Homing - Festo CPX Series Manual

3. Drive functions

3.2.2 Homing

3−36
For drives with incremental measuring systems, homing must
have been carried out before a positioning task can be done.
Homing can be carried out in each supported operating mode
except for parametrising mode.
The drive references with respect to a stop or, as a special
case, the current position. Reaching the stop is detected
when the piston comes to a standstill. Here, the possibility
that this standstill was caused by a lack of air pressure must
be ruled out.
Since the axis zero point for pneumatic axes must fundamen
tally be placed at the cylinder zero point, the drive (as op
posed to electric drives, for example) does not automatically
move to this zero point.
For a description of the homing methods, see section 3.2.4.
General homing information
The axes lose their reference:
when switched off, reset, etc.
possibly when there are errors in the sensor interface
or axis string
when homing is started again.
If the drive has a position measuring system with an abso
lute encoder, homing is not possible. An edge at the
CPOS.HOME input leads to a fault. No movement is in
itiated.
Festo P.BE−CPX−CMA X−CONTROL−EN en 0908NH