Siemens SIMATIC S7-1500 System Manual page 107

Hardware identifier
STEP 7 automatically assigns a hardware identifier (HW identifier) for identification and
addressing of modules and submodules. The HW identifier is used, for example, for
diagnostics alarms or for instructions, to identify the faulty module or the addressed module.
Figure 6-6
The "System constants" tab contains all hardware identifiers and their symbolic names (of
HW identifier) for the selected module.
The HW identifiers and names of all modules of a device are also available in the default tag
table on the "System constants" tab.
Figure 6-7
Automation system
System Manual, 09/2016, A5E03461182-AD
Example of a Hardware identifier from STEP 7
Example of a default tag table from STEP 7
Configuring
6.1 Configuring the CPU
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