ELX3152 by Beckhoff

The ELX3152 is an EtherCAT I/O terminal produced by Beckhoff within the EL EtherCAT Terminals series. Intended for distributed control cabinets, the unit snaps onto a DIN rail and forwards process signals to the EtherCAT bus while maintaining galvanic separation between field equipment and the PLC. Its compact housing and integrated energy-limiting features support data acquisition from hazardous-area instrumentation without requiring excessive cabinet space. The terminal is designed for process automation systems that need reliable communication between intrinsically safe field circuits and an EtherCAT control network.

The terminal operates from a system supply of 24 VDC, delivered through a SELV/PELV power feed on the backplane. Each input loop uses a dedicated channel supply, which confines the available energy to the individual circuit and prevents one channel from powering another. The external sensor supply is prohibited, preventing power from being introduced in a way that could exceed the permitted intrinsic-safety limits. The input electronics also have a fault threshold of 60 V; if a higher potential appears, the affected channel disconnects to protect downstream equipment. This arrangement allows the terminal to power compatible two-wire transmitters directly while keeping the field circuits electrically isolated from the control system. Separate channel operation also helps contain wiring faults within the affected input loop.

The field side uses Ex i protection, which limits the electrical and thermal energy available at the terminals to reduce the risk of ignition under approved operating conditions. The internal spring-cage connections follow the reinforced construction requirements of Ex e, providing secure conductor termination within the installation. An enclosure with an IP54 rating resists limited dust ingress and splashed water when the terminal is installed in the appropriate cabinet. Approved placement includes cabinets in a Zone 2 or non-hazardous area, and only compatible intrinsically safe field devices may be connected to the input channels. Proper separation, grounding, and cabinet installation remain necessary to maintain the intended protection method. The terminal can collect analog process data from hazardous-area sensors while communicating with the controller through the standard EtherCAT backplane.