Emerson 540VDC manual OFF Mode, Standby Mode, Startup Mode, UPS DC Bus Voltage = Vcharge

System Overview

5.3.1OFF Mode

When the Liebert FS is initially powered on, it enters the OFF mode and magnetically levitates its rotating group. A manual user command will make the system transition from OFF mode to STAR- TUP mode if all startup conditions are met.

NOTE

Startup conditions are:

•UPS DC bus voltage ≥ Vcharge and

•Status is “OK”.

The Liebert FS also will enter OFF mode at the end of a shutdown and will transition automatically from SHUTDOWN mode to OFF mode.

5.3.2STANDBY Mode

In STANDBY Mode, the Liebert FS will be ready for Startup but be in a STANDBY Mode waiting for user initiation of STARTUP Mode (State of Charge = 0%). By pressing the STARTUP button “F1” at that point the Liebert FS will automatically transition into STARTUP Mode.

Figure 46 STANDBY mode diagram
State of Charge < 0	State of Charge > 0

0%

UPS DC Bus Voltage = Vcharge

10
9	0
9
.
	%
5
%

The Liebert FS will be in STANDBY Mode as long as:

•Liebert FS’s SOC is less than 0%; and

•UPS DC Bus Voltage = Vcharge

•STARTUP has not been initiated

5.3.3STARTUP Mode

In STARTUP mode, the Liebert FS will charge (increase flywheel speed) up to the minimum operat- ing speed (State of Charge = 0%). At that point the Liebert FS will automatically transition into CHARGE mode.

Figure 47 Startup mode diagram
State of Charge < 0	State of Charge > 0

0%

Note: UPS DC Bus Voltage ≥ Vcharge

991 .00% 5%

The Liebert FS will be in STARTUP mode as long as:

•Liebert FS’s SOC is less than 0% and

•UPS DC Bus Voltage ≥ Vcharge.

NOTE

In STARTUP mode, the Liebert FS will not be capable of supporting the UPS DC bus.

In case the UPS DC bus voltage drops below Vcharge while in STARTUP mode, the Liebert FS will transition automatically into COAST mode. As soon as the UPS DC bus voltage rises above Vcharge, the Liebert FS automatically exits COAST mode and resumes STARTUP mode.

46	DISCONTINUED
	PRODUCT