Data Power Solutions Quick Start GuideCopyright © 2006-2009 Eaton Corporation. All Rights Reserved.10640205 February 2009 19Step 5 – Arrange sleeves and tighten clamp screws• Arrange the sleeves so that they are all within 10mm (3/8”) of the terminals.• Tighten all cable clamp screws. Required torque: 1.5 – 2Nm (13.2 – 17.7 lb-in). Tighten the screws of any unused clamps to prevent access to the dc output terminations.Installing the External Batteries (if applicable)This section applies to APS3-059, APS3-061 and APS6-059 dc power systems only.One 48V battery string can be connected to APS3-059 and APS3-061, and up to three 48Vbattery strings to APS6-059 dc power systems. A 48V battery string consists of either 24 ValveRegulated Lead Acid (VRLA) 2 V cells or four VRLA 12 V monoblocs.Because of the wide range of battery types and sizes available, we do not supply batterieswith the above mentioned power systems and therefore do not cover battery installation inthis guide. Always install batteries according to the relevant battery manufacturer’sinstructions.Battery SizingBattery manufacturers provide various types of information for sizing batteries such asconstant current discharge and constant power discharge data. Your battery supplier will beable to assist you with sizing the battery for your application. Before a battery can be sized,the following information is required.Required backup time, minimum cell voltage (typically 1.83V/cell), load power & operatingtemperatureIn data applications most loads are constant power for a specified backup time. Therefore, forsizing a battery for the required backup time, constant power discharge data should be used.Batteries for use in North America must be a UL recognized type, category BAZR2.Battery LocationValve Regulated Lead Acid (VRLA) batteries emit very small amounts of hydrogen gas intothe surrounding atmosphere under normal float charging conditions. For that reasonbatteries should never be installed in a sealed enclosure or cabinet. Install the batteries in awell-ventilated location to prevent accumulation of hydrogen gas to flammable or explosivelevels.Building air conditioning and ventilation systems already in place for optimum equipmentoperation and comfort of personnel usually meet or exceed VRLA battery ventilationrequirements. For specific battery ventilation requirements, always refer to the batterymanufacturer’s installation instructions. Avoid:• Installing the batteries next to any heating source or under air ducts.• Exposing part of a battery string to direct sunlight.• Any other locations that would cause temperature variations within the batteries.