Emerson 480V user manual UPS Startup, Startup Procedure, Indicator State

Operating Instructions

9.2UPS Startup

The Liebert NX must be fully installed and commissioned before startup, and external power isolators must be closed. Once those general conditions are met, the UPS may be started.

9.2.1Startup Procedure

To start the UPS from a fully powered-down condition:

1. Open the UPS door to gain access to the main input circuit breakers.

! WARNING

During this procedure the output terminals will become live.

If any load equipment is connected to the UPS output terminals, please check with the load user and ascertain whether it is safe to apply power to the load. If the load is not ready to receive power, then ensure that it is safely isolated from the UPS output terminals.

2.Close CB1, CB2 and CB3 (CB5 is open).

The main input contactor closes automatically and the LCD begins to show start-up

screens. The Rectifier indicator flashes green while the rectifier is starting up. It stops flashing and becomes solid green about 30 seconds after the rectifier enters the normal operation state.

After initialization, the bypass SCR closes. Because the output circuit breaker is still open, the UPS channels power through the Maintenance Bypass Supply line (CB3). The bypass indicator extinguishes, provided that the bypass is normal.

The opening display is shown in the figure at right. The UPS Mimic display indicators will be:

Indicator	State
Rectifier indicator	Green
Battery indicator	Red
Bypass indicator	Off
Inverter indicator	Off
Output indicator	Off
Status indicator	Off

F1 F2 F3 F4 HELP

3.Close CB5 (CB1, CB2, CB3 and CB5 are closed).

The Maintenance Bypass supply is now in parallel with the UPS Static Switch supply.

4.Verify that the Bypass indicator is Green, then open CB3.

The UPS powers from static bypass instead of from maintenance bypass. The bypass and load indicators turn on. The design of the hardware and software ensures uninterrupted output.

5.Close external battery circuit breaker.

After the UPS detects that the battery is connected, the red battery indicator extinguishes moments after the battery charger starts operation.

The UPS Mimic display indicators will be

Indicator	State
Rectifier indicator	Green
Battery indicator	Off
Bypass indicator	Green
Inverter indicator	Off
Output indicator	Green
Status indicator	Amber

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