Basic elements of INTERBUS

To fulfill the individual requirements of a system, different bus components are necessary, e.g. local bus stations and bus terminal modules. The terminology for the basic elements occurs in every topology and should be known to the user.

Connection

The controller board is the master and monitors data traffic. It transfers output data to the corresponding modules, receives input data and controls the data transfer. In addition, diagnostics messages are displayed and error messages are sent to the host system.

Remote bus

The controller board is connected to the remote bus stations via the remote bus. A branch of it is referred to as a remote bus branch. Physically, data can be transmitted via copper cables (RS-485 standard), optic fibers, optical data links or other media. Special bus terminal modules, specific I/O modules or devices, such as robots, drives or operating equipment can act as remote bus stations. They feature local voltage supply as well as electrical isolation to the outgoing segment. The installation remote bus has both wires for data transmission and for the supply for the connected I/O modules and the sensors.

The individual components of an INTERBUS network

Bus terminal module

The bus terminal module is connected to the remote bus. The distributed local buses with the I/O modules form the connection between INTERBUS and the sensors or actuators and branch off from the bus terminal module. The bus terminal module divides the system into individual segments and therefore allows individual branches to be disabled during operation. The modular electronics of the connected I/O modules can be supplied with voltage from here. The bus terminal module refreshes the data signal (repeater function) and ensures electrical isolation between the bus segments themselves. Local bus The local bus branches off from the remote bus via a bus coupler and connects the local bus stations with each other. Branches are not permitted at this level. The logic voltage is provided by the bus terminal module and the switching voltage for the outputs is applied separately at the output modules. Local bus stations are typically I/O modules for setting up a distributed substation.

Loop

Sensors and actuators that are distributed on machines or systems are networked with the INTERBUS Loop. The two-wire, unshielded cable also takes over the tasks of data transfer and power supply to the connected stations. In addition, there are different INTERBUS modules designed for specific requirements, such as particularly flat modules or motor starters.