Pid Gain Tuning Error; Fine Adjustment After Pid Gain Tuning - Mitsubishi Electric FR-F800 Instruction Manual

(A) Application parameters
PID gain tuning error
• When the read value of Pr.1219 or the PID gain tuning status monitor display is "9, 90 to 96", tuning has not been properly
completed due to a tuning error. Remove the cause of the tuning error, and perform tuning again.
Monitor
Error definition
value
Termination of tuning due
9 to activation of an inverter
protective function
90 Input upper limit error
91 Input lower limit error
92 Deviation limit error
93 Timeout error
94 Calculation error
95 Setting error
96 PID mode error
Fine adjustment after PID gain tuning
• If fine adjustment is required after completion of PID gain tuning, adjust the proportional band (Pr.129 or Pr.756), integral
time (Pr.130 or Pr.757), and differential time (Pr.134 or Pr.758).
Status of measurement values
The response is fast, but vibrations are observed.
Measured value[%]
Set point[%]
Optimal
Measured value[%]
Set point[%]
Response is slow.
Measured value[%]
Set point[%]
NOTE
• When the differential operation is used, adjust the differential time (Pr.134 or Pr.758) while checking the stability and the
response. (Increasing the differential time makes the differential effect larger, and decreasing the differential time makes the
differential effect smaller.)
398
PARAMETERS
Cause of tuning error
An inverter protective function is activated.
The measured value is higher than the PID upper limit
(Pr.131 or Pr.1143).
The measured value is lower than the PID lower limit
(Pr.132 or Pr.1144).
The deviation exceeded the PID deviation limit (Pr.553 or
Pr.1145).
Tuning is not terminated within the time set in Pr.1211 after
the start of PID gain tuning.
The tuning calculation is inconsistent.
• PID control is disabled during tuning.
• The PID control setting has been changed during tuning.
• In the limit cycle method, the Pr.1215 setting is equal to or
lower than the Pr.1216 setting.
• PID gain tuning has been started during automatic
switchover or pre-charge operation.
• A stall prevention or regeneration avoidance operation
occurred during PID gain tuning.
• A condition for output shutoff by the SLEEP function was
satisfied during PID gain tuning.
• Frequency fluctuation occurred because of the frequency
jump, maximum frequency, or minimum frequency during
PID gain tuning.
• Increase the proportional band (Pr.129 or Pr.756).
• Increase the integral time (Pr.130 or Pr.757).
Time
—
Time
• Decrease the proportional band (Pr.129 or Pr.756).
• Decrease the integral time (Pr.130 or Pr.757).
Time
Adjustment method
(Smaller proportional effect)
(Smaller integral effect)
(Larger proportional effect)
(Larger integral effect)
Corrective action for error
Remedy the cause. (Refer to
535.)
Change the Pr.131 or Pr.1143
setting as appropriate.
Change the Pr.132 or Pr.1144
setting as appropriate.
Change the Pr.553 or Pr.1145
setting as appropriate.
Change the Pr.1211 setting as
appropriate.
In the step response method,
change the Pr.1212 and Pr.1213
settings as appropriate.
In the limit cycle method, change
the Pr.1217 setting as appropriate.
• Enable PID control.
• Change the Pr.1215 and Pr.1216
settings as appropriate.
Change the setting of each function
as appropriate.
page