10
PID CONTROL FUNCTION
10.1
Outline of Function
PID control is performed by PID control instruction. The PID instruction requires the system to calculate the output (MV) value
from the measured (PV) value. Through combining the P (proportional) action, I (integral) action, and D (derivative) action the
target (SV) value can be obtained.
• Alarm output function
The alarm function can be set for input variation (measured value) or output variation (value).
• Setting limit values
The upper limit and lower limit can be set for the output value.
• Auto-tuning function
The proportional gain (KP), integral time (TI) and differential time (TD) can be set automatically for both the limit cycle method
and step response method.
• Operation method of the PID instruction
Both PID speed type operation and measured value differential type operation are executed.
CPU module
Target value (SV)
PID instruction
10 PID CONTROL FUNCTION
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10.1 Outline of Function
Measured value (PV)
Controlled object
Output value (MV)