Beckhoff BK5151 Bus Coupler CANopen Compact Module

Description

Integrating standard K-bus I/O terminals into high-speed CANopen fieldbus networks, the Beckhoff BK5151 offers a compact, cost-efficient interface solution. This unit acts as a gateway, mapping standard terminal signal channels to the CANopen communication layer and process image. The complete Beckhoff BK5151 system supports automatic baud rate configuration and diagnostic feedback, ensuring seamless integration into distributed control systems.

Features

• Flexible Expansion: Connects up to 64 local Bus Terminals, with support for up to 255 terminals via K-bus extension units.
• High-Speed Communication: Automatic baud rate detection supports transmission speeds reaching up to 1 Mbaud.
• Robust K-Bus Power Supply: Generates up to 1750 mA of current output for internal electronics of connected terminals.
• Rich CANopen Services: Fully supports emergency objects, variable mapping, Node Guarding, Life Guarding, and store/restore options.
• Configurable Transfer Modes: Supports synchronous, cyclic, event-driven, and polling-based PDO modes.

Applications

• Decentralized factory automation and plant control systems.
• Hazardous environments requiring ATEX and IECEx Zone 2 intrinsic safety ratings.
• Material handling and machine building environments using centralized CANopen masters.

Technical Specifications

Empirical Engineering Insights

Alternative Models & Compatibility

The BK5151 replaces older BK5120 couplers in typical architectures. However, configure your software environments carefully: any hardware modifications or firmware transitions from standard BK series to the compact "BK5151" require an updated EDS (Electronic Datasheet) file imported directly into your CANopen master configuration utility to correctly register the updated device ID and dynamic mapping options.

Application Pitfalls & Engineering Notes

When sizing your system, calculate the total current consumption of the connected K-bus terminals. Although the integrated power unit outputs 1750 mA, exceeding this threshold will trigger a K-bus undervoltage alarm, interrupting communication. If your I/O array draws higher currents, insert a PE2001 power feed terminal downstream on the rail to supply supplemental voltage.

Commissioning & Wiring Tips

Always ensure that both physical ends of the CANopen network bus segment are terminated with a standard 120-Ohm resistor connected between CAN-H (pin 7) and CAN-L (pin 2). Omission of physical termination is a primary cause of packet collisions, CRC errors, and intermittent bus-off states. Use only double-shielded twisted pair copper media for field connections.

Installation Guidelines