Festo EMCA-EC-67 CO Series, Описание

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10 Control via FHPP
Festo – EMCA-EC-C-HP-EN – 2017-11e – English 155
10.4 Homing mode
10.4.1 Homing
In homing, the reference point of the dimensional reference system is determined. All points of refer­
ence and drive limits of the dimension reference system refer directly or indirectly to the reference
point. The reference point is the absolute reference point for the axis zero point
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page 141. For the
record and direct mode, valid homing is always required. The homing sequence always depends on the
homing method and homing parameters
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page 160. The reference point is determined as follows:
– Reference switch: evaluation of the trailing switch edge
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page 158
– Limit switch: evaluation of the trailing switch edge
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page 158
– Stop: evaluation of the stop detection
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page 159
– Current position: evaluation of the current actual position
– Reference/limit switch with index: evaluation of the index from the encoder
With the homing method “Stop”, travel to the axis zero point is always at positioning speed. For all
other homing methods, travel to the axis zero point is optional. After valid homing, the EMCA remains
controlled at the reference point or the axis zero point.
Note
Loss of homing
– When the homing method is changed
– When the dimension reference system is changed
– Single-turn absolute encoder:
If there is no power supply or after a “Reset device” reset (PNU 127.3 = 10
h
), hom­
ing is lost.
– Multi-turn absolute encoder:
If there is no power supply or it is switched off, homing is lost when the internal
battery is discharged.
For additional information
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Description for “Integrated drive with bus interface,
EMCA-EC-SY-...”.
Software end positions
The software end positions are deactivated with the start of homing and reactivated after
a valid homing.