The process automation industry uses several standards-based automation protocols, including HART, FOUNDATION Fieldbus and PROFIBUS PA to represent information made available by field instrumentation. Since each automation protocol represents field device information differently, integration of information from process automation OT (operational technology) to higher level IT systems is difficult. And with an extremely large installed base of instrumentation, it is hard to imagine how the OT/IT chasm can be bridged without a common “information model” to represent information generated by the different protocols. 

To ensure interoperability and seamless access to device information, it is necessary to standardize on the form and basic contents of the information models for certain device classes independent of a specific communication protocol, thus enabling seamless instrumentation information flow throughout the enterprise.

In short, PA-DIM is a common language for describing device data regardless of protocol, type of device or manufacturer.