Lenze EVS9332xP - Manual (Page 57)

Function library
Positioning control
3.4.2 Machine parameters
3−29
l
EDSVS9332P−EXT DE 2.0
Stop!
Increasing the ratio between the position encoder and the motor shaft reduces the position
resolution information. This can have a negative effect on the stability of the control loop!
Example (refers to the previous safety information):
In the case of a quadruple evaluation of a position encoder with 1024 increments 4096 increments
are available. Angle of rotation of the motor shaft per encoder increment:
360°
4096 incr
+ 0.0879 ° + 0° 5.3Ȁ (5.3 phase minutes)
Ratio of the position encoder e.g. i = 128:
0.0879°
128 + 11.25° + 11° 15Ȁ (11 ° and 15 phase minutes)
The motor should rotate by 11
° to compensate an offset of one increment. A further increase of the
ratio would raise the "compensating path" of the motor.
Permanent slipping of a friction wheel running on the material web (= drive of the position encoder)
results in a faulty actual position value. A web break could accelerate the drive to high speeds due
to the missing actual position value.
Example:
The spindle drive mentioned in the previous example is driven with a separate position encoder
connected to the spindle (gearbox output side).
Settings as described under machine parameters but:
C1206 Polarity of position setpoint −0−: Not inverse
−1−: Inverse Reversal of traversing direction
C1207/1 Position encoder gearbox factor, numerator 32 Numerator corresponds to motor speed
C1207/2 Position encoder gearbox factor,
denominator 1 Denominator corresponds to encoder speed
C1208 Polarity − actual position −0−: Not inverse
−1−: Inverse If inverse" is selected, observe the QSP function notes.