May 2001System Hardware Manual 2 - 29A6-324000-642-01 – Release 4.0May 20014.7.2 Memory BackupA backup battery is equipped on several of the ETU’s. Thisbattery retains the system’s memory in the event of anextended mains power failure where the system backupbatteries have also expired or where the ETU has beenremoved from the system.Table 2-11 External Backup Battery RequirementsBatteryCapacity (Ah)Backup DurationXen Axis(Max. 1.0A, 230W)Xen Master1 Cabinet(Max. 1.3A, 320W)Xen Master2 CabinetS(Max. 2.0A, 460W)Xen Master3 Cabinets(Max. 2.9A, 690W)1 hour 4.0 5.2 6.8 8.82 hours 8.0 10.4 13.5 17.63 hours 12.0 15.6 20.3 26.44 hours 16.0 20.8 27.0 35.25 hours 20.0 26.0 33.8 43.96 hours 24.0 31.2 40.6 52.77 hours 28.0 26.4 47.3 61.58 hours 32.0 41.6 54.1 70.39 hours 36.0 46.8 60.8 79.110 hours 40.0 52.0 67.6 87.9Note 1: The system requires a 24Vdc battery feed and so two 12 Vdc batteries for the quoted capacitywill be required.Note 2: The figures are based on a fully located system operating throughout the power loss. Backupdurations for an idle system will be approximately twice the quoted figures.Note 3: Use only Sealed Lead Acid type batteries and always install batteries in accordance with therelevant regulations.Table 2-12 ETU Battery Backup SpecificationsETU BatterySpecifications Quantity Approx.Backup TimeReplacementTimeCPUB( )-U13 ETU 3.7V, 60mAH Ni-Cd 1 21 days 2 YearsMBD-U13 UNIT 3.7V, 60mAH Ni-Cd 1 21 days 2 YearsMIFM-U13 ETU 3.7V, 60mAH Ni-Cd 1 21 days 2 YearsMIFA-U13 ETU 3.7V, 60mAH Ni-Cd 1 21 days 2 Years
