Some advanced drivers allow the rate at which a direct outstation is scanned to be temporarily increased. Such an increase in scan rate is known as scanning ‘promotion’.
An operator with the required permissions can manually increase the rate of scanning a direct outstation by using a Promote Scanning pick action.
Such promotion might be required during times of critical operation procedures, for example when feedback is required following a control action.
In order to promote the scanning of an outstation following a control, the Promote feature has to be enabled on the Form for that output point or pulse action (see Promoting Scanning of Outstations Associated with Controls).
In order to promote the scanning of an outstation while any of its points are displayed on a client—for example when a Mimic showing a point is on display—the Promote when Displaying Points feature has to be enabled on the Form for that outstation (see Define Whether an Outstation is Promoted While its Points are on Display).
You also need to define the promotion window for direct outstations by entering an appropriate period in the relevant field on the Channel or Outstation Form (see the driver-specific documentation).
At the end of a Promotion window, the server automatically returns a promoted outstation back to its non-promoted state, so that it is then included within the normal system scan. However, while an outstation is still promoted, an operator can manually return the outstation to its non-promoted state by using a Cancel Promoted Scanning pick action.
For direct outstations that have fallen back to using PSTN communications, see Temporarily Increasing the Frequency with which an Outstation is Called.