Interfaces - Siemens SIMATIC ET 200S Manual

Functions of the IM 151-7 CPU
8.5

Interfaces

The IM 151-7 CPU has a coexistent MPI/DP interface X1.
The DP master module has a PROFIBUS-DP master interface X2.
The interfaces are described below.
MPI interface
The MPI (Multi Point Interface) is the interface of the IM 151-7 CPU to a PD/OP
and the interface allowing communication in an MPI network. The IM 151-7 CPU
has an MPI interface which functions with RS 485.
The typical (default) transmission rate is 187.5 kbaud. The IM 151-7 CPU supports
all MPI transmission rates.
The IM 151-7 CPU automatically sends its set bus parameters (e.g. the
transmission rate) to the MPI interface. A programming device, for example, is
thus supplied with the correct parameters and can automatically connect to an MPI
subnetwork.
Note
You can only connect PDs to the MPI subnetwork during operation.
Other nodes (e.g. OP, TP, ...) should not be connected to the MPI subnetwork
during operation, otherwise the transmitted data could be corrupted by
interference noises or global data packets could be lost.
PROFIBUS-DP interface
The PROFIBUS-DP interface is mainly used to connect distributed I/Os. You use
the PROFIBUS-DP to configure extended subnetworks. Transmission rates of up
to 12 Mbaud are possible on the PROFIBUS.
The IM 151-7 CPU has a PROFIBUS-DP interface. This can be configured to be
active or passive.
The IM 151-7 CPU as active station sends the set bus parameters (e.g. the
transmission rate) to the PROFIBUS-DP interface. A programming device, for
example, is thus supplied with the correct parameters and can automatically
connect to a PROFIBUS subnetwork. The sending of bus parameters can be
deactivated in the configuration settings.
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ET 200S IM 151-7 CPU Interface Module
A5E00058783-04