Slow rolling oscillation = too much integral. Fast jitter = too much derivative amplifying noise.
Each PID term fails with its own signature. Learning to read them turns tuning from guesswork into diagnosis.
The signature only reads cleanly on a loop that is otherwise well behaved. A slow roll can equally be a valve sticking, a sensor lagging, or two loops fighting over the same actuator — none of which is fixed by touching the integral term, and all of which look identical on the trend.
Estimate with the rule, then check it against the calculator that models it properly.
Open PID Control →