c) Damper position. Keeping the damper open will result in better temperature stability
because more heat loss is created. This is important when the temperature is set below
140F. When the damper is closed, the temperature will take longer time to drop if it is
overshot during initial heat up. At higher temperature, closing the damper will not affect
the performance much because the heat loss from the wall of the tower is increased,
d) Temperature uniformity of the smoker tower. Our test shown that when the all the
shelves were empty, the temperature inside the smoker tower is fairly uniform except the
back half of the lowest shelf that is close to the heater. User should avoid placing the
sensor too close to the heater because it does not represent the temperature of the rest
area. When the shelves are filled, temperature variation might depend on how the foods
were placed. The bottom shelf can become hotter if more food is placed in it to block the
hot air from going up.
e) Operating the controller when ambient temperature is below 32F (0C). The controller
reading is only accurate for temperature
≥
32 °F (0 °C). In addition, if the ambient
temperature is below 14 °F (-10 °C), the controller will not function because it can’t read
the temperature correctly. In that case, user can warm the sensor by holding it with their
hands. Once the sensor is above 14 °F (-10 °C), it will turn on the heater. Once the inside
of the smoker is heated to above 32 F, the controller will run by itself.
3) Initial settings
In case you have changed the some of the parameter but want to set the controller back
to its original condition, here is a list of the initial settings. (See WS-1200AS manual for
details on how to change these parameters)
Symbol Display
Description
Range
Initial
P
p
Proportional band (in 0.1 degree)
0-600
70
I
I
Integral constant (second)
0-900
600
d
d
Derivative constant (second)
0-300
150
AT
A
Auto-tune 0=off
1=on
0
Τ
Cycle rate (second)
1-100
2
SC
SC
Off set (degree)
-20~+20
0
Out
Output power reduction (%)
1-100
100
C-F
C-F
Temperature unit
°C or °F
°F
Table 1. List of system parameters and its initial settings.
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