.4 Liebert® EXL S1 with a Third-Party UPS
The Liebert Load Bus Sync Controller synchronizes Liebert® EXL S1 UPS's with UPS systems made by another company. In
this scenario, the Liebert units must be configured as slave devices to follow the phase reference signal derived from the
non-Liebert master UPS. The Liebert units may be configured as parallel or single units, see Figure 1.5 on the next page.
NOTE: Configure all of the Liebert UPSs to follow the external synchronization signal by setting the main
synchronization source to external signal. If not set to follow the external synchronization signal, the UPSs will be in
phase with their own bypass line and will follow external synchronization only when the bypass line is out of
tolerance.
1 Liebert® Load Bus Sync Controller
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