ET 200S Distributed I/O System - Fail-Safe Modules
Installation and Operating Manual, 08/2008, A5E00103686-07
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Product Overview
1
1.1
Introduction
Overview
This chapter provides information about the following topics:
●
ET 200S distributed I/O system with fail-safe modules and its place in SIMATIC S7 fail-
safe automation systems
●
Components comprising the ET 200S distributed I/O system with fail-safe modules
●
The steps you must perform, ranging from selection of the F-modules to commissioning
of ET 200S on PROFIBUS DP/PROFINET IO
1.2
ET 200S fail-safe modules
Fail-safe automation system
Fail-safe automation systems (F-systems) are used in systems with higher-level safety
requirements. F-systems are used to control processes having a safe state immediately after
shutdown. In other words, F-systems control processes in which an immediate shutdown
does not endanger humans or the environment.
ET 200S Distributed I/O System
The ET 200S distributed I/O system is a DP slave/IO device on PROFIBUS DP/PROFINET
IO that can contain fail-safe modules in addition to ET 200S standard modules.
You can use copper cables, fiber-optic cables or WLAN (
S7 Distributed Safety as of V5.4) to
assemble the PROFIBUS DP/PROFINET IO lines.
Fail-safe modules
The major difference between fail-safe modules and standard ET 200S modules is that fail-
safe modules have a two-channel internal design. Both integrated processors monitor each
other, automatically test the I/O circuits, and set the F-module to safe state in the event of a
fault. The F-CPU communicates with the fail-safe module using the PROFIsafe safety-
related bus profile.
Fail-safe power modules are used to supply load voltage to the potential group and to safely
shut down the load voltage for standard output modules.
Fail-safe digital input modules record the signal states of safety-related sensors and send
corresponding safety message frames to the F-CPU.
Fail-safe digital output modules are suitable for shutdown procedures with short-circuit and
cross-circuit protection up to the actuator.
