Siemens SIMATIC ET 200AL System Manual page 48

Connecting
5.4 Electrical configuration of the ET 200AL
Power supply of the configuration
Two voltage groups are available for the distributed I/O system ET 200AL: 1L+ (supply
voltage) and 2L+ (load voltage)
A second infeed may be needed to supply all the modules of a configuration with the
required voltage. Renewed voltage supply of 1L+ and 2L+ can be necessary to configure
different potential groups or because the voltage is not sufficient for all modules due to the
voltage drop. Create a power balance for the selection of the infeed point of the voltage.
Note
Turning 1L+ and 2L+ on and off
In contrast to the load voltage 2L+, the operational switching on and off of the supply voltage
1L+ results in a restart of the module.
The figure below shows a configuration with a new voltage infeed for the modules. The
different potential groups have a gray background.
Figure 5-5
Reference
You will find additional information on electrical configuration and the voltage drop in the
section Connecting cables for ET 200AL (Page 50).
46
Wiring of the power supply
Distributed I/O system
System Manual, 08/2021, A5E31861578-AJ