Siemens S7-400 - Methods of Expansion and Networking; 5 Networking; Starting up

Installing the S7-400
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S7-400 and M7-400 Programmable Controllers Hardware and Installation
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2.16 Methods of Expansion and Networking
Introduction
Apart from the structures mentioned in this chapter, other expansions are possible,
for example, by connecting distributed I/Os or by networking. The modules with
which you can connect an M7-400 to PROFIBUS DP can be found in Section 6.9
“Starting Up a PROFIBUS-DP Subnet.”
Distributed I/Os
When an S7-400 is configured with a distributed I/O system, the inputs/outputs
operate in a distributed local arrangement and are directly connected via
PROFIBUS DP to a CPU.
One of the master-capable CPUs of the S7-400 is used.
You can use the following devices, for example, as slaves, i.e. as local
inputs/outputs:
• ET 200M
• ET 200 U/B/C
• All DP standard slaves
Networking
Two or more S7-400s can be arranged in a network for communication via the
multipoint interface.
For networking the individual S7-400s, you must interconnect their CPUs with
PROFIBUS-DP bus cables. The S7-400 is connected to the communication
network via the multipoint interface (MPI) of the CPU via:
• Bus connectors
• A PROFIBUS-DP RS 485 bus terminal
See Chapter 7 for further details.
Other networking methods require special modules.