Calibration By Entering A Reference Point Offset - Siemens SINUMERIK 840D Function Manual

R1: Referencing
10.9 Referencing with absolute encoders
● Battery failure
● Set actual value (PRESETON)
Note
The controller can detect a required readjustment of the absolute encoder only during the
following events:
● Gear change with change of gear ratio
● Addressing the zero-mark monitoring
● New encoder serial number after change of the absolute encoder
The controller then sets the status of the absolute encoder to "0":
MD34210 $MA_ENC_REFP_STATE = 0 (encoder not adjusted)
The following alarm is displayed:
Alarm 25022 "Axis <axis name> encoder <number> warning 0"
If the zero-mark monitoring responds, the following alarm is also displayed:
Alarm 25020 "Axis <axis name> zero-mark monitoring of active encoder"
In all other cases (e.g. PRESETON) it is the sole responsibility of the user to display the
misalignment of the absolute encoder by manually setting the status to "0" and to carry out
a readjustment.
10.9.2

Calibration by entering a reference point offset

Function
During adjustment by entering the reference point offset, the difference between the position
displayed on the operator interface and the true actual position in the machine is determined
and made known to the NC as reference point offset.
322
WARNING
Data backup
During the back-up of machine data of a machine A, the encoder status of the machine axis
(MD34210) is also backed up.
During loading of this data record into a machine B of the same type, e.g. in the context of
a serial start-up or after a case of maintenance, the referenced machine axes will be
automatically regarded as adjusted / referenced by the NC. It is the special responsibility
of the machine manufacturer / user to undertake a readjustment in such cases.
See also explanations regarding machine data:
MD30250 $MA_ACT_POS_ABS (absolute encoder position at the time of switch-off)
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA