Units of Measure (UOM) and PI AF

Some connectors can detect a value's unit of measure (UOM) and description. The unit's representation in PI AF depend on the unit representation in the data source and the connector behavior. The connector may attempt to map the unit from the data source into a standard unit abbreviation. The PI AF UOM feature enables automatic unit conversion in client applications.

The UOM field value of the data reference configuration string is a standard unit abbreviation as defined by the International System of Units or a UOM defined in PI AF. When the unit representation by the data source is non-standard or not a recognized PI AF UOM, the PI Data Reference configuration string UOM field is not added to the data reference.

If PI AF does not recognize a unit or the connector cannot map the unit into a standard unit, you can create a unit of measure in the PI AF UOM database. For more information, see the PI Server topic Units of measure in PI AF.