60
9.8.48 Control of additional cooling stage
Note:
Only available when the "Device function" parameter is set on either "Single device" or "Master device" and the control function parameter is set on either
"Cooling with additional stage" or "Heating and cooling with additional stages".
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 transmit-
ted 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).
9.8.49 Control of cooling additional stage - Cooling type
Options:
PI continuous, 0 – 100% and PI PWM, On/Off:
• Area (e.g. cooling ceiling) 5°C 240 min
• Free configuration
Fan coil
• Fan coil 4 °C 90 min
• Free configuration
Two cooling types (area or fan coil) with preset parameters are available to the user.
- If the required cooling type is not available, individual parameters can be specified in free configuration.
Note:
This parameter is only available when "Control value type" parameter is set either on "PI continuous, 0 – 100%", "PI PWM, On/Off“ or "Fan coil".
9.8.50 Control of cooling additional stage - P-component (x 0.1°C)
Options:
Setting option between 10 - 100
The P-component refers to the proportional band of a control. It fluctuates around the setpoint value and can be used to influence control speed with a PI
controller. The smaller the set value, the faster it reacts to the control. However, to avoid the risk of an overshoot, this value should not be set too low. A P-
component from 0.1 to 25.5 K can be set.
Note:
This parameter is only available when "Control value type" parameter is set either on "PI continuous, 0 – 100%", "PI PWM, On/Off“ or "Fan coil". In addition, the
"Cooling type" parameter must set on "Free configuration".
9.8.51 Control of additional cooling stage - P-component (min)
Options:
Setting option between 0 - 255
The I-component refers to the reset time of a control. The integral component has the effect of moving the room temperature slowly toward, and ultimately
reaching, the setpoint value. Depending on the type of system used, the reset time has to have different values. In general, the more inactive the overall
system, the greater the reset time.
Note:
This parameter is only available when "Control value type" parameter is set either on "PI continuous, 0 – 100%", "PI PWM, On/Off“ or "Fan coil". In addition, the
"Cooling type" parameter must set on "Free configuration".
Description of application and parameters
"RTC object" application
