Allen-Bradley 1784-KT Communication Module

The Allen-Bradley 1784-KT Communication Module is a legacy ISA/EISA format interface card that lets a personal computer, workstation, or terminal communicate with Allen-Bradley processors and controllers. It serves as a bridge between host systems and AB automation hardware, supporting both direct connections and Data Highway Plus network communication to enable program transfer, monitoring, and data exchange with AB controllers. Sold as part of the 1784 family, the 1784-KT is commonly used in older control architectures where PC-based software must interface with AB hardware; operation typically requires compatible host-slot hardware and Rockwell-provided drivers. Because the card fits the ISA/EISA bus, it is installed in older IBM‑PC compatible systems and is now considered a discontinued component in Rockwell Automation’s catalog. Variants and documentation reference KT/B alongside the base KT family, reflecting a long-running lineage of interface functionality for legacy AB PLCs.