Liebert UPS System user manual Startup Procedure, Explanation of Circuit Breakers

Chapter 4 Commissioning of UPS

Chapter 4 Commissioning of UPS

4.1 Startup Procedure

4.1.1 Explanation of Circuit Breakers

From the layout of Figure 1-3 and Figure 1-4, the startup of UPS has connections with the following circuit breakers

Q1 : Connects rectifier to Utility source

Q2 : Connects bypass to Utility source

Q5 : Connects UPS output to the Load

Q3BP : Connects bypass input source to the load switch

QF1 : Battery Circuit Breaker

4.1.2 Startup

All the circuit breakers of the UPS should be switched off and phase rotation correct. The battery cables are connected correctly. Q1 and Q2 are connected to utility.

Note

Before startup, do not connect the load

The UPS should be started up according to the following procedures:

Step 1 : Switch on Q2 and Q5. The power source indicator on the panel turns on and the LCD displays information during startup.

Step 2 : Switch on Q1 and QF1. The sound of the relay closing should be heard. After 2 secs, the main contactor closes. The rectifier starts after the soft start relay opens. The rectifier indicator flashes several times and the rectifier enters normal operation states after about 10 secs.

Step 3 : The battery input contactor closes automatically after the DC bus reaches the pre-set value. The battery indicator illuminates before the battery contactor closes and it turns off after the contactor closes.

Step 4 : Press the button “inverter start” for two seconds. The inverter will start up and enters normal operating state when the inverter indicator flash.

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