About analog summary replication

Analog summary replication produces summary statistics for analog tags. The statistics relate only to the recorded interval. Statistics available are:

• Time-weighted average

• Standard deviation

• Integral

• First value in a period with timestamp

• Last value in a period with timestamp

• Minimum value in a period with timestamp

• Maximum value in a period with timestamp

• Start time of summary period

• End time of summary period

• OPC Quality

• Percentage of values with Good quality

• Value

When you retrieve the data, you specify which calculation you want to return. For more information, see Querying the AnalogSummaryHistory view in the AVEVA Historian Retrieval Guide.

The functionality provided by analog summary replication is similar to using the minimum, maximum, average, and integral retrieval modes. For a comparison example, see Querying aggregate data in different ways in the AVEVA Historian Retrieval Guide.

When you use the AVEVA Historian SDK to retrieve analog summary tag data, the values returned through the SDK for analog summary tags from history correspond to the "Last" values in the AnalogSummaryHistory table when using defaults. Use the corresponding retrieval mode to get the minimum, maximum, average, slope, and integral values.