Mitsubishi Electric FR-F800 Series Instruction Manual page 438

5.11.7 PID gain tuning
Changing the PID control manipulated amount and measuring the PID control response enable automatic setting of the
constant optimal for PID control.
For tuning, use the step response method or the limit cycle method.
Pr.
1211
PID gain tuning timeout time
A690
1212
Step manipulated amount
A691
1213
Step response sampling cycle
A692
1214 Timeout time after the maximum
A693 slope
1215
Limit cycle output upper limit
A694
1216
Limit cycle output lower limit
A695
1217
Limit cycle hysteresis
A696
1218
PID gain tuning setting
A697
1219
PID gain tuning start/status
A698
 Step response method
• In the step response method, the manipulated amount is changed step by step for the real system. From the change in the
measured values, the maximum slope (R) and the equivalent waste time (L) are calculated to determine each constant.
Measured value[%]
PID gain tuning start
• The step manipulated amount (Pr.1212 - 1000) is added to the present manipulated amount.
Downloaded from ManualsNet.com
Name
100 s
1000%
1 s
10 s
1100%
1000%
1%
0
0
Manipulated
amount[%]
Maximum Maximum Maximum
slope R slope R slope R
(R=Y/T) (R=Y/T) (R=Y/T)
Equivalent
waste time L (s)
STF
PID
PGT
search engine
Initial
Setting range
value
1 to 9999 s
900% to 1100%
0.01 to 600 s
1 to 9999 s
900% to 1100%
900% to 1100%
0.1% to 10%
0, 100 to 102, 111, 112,
121, 122, 200 to 202,
211, 212, 221, 222
0
1
2
8
9, 90 to 96
PID gain tuning end
Equivalent time constant T (s)
Timeout time after the maximum slope (s)
(Pr.1214)
Description
Set the time after the PID gain tuning starts until a
timeout error occurs.
Set the step manipulated amount when using the
step response method to perform the PID gain
tuning.
Set the cycle for sampling of measurement values
when using the step response method to perform
the PID gain tuning.
Set the time after the measurement of the
maximum slope until the completion of the tuning
when using the step response method to perform
the PID gain tuning.
Set the upper limit value of the two-position output
when using the limit cycle method to perform the
PID gain tuning.
Set the lower limit value of the two-position output
when using the limit cycle method to perform the
PID gain tuning.
Set the hysteresis of the set point when using the
limit cycle method to perform the PID gain tuning.
Select the target loop, method, and control
adjustment method for the PID gain tuning.
PID gain tuning function disabled
PID gain tuning start
During PID gain tuning (read only)
PID gain tuning forced end
Tuning error (read only)
Step manipulated amount
(Pr.1212-1000)
Time
Measured value
variation range Y
Time
5. PARAMETERS
5.11 (A) Application parameters
1
2
3
4
5
6
7
8
9
10
437