Start address for the inputs of the PLC subdevice 1 (for PLC data exchange in AutomationML format). Can be used in the addressing format. PLC devices exist that consist of several integrated modules, meaning subdevices, and that have several start addresses. Such a device can consist, for example, of an internal CPU module, an internal input-output module as well as internal counter module - however with only one part number. In order to map such logical function units within a PLC device, up to twelve PLC subdevices are available to you.

Reference

Placement3DPropertyList Class
Placement3DPropertyList Members