Siemens SINUMERIK 840D sl Function Manual page 1585

2.6.4 Automatic calibration with probe
Function
In automatic adjustment with a probe, a known position in the machine is approached with
the machine axis from a part program. The position value is stored in the NC as a reference
point value. The position is reached when the probe switches, and the NC then calculates
the reference point offset from the difference between the encoder value and reference point
value.
Note
Part program for automatic adjustment
The part program for automatic adjustment using a probe must be created by the machine
manufacturer / user for the specific requirements of the machine.
Freedom from collision
Because actual-value-related monitoring is not active for the machine axes being referenced,
the machine operator must take special care to ensure that collisions do not occur in the
machine while the machine axes are being moved!
Part program
The part program for automatic adjustment of absolute encoders with probe must perform
the points listed below for each axis in the order indicated:
1. Approach the adjustment position of machine axis, which is detected from the probe
Basic logic functions: Reference Point Approach (R1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Note
Activate reference point offset permanently
The entered reference point offset (MD34090) will only be permanently active after
POWER ON - Reset.
If the machine axis is moved after the absolute encoder adjustment without an interim
POWER ON - Reset, the reference point offset entered in the machine data can be
overwritten, for example, within internal overrun corrections.
Checking the actual position
Following adjustment of the absolute encoder, we recommend that you verify the actual
position of the machine axis the next time you power up the controller (POWER ON).
response.
The position must be approached several times from the same direction, but at a velocity
which is gradually reduced on each approach, to ensure that the measured value
2.6 Referencing with absolute value encoders
Detailed description
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