Defines the type of scanning performed by the software. Constant Scanning means the Tag is always scanned as long as the SCADA node is running. Constant scanning must be used for all I/O points that require continuous update (alarming, trends, logs, batch, scripts, logic).
Display Scanning occurs only when a Display is being viewed with this tag on it. Display Scan is for infrequently accessed tags, like tuning parameters and setpoints. Display Scan is a means of optimizing or increasing communications throughput.
Some drivers provide other Scan options. Scan Type is chosen from a pull down menu showing valid scan types for this device.
Range:
Constant Scan, Display Scan
Field Type:
Text
Tag
fields:
.SCANTP
read only
Parameter Scan Type defines the initial Scan Type for Tags and BLOCK:PARAMETERS created using this parameter. Parameter Scan Type can save time and typing or enforce a standard if this parameter will be used in a predictable way to create Tags or Blocks.