Siemens SIMATIC ET 200AL System Manual page 20

System overview
2.2 What are fail-safe automation systems and fail-safe modules?
Use in SIMATIC Safety F-systems
The fail-safe ET 200AL modules can be used with STEP 7 Safety Advanced from V17 with
PROFINET and direct ET connection configurations together with an F-CPU.
The fail-safe modules can only be used in safety mode. Fault safe and non-fault safe modules
can be combined within one ET 200AL ET connection.
Achievable safety classes
The fail-safe modules are equipped with integrated safety functions for safety mode.
You can achieve the safety classes of the table below:
• With the appropriate parameter assignment of the safety functions in STEP 7
• With a specific combination of fail-safe and non-fail-safe I/O modules
• With a special arrangement and wiring of the sensors and actuators
Table 2- 1
The safety performance of your installation depends on the design and ongoing
maintenance of the individual complete safety function.
SIMATIC fail-safe CPUs and ET 200AL fail-safe modules have logic processing components
with certified safety integrity levels, provided they are operated in accordance with
classifications, specifications, and instructions.
Failure to adhere to this may cause damage or unpredictable operation, resulting in fatal or
serious injury and/or property damage.
To achieve the level of safety you require, you need to select all components of your plant
and construct and maintain them in accordance with accepted safety standards and
practices.
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Safety classes that can be achieved with ET 200AL in safety mode
According to IEC 61508
SIL2
SIL3
SIL3
WARNING
Safety class in safety mode
According to ISO 13849-1
Category 3
Category 3
Category 4
(PL) Performance Level d
(PL) Performance Level e
(PL) Performance Level e
Distributed I/O system
System Manual, 08/2021, A5E31861578-AJ