Reading OPC quality into a digital PI point

To store OPC quality in a digital PI point, use transformations and scaling to translate quality to a digital state set of Bad Value, Questionable Value, Invalid Value, or Good Value.

To define such a PI point, set location2 to 4 to read the quality of the item rather than its value, then define a mathematical transformation that translates the quality values to an integer from 0 to 3. Divide the quality number by a conversion factor that produces the proper number.

OPC quality is returned in ranges of values, as follows:

Because each range has the same size (decimal 64), you can use a simple conversion to obtain the corresponding digital state, as follows:

Define the point attributes as follows: