ABB i-bus FCC/S 1 1 Series Product Manual page 194

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ABB i-bus KNX
Parameters
7.5.1.8.1 Basic-stage cooling control value type
Options:
This parameter is used to specify the control and control value type for the basic-stage cooling.
The standard value for the parameter is dependent on the selection in the Basic-stage cooling and
Actuate basic-stage cooling via parameters (Application parameters parameter window).
On the selection of one of the physical device outputs for the actuation of the basic-stage cooling,
the controller has a fixed pre-configuration that cannot be changed. The pre-configured controller
type is dependent here on the option selected in the Basic-stage cooling parameter.
The only exception is on the selection of Free configuration. In this situation, everything can be se-
lected and set freely.
The following table shows the dependencies:
Option selected:
Basic-stage cooling
Area cooling (e.g. cooling ceiling)
Free configuration
Fan coil unit: Water heating coil
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 (temperature setpoint minus hystere-
sis) and off as soon as a specific value (temperature setpoint 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 previ-
ously 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 pur-
pose 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.
• PI continuous (0...100 %) for Fan Coil: The fan coil controller operates like the PI continuous
controller. In addition, the fan output is also actuated in the automatic mode corresponding to
the control value for the basic-stage cooling.
The dependent Status Control value Basic-stage cooling group object is enabled as a 1-byte
group object.
For a detailed description of the individual controller types, see Explanation of controller function,
Page 365.
2-point 1 bit (On/Off)
2-point 1 byte (0/100 %)
PI continuous (0...100 %)
PI PWM (On/Off)
PI continuous (0...100 %) for Fan Coil
Note
Pre-configured controller type:
Type of cooling control value
PI continuous (0...100 %)
PI continuous (0...100 %)
PI continuous (0...100 %) for Fan
Coil
FCC/S 1.X.X.1 | 2CDC 508 200 D0211 Rev A 194
Controller type can be changed
No
Yes
No