DNP3DefaultNoScan

Controls whether addresses without a suffix are treated as event-based polling or standard polling.

New applications from 12.1.39 onwards have this property set to 1. Legacy applications will have it undefined, which is the same as 0. You can choose to update your legacy application by adding this property.

For existing applications, addresses without a suffix will always use standard polling. To use event-based polling, :NS is required.

Addresses without a suffix

Polling will be event-based, unless the object itself does not support events, such as Time and Date, File Transfer.
New data is returned by Class polling or unsolicited messages whenever the value in the device changes beyond the constraints of deadband and debounce settings..

Addresses with :DR

Will use the standard VTScada interval-based polling, returning the current value of the point.

Addresses with :NS

Treated the same as addresses with no suffix.