Festo CMMT-ST-SW, Оригинальное руководство пользователя

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Method 23: positive search direction Method 27: negative search direction
Tab. 243 Sequence principle - homing to reference switch
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.
"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. 244 Different sequence scenarios
4.4.3.6 Method 7/11: positive/negative reference switch with zero pulse
The reference mark is found after identification of the reference switch by the first zero pulse of the
encoder.
Sequence:
1. Search reference switch: rising edge of the reference switch is searched in search direction at
search velocity.
2. Search reference switch edge: falling edge of the reference switch (rest position) is searched at
creep velocity in the opposite direction.
3. Search zero pulse: first zero pulse of the encoder is searched again at creep velocity in the oppos-
ite direction.
4. Set reference mark: position of the zero pulse 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
270 Festo — CMMT-ST-SW — 2019-02