Liebert 1000kVA manual Walk-In Display Screen, Walk-in display screen during start-up

Operation

3.2.4Walk-In Display Screen

From the module Master Menu, highlight WALK-IN DISPLAY and then press the Select pad. Note that this screen is displayed at the UPS modules but is not required at the System Control Cabinet (SCC).

Figure 21 Walk-in display screen during start-up

DOWN :		SELECT : MASTER MENU
SELECT :	© 1989-2003

D.C. VOLTS

INPUT AMPS

OUTPUT VOLTS

0% 25% 50% 75% 100%

The Walk-In Display screen enables the operator to monitor the UPS module DC bus voltage, the input currents and the output voltage. This is important during the start-up procedures.

During start-up, the UPS module input circuit breaker is closed and power is applied to the UPS mod- ule. The Walk-In Display screen graphically shows the voltage increasing on the DC bus as the UPS module rectifier begins to walk-in.

The DC Volts bar gradually moves to the right. After the DC Volts bar reaches the 90% level, the UPS module inverter starts-up and the Output Volts bar also moves to the right. Both the DC Volts and the Output Volts bars should settle near the 100% line as the UPS module becomes fully ener- gized.

The three Input Amps bars (one for each phase of input current) move to the right during the initial transformer inrush. They should return to the left after the momentary inrush has subsided, then increase to about 10% as the DC Volts increase.

Modules equipped with the optional input filter will indicate more than 10% with no connected load.

NOTE

After the critical load is transferred from the bypass line to the UPS modules, the Input Amps bars continue to indicate the percent of the design input current to the UPS module rectifier.

If any Input Amps bar differs from the average bar length by more than 10%, call Liebert Global Services.

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