Lenze 8615E - Manual (Page 78)

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4.4.2 Manual adjustment
If, for technical reasons, the above described automatic adjustment
in idle running is not possible or too inaccurate, you can measure
the motor speed by hand and calculate the required feedback gain.
Proceed as follows:
•
Activate the closed-loop speed control (C005) with pilot control
of the output frequency by the controller reference
(C238 = -1-).
•
If possible, enter 100% set-value. If the set-value is smaller, the
obtainable adjustment result is normally less precise.
•
Enable the controller and wait for the acceleration.
Set under C074 the influence of the PI controller such that the
slip occuring during operation can be controlled.
•
Measure the motor speed.
•
Calculate the required feedback gain according to the following
equation:
Required gain = active gain
measured speed
desired speed
⋅
•
Enter the calculated value after selecting the suitable feedback
input (C025) under C027.
4.5 Setting of the controller parameters
With the setting of the controller parameters, you adapt the PI
controller to the drive. This adjustment is necessary after the auto-
adjustment as well as after the manual adjustment. Proceed as
follows:
•
Increase the gain of the PI controller under code C070 until the
drive starts to oscillate.
•
Then reduce this value by 10%.
•
If there should be no oscillation with a gain of 10, reduce the
adjustment time under C071, until the drive starts to oscillate.
•
Then reduce the gain by 10%.
•
If the system already oscillates with the factory setting, increase
the adjustment time, until the drive runs smoothly.
Code Parameter Meaning Acceptance
C070 1.0
0.01...300 Gain of the PI controller ON-LINE
C071 0.10s
0.01...100s Adjustment time of the PI controller ON-LINE