Siemens Simatic Field PG Manual page 61

Connecting
Via the MPI/DP interface, you can connect your programming devices to
MPI networks (S7-200, S7-300, and S7-400) or
PROFIBUS DP networks (DP components).
MPI/PROFIBUS DP Network
Up to 32 devices (PC, PG, or AS) can be connected to the MPI/DP interface to
form a network segment. The physical connection to the MPI/PROFIBUS DP
network is via a floating RS485 interface which is a component of the PG basic
module.
Several MPI/PROFIBUS DP network segments can be connected via repeaters.
The complete MPI/PROFIBUS DP network can comprise up to 127 stations. Data
transmission rates from 9.6 Kbps to 12 Mbps are possible in the PROFIBUS-DP
MPI network.
SIMATIC Field PG Manual
A5E00075760-04
Configuring And Operating The SIMATIC Field PG
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