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ized as very dynamic. Because of how the Autotune function is per-
formed, a very dynamic system would create very large overshoots
which could damage the process.
3. The system is very insulated and cannot cool down in a timely man-
ner. With such heating systems the autotuning function would take a
very long time to complete with questionable results.
During autotuning, test signals are sent to the process. The test signals
are 100% output and 0% output at the Autotune point. The Autotune
point can either be at setpoint or 10% of full scale below setpoint.
The controller performs as an On/Off controller. See diagram below.
Autotune
Point
Process
Variable
ON
ON
ON
OFF
OFF
100%
Output
0%
Time
Time
Autotune Period
