Page 218 - Basic Course

KNX BASIC COURSE

11 Planning a project: Example

11.1 Requirements / regulations (specification text)

A bus line contains the equipment of a floor with 8 rooms. The functional requirements for
each individual room are:
3 dimmable lighting circuits; 4 x 58 W; can be manually switched both separately as
well as together, changeover switch to automatic operation
2 shutters, proportionally adjustable, can be manually controlled both separately as
well as together
1 radiator, with proportional control and the corresponding heating controller
2 window contacts, which lower the temperature when the windows are opened
1 room information and control panel, displaying the functions and values of the
temperature controller (setpoint and current temperature, night/day operation mode),
indicating storms and displaying the state of the shutters and lighting control
(manual/automatic) and also allowing to control the latter
for the operation 2-fold or 4-fold push-buttons, also realizing a central function: basic
lighting (2 of 3 strips of lights) on; all lights off + shutters up.

Moreover, a weather control unit is used, which amongst other things has the following
functions for the rooms:
Wind sensor: raising shutters in the event of a storm
Light sensor: when a pre-determined brightness limit is exceeded, closing of shutters,
switching on lighting control and proportional control of slats, raising the shutters at
nightfall
In addition, a central time switch is used, which

controls the room temperature profile centrally on a weekly basis
switches off lights at night when still turned on
An information panel is used per floor, which displays for each room

whether a window is opened
current temperature values and setpoint
whether a light has been left on somewhere
position of shutters (has limit of 30% been exceeded?)

On a summary page for each floor, the following should be displayed:
at least 1 window open – yes/no?
at least 1 light on – yes/no?
at least 1 shutter lowered (more than 30%)?
In order to generate group signals, appropriate logic modules must be used. The
automatic slat function depending on external brightness is implemented stepwise (3
steps) by means of an analogue threshold value converter.
All status signals – including the group signals – should run centrally in a building
visualisation.

Home and Building Management Systems KNX Association
KNX Project Design with ETS: Advanced ETS4_Planning complex_E0411c 42/59