Beckhoff CX8031 CX8000 Series Embedded PC with PROFIBUS Slave

Description

Designed to bridge high-speed local control with legacy fieldbus networks, the Beckhoff CX8031 is a highly compact, DIN-rail-mounted Embedded PC equipped with an integrated PROFIBUS DP slave interface. This controller is engineered to process local automation logic independently while maintaining direct, deterministic communication with a master PROFIBUS system. Powered by an ARM9 400 MHz processor, the unit runs Windows Embedded CE 6 and is optimized for the TwinCAT 2 programming environment, allowing for rapid execution of PLC applications directly at the machine or field level.

Features

• Integrated Fieldbus Interface: Features a dedicated 9-pin D-sub PROFIBUS DP slave socket with robust electrical shielding.
• Dual Bus Support: Offers automatic recognition and direct connection of both E-bus (EtherCAT Terminals) and K-bus (standard Bus Terminals) for flexible I/O configurations.
• Persistent Data Security: Built-in 1-second UPS ensures up to 1 MB of critical persistent variables are saved to flash memory in the event of a power interruption.
• Highly Efficient Architecture: Consumes a maximum of 3 W, reducing thermal dissipation inside sealed industrial enclosures.
• Hazardous Location Certification: Fully approved for demanding environments with ATEX, IECEx, and cFMus Class I Division 2 ratings.

Applications

• Decentralized control stations interfacing with main Siemens, Beckhoff, or third-party PROFIBUS masters.
• Sub-assembly machine control requiring localized logic handling and high-density terminal options.
• Ex Zone 2 hazardous areas across chemical, petrochemical, and oil and gas processing facilities.
• Infrastructure control projects with space-restricted control panels requiring native EtherCAT or Bus Terminal expansion.

Technical Specifications Table

Connections and Interfaces

Empirical Engineering Insights

Alternative Models & Compatibility

The CX8031 is specifically tailored for TwinCAT 2 environments and is not compatible with TwinCAT 3 runtimes due to its underlying ARM9 hardware architecture. For applications requiring TwinCAT 3 compatibility or modern multi-core processing, developers should specify the CX8100 or CX8200 series controllers. Note that when migrating from K-bus (standard bus terminals) to E-bus (EtherCAT) on the same CX8031, the unit will automatically redetect the physical backplane bus topology on power-up without manual dip-switch changes.

Application Pitfalls & Engineering Notes

While the CX8031 provides up to 2 A of current directly to the E-bus/K-bus backplane, system integrators must compute the total current draw of all connected I/O terminals. Exceeding this limit will trigger a system shutdown or cause unstable communication anomalies. When deploying high-density terminal setups, plan for an intermediate power feed module, such as the EL9410, to inject supplementary bus power.

Commissioning & Wiring Tips

The PROFIBUS node address is manually configured using the physical address rotary switches positioned behind the front flap. Changes made to these rotary dials do not update in real-time; the CX8031 must undergo a full cold reboot (power-cycle) to register the newly assigned hardware address. Ensure that the shielding on the 9-pin D-sub PROFIBUS cable is grounded at both ends to eliminate industrial high-frequency electromagnetic interference.

Installation Guidelines