Appendix D: Uninterruptible Power Supply

D.5 Power On

When powering on the subsystem, the UPS must be powered on before the subsystem. For instruction on how to power on the UPS, please refer to the documentation that came with your UPS. Note that the power on sequence described in Chapter 4 will be altered. The power on sequence when a UPS is connected is shown below:

Step 1. Power on SCSI channel connection devices (including hubs and switches).

Step 2. Power on the UPS.

Step 3. Power on the subsystem.

Step 4. Power on the host computers.

Step 5. Trigger the firmware to allow the subsystem to detect the UPS. To see how to do this please, refer to the Generic Operation Manual that came with the subsystem.

NOTE:

•A UPS can be connected to the subsystem after the subsystem has been powered on, but you will have to trigger the firmware to allow the subsystem to detect the UPS.

•If you are daisy chaining systems together, be sure to make all the cable connections and then power on the A24F-G2224 subsystem that is not directly connected to host computer before powering on the first subsystem.

D.6 UPS Status Monitoring

If a UPS has been correctly connected to the subsystem, the status of the UPS will be constantly monitored by the controller through the COM2 (audio jack) serial port. The status of the UPS will determine the controller’s write policy, and messages that appear on the LCD panel and other monitoring devices will keep you informed of the UPS status.

D.6.1 Normal Operational Status

If the UPS has been connected to main power and the UPS battery power level is above 50%, then no status messages will appear and the default “Write Back” write policy will be implemented by the controller.

 

 

 

Power On

D-3