Siemens SIMATIC ET 200AL System Manual page 113

Block diagram
Figure A-1 Higher-level safety circuit with safety relay
Note potential groups for safety-related shutdown
When a digital output is connected to a digital input, pay attention to the potential groups.
Depending on the configuration, 1M and 2M can then be connected, which leads to
elimination of the electrical isolation between 1L+ and 2L+.
The safety-related shutdown is not permitted if the electrical isolation is eliminated.
Note
Safe electrical separation
Maintain safe galvanic isolation for voltages higher than SELV/PELV.
Note
Safety-related shutdown for the IO-Link master
For an IO-Link master with IO-Link Port Class B, safety-related shutdown is available for the
additional supply (PIN 2 and PIN 5).
The other signals at the port are reaction-free.
Please note that the IO-Link device must have corresponding safety characteristics in order to
use safety-oriented tripping.
Distributed I/O system
System Manual, 08/2021, A5E31861578-AJ
WARNING
Safety-related shutdown of ET200AL standard modules
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