EL4028 by Beckhoff

The EL4028 is an analog output terminal produced by Beckhoff in the EL EtherCAT Terminals series. Designed for EtherCAT networks, the terminal converts digital setpoints from the controller into standardized voltage levels, enabling precise actuation of drives, positioning hardware, or process instrumentation within an automation cell. Its compact housing supports dense panel layouts while following the plug-together wiring approach that characterizes the company's I/O family.

Each module delivers 8 analog outputs, and every channel is converted with a 12-bit resolution, allowing fine voltage steps suitable for proportional control loops. In the EtherCAT process image, the terminal appears as an 8 × 16-bit process image, so the controller exchanges two bytes per channel during every cycle. Output circuitry is referenced to a single-ended ground, simplifying wiring when sensors and actuators share a common return. The channels are updated sequentially by multiplex sampling, which reduces crosstalk while sustaining deterministic timing. Nominal field supply is 24 V DC, delivered through the power contacts, allowing the EL4028 to source voltages for analog drives or valve amplifiers without external signal conditioners.

Support for Distributed Clocks enables sub-microsecond synchronization across all EtherCAT devices, keeping output waveforms aligned with motion or measurement tasks. The electronics draw their logic power from the E-Bus, eliminating separate wiring when the terminal is inserted into an existing slice. The housing locks onto a 35 mm mounting rail, and the terminal can be oriented in any position to accommodate cramped cabinets or rotating arms. An IP20 protection class guards the circuitry against solid objects, and the enhanced mechanical load rating provides resistance to shock and vibration in machine-level installations.