Vertiv Tech EXS 0080kTK16FN01000, Руководство пользователя

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Vertiv | Liebert EXS 80kVA UPS | User Manual 61
UPS Operating Instructions
5.3.4. Transfer from Normal Mode to Maintenance Bypass Mode
When the UPS is running in Normal mode, you can use this procedure to transfer the load from inverter output
to maintenance bypass.
Caution: Power Supply Interruption Danger of the Load
Before performing this procedure, check the LCD information first, and ensure that the bypass is normal and synchronized
with the inverter. Failure to do so may result in a brief interruption in the power supply to the load.
1. In Inverter mode, press the power button to transfer the load to maintenance bypass mode, and the inverter
will shut down.
2. If the UPS runs in single module mode, open the cabinet front door and remove fixing screws of the
maintenance bypass switch baffle, rotate the baffle to the left until it is in locked position, then fasten the
fixing screws. Now, the LCD displays ‘Maint. Switch Closed’.
3. Close the maintenance bypass switch Q3. Now, the maintenance bypass parallels with the UPS bypass.
4. Unplugging the EPO terminal disconnects the output switch Q5, main input switch Q1, bypass input switch
Q2. All the internal power supply is OFF now and the LCD no longer displays, and the maintenance bypass
powers the load normally.
Caution
When the UPS is in maintenance bypass mode, the load is not protected against abnormalities in the mains power supply.
• In maintenance mode, the load is directly fed by the mains power instead of the pure AC power from
the inverter.
Warning
1. If the maintenance is required, wait 10 minutes for the internal DC bus capacitance discharging.
2. The parts of UPS circuits also have hazardous voltage, though the rectifier input switch, bypass input switch and
battery switch are disconnected. UPS maintenance is therefore only applicable to qualified personnel.