Phase 3: Travel to the reference cam with referencing

Parameter definition of phase 3

P-AXIS-00084
(homing_without_zero_pulse)

With or without zero pulse

P-AXIS-00158 (ref_richt)

Referencing direction

P-AXIS-00218 (vb_reflow)

Slow referencing speed
e.g. 15000 [μm/s]

Start of phase 3

Phase 3 is started automatically when phase 2 has been successfully ended and the machine axis is no longer on the reference cam.

The search for the reference position can take place by means of

Homing with zero pulse

Phase 3: Travel to the reference cam with referencing 1:
Figure 0-5: Homing in three phases with referencing to the reference cam with zero pulse

Homing with reference cam

Phase 3: Travel to the reference cam with referencing 2:
Figure 0-6: Homing in three phases with referencing to the reference cam without zero pulse
Phase 3: Travel to the reference cam with referencing 3:

With this parameter definition, referencing takes place at the positive edge of the cam signal in the third phase, i.e. during travel to the cam. Referencing takes place by actuation of the cam switch in the third phase of homing. In this process, the accuracy of referencing is defined by the axis speed (vb_reflow) in phase 3 and by the sampling time because the position is only imported at the discrete times and the position value is not latched as in the case of zero pulse evaluation.

This process is applied to stepper motor applications without an incremental encoder, for example. An accuracy which is adequate in most cases can be achieved here if P-AXIS-00218 (vb_reflow) is initialised so that the motor moves at one increment per sampling cycle in the the third phase.

This process is also applied to separable drives (rack-and-pinion), for which the zero pulse signal is normally not used.