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CHAPTER 4 FUNCTIONS
4
4.3 Control Method
(3) PI Control
PI control is a control method in which integral elements are added to P control, thereby an offset (remaining
deviation) is compensated. By setting the integral time (I) properly, the temperature process value (PV) matches
with the set value (SV).
(a) Setting method
Among proportional band (P), integral time (I), and derivative time (D), set any value to only proportional band
(P) and integral time (I). Set 0 to derivative time (D).
(4) PD Control
PD control is a control method in which the derivative time (D) is set in addition to PD control. The control
mechanism is the same as P control.
(a) Setting method
Among proportional band (P), integral time (I), and derivative time (D), set any value to only proportional band
(P) and derivative time (D). Set 0 to integral time (I).
(5) PID Control
PID control is a control method in which derivative elements are added to PI control, thereby the temperature
shifts to a stable status in a short period of time even when a drastic change has occurred. By setting the
derivative time (D) properly, the control subject shifts to a stable status in a short period of time.
(a) Setting method
Set any value to proportional band (P), integral time (I), and derivative time (D).