Siemens SINUMERIK 840D sl Operating Manual page 513

Composite modules
For composite modules, such as Double Motor Modules and 120 combi modules, their internal
structure must be mapped in the XML structure. To ensure the correct display as composite
module in Topo, all the internal components belonging to such a module must be identified
with the attribute group="<name of the composite component>". In addition, the "index"
attribute with the position inside the module must be specified (MM1 → index=1, etc.) for
components of the same device class (here Motor Module).
SINUMERIK Integrate Create MyConfig - Diff, Expert, Topo
Operating Manual, 12/2017, A5E36537479B-AE
Create MyConfig - Topo
6.9 Interface Topo XML
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