The Beckhoff EJ EtherCAT Plug-ins series is a modular plug-in I/O system designed for direct integration on a signal distribution board, combining EtherCAT communication with application-specific function modules in a compact format.
The series includes couplers, digital I/O modules, motion-control modules for stepper and servo drives, and TwinSAFE plug-in modules for fail-safe digital inputs and outputs, allowing a single platform to cover standard control and safety tasks. These plug-ins are installed with defined mechanical and color coding, support structured power distribution and potential grouping, and can be extended with placeholder modules or linked to additional EtherCAT terminals and box modules. The system is intended for machine-oriented designs in which the electronics are integrated closely with a custom backplane or PCB layout rather than mounted as separate DIN-rail terminals. Overall, the EJ series is built for compact EtherCAT-based control architectures that need scalable module selection, PCB-level integration, and support for standard I/O, motion, and safety functions.
