Thomas & Betts 9395 - Manual (Page 58)

UPS 225 - 275 kVA
User’s and Installation Guide
1027212
Revision B
5
6. On the System Controls screen, the power module (PM) status should indicate
SHUTDOWN.
7. Close the battery breaker.
8. If the UPS contains input breaker CB1, close input breaker CB1.
9. Press the NORMAL pushbutton on the system controls menu bar.
If Auto Bypass is enabled (factory default), the critical load is immediately supplied by the
bypass source, in Bypass mode, until the inverter turns on and the UPS transfers to Normal
mode. The status indicator on the UPS control panel indicates the UPS is in Bypass mode.
If auto bypass is not enabled, the UPS output remains off until the UPS transfers to normal
mode.
10. Observe the following messages appear sequentially on the power module (PM) status line:
DC STARTING
INVERTER STARTING
INVERTER SYNCING
READY
ONLINE
The rectifier and inverter turn on. The inverter continues to ramp up to full voltage.
Once the inverter reaches full voltage, and the battery breaker is closed, the UPS output
contactor K3 closes and the static switch turns off. Power is now supplied to the Critical
load in Normal mode. It takes approximately 1 minute for the UPS to achieve Normal mode.
11. The UPS is now operating in Normal mode and the NORMAL status indicator is illuminated.
5.3.2 Starting the UPS in bypass mode
If the inverter output of the UPS is not available and the critical load needs to be energized,
perform the following procedure:
CAUTION
In Bypass mode, the critical load is not protected from commercial power interruptions and
abnormalities.
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 BYPASS pushbutton on the System Controls menu bar.
The critical load is immediately supplied by the bypass source, in Bypass mode.
9. The UPS is now operating in Bypass mode and the BYPASS status indicator is illuminated.