Siemens SIMATIC S7-1500 Automation System System Manual page 84

Configuring
7.1 Address assignment
Hardware identifier
In addition to the I/O addresses, a hardware identifier (Hardware identifier), which is used to
identify the module, is assigned automatically by STEP 7. Such a Hardware identifier is also
assigned to submodules.
The Hardware identifier consists of an integer and is output at diagnostic messages by the
system. This identifies the faulty module or the functional unit.
Figure 7-6
You also use the Hardware identifier for a series of instructions in order to identify the
module to which the instruction should be applied.
The Hardware identifier cannot be changed.
The Hardware identifier is assigned automatically when components are inserted in the
device or network view, and entered in the "Default tag table" of the PLC tags. A name is
also assigned automatically for the Hardware identifier. These entries in the "Default tag
table" of the PLC tags cannot be changed either.
Figure 7-7
84
Example of a Hardware identifier from STEP 7
Example of a default tag table from STEP 7
S7-1500 Automation System
System Manual, 01/2013, A5E03461182-01