Battery Backup Unit Option

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

 

 

 

 

Manual No. 775012

A-5