Siemens SIMATIC ET 200AL System Manual page 64

Configuring
Configuration - PROFIBUS maximum configuration
Each of the connections for ET-Connection occupies a slot in the configuration. The slot for
ET-Connection1 is statically defined in the PROFIBUS GSD file. ET-Connection1 is always
permanently installed in slot 1. Always place the topology module for ET-Connection2 on slot
18. You do not need to fill slots in the configuration for ET-Connection1 with dummy
modules.
The fixed slot assignment of ET-Connection1 and ET-Connetion2 offers you the following
advantages:
• You can expand ET-Connection1 and ET-Connection2 without a high workload; for
ET-Connection1 you need to remove the placeholder, the I/O module is placeable (no
placeholders are needed for ET-Connection2)
• You cannot configure more modules on ET-Connection1 or ET-Connection2 than are
allowed.
• Transparency in configuration control
• Simplification of diagnostics alarms and troubleshooting
The figure below shows the maximum configuration with modules of the ET 200AL
distributed I/O system.
Figure 6-2
62
PROFIBUS maximum configuration
Distributed I/O system
System Manual, 08/2021, A5E31861578-AJ