Scheduled items are the objects and attributes that the event values are written to. A schedule can operate with an empty Scheduled Items list. The scheduling feature writes the defined value to the scheduled items at the time defined by an event. Schedules defined in an NAE can reference any item that can be mapped into an Engine or Metasys Server . Schedules defined in an FAC can reference items only within that FAC, even if those items are not mapped to an Engine. Adding items to a schedule involves selecting the item and then selecting the attribute of the item that you want the schedule to change. At the times defined by an event, the schedule writes the defined values to the scheduled attribute associated with each referenced item.
When there are no events active in the weekly schedule or exceptions, the schedule writes the Default Schedule Command to the referenced attributes. If the Default Schedule Command is set to Release, the schedule’s control over the scheduled items ends.
The table of scheduled items provides the Status Log entry for each scheduled item. The status log indicates any errors that occurred when the scheduling feature attempted to write values to the scheduled items.
A single schedule can only apply values of one data type to all items in its list of scheduled items; therefore, the first item in the Scheduled Items list becomes the key item. The key item determines the data type of the values that the schedule writes to the attributes of all scheduled items.
See the following example scenario for a description of how scheduled items work.
Example Scenario
If you use CCT and create a MASD air handling system in a field controller, you can select the OCC-SCHEDULE multi-state value as the scheduled item. The state selection modes for this item include Occupied, Unoccupied, and Standby. The application automatically manages the setpoint and logic changes when the unit switches between Occupied and Unoccupied.