BC4000 - Introduction

The Bus Terminal Controllers are Bus Couplers with integrated PLC functions. The BC4000 has a fieldbus interface for the Interbus system. It can be used as a decentralized intelligence in the Interbus system. The Interbus has a ring structure, and up to 512 stations can be operated in one ring. Data is transferred at 500 kbaud.

The Bus Terminal Controllers are intelligent devices. One unit consists of a Bus Terminal Controller, a number of terminals between 1 and 64 and a bus end terminal. The Bus Terminal Controller is programmed using the TwinCAT PLC Control programming system in accordance with IEC 61131-3. The configuration and programming interface on the BC4000 is used to load the PLC program.

The Bus Terminal Controller recognizes the terminals to which it is connected to and performs the assignment of the inputs and outputs to the words of the process image automatically. The first input/output signal will be added to the first bit of a word (LSB), beginning from the left. The Bus Terminal Controller adds further signals to the word. A clear separation is maintained between inputs and outputs. If the number of inputs or outputs is greater than 16 bits, the Bus Terminal Controller automatically begins a new word.

Since 1987 Interbus has become established as an open fieldbus system. The Interbus has a ring structure, and up to 256 stations can be operated in one ring. Data is transferred at 500 kbaud. The efficient data transfer allows sensor and actuator data to be transmitted quickly over large distances safe from interference.