Daikin R-32 rooftop Series, Operation Manual

Page: 22 / 40

Translation from original instructions
Packaged Rooftop
22
We reserve the right to make changes without any prior notice.
UATYA
4P645203-1
The values set in parameters “ST9” for cooling and “STH9” for heating determine the control probe type, as follows:
- 0 = temperature probe on air delivery line;
- 1 = temperature probe on air return line;
The values set in parameters “ST11” for cooling and “STH11” for heating determine the type of temperature control,
as follows:
- 0 = proportional.
- 1 = "Cascade";
- 2 = PID.
5.3.1 Thermoregulation in cooling mode
The thermoregulation of the unit depends on parameter “ST9”, which identifies the reference probe for the temperature
setpoint (parameter “ST1”), and on parameter “ST11” which determines the type of temperature/humidity control.
In proportional control mode, the controller activates the available resources as the value read by the reference probe
increases in comparison to the setpoint value.
When “Cascade” temperature/humidity control is selected, the controller uses it to enable the resources and at the
same time monitor the air temperature in the delivery line.
In PID control mode, the controller activates the available resources as the demand increases. The controller
calculates the demand and checks the value measured by the probe against the setpoint value and according to its
variation over time using the parameters set in the PID.
Proportional temperature control
If parameter “ST11” is set to “0”, proportional control is enabled.
The parameters involved in proportional temperature control are shown in the table.
The values of the parameters are representative. In specific cases, different values can be set.
Parameter Value UM Description
ST1 24.0 °C Temperature setpoint
ST4 2.0 °C Proportional control - Cooling - Activation differential
ST5 0.1 °C Proportional control - Cooling - Neutral activation area
ST6 0.1 °C Proportional control - Cooling - Offset
A graphical representation is shown below.
ST5 ST6 ST4
100
0
%
ST1
SdR °C
Fig. 4 Graphical representation of cooling demand
In addition to the parameters listed in the table, the abbreviations in the graph are:
- SdR = reference probe;
- % = percentage demand value.