ELX1052 by Beckhoff

The ELX1052 digital input module is built by Beckhoff as part of the EL EtherCAT Terminals series. It accepts intrinsically safe field signals and transmits them over the EtherCAT bus, enabling compact, panel-mounted I/O expansion in automated plants. By embedding explosion-zone sensor wiring into the standard DIN-rail terminal row, the module reduces remote junction boxes and speeds up commissioning in distributed control systems.

The terminal electronics draw power from the EtherCAT backplane at 24 V DC, so no auxiliary supply lines are required. It offers 2 intrinsically safe inputs that follow the 2-Wire NAMUR principle; each channel can therefore detect both current flow and lead integrity through the same conductors. A low-level current of <= 1.2 mA is interpreted as logic "0," while a drive of >= 2.1 mA registers as logic "1." These fixed thresholds let the PLC discriminate clear off and on states even when long sensor cables are used. Two blade/spring power contacts relay the supply across neighboring terminals, and wiring is performed by spring actuation with a screwdriver to shorten installation time and eliminate twisting of stranded cores.

In normal operation the terminal occupies only 12 x 100 x 68 mm, so several units can be arranged side by side on a 35 mm DIN rail (EN 60715) using the double slot and key profile without widening the control cabinet. The polycarbonate housing is rated IP20, providing finger protection in enclosed panels. Diagnostic functions compare the sensor loop against a cable-break limit of <= 200 µA and a short-circuit threshold of >= 6.3 mA, allowing the controller to flag wiring faults immediately. Continuous power bridging is maintained by the integrated blade contacts even when terminals are exchanged hot-plug.