9
Slow cooker, 7 quart
180
700
40
Slow cooker, 4 quart
54
60
15
Slow cooker, PD mode (low overshoot)
40
0
40
Bradley Smoker
70
600
150
Please note that the P value in table is in Fahrenheit unit. If the controller is using
Celsius unit, divide the P value by 1.8. If you switch from Fahrenheit display to
Celsius, the controller will automatically convert all the settings.
4) Controller System Configuration Parameter.
This section discusses how to configure the controller for a specific application. For most
sous vide cooking users, there is no need to read this section. The controller’s default
setting is for most common configurations of sous vide cooking.
The controller parameters are divided into two groups.
A)
The first group of parameters is related to the control performance. They need to be
adjusted based on the system to be controlled. Table 3 shows the list of these
parameters, their range and initial set value.
Table 3. List of control parameters and its initial settings under code 166.
Symbol
Display Description
Range
Initial
P
P
Proportional band (in 0.1 Degree)
0-600
180
I
I
Integral constant (second)
0-900
700
d
d
Derivative constant (second)
0-300
40
AT
AC
Auto-tune
0=off 1=on
0
T
C
Cycle rate (second)
1-100
2
Details about each parameter
P. Proportional band. It is in 0.1 degree units. This parameter controls the output
of the controller based on the difference between the measured and set
temperature. Larger the P number means the weaker the action (lower gain). e.g.
If P=100, the proportional band is 10 degree (100 x 0.1=10). When the sensor
temperature is 10 degrees below the proportional band (10 degrees below the
setting), the controller will have 100% output. When the temperature is 5 degrees
below the set point, the output is 50%. When the temperature is equal to the
setting, the controller will have 0% output (assuming integral and derivative
functions are turned off). This constant also affects both integral and derivative
action. Smaller P values will make the both integral and derivative action stronger.
Please note the value of the P is temperature unit sensitive.
If an optimized P
value was found when operating the controller in Celsius, it needs to be multiplied
