5-124
F codes
E codes
C codes
P codes
H codes
A codes
b codes
r codes
J codes
d codes
U codes
y codes
Chap. 5 FUNCTION CODES
J03 to J06 PID Control (P (Gain), I (Integral time), D (Differential time), Feedback filter)
P gain (J03) Data setting range: 0.000 to 30.000 (times)
J03 specifies the gain for the PID processor.
P (Proportional) action
An operation in which the MV (manipulated value: output frequency) is proportional to the deviation is called P action,
which outputs the MV in proportion to deviation. However, the MV alone cannot eliminate deviation.
Gain is data that determines the system response level against the deviation in P action. An increase in gain speeds up
response, but an excessive gain may oscillate the inverter output. A decrease in gain delays response, but it stabilizes
the inverter output.
I integral time (J04)
Data setting range: 0.0 to 3600.0 (s), 0.0 means that the integral component is ineffective.
J04 specifies the integral time for the PID processor.
I (Integral) action
An operation in which the change rate of the MV (manipulated value: output frequency) is proportional to the integral
value of deviation is called I action, which outputs the MV that integrates the deviation. Therefore, I action is effective
in bringing the feedback amount close to the commanded value. For the system whose deviation rapidly changes,
however, this action cannot make it react quickly.
The effectiveness of I action is expressed by integral time as parameter, that is J04 data. The longer the integral time,
the slower the response. The reaction to the external disturbance also becomes slow. The shorter the integral time, the
faster the response. Setting too short integral time, however, makes the inverter output tend to oscillate against the
external disturbance.
D differential time (J05)
Data setting range: 0.00 to 600.00 (s), 0.00 means that the differential component is ineffective.
J05 specifies the differential time for the PID processor.
D (Differential) action
An operation in which the MV (manipulated value: output frequency) is proportional to the differential value of the
deviation is called D action, which outputs the MV that differentiates the deviation. D action makes the inverter quickly
react to a rapid change of deviation.
The effectiveness of D action is expressed by differential time as parameter, that is J05 data. Setting a long differential
time will quickly suppress oscillation caused by P action when a deviation occurs. Too long differential time makes the
inverter output oscillation more. Setting short differential time will weakens the suppression effect when the deviation
occurs.
To Next Page
Loading...
