Siemens SINUMERIK 828D Function Manual page 1236

R1: Reference point approach
15.9 Referencing with absolute value encoders
Readjustment
Readjustment of the absolute encoder is required after:
• Gear change between load and absolute encoder
• Removal/installation of the absolute value encoder
• Removal/installation of the motor with the absolute value encoder
• Data loss in the static NC memory
• Battery failure
• Setting actual value (PRESETON)
NOTICE
The NCK can only detect a required readjustment during the following events:
•
•
•
Thereupon, the status of the absolute encoder is automatically reset by NCK to 0
(encoder not calibrated) (MD34210 = 0) and the following alarm is displayed:
Alarm 25022 "Axis <Axis identifier> Encoder <Number> Warning 0"
or when addressing the zero-mark monitoring (only systems with SIMODRIVE 611D):
Alarm 25020 "Axis <Axis identifier> Zero-mark monitoring of the active encoder"
In all other cases (e.g. PRESETON) it is the sole responsibility of the user, by resetting the
status to 0 (encoder not adjusted), to show the misalignment of the absolute value
encoder and to carry out a readjustment.
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)
1236
Gear change with change of gear ratio
Addressing the zero-mark monitoring
New encoder serial number after change of the absolute value encoder
WARNING
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions