Emerson 540VDC manual Appendix F.3.2 Operating the Liebert FS Without Batteries

Auxiliary Backup AC Power Supply

Appendix F.3.2 Operating the Liebert FS Without Batteries

If the Liebert FS is operating without batteries, Liebert recommends feeding the backup AC power supply from a separate, protected supply. This may be the output of another UPS or a supply from a separate feeder circuit (see Figures 158 and 159).

Figure 158 Two Liebert FS units operating in a paralleled for capacity (not redundancy) configuration, with a UPS and without batteries attached to the DC bus

	Grid
	Supply
Fed from a
	BACKUP AC
protected AC
	POWER SUPPLY
supply, either
the output of
another UPS
or a separate
feeder supply

UPS

DC Bus

	UPS
	Output	Fed from a
BACKUP AC		protected AC
POWER SUPPLY		supply, either
		the output of
		another UPS
		or a separate
		feeder supply

Liebert FS Liebert FS

Figure 159 Multiple Liebert FS units operating with a UPS and without batteries attached to the DC bus

	UPS
Grid					UPS
Supply					Output
			Distribution
				panel*
		DC Bus

* NOTE:

Distribution panel allows3 Liebert FS Units removal of a Liebert FS without

disrupting the other units

152	DISCONTINUED
	PRODUCT