Chapter 5 Operating Instructions 39
Liebert APM 90 Integrated Modular UPS User Manual
5.2.2
Start-Up Procedures (Into Battery Mode, Battery Cold Start)
1. Verify that the battery is properly connected.
2. If the number of the power module is less than four, you can press the battery start button (see Figure 5-2)
on the front panel of any power module. If more than four power modules, first press the battery start button
of any power module, and then wait for five seconds to press the battery start button of another power
module.
At this point, the LCD displays the start screen, and the battery indicator flashes green. It stops flashing and
becomes solid green about 30 seconds after the rectifiers enter normal operation.
Battery start button
Figure 5-2
Location of battery start button
Note
After step 2, if any of the following conditions occurs, open the BCB or confirm that the BCB has tripped automatically
and is open. The system can be started up one minute later.
EPO action
Fault in system commissioning
3. Press and hole the INVERTER ON key for two seconds, and the UPS operates in battery mode.
5.3
Procedures For Transfer Between Operation Modes
5.3.1
Transfer From Normal Mode To Battery Mode
Open the input switch to cut off the mains input, and the UPS enters battery mode. To return to normal mode,
wait a few seconds and close the input switch to connect the mains power to the UPS. The rectifiers will restart
automatically after 10 seconds and resume feeding power to the inverters.
5.3.2
Transfer From Normal Mode To Bypass Mode
Press and hold the INVERTER OFF key for two seconds to transfer the UPS to bypass mode.
Note
In bypass mode, the load is being powered by the mains input and is not receiving conditioned power through the
inverters.
5.3.3
Transfer From Bypass Mode To Normal Mode
In bypass mode, press and hold the INVERTER ON key for two seconds. When the inverters are ready, the UPS
transfers to normal mode.
5.3.4
Transfer From Normal Mode To Maintenance Mode
When the UPS is operating in normal mode, use the following procedures to transfer the load from the
inverter output to the maintenance bypass.