Thomas & Betts 9395 - Manual (Page 59)

UPS 225 - 275 kVA
User’s and Installation Guide
1027212
Revision B 5
5.3.3 Starting the power module
To start the power module without transferring the critical load to normal, perform the following
procedure:
1. If the UPS contains input breaker CB1, verify that input breaker CB1 is open.
2. Close the UPS input feeder circuit breaker.
3. Close the UPS bypass input feeder circuit breaker.
4. Observe the UPS control panel becoming active, indicating logic power.
5. Press the CONTROLS pushbutton on the main menu bar. The System Controls screen appears.
6. On the System Controls screen, the power module (PM) status should indicate
SHUTDOWN.
7. If the UPS contains input breaker CB1, close input breaker CB1.
8. Press the pushbutton to display System Controls screen 2.
9. Press the PM ON pushbutton on the System Controls menu bar.
10. Observe the following messages appear sequentially on the power module (PM) status line:
DC STARTIN
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.
5.3.4 Transfer from normal to bypass mode
To transfer the critical load to Bypass mode, perform the following procedure:
CAUTION
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 Controls screen
appears.
2. Press the BYPASS pushbutton on the System Controls menu bar. The UPS transfers 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 Bypass mode and the BYPASS status indicator is illuminated.
The power module (PM) status indicates READY. The system is now on bypass and the UPS
power processor remains on.
WARNING
Power is present inside the UPS cabinets.