How it works

The user program of the automation system can access the inputs/outputs of the modular ET 200M I/O devices as well as the inputs/outputs of the central controller.

Communication over the bus system is fully handled by the master interface in the central controller and by the IM 153 interface.

The diagnostics functions verify the proper operation of the ET 200M.

The ET 200M can diagnose:

• Module errors
• Short-circuits (outputs)
• Bus faults, i.e. incorrect data transmission
• 24 V DC load voltage supply
• Hot-swapping of I/O modules

The diagnostics data is evaluated as follows:

• Decentralized, with diagnostics LEDs on the ET 200M
• Centrally, in the central module (CPU) of the programmable controller.

Configuration and parameterization PROFIBUS

Calculation of the required message frame length for the configuration and parameterization message frames

The DP master must provide the required amount of configuration and parameterization data. A few masters offer a shorter configuration and parameterization message frame length. For example, the maximum lengths of the configuration and parameterization message frames in the S5-95U/DP are 32 bytes each. This means in this example that a maximum of 3 modules can be plugged into the ET 200M, where one of them may be parameterizable.

When connecting the device to master modules which have not been configured with COM PROFIBUS or STEP 7 (operated on master modules of other manufacturers), a fixed pre-allocated GSD file may be created by COM PROFIBUS as of version 3. This is then loaded into the configuration tool of the other vendor and can be used for simple configuration of the station.

This allows use of the convenient plain text parameterization of COM PROFIBUS, eliminating the hexadecimal code entries in the configuration tool of the vendor.

A suitable master is required to use the full addressing range of the IM 153.