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8.2 Selecting PID Control or ON/OFF Control
Selects PID or ON/OFF control action.
Select PID or ON/OFF control action in [OUT1 proportional band] in Sub setting mode.
If ‘OUT1 proportional band’ is set to 0 (zero), the unit performs ON/OFF control action.
Factory default value is PID control.
PID control
Proportional (P) action suppresses overshoot and hunting, Integral (I) action corrects offset,
and Derivative (D) action converges rapid temperature change due to disturbance in shorter time.
Optimum values of P, I, D, ARW for PID control can be automatically set by performing AT.
ON/OFF control
When PV is lower than the SV, the control output is turned ON, and if PV exceeds the SV,
the control output is turned OFF.
Overshoot, undershoot and hunting are generated in ON/OFF control action.
(Example) Selecting PID control
Power ON
RUN mode
PV/SV Display
+
Sub setting mode
AT/Auto-reset Perform/Cancel [37]
OUT1 proportional band. [38]
or
Set a value except 0 (zero).
(Many times) or
(3 sec)
RUN mode
PV/SV Display
Now, selection is complete.
Reference
• P control action: When [Integral time] and [Derivative time] are set to 0 (zero).
• PD control action: When [Integral time] is set to 0 (zero).
• PI control action: When [Derivative time] is set to 0 (zero).
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