1. Battery Transparent Learn Cycle
A transparent learn cycle is a periodic operation that calculates the charge that is remaining in the battery to ensure there is sufficient energy. The operation runs automatically, and causes no impact to the system or controller performance.
The controller automatically performs the Transparent Learn Cycle (TLC) on the battery to calibrate and gauge its charge capacity once every 90 days. The operation can be performed manually, if required.
All PERC 8 (H310 - H710) and above have this feature.
2. Battery Learn Cycle
The time frame for completion of a learn cycle is a function of the battery charge capacity and the discharge/charge currents used. The expected time frame for completion of a learn cycle is approximately seven hours and consists of the following parts:
Learn cycle discharge cycle: approximately three hours
Learn cycle charge cycle: approximately four hours
Learn cycles shorten as the battery capacity deteriorates over time.
Note: In PERC H700 and previous, virtuals disks automatically switch to Write-Through mode when the battery charge is low because of a learn cycle. Once the battery charge is sufficient, Write-Back mode will be re-enabled.
During the discharge phase of a learn cycle, the battery charger is disabled and remains disabled until the battery is discharged. After the battery is discharged, the charger is re-enabled.
When the learn cycle detects the battery can no longer store enough charge for 24 hours you will receive a "Predicted failure" message in the system logs, telling you the battery is near the end of it's useful life and needs to be replaced.