CX1020-N040 BECKHOFF System Interface Dual RS232 COM Port Module

Product Overview

The CX1020-N040 (CX1020N040) is a high-precision serial communication interface designed to expand the connectivity of the CX1020 Embedded PC series. This module adds two independent RS232 interfaces, designated as COM3 and COM4, through two standard 9-pin D-sub male connectors. It is an essential component for industrial automation systems that require simultaneous communication with legacy hardware, such as barcode scanners, weighing scales, operator terminals, or older PLC systems. Engineered for seamless integration into the modular CX controller architecture, the CX1020-N040 ensures reliable point-to-point data transmission while maintaining a slim 19 mm profile, allowing for dense control cabinet configurations without sacrificing computational power.

Technical Configuration

The CX1020-N040 hardware is optimized for high-speed serial data exchange, supporting a maximum baud rate of 115 kbaud per channel. The module utilizes the internal system bus for both data communication and power supply, drawing energy through the CX1100-xxxx series power supply modules. To ensure system stability and signal integrity, this interface follows strict configuration logic and is not combinable with the N031 or N041 interface options. Each RS232 port is physically implemented as a 9-pin D-sub plug, providing a mechanically secure connection suitable for high-vibration industrial environments. The fanless and compact design emphasizes long-term maintenance-free operation in demanding plant floor conditions.

Technical Specifications

Technical FAQs

How are the COM3 and COM4 ports addressed within the TwinCAT environment?

The CX1020-N040 is identified during the hardware scan in TwinCAT System Manager. The ports are automatically assigned as COM3 and COM4 in the operating system (Windows CE or Windows Embedded Standard). You can then use the Serial Communication library in TwinCAT to manage the data buffer and baud rate settings for each port independently.

Is it possible to power an external device through the D-sub pins?

No. The RS232 interface pins follow the standard signal-level conventions. Power for the module itself is drawn from the system bus via the CX1100 power supply, but the D-sub plugs do not provide power contacts for external peripheral devices.

What is the maximum cable length supported by these RS232 ports?

Per the RS232 standard and Beckhoff's industrial specifications, the maximum cable length should not exceed 15 meters to ensure data integrity at higher baud rates. For distances beyond this, using a serial-to-fiber or serial-to-Ethernet converter is recommended.

Engineering & Installation Guide

• Bus Interface Integrity: Before attaching the CX1020-N040 to the CX1020 CPU or an adjacent module, ensure the internal PC104-style connectors are free of dust and debris. The modules must be snapped together firmly until the locking mechanism engages to ensure a continuous power and data path across the system bus.

• Conflict Prevention: Verify that your system configuration does not include N031 or N041 modules. These modules share internal address resources; attempting to combine them will cause hardware initialization failures during the boot sequence.

• Shielding Requirements: In environments with high electromagnetic interference (EMI), use only high-quality shielded D-sub cables. The metal shell of the D-sub plug must be connected to the cable shield to provide a discharge path for noise, preventing data corruption on the COM3/COM4 lines.