ABB ACSM1 Manual page 72

72
Actual position correction
The purpose of the actual position correction is to compare the difference between
62.16 PROBE1 POS
triggering conditions are fulfilled. If there is a deviation, a corresponding correction is
carried out on signal
position profile generator parameters.
Note: Probe 1 settings must always be used for the actual position correction.
This configuration also works with the estimated position besides the encoder
position.
Example:
The following figure presents a roll-over application. The motor rotates a round table.
There is a mechanical gear between the motor and load. The gear is prone to
produce some drift on the load side. In order to compensate this drift, actual position
correction is used. A proximity switch is located on the load side at 90°.
Encoder DI1
Parameter
60.05 POS UNIT
62.14 CYCLIC CORR
MODE
62.15 TRIG PROBE1
60.02 POS AXIS MODE (1) Rollover
62.16 PROBE1 POS
Drive control and features
and the actual encoder position at the moment when the
1.12 POS
ENCODER MOTOR GEARBOX
M
3~
Setting
(1) Degree
(1) Cor Act Pos
(1) ENC1 DI1 _–
90°
ACT. The required transition is determined by the
LOAD
PROXIMITY SWITCH
90°
Information
All position values are in degrees
Actual position correction
Rising edge of encoder 1 digital input DI1.
Source of the actual position latching command
(proximity switch signal source)
Positioning is between 0 and 1 revolutions, ie, after
360°, the position calculation starts from 0° again.
Reference position for the actual position probe