6. At any time during autotuning, you can press the “Down” button to
immediately exit back to normal operation without setting new control
gains.
7. After successfully completing the autotune routine, the system will no
longer display the “A” before each temperature on the segment LED
displays, and it will go back to normal operation. The new gains will
be stored, and the system will set itself to “AUTO” PID mode.
8. At the end of the autotune routine, the controller will print out a fuzzy
logic “System Category” classification over the serial port if VERB is
set to “On” in the settings menu. This is for diagnostic purposes and
summarizes the measured response of the test setup:
System Category
Response
1
Fast with low overshoot
2
Very fast response
3
Slower without much overshoot
4
Fast with significant overshoot
5
Moderately Slow with significant overshoot
6
Slow or with substantial time delay
7
Very Slow
9. If the controller detects that something went wrong during the
autotuning process, then it may output one of the following errors on
the segment LED displays or serial port:
9.1 Auto Err
This will be displayed on the segment LEDs any time the system aborts
without setting new control gains.
9.2 Bad gain
This will be displayed on the segment LEDs if the system completes
the autotune routine, but the control gains were range-limited because
unreasonable values were calculated. The controller will set the new
gains in this case, but they probably won’t be ideal, so you’ll want to
re-tune or use one of the static modes (FAST, SLOW, NORM).
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