Product manual

IP 266 Machine Data, Modes and Traversing Programs
Figure 5-9. Backlash Outside the Control Loop (compensatible)
Backlash
M : Motor T: Tachogenerator : Incremental encoder
M T
T
T
M
M
Reversal of direction
Displayed actual value increases
Backlash
Axis movement around the backlash
Actual value display remains constant
although the encoder is generating
pulses axis passes through the back-
lash
After traversing the path = backlash
value, the actual value display shows the
actual value to be on the decrease
Conditions for correct operation:
• Positive mechanical coupling between drive and slide
- when a distance > backlash value is traversed.
• Reference point has been approached
- when the distance to zero mark recognition is > backlash value.
• Following a drive movement within the permissible play of the backlash
(follow-up mode), the conditions for correct operation are no longer fulfilled.
A positive mechanical coupling must be reestablished between the drive and
the slide.
• Overswing can also result in loss of positive mechanical coupling. This is
possible when the overswing movement caused the distance traversed to be
less than the backlash. Overswing can be avoided by reducing the Kv factor.
EWA 4NEB 812 6057-02 5-19