Standard BACnet objects

The standard BACnet objects Schedule and Calendar are used for time scheduling functions in the Desigo system. These objects can be used to configure and operate time scheduling functions at different operating levels within the system and via BACnet-compatible operator units from other manufacturers.

The local PXM10 operator unit can also be used to operate the standard BACnet objects for the connected automation stations and PXC.

Function blocks

The time scheduling functions are implemented as function blocks in CFC charts of automation stations. Each automation station and each switching operation requires one schedule block. The pins of the function blocks are mapped to standard BACnet properties.

There are four versions of the schedule block, with an analog, binary or multistate output or with a variable data type (Boolean, Unsigned, Real or Enumerated). A schedule block can only contain schedule values of the same data type.

[WeekSchd] [EcptSchd]

The scheduler program consists of a weekly schedule [WeekSchd] and an exception schedule [EcptSchd]. The weekly schedule contains a 24-hour profile for each day. The exception schedule contains up to 20 profiles, which can be activated for a date or date range. The date or date range can be defined both in the schedule itself and in the calendar object.


A priority must be assigned to each of the profiles in the schedule. Based on the priority level assigned, the scheduler program determines from the priority [Prio] which profile is to be processed. The weekly schedule has the lowest priority.


The effective period [EfPrd] property defines the time period for which the schedule is active.

[PrVal] [NxVal] [NxTi]

The present value [PrVal], next value [NxVal] and next time [NxTi] are available at the output of the time schedule. [NxVal] and [NxTi] are used for optimization purposes.

Commanded objects

The time schedule also incorporates a list of references to BACnet objects and (optionally) a property which is to be controlled by the scheduler program via BACnet.


The BACnet property Relinquish_Default is the default value [DefVal] for the present value output [PrVal].