Description of application and parameters
Application "RTC object"
KNX Technical Reference Manual 1473-1-8914 / 2CKA001473B8914
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Options:
2-point 1 bit, Off/On
2-point 1 byte, (0/100%)
PI continuous, 0-100%
PI PWM, On/Off
Fan coil
The actuation of the control valve is determined by the selection of the controller type.
–
2-Point 1 Bit, Off/On
: The 2-point control is the simplest type of control. The controller
switches on when the room temperature drops below a certain level (setpoint temperature
value minus hysteresis) and switches off when a particular value (setpoint temperature
value plus hysteresis) is exceeded. The switch-on and switch-off commands are transmitted
as 1-bit commands.
–
2-Point 1 Byte, 0/100%
: This is another two-point control as described above. In this case,
however, the switch-on and switch-off commands are transmitted as 1-byte values (0% /
100%).
–
PI continuous, 0-100%
: The PI controller adjusts its output value between 0% and 100% to
match the difference between the actual value and the setpoint value and enables a precise
regulation of the room temperature to the setpoint value. It sends the control value to the
bus as a 1-byte value (0% - 100%). To reduce the bus load, the control value is only
transmitted if it has changed by a predefined percentage in relation to the previous sent
value. The control value can also be transmitted cyclically.
–
PI PWM, On/Off
: This also is a PI controller. Here, the output is a 1-bit command. For this to
occur, the calculated control value is converted into a pulse-interval signal.
–
Fan coil
: The fan coil controller operates like the PI continuous controller. In addition, it
allows the separate activation of the fan in the fan coil unit (e.g. fan speed levels 1 - 3).
