Why Thermal Control Is Often Slow First and Then Overshoots
Thermal control often has a contradictory feel: temperature rises slowly at first, then overshoots near the target.
The heater is at full power, but temperature takes a long time to rise. Increasing gains makes warm-up faster, but overshoot appears near the target. Integral action removes offset, but overshoot becomes larger. Filtering makes the display smoother, but control reacts late.
This is often blamed on bad PID tuning.
The core issue is not the three gains alone. Heat transfer is slow, heat storage is significant, and feedback is often delayed.
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