Using A Single-Channel, One-Sided I/O - Siemens SIMATIC S7-400H Manual

6.2

Using a Single-Channel, One-Sided I/O

What is a single-channel, one-sided I/O?
With the single-channel, one-sided configuration single input/output modules are
present (single-channel). The input/output modules are located in just one of the
subsystems and are only addressed by that subsystem.
A single-channel, one-sided I/O configuration is possible in
central controllers and expansion units
distributed I/Os
The single-channel, one-sided I/O configuration is to be recommended for
individual input/output channels for which normal availability of the I/O is sufficient.
Figure 6-1
S7-400H Programmable Controller Fault-Tolerant Systems
A5E00068197-04
Rack 0
Single-Channel, One-Sided I/O Configuration
Using I/O on the S7-400H
Rack 1
Single-channel, one-
sided I/O modules in the
central controller
Single-channel, one-
sided distributed I/O,
say ET 200B
6-3