User Guide

Schedules
Schedules Reference
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Siemens
User Guide Version 3.0
A6V10415471
Building Technologies
2017-11-30
an entry for Occupied/Unoccupied, save it, and then drag it from System Browser
to a schedule of your choice. The schedule will determine what time the command
executes, the start and end dates, and the frequency of repetition.
BACnet calendars allow you to override a scheduled event. In this sense, you can
consider them as exception schedules, consisting of dates only. When you create
a calendar, you can choose specific dates (January 15), a date range (August 1 –
31), or a week and a day you want the exception to run (third week of the month,
on Wednesday). All calendars are associated with a schedule. If you want to
reduce energy costs in your building during company holidays, for example, you
could create a holiday calendar. On these days, your calendar might command the
system to reduce the output of heating or cooling systems when the building is
unoccupied.
More About BACnet Schedules
Schedules consist of a name and description, a toolbar for working with the
schedule, a date picker, several tabs (Schedule Entries, Outputs, Exceptions, and
Setup), and schedule details.
More about Views
Even though you can schedule entries from the weekly view, the weekly view
shows only the resulting schedule and not the details of the schedule. For more
flexibility in visualizing and creating schedule entries, you can use the detail
column of the daily view instead.
Default Date
By default, every new schedule begins with the current date and never ends. Once
a new schedule is opened, you can choose the start and end date for the schedule.
Default State
By default, the system automatically creates weekly schedule entries for the default
state, which you can modify. The Release (NULL) check box allows you to bypass
the established priority and return an object to its default value. For example, to
return control to lower priority commands, check the Release (NULL) check box for
the schedule default, and then create a schedule entry with the Default check box
checked. This will write BACnet null to the priority slot for the schedule, returning
control to the system.
Default Schedule Behavior
When you select a BACnet schedule from System Browser, the Date Picker
defaults to the current date, and the Schedule Entries tab becomes active.
About Priorities
The Present Value of some object types is based on a command priority and
established in a hierarchy that ranks from highest (1 – Manual Life Safety) to
lowest (16 - Available). The hierarchy determines which source has priority over
another to change the value of an object. To command one of these object types,
you—or an application—must have a command priority equal to or greater than the
current command priority of the object. Typically, PPCL is set to priority 16, and
schedules are set to priority 15.