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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. Users 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 where the food
is placed. The bottom shelf can become hotter if more food is placed in it to block the hot
air from going up.
9. Tuning the controller
This controller is shipped with the system parameters set for the Bradley Smoker. The
user should not change these parameters if you want to control a Bradley Smoker.
Otherwise, if you feel that performance is not ideal, you can try to manually tune the
system or run the auto-tune again. For detailed information on how to tune the controller,
please read the section 10 for tuning the controller.
10. Auto-Tune
This section can be ignored if you are using the controller to control the Bradley Smoker
because the controller already set for it.
The controller's most powerful feature is its ability to regulate virtually any cooker with
stable temperature manipulation. For stable temperature control, the controller requires
two things; (1) the controller must be set to the correct power level (see next section) and,
(2) that it must be
tuned
to the cooker being used. Tuning is the process that matches
the control characteristics of the controller to the heating characteristics of the cooker.
The controller is said to be tuned to the cooker when its memory is programmed with
values telling it how fast the cooker warms up, cools off, and how efficiently it transfers
heat. For example, consider the difference between a heat lamp and a hot plate. When
electricity is applied to a heat lamp it begins to heat instantaneously. Additionally, when
it's turned off, it stops heating instantaneously. In contrast, a hot plate may take several
minutes to begin heating when electricity is applied and even longer to start cooling
when electricity is turned off. But to do this, it must be programmed with the time
constants. Describing how fast the heater heats when electricity is turned on and how
fast it begins to cool when it's turned off. These time constants are called the
tuning
parameters.
Every type of cooker has its own unique set of tuning parameters. For the controller to
heat with stability, it must have programmed with the tuning parameters for the cooker
currently being used.
