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Configuration
Installation, Operation, and Maintenance Manual
ES-09373-1
Configuration
August 17, 2022
8.4
Configuration Menu (Continued)
8.4.2
PID Menu
PID Control
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PID control uses proportional, integral, and derivative actions together.
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As it joins all the control actions, it makes the error correction faster and more
assertive by eliminating the offset left by the proportional and derivative actions.
See the actions in graphical form in the picture below.
PID Tuning Methods
The positioner automatically adjusts the PID parameters in the calibration process,
but you can change the values for proportional gain (Kp), integral time (Tr) and
derivative time (Td) manually. To this end, there are a few methods for adjusting the
parameters (tuning).
Borderline Sensitivity Method
This method will work on the closed loop setting. It will first reduce the effect of the
integral and derivative actions to a minimum. Only then will it start with the gain
(Kp) and increase it until the controlled variable oscillates with the amplitude that is
constant making small perturbations in the system.
The most common adjustment is the one that reaches a quarter of the previous
amplitude. This method can be used in many processes.
Reaction Curve Method
This method is widely used in first order systems since it is less complex. It will present
an S-shaped curve through the two constants delay (L) and time (T), through the
K-coordinate.
Figure 8-10 PID Control Chart