User Manual

Control concept
Desigo room automation
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An HVAC control application in the room is connected to the following:
● HVAC plant in the room via sensors and actuators
● Room coordination application
● Centralized coordination application for HVAC supply chain(s)
● Building operator via BAC workstations
● Building automation and control functions for scheduling
● Room user
The HVAC control application in the room consists of two parts:
● Application function for user requirements
● Application function for HVAC plant control
The HVAC plant control contains a control module (CFC) that implements the
control functions associated with the HVAC device.
The physical room conditions are controlled by a combination of control
methods (setpoints by operating mode).
Algorithms for room temperature sequence control operate the heating and
cooling equipment within applicable limits. The algorithm for one single heating
element is as follows (e.g., radiator):
Below is an illustration of the temperature control sequence for a more complex
HVAC plant in the room. The charts show the segregation of heating and
cooling control sequences and associated setpoints and sequencing of heat
convection by fan air flow or associated switching stages.
HVAC Plant Control
T
Supply Chain
Functions
User Request
Room Coordination
WndCont PscDet
HVAC control structure
Control concepts
Sequence control