Transfer From Normal To Bypass Mode - Powerware 9390 Installation & Operation Manual

9.4 Transfer from Normal to Bypass Mode

To transfer the critical load to bypass mode, perform the following procedure:
Powerware 9390 UPS (40–80 kVA) Installation and Operation Manual S 164201535 Rev A
®
8. Observe the following messages appear sequentially on the Power Module (PM)
status line:
DC STARTING
INVERTER STARTING
INVERTER SYNCING
READY
The rectifier and inverter turn on. When the inverter reaches full voltage,the UPS
is ready to transfer to the Normal mode and supply the critical load.
In Bypass Mode, the critical load is not protected from commercial power interruptions and
abnormalities.
1. Press the CONTROLS pushbutton on the Main menu bar. The System Control
screen appears.
2. Press the BYPASS pushbutton on the System Controls menu bar.
The UPS switches to Bypass mode and the critical load is immediately supplied by
the bypass source. If the bypass source is not available, the power processor
remains on and an alarm sounds.
3. The UPS is now operating in the bypass mode and the BYPASS status indicator is
illuminated.
The Power Module (PM) status indicates READY. System is now on bypass and
UPS power processor remains on.
Power is present inside the UPS cabinets.
UPS Operating Instructions
C A U T I O N
W A R N I N G
9-3