The Beckhoff Fieldbus Box with PLC functionality is an intelligent fieldbus module for the decentralised pre-processing of I/O signals. This is a way of removing parts of the application out of the central control system to relieve the CPU and the fieldbus. Decentralised counting, control or switching are typical applications for the Fieldbus Box with integrated small controller. The reaction times are independent of the bus communication and of the supervising controller. In the event of a bus or controller failure, maintenance of function (e.g. bringing the process to a safe state in an orderly manner) is possible.

Almost unlimited I/O application possibilities result from the extendable Coupler Box with PLC functionality and IP-Link. Up to 120 extension modules, with 960 I/Os, can be directly addressed from the PLC program. The programmable PLC Box modules are therefore particularly suitable as autonomous small PLCs for the control of parts of a plant or of small machines.

Programming is carried out with TwinCAT in accordance with IEC 61131-3, using the same programming environment as for the TwinCAT PC control system. Five different manufacturer independent programming languages are available: Instruction List (IL), Function Block Diagram (FBD), Ladder Diagram (LD), Sequential Function Chart (SFC) and the high-level language Structured Text (ST). The program download occurs either via the fieldbus or via the programming interface. Extensive debugging functions (breakpoint, single step, monitoring, etc.) are also available.

The Fieldbus Box series with PLC functionality uses a powerful 16 bit controller, 32/96 kbyte program memory and 32/64 kbyte data memory. A further 512 bytes of non-volatile memory are available for remanent flags.

IEC 61131-3 TwinCAT programming environment
Programming interface

Programming interface under hinged inspection window

Signal type overview: ILxxxx-Cxxx
Digital I/O
Combi Ø 8 M8 M12
24 V DC 8-channel
4 input + 4 output
filter 3,0 ms, Imax = 0,5 A
IL2300-Cxxx IL2301-Cxxx IL2302-Cxxx