Acer PCI to Ultra SCSI RAID Controllers DAC960PG - Manual (Page 37)

Battery Backup Unit Option
Manual No. 775012 A-5
Operation
Battery Conditioning Prior to Use
Battery conditioning is automatic. There are no manual procedures for
battery conditioning or preconditioning to be performed by the user.
Set-up – Enabling the Write-Back Cache
The write-back cache is enabled by toggling the write-back/write-through
mode switch. The write-back/write-through mode switch is accessed in the
Onboard Configuration Utility, RAID EzAssist, or in GAM. Refer to the
RAID EzAssist Configuration Utility User Reference Guide or the Global
Array Manager Client Software Installation Guide and User Manual for
instructions on how to examine and change the mode switch.
Battery Backup Capacity
Battery backup capacity is defined as the maximum duration of a power
failure for which data in the cache can be maintained by the battery. The
BBU’s backup capacity varies with the memory configuration installed on
the DAC960PG or DAC960PJ. Battery backup capacity can be reasonably
expected according to Table A-1
Table A-1. BBU Capacity vs. Cache Memory Configuration
Capacity Mem Type Battery Backup Duration
Typical Minimum
4 MB EDO ECC RAM 72 hours 40 hours
8 MB EDO ECC RAM 40 hours 20 hours
16 MB EDO ECC RAM 68 hours 28 hours
32 MB EDO ECC RAM 30 hours 14 hours
64 MB EDO ECC RAM 35 hours 23 hours
128 MB EDO ECC RAM 20 hours 12 hours