Reference Point Appraoch From Part Program (G74) - Siemens SINUMERIK 840D Function Manual

The status of channel-specific reference point approach is indicated by the channel with:
DB21, ... DBX33.0 (referencing active)
Referencing status
The referencing status of the machine axis is reset with the start of the reference point
approach:
DB31, ... DBX60.4 (referenced/synchronized 1)
DB31, ... DBX60.5 (referenced/synchronized 2)
Completion of reference point approach
As soon as channel-specific reference approach has been successfully completed for all
machine axes involved, this is acknowleged with:
DB21, ... DBX36.2 (all axes with obligatory reference point are referenced)
Cancellation of reference point approach
In channel-specific reference point approach the machine axis is traversed in the channel to
which that axis is currently assigned as channel axis.
For aborting the reference point approach either mode group reset or channel reset for the
corresponding channel must be activated:
DB11, ... DBX0.7 (mode group reset)
DB21, ... DBX7.7 (channel reset)
All machine axes for which the reference point approach is not yet successfully completed
when the action is cancelled remain in status "Not referenced":
DB31, ... DBX60.4 (referenced/synchronized 1)
DB31, ... DBX60.5 (referenced/synchronized 2)
10.4

Reference point appraoch from part program (G74)

Function
With command G74, machine axes can be referenced from a part program or synchronized
action either for the first time or again.
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
10.4 Reference point appraoch from part program (G74)
R1: Referencing
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