Product Description:

The CX1020-N031 expansion module is produced by Beckhoff and belongs to the CX Embedded PC Systems series. It attaches to a CX1020 CPU base unit to add dual serial channels for field devices such as barcode readers, variable-speed drives, or legacy PLCs. In an automation line, the module provides deterministic point-to-point communication between the embedded PC and peripheral equipment, assisting the control software in collecting data and issuing commands through differential serial signaling.

Each channel is presented on a 2 x 9-pin Sub-D plug and follows the RS422 / RS485 electrical standard, allowing either full-duplex or half-duplex transmission. The interface supports a maximum data rate of 115 kbaud, which is sufficient for configuration tasks, encoder feedback, or HMI text transfer. The module has two ports, so concurrent links can be maintained without additional hardware. Communication timing is derived internally, while line termination is selected with jumpers that assign pins 2 and 3 to data positive and pins 7 and 8 to data negative. Immunity to industrial noise is enhanced by compliance with EN 61000-6-2/EN 61000-6-4 EMC standards, so long cable runs remain stable.

The module draws logic power directly from the Internal PC104 bus, eliminating external cabling and reducing potential ground loops. A dedicated auxiliary pin provides a regulated +5 V supply for level converters or opto-isolated transceivers located in the adjoining cabinet. Housing and connectors fall under protection class IP20, so installation must occur inside a control enclosure that shields against finger contact and stray particles. Mechanical durability is verified against shock and vibration profiles in EN 60068-2-6/-27/-29, which permits mounting on rail-borne machines or compact processing cells. Signal pins 2, 3, 5, 6, 7, and 8 are used for data exchange and reference potential, while unused pins remain isolated to keep crosstalk low.