UPS Operating Instructions
10.2 Multiple Module Parallel Operation
10.2.1 Starting the Parallel System in Normal Mode
To start the parallel system, perform the following procedure:
1.Close all uninterruptible power module input feeder circuit breakers.
2.If the UPMs are dual feed, close all UPM Bypass input feeder circuit breakers.
3.Observe all UPM control panel displays becoming active, indicating logic power.
4.Press the CONTROLS pushbutton on the main menu bar of any UPM. The System Controls screen appears on each UPM.
5.On the System Controls screen of each UPM, the power module (PM) status should indicate SHUTDOWN.
6.Press the NORMAL pushbutton on the System Controls menu bar of any UPM.
If Auto Bypass is enabled, the critical load is immediately supplied by the bypass source, in Bypass mode, until the inverters turn on and the UPMs transfer to Normal mode. The status indicator on each UPM control panel indicates the UPM is in Bypass mode. If Auto Bypass is not enabled, the UPM outputs remain off until the UPMs transfer to Normal mode.
7.Observe the following messages appear sequentially on the power module (PM) status line of each UPM:
DC STARTING INVERTER STARTING INVERTER SYNCING READY
ONLINE
The rectifier and inverter turn on. The inverter continues to ramp up to full voltage.
8.Close the battery breakers for each UPM any time after INVERTER SYNCING or CLOSE BATTERY appears on the display.
Once the inverter reaches full voltage, and the battery breaker is closed, each UPM output contactor K3 closes and each static switch turns off. Power is now supplied to the critical load in Normal mode. It takes approximately 1 minute for the UPMs to achieve Normal mode.
9.The UPMs are now operating in Normal mode and the NORMAL status indicator on each UPM is illuminated.
