What Is The Et 200 Distributed I/O System; A Typical Profibus-Dp Installation - Siemens SIMATIC ET 200L Manual

Product Overview
1.1

What Is the ET 200 Distributed I/O System?

What Is the When a system is installed, the input/output modules are normally installed
ET 200?
centrally in the programmable logic controller.
If inputs and outputs are made at long distances from the programmable logic
controller, there may be long runs of cabling which are not immediately com-
prehensible, and electromagnetic interference may impair reliability.
In such systems, we recommend you to use the ET 200 distributed I/O sys-
tem:
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What Does the
The ET 200 distributed I/O system consists of active (master) and passive
ET 200 Consist (slave) nodes that are interconnected via the PROFIBUS-DP.
Of?
S7-300M7-300 S7-400M7-400
ET 200L
Figure 1-1

A Typical PROFIBUS-DP Installation

PROFIBUS-DP PROFIBUS-DP (DP means distributed I/O) is an open bus system conform-
ing with IEC 61784-1:2002 Ed1 CP 3/1. The PROFIBUS-DP consists of a
DP master and DP slaves.
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The controller CPU is located centrally.
The I/O (input/output) system operates locally in a distributed fashion.
The ET 200 high-performance bus system ensures that the CPU and I/O
system communicate with each other without problems owing to its high
data transfer rates.
S5-95U
ET 200S
DP master: The link between the controller and the distributed I/O sys-
tem is the DP master. The DP master exchanges data with the distributed
I/O system over the PROFIBUS-DP and monitors the field bus.
DP slave: The I/O devices are connected as DP slaves. DP slaves process
data locally from the sensors and signal control elements in such a man-
ner that they can be transferred over the PROFIBUS-DP field bus.
PU or PC
DP master
PROFIBUS-DP
DP slaves
Other field devices
ET 200L Distributed I/O Device
EWA-4NEB 780600902-05