Page 47 - Advanced Course
P. 47

KNX ADVANCED COURSE

            The areas of application of the control systems are as follows:

            Table 7

                                              Individual room control         Heating systems without direct boiler       Heating systems with boiler control
                                                                              connection

            Applications                      No intervention necessary in the   For installations with mixing valves in the   For installations with direct access to
                                              heating system, only changing   heating circuits without direct access to the   the boiler via KNX
                                              valve elements                  boiler via a KNX gateway

            Principle                         Opening/closing of load circuits   Mixing and control of load circuits, increase and  Boiler control and mixing of load circuits
                                              (rate regulation)               reduction of flow temperature via analogue
                                                                              and/or digital input signals
            Cost reduction by decrease in     Dependent on the room usage     Considerable savings for installations with   Large reduction as the complex
            energy consumption                (little use – more savings)     storage capacity as only the required energy is   installation is controlled at the optimum
                                                                              taken from the tank and thus long operating   level
                                              No influence from the boiler
                                                                              times
                                                                                                                          No heat requirement = boiler OFF
            Cost of purchase                  Low                             Medium                                      High

            Device example                    Individual room thermostat,     Central control unit or via analogue/digital   Manufacturer-specific gateways for the
                                              heating actuator + electrothermal   inputs or outputs in a PLC e.g. with proprietary   specific installation type
                                              drive or electromotive drive    sensor or sensor with KNX capability,
                                                                              mixed circuit controller
                                                                              (e.g. shutter actuator + mixing valve),
                                                                              pump control
                                                                              (e.g. switch actuator + pump)
                                                                              0-10 V interface
                                                                              (increase or reduce boiler temperature)









            Home and Building Management Systems                                                                                              KNX Association
            HVAC Control with KNX                                            HVAC_E0813b.doc                                                        Page 22/60
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