Automatic Setting Of The Absolute Value Offset At Homing; Notes - Baumuller b maXX BM3000 Operating Manual

4.8
Operating Modes

4.8.3.6 Automatic setting of the absolute value offset at homing

Applications using absolute encoders, automatically copy the absolute value offset (M0-
Offset) to the corresponding parameters (Z137.5–, Z137.6–) at the end of homing. Pa-
rameter
The absolute value offset is the shift between the encoder coordinate system (the abso-
lute encoder actual value as read from absolute value encoder) and the position coordi-
nate system redefined by homing (machine coordinate system). This absolute value
offset is considered at initialization of the encoder. This way, a positioning coordinate sys-
tem occurs, which is the same, as it would be after homing.
Encoder
coordinates
Position
coordinates
Figure 192:

4.8.3.7 Notes

Switch wiring The end and reference switches can be wired as closers or openers. The type of wiring
can be adjusted in the drive using the configuration of the digital inputs. Wiring as an
opener is recommended for safety reasons (detection of wire breaks).
Limit switch The hardware or software limit switches do not limit the traversing range during the hom-
ings!
The limit switches must be designed so that they cannot be overridden. The option to
leave the switching mode "actuated" with the negative limit switch should only be avail-
able in positive direction and only in negative direction with positive limit switch.
Problem during If homing is not completed after the reference switch is reached (response through Bit 10
Homing of
ing window (Z121.5–). The drive must be in the positioning window for the period of po-
sitioning window time that was set after the home position has been reached. The
positioning window may be adjusted too small so that this requirement cannot be met.
Reproducibility To reach identical home positions, the following conditions must be met:
m The homing speeds, acceleration, deceleration and encoder offset may not be
m The homing speed must be reached in Phase 1.
586 Parameter manual b maXX BM3000
Document no.: 5.12001.07
of 820
Z120.2–
Homing Mode, bit 6 activates this behavior.
0
Absolute value offset
Z108.3–
Status word does not occur), this may be due to the settings for the position-
changed after the one-time adjustment.
0
M0 offset
Reference point
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