KL6401-0020 by Beckhoff

The KL6401-0020 LonWorks interface module is produced by Beckhoff for the KL Analog Input Modules series. It functions as a fieldbus coupler that transfers LonWorks network data to the internal K-bus, allowing a controller to read and write process variables in real time. The module occupies one terminal width on a DIN rail and connects distributed I/O, temperature sensors, and other analog endpoints to an industrial PC without requiring an external gateway. Its compact format allows it to be installed alongside other bus terminals within a control cabinet. The direct connection between the field network and the K-bus reduces the amount of separate interface equipment required in the enclosure.

The operating electronics receive power from the system bus at 24 VDC. Average K-bus current consumption is limited to 55 mA, allowing multiple terminals to share the same power segment without overloading the power supply. Each LonWorks packet is mirrored in the controller memory as a process image, with 36 bytes available for input data and the same capacity available for output data. A peak channel throughput of 78 kbytes allows the terminal to process rapidly changing analog variables without creating a communication bottleneck. Field-side communication follows the FTT-10/LPT transmission standard, supporting twisted-pair wiring at rates of up to 78 kbit/s. The interface also supports free-topology layouts commonly used in building automation networks.

The application image can contain up to 62 network variables, giving the CPU direct access to distributed measurements. The terminal also provides one output object for sending an actuator command through the network. Its housing snaps onto a 35 mm DIN mounting rail, allowing it to fit standard industrial control enclosures. The enclosure has an IP20 rating and is intended for installation in a protected control cabinet rather than an exposed machine area. The module supports enhanced mechanical loads for use where vibration or movement may affect cabinet-mounted equipment. Its variable installation position permits horizontal or vertical placement within densely packed enclosures while maintaining normal operation.