Siemens SIMATIC ET 200AL System Manual page 175

Connecting
5.3 Electrical configuration of the IO-Link I/O modules
5.3 Electrical configuration of the IO-Link I/O modules
Electrical isolation
In the electrical configuration of the IO-Link I/O modules, there is electrical isolation between:
• IO-Link 1L+: Non-switched supply voltage (electronics/sensor/load supply):
Electrically isolated from 2L+ (load voltage supply)
• 2L+ port class B or M12-L power connector: Switched supply voltage (load voltage supply):
Electrically isolated from all other circuit components
Can be switched off without affecting the IO-Link 1L+
Connection of a digital output with a digital input
NOTICE
Pay attention to the potential group
When a digital output is connected to a digital input, pay attention to the potential groups.
Depending on the configuration, 1M and 2M may then be connected, resulting in
elimination of the electrical isolation between 1L+ and 2L+. The possible compensating
currents can destroy the digital module.
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 be connected through this, which leads to
cancellation of the electrical isolation between 1L+ and 2L+.
The safety-related shutdown is not permitted if the electrical isolation is canceled.
Cable protection
According to DIN VDE 0100, cable protection is required. Therefore, you must always protect
the supply lines externally.
Protect the 24 V DC supply lines against short-circuits and overloads.
Select a protective device that meets the following criteria:
• Suitable for 24 V DC supply voltage
• Suitable for cable cross-section and type of installation
• Suitable for other conditions, such as temperature
32
WARNING
IO-Link I/O modules
System Manual, 08/2021, A5E48755395-AB