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OSIsoft, LLC


The AF SDK is a Microsoft .NET based programmatic library that provides structured access to the variety of data stored in the OSIsoft PI System. This data includes:

  • Assets and their properties and relationships
  • Time Series data from the PI Data Archive and other sources
  • Event frames that record and contextualize process events

The AF SDK is designed for easy access from Microsoft .NET languages like Visual Basic .NET (VB.NET), C#, and Managed C++. The AF SDK is available for .NET 4.6.2 Frameworks and targets Any CPU so that it is available for both 32-bit and 64-bit Windows operating systems. If you are using .NET 3.5, please see What's New in PI AF 2018 SP3 Patch 2.

The AF SDK allows users to build applications with data from one or more PI Systems as well as external systems. Users start by creating an asset model that organizes and structures their data according to objects that they are most familiar with, such as physical objects in their processes like reactors, transformers, and meters. The basis for the asset model is an element, which contains attributes that can reference PI System data, design data, or data from other systems. Event frames allow users to associate or mark events which occur over a time span with those assets. By creating relationships between elements, users can quickly create an asset model that personalizes the way they want to view and work with their data. Since the AF asset model can span PI Data Archives it allows customers to organize and search for PI System information across multiple PI Data Archives. PI AF also includes a real time calculation engine that allows users to configure, schedule and run calculations written using Performance Equation syntax acting on their AF attributes. Calculation results can be stored as time series data in PI Points or used to create event frames enabling users to mark important events and associated time spans in their processes. Templates are supported throughout PI AF ensuring standardization and consistent representation of assets. Client applications including but not limited to, PI Vision, PI DataLink, PI ProcessBook and PI Integrators can utilize the asset models to provide context driven displays, reports and analyses. The Namespaces section provides documentation of the objects and example code that shows how to program with the object in Visual Basic .NET and C#.

The AF SDK is not limited to only interacting with the AF Server. It provides rich, powerful methods to interact directly with the PI Data Archive and is almost always more appropriate to use than the older PI SDK. The AF SDK data access methods in the OSIsoft.AF.Data namespace and the OSIsoft.AF.PI namespace supersede the functionality provided by PI SDK. Though the PI SDK is still available, it is more appropriate to use AF SDK than the PI SDK, except in architecture that demands only native code.

AF SDK Library Reference
Version 2.10.8

The What's New page will provide an overview of recent changes in the AF SDK Library.

The following high-level hierarchy diagrams will provide an overview of each area within the library.

Enabling Operational Intelligence