Operating Instructions

Descriptions of Parameter Settings
Descriptions of Parameter Settings
201 | 443
Pr.
Explanation
Settings
Default
08-07
PID delay time
0.0 to 2.5 sec.
0.0
08-20
PID mode selection
0: Serial connection
1: Parallel connection
0
0: Use conventional PID control structure.
1: The proportional gain, integral gain and differential gain are independent. You can customize the P, I and D
value to fit your application.
Pr.08-07 determines the primary low pass filter time when in PID control. Setting a large time constant may slow
down the drive’s response speed.
PID control output frequency is filtered with a primary low pass function. This function can filter a mix of
frequencies. A long primary low pass time means the filter degree is high and a short primary low pass time means
the filter degree is low.
Inappropriate delay time setting may cause system oscillation.
PI Control:
Controlled only by the P action, so the deviation cannot be entirely eliminated. In general, to eliminate residual
deviations, use the P + I controls. When you use the PI control, it eliminates the deviation caused by the targeted
value changes and the constant external interferences. However, if the I action is too powerful, it delays the
response when there is rapid variation. You can use the P action by itself to control the loading system with the
integral components.
PD Control:
When deviation occurs, the system immediately generates an operation load that is greater than the load
generated only by the D action to restrain the deviation increment. If the deviation is small, the effectiveness of the
P action decreases as well. The control objects include applications with integral component loads, which are
controlled by the P action only. Sometimes, if the integral component is functioning, the whole system may
oscillate. In this case, use the PD control to reduce the P action’s oscillation and stabilize the system. In other
words, this control is useful with no brake function’s loading over the processes.
PID Control:
Use the I action to eliminate the deviation and the D action to reduce oscillation; then combine this with the P action
for the PID control. Use the PID method for a control process with no deviations, high accuracy, and a stable
system.