Mitsubishi AJ55TB32-4DT Digital Output Expansion Module for MELSEC-F FX Series

The Mitsubishi AJ55TB32-4DT (AJ55TB32-4DT) is a discontinued digital output expansion module designed for use with Mitsubishi Electric MELSEC-F FX series programmable logic controllers. Serving as an external expansion unit, this module provides expanded output capacity to control external actuators, indicators, and switching circuits across industrial machinery and automated manufacturing processes. It features 16 digital output channels equipped with normally open relay contacts, enabling reliable load switching and galvanic isolation between the controller logic and field devices. Designed as a functional equivalent to the FX16EYRESULBB unit, the module integrates seamlessly into existing MELSEC control systems to maintain machine operability and reduce downtime during retrofits or system repairs. As a legacy spare part, it allows facility engineers to replace worn or malfunctioning digital relay output units without requiring complete redesign of the PLC rack or control cabinet wiring. The robust relay contact design handles diverse automation tasks requiring dry-contact output switching in assembly lines, packaging equipment, and material handling systems.