Intelligent Technologies (IT.) D77A I/O Module ProductsMN05002001E For more information visit: www.EatonElectrical.com 1IntroductionDescriptionCutler-Hammer ® Intelligent Technologies (IT.) D77A I/O Modules from Eaton Corporation® are part of the IT. family of products thatare best by design. These modules are designed and built for industrial applications with standard features including removablelocking terminal blocks and connectivity to IT. motor control. The size and features are a substantive engineering and marketing effort,involving extensive customer input. For more information on the IT. family of products, visit our website:www.EatonElectrical.comIT. D77A I/O discrete modules are available in 8 and 16 point densities, and in AC or DC voltage configurations. Input modules havetwo points per isolated common. Output modules are available in relay and solid-state configurations with two points per isolatedcommon.The IT. D77A I/O analog modules are available in variable voltage and current loop modules. Input modules support four analogchannels and output modules support two analog channels.D77A I/O products are designed for industrial applications, installed in a manner consistent with the guidelines outlined in thisdocument. They are designed for Pollution Degree 2 environments (clean and dry).Component CharacteristicsThis section identifies special features engineered into the Cutler-Hammer IT. D77A I/O modules.All ModulesThe IT. D77A I/O modules have the following common features:• LED Status — When the LED is illuminated the proper ON state signal is received at the input or at the output point.• Removable Lockable Terminals — Terminals are easily removable for I/O module replacement and are lockable so they will notvibrate loose. Terminals are available in screw type, cage clamp and insulation displacement.• Terminal Identification — Each terminal is marked for ease of wiring and troubleshooting.• Isolation — Each module is optically isolated between the field I/O and the backplane communication.• Securing Tabs — Each I/O module has a locking mechanism to secure it to the DIN rail.• Barrier Type Terminals — Each terminal has a barrier to minimize shorting of field wiring.Discrete Input ModulesThe IT. D77A Input modules have the following common feature:• Adjustable Debounce — Each point has adjustable debounce from 1 to 65 ms.• Sink/source — Each DC input module has back-to-back LEDs in the optical isolating circuit that can accept sinking or sourcingsignals.Discrete Output ModulesThe IT. D77A I/O Output modules have the following common features:• Configurable Safe State — Each output point has a loss of communication safe state setting.• Configurable Power ON State — Each output point has a power-up setting.