EL1819 by Beckhoff

The EL1819 is a digital input module produced by Beckhoff within the EL EtherCAT Terminals series. Designed for distributed control cabinets, the terminal accepts field signals and forwards their states onto the EtherCAT ring so a PLC can monitor machine sensors in real time. Its compact design provides a high channel count in a format optimized for dense industrial automation systems. The terminal can collect signals from switches, proximity sensors, and other digital field devices used throughout automated machinery.

It operates from a control voltage of 24 VDC, and each channel draws only 3 mA, so large sensor banks can be powered without overloading the supply. An internal filter of 10 µs suppresses contact bounce before the states are sampled, and the inputs meet the electrical thresholds established for EN 61131-2 Type 1/3 devices. The terminal provides 16 inputs, and their logical states appear in the controller's process image as 16 input bits. Connections are made with a direct plug-in push-in clamp that supports a 1-wire topology, allowing signal conductors to be inserted without tools while maintaining individual channel isolation. All field returns share the 0 V power contact, which also serves as the reference ground.

The internal electronics typically draw 100 mA from the EtherCAT E-bus, removing the need for separate auxiliary wiring. The module mounts on a standard 35 mm DIN rail, and its 12 mm housing width keeps cabinet space requirements low when multiple terminals are installed together. With a protection rating of IP20, the module is intended for installation inside a suitable enclosure. Its installation position is variable, allowing horizontal or vertical mounting to suit the panel layout. The direct plug-in clamps remain accessible from the front even when adjacent terminals are installed closely together.