ABB i-bus KNX Product Manual page 102

®
ABB i-bus KNX
Parameters
The following table shows the dependencies:
Option selected:
Basic-stage cooling
Area cooling (e.g. cooling ceiling)
Free configuration
Table 15: Table of controller configuration dependencies
The differences between the individual controller types are explained in the following:
•
2-point 1 bit (On/Off): 2-point control is the simplest form of control. The controller switches on if
the room temperature has dropped below a specific level (setpoint temperature minus hysteresis) and
off as soon as a specific value (setpoint temperature plus hysteresis) is exceeded. The switch-on and
switch-off commands are sent as 1-bit commands. The dependent Status Control value Basic-stage
cooling group object is enabled as a 1-bit group object.
•
2-point 1 byte (0/100 %): This is also two-point control as above. The difference is that switch-on and
switch-off commands are sent as 1-byte values (0 %/100 %).
The dependent Status Control value Basic-stage cooling group object is enabled as a 1-byte group
object.
•
PI continuous (0...100 %): The PI controller adjusts its output value, between 0 % and 100 %,
to the difference between the actual value and setpoint and permits exact regulation of the room
temperature to the setpoint. It outputs the control value on the bus as a 1-byte value (0...100 %).
To reduce the bus load, the control value is only sent if it has changed by a previously specified
percentage in relation to the value sent last. In addition, the control value can be sent cyclically.
The dependent Status Control value Basic-stage cooling group object is enabled as a 1-byte group
object.
•
PI PWM (On/Off): This is also a PI controller. The output is as a 1-bit command. For this purpose
the control value calculated is implemented using a pulse-pause ratio.
The dependent Status Control value Basic-stage cooling group object is enabled as a 1-bit group
object.
For a detailed description of the individual controller types, see
234.
100 2CDC508220D0211 Rev. A | VC/S 4.x.1
Note
Pre-configured controller
type:
Type of cooling control value
PI continuous (0...100 %)
PI continuous (0...100 %)
Explanation of controller function, page
Controller type can be
changed
No
Yes