EL3144 by Beckhoff

The EL3144 is an analog input module manufactured by Beckhoff for the EL EtherCAT Terminals series. Intended for distributed control cabinets, the terminal converts four independent process currents into digital words that the EtherCAT master can read with cycle-accurate timing. By integrating signal conditioning, analog-to-digital conversion, and network communication in a compact housing, the device simplifies the collection of instrumentation data from pressure, level, or temperature sensors in industrial automation systems.

The module offers 4 single-ended channels that accept loop signals through a 2-wire connection, so power and measurement share the same pair commonly used by process transmitters. Each sample is quantized with 16-bit resolution, including the sign, and is acquired sequentially through the multiplexed architecture to prevent crosstalk among channels. A configurable hardware filter limits the analog bandwidth to 5 kHz, allowing unwanted high-frequency noise to be attenuated before conversion. The terminal supports distributed clocks, allowing phase-aligned sampling when multiple analog terminals operate in the same EtherCAT system. Each single-ended input is measured against a common internal ground. The enclosure meets the IP20 protection class, making it suitable for installation inside control cabinets that prevent direct access to live parts.

For electrical integrity, the input circuit has a dielectric strength of up to 30 V, helping protect the bus electronics from field-side voltage differences. The input stage tolerates a maximum continuous load of 40 mA without damage. The housing snaps onto a 35 mm DIN rail for installation with other EtherCAT terminals. Configuration handling uses the NoCoeStorage feature, allowing startup parameters to be supplied by the EtherCAT master when the terminal is initialized. In the process image, the module provides 4 x 16-bit + 4 x 8-bit entries, allocating separate areas for signed measurement values and status flags that the PLC can access during each EtherCAT cycle.