PI Data Quality

Using the DataQualitySchema metadata property and PI Data Archive's SYSTEM digital state set, you can utilize the PI Data Quality mapping definition to OMF PI points.

The following dynamic type message illustrates how to specify the PI Quality Mapping:

[

{

"id": "TimeIndexed.Single.PIQuality",

"name": "Single",

"description": "Represents a PI Data Archive float32 point type.",

"type": "object",

"classification": "dynamic",

"metadata": {

"DataQualitySchema": "PI"

},

"properties": {

"Timestamp": {

"type": "string",

"format": "date-time",

"isindex": true

},

"Value": {

"type": "Number",

"format": "float32"

},

"Quality": {

"type": [

"integer",

"null"

],

"format": "int16",

"isquality": true

}

}

}

]

In the example above, we utilize the PI quality mapping. To associate the dynamic type with this quality mapping and to enable PI SYSTEM digital states to be written to the PI Points, set the DataQualitySchema metadata to a value of PI and the isquality keyword on the Quality field to true.

When the Quality field has a value of 0, PI Web API writes the Value field to the PI Point with Good quality.

When the Quality field has a value of -1, PI Web API writes the Value field to the PI Point with Questionable quality.

When the Quality field has a value greater than 0, PI Web API writes the corresponding System Digital State to the PI Point, which indicates the data is of Bad quality.

For additional information, see the SYSTEM digital state set section of the Data Archive Administration guide.