Intelligent Technologies (IT.) D77A I/O Module ProductsMN05002001E For more information visit: www.EatonElectrical.com 5Dimensional DataFigure 2 illustrates the dimensional data of the IT. D77A I/O modules.Figure 2: Module Physical Dimensions, mm [in]a) Single Wide Moduleb) Double Wide ModuleNote: Ventilation requirements necessitate a minimum of 50 mm (2 in) on the top and bottom of each module and to each side of amodule grouping.Power RequirementsThe current draw for the IT. D77A I/O modules can be found in the module specification table for each specific module type. Whenspecifying the 24 volt DC power supply, the power rating must support the sum of all the modules’ current draw added to the systempower requirements.For more information on the sizing of power supplies, refer to the IT. QCPort System Install and Planning Guide (Publication No.MN05001002E).Surge SuppressionIT. D77A Discrete I/O output modules have built-in surge suppression (snubbers) to reduce the effects of transient voltages. Whenconnecting output devices that have inductive loads (e.g., solenoids, relays, motor starters, etc.) additional surge suppression isrecommended and should be added across the load. The addition of customer-supplied surge suppression for inductive loadsprolongs the D77A output life.a b90[3.5]45[1.8] 68[2.7]12[0.5]90[3.5]22.5[0.9]D77A-002
