Product Description:

The CX2500-0031 is a plug-in communication module manufactured by Beckhoff for the CX Embedded PC Systems series. The module equips a CX controller with additional serial interfaces so that legacy drives, barcode scanners, or other field instruments using RS422 or RS485 signaling can be integrated into an automation network. By providing hardware level connectivity inside the embedded PC chassis, it frees DIN-rail space and allows deterministic, low-latency data exchange between the real-time control task and external equipment.

Two independent physical ports are presented on the front panel; the firmware recognizes them as 2 serial channels that share identical electrical characteristics. Each port uses a D-Sub socket with 9 pins, matching the mechanical layout of the PC-compatible COM interface. Signal transmission follows the RS422/RS485 differential standard, which enables multi-drop cabling and noise-immune communication up to the module’s ceiling of 115 kbit/s. Because the CX2500-0031 reserves a connector count of 2, wiring can be split between point-to-point and bus topologies without external repeaters. The module automatically drives its transceivers: Auto Receive and Auto Send are factory set to On, while Echo is set to Off, ensuring collision-free half-duplex exchange on two-wire networks.

Internally, the signal assignment follows the Beckhoff pin map so field technicians can use standard ribbon or molded cables. Protective ground is tied to Pin 5, and an auxiliary logic supply is available on Pin 6 (+5 V) for isolators or small sensors connected through the same header. Differential data pairs occupy Pins 2+3 / 7+8, allowing either one four-wire RS422 link or a two-wire RS485 link per port. For immediate network stability the built-in line termination is On, eliminating the need for external resistors at the controller end and simplifying cabinet wiring.