Method 7: positive search direction
Method 11: negative search direction
Tab. 245 Sequence principle - homing to reference switch with zero pulse
Situation
Reaction
"Search direction" reference switch not detected
(rising edge)
Homing aborted with fault message.
Reference switch edge not detected (falling edge) Homing aborted with fault message.
Zero pulse within one motor revolution not detec-
ted
Homing aborted with fault message.
Distance "zero pulse - reference switch" too
short
Homing aborted with fault message.
"Search direction" limit switch detected
Limit switch monitoring is deactivated
"Opposite direction" limit switch detected
Homing aborted with fault message.
Stop detected
Homing aborted with fault message.
Tab. 246 Different sequence scenarios
4.4.3.7
Method -23/-27: positive/negative stop/limit switch with run to reference switch
The reference mark is found by the switching edge of the reference switch after identification of the
limit switch or the stop.
Sequence:
1. Search stop/limit switch: stop or rising edge of the limit switch is searched in search direction at
search velocity.
2. Search reference switch: reference switch is searched in opposite direction at search velocity.
3. Search reference switch edge: falling edge of the reference switch (rest position) is searched
again at creep velocity in the opposite direction.
4. Set reference mark: position of switching edge is taken as the reference mark.
5. Set axis zero-point: the axis zero-point is set with reference to the reference mark.
6. Report status: "homing status" is set.
Travel to the axis zero-point
è
4.4.3.10 Travel to axis zero-point.
Motion control
271
Festo — CMMT-ST-SW — 2019-02
Summary of Contents for CMMT-ST-SW
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