Testing Battery Capacitywww.3ware.com 187Testing Battery CapacityBatteries in the BBU need to be replaced periodically. A battery test should berun every four weeks in order to get a reliable estimate of battery capacity, andto determine when it needs to be replaced.The battery test is used to measure the battery’s capacity to back up write data.In order to make a reliable estimate of battery capacity, the BBU pre-chargesthe battery before it proceeds with a full discharge cycle. The battery isautomatically charged again after the test completes. The whole processusually takes between 8 and 12 hours.While running the battery test and until charging is completed, write cache istemporarily disabled.For how to replace the battery, see the installation guide that came with yourcontroller.To test the battery in a BBU in 3DM 21 On the menu bar, choose Monitor > Battery Backup.2 On the Battery Backup page, click the Test Battery Capacity link.Figure 86. Battery Backup Information Screen in 3DM3 When a message cautions you that testing the battery will disable theBBU for up to 24 hours, click OK to continue.After the battery test starts, you will see the voltage start dropping;eventually the battery voltage will say "LOW". This is part of the batterytest. After the voltage drops to a point, it will start charging again, and thestatus will change to “Charging.” Eventually, the battery voltage will say“OK” again.
