Multiple value changes may occur between successive Publish responses from the server. These changes are stored in a monitored item queue on the OPC UA server until they can be transmitted to VTScada.
To minimize data loss, VTScada requests a queue size equal to the number of monitoring intervals contained within the subscription timeout period.
The monitoring interval is the rate at which the server checks for value changes and is determined by the scan rate of the I/O tags in the subscription.
This allows all scanned values available during a subscription lifetime to be retained, provided that the subscription remains active.
Section: Application
Default: OPCUACQueueSize =
*Restart Required (Settings.Startup property)
Related information:
