Siemens SINUMERIK 840D sl Function Manual page 1589

2.6.6 Reference point approach with absolute encoders
Traversing movement release
If for a mchine axis with adjusted absolute value encoder as active measuring system,
reference point traversing is activated (manual in the mode JOG-REF or automatic according
to part program instruction G74), the machine axis travels depending on the parameterized
release traversing movement.
MD34330 $MA_REFP_STOP_AT_ABS_MARKER = <Value>
Value
0
1
2.6.7 Automatic encoder replacement detection
Function
Automatic encoder replacement detection is required for absolute encoders in order to detect
if the encoder has been replaced and therefore needs to be readjusted.
The NC reads the encoder-specific serial number of the encoder from the drive every time
the control is powered up. If the serial number has changed the NC resets the encoder
status to "Encoder not calibrated".
MD34210 $MA_ENC_REFP_STATE = 0
The status of the measuring system is indicated as "Not referenced":
DB31, ... DBB60.4 / 60.5 (referenced/synchronized 1/2) = 0
Basic logic functions: Reference Point Approach (R1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Meaning
Traversing is enabled.
When reference point approach is initiated, the machine axis moves to the reference point
position. Reference point approach is completed when the reference point position is
reached.
Traversing is not enabled.
After the activation of the reference point travel, the machine axis does not travel and the
reference point travel is immediately completed.
2.6 Referencing with absolute value encoders
Detailed description
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