About Array Tags

Proficy historian for edge from version 2.3.1 supports array tags. The functionality of array tags is same as On-prem Historian.

You can store a set of values with a single timestamp and single quality and then read the elements individually or as an array.The following conditions apply when using an array tag:

  • You need not specify the size of an array tag. Data Archiver will store the number of elements that were written.
  • You can change a tag to an array tag later as well. However, when you do so, only the latest data is retrieved. If you want to get the old data, you must change the tag back to its previous type.
  • The maximum number of elements that an array tag can store is 10,000.
  • You cannot associate an enumerated set or a user-defined data type (UDT) with an array tag.
  • Fixed String and Scaled data types are not supported.
  • Scaling, collector compression, and archive compression do not apply to an array tag.
  • You cannot use an array element as a calculation trigger.
  • You cannot plot a trend chart for an array tag.
  • TagStats calculation mode is not supported.
Note: Note that currently Proficy Historian for Edge does not support array tags for variable string data type.