Learn how numeric values for attribute values are displayed

Prior to PI AF 2018, PI System Explorer rendered numeric data types in displays with high levels of precision. For example, the Single and Double data types have a precision of seven and fifteen digits respectively. High precision levels are not always useful in real-time situations, or for PI AF client products. For example, a temperature gauge may only display a precision of three digits, so process engineers are unlikely to require a greater degree of precision for mathematical calculations.

Beginning with PI AF 2018, the Use DisplayDigits for Attribute and Attribute Template values system option is enabled and ensures that the default setting of the DisplayDigits property is used to display attribute values: -5, or a total of five digits overall. This is the same default setting used for PI points on Data Archive.

When creating attribute templates, you can now control the number of digits you want to see for individual attributes in the Display Digits field:

• You can enter a negative number up to -20 to indicate the total number of digits to display.

• You can enter a positive number up to 10 to indicate the number of digits after the decimal point to display, including trailing zeros.

When you are editing an attribute value, the actual number is displayed rather than the truncated number established by the Display Digits field.

For attributes that are not based on a template, the precision of PI point data references is obtained from the PI point itself.

Note: On upgrades, existing attributes configured with a PI Point data reference are not updated to obtain their DisplayDigits value from the PI point: they are set to -5.