Mitsubishi FX3U-4AD User Manual page 447

FX /FX /FX PLC User's Manual - Analog Control Edition
3G 3U 3UC
PID Instruction (FNC 88)
3.2.6 Differential gain (K
The filter is applied to the output at the differential operation.
Only the differential operation is affected by the differential gain (K
• When the differential gain (K
measured value (PV) caused by disturbance, etc.
• When the differential gain (K
measured value (PV) caused by disturbance, etc.
Important points
Set the differential gain (K
If the output response is too close to the disturbance, increase the differential gain (K
3.2.7 Differential time (T
Use the differential time (T
disturbance, etc. and to minimize the fluctuations.
• When the differential time (T
by disturbance, etc.
• It is not always necessary to use the differential time (when disturbance is small, for example).
Disturbance
): (S3)+5
D
) is small, the output is immediately given with regard to changes in the
D
) is large, the output is given after a long time with respect to changes in the
D
) to "0", and then adjust the operation using the input filter (α).
D
): (S3)+6
D
) to respond sensitively to fluctuations in the measured value (PV) caused by
D
) is large, it becomes to prevent large fluctuation in the control target caused
D
T
(PID operation)
D3
T (PID operation)
D1 Deviation (EV)
T
(PID operation)
D2
T (PID operation)
D3
T > T
D3
T
(PID operation)
D2
T
(PID operation)
D1
PID control: Differential operation
).
D
Setting range: 0 to 32767 [× 10 ms]
PID control: Differential operation
Time
> T
D2 D1
Time
3 Parameter
3.2 Details of Parameters
Setting range: 0 to 100[%]
).
D
L-15
K
L