Liebert NX UPS System user manual UPS Startup, Start-Up Procedure, Indicator State

Operating Procedures

6.2UPS Startup

The 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.

6.2.1Start-Up Procedure

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

1. Open the UPS door to gain access to the main power switches.

!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.

!CAUTION

Do not operate the rotary switch too fast. Always wait at least 30 seconds when rotating the switch from one position to another

2.Close CB1.

3.Turn the rotary switch to TEST.

The bypass static SCR (M2) 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 static switch closes.

Because output switch SW1-A is still open, the UPS channels power through Maintenance Bypass Supply line (SW1-D). The bypass indicator extinguishes, provided that the bypass is normal. The UPS mimic display indicators will be:

Indicator	State
Rectifier indicator	Off
Battery indicator	Off
Bypass indicator	Off
Inverter indicator	Off
Load indicator	Off
Status indicator	Off

! WARNING

Do NOT turn the rotary switch until the rectifier indicator stops flashing green. 4. Turn the rotary switch to BYPASS.

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

The maintenance switch SW1-D opens and output switch SW1-A closes. The UPS powers from static bypass instead of from maintenance bypass. The bypass and load indicators turn on. The design of the rotary switch ensures uninterrupted output.

46