This mode evaluates the configured trigger condition at the configured scan rate. When the condition is true, communication switches to the secondary device. When the condition is not true, communication switches to the primary device.

A common use of this mode is driving switchover between redundant remote servers communicating with the server through two client driver devices. In this case, a Quality Not Good trigger is configured using a tag on the primary remote server as the trigger item. When the quality of that item transitions from good to bad (indicating some sort of communications problem between the remote server and its data source), the server triggers a seamless switch to the secondary remote server.