Promise Technology EX4650 Computer Hardware User Manual


 
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Appendix C: Battery Backup Unit
The Battery Backup Unit (BBU) maintains power to the cache on the SuperTrak
EX Controller card, when a power failure occurs to the Host PC. The failure could
be due to a problem with the PC’s power supply, a cessation of electrical service,
or an accidental disconnection of the power cable.
When power is interrupted, any data in the controller’s cache is lost. The BBU
maintains power to the cache so that any data stored there is saved until it can be
written to a physical drive.
The BBU is available as a kit, sold separately from the SuperTrak EX Controller
card.
The BBU kit includes the following components:
Battery Assembly – Includes a lithium battery and holder
Mounting screws (3)
Figure 1. BBU kit