Siemens SINUMERIK 840D sl, Function Manual

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Detailed description
2.3 Reference point appraoch from part program (G74)
Basic logic functions: Reference Point Approach (R1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
11
Aborting 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 the status "Not referenced":
DB31, ... DBX60.4 (referenced / synchronized 1)
DB31, ... DBX60.5 (referenced / synchronized 2)
2.3 Reference point appraoch from part program (G74)
Referencing of machine axes can be activated for the first time or repeated from the part
program
Referencing must be repeated, for example, after:
• converting the actual value of the machine axis:
PRESETON
function
• Machine axis is parked:
DB31, ... DBX1.5 (Position measuring system 1) = 0
DB31, ... DBX1.6 (Position measuring system 2) = 0
• DB31, ... DBX2.1 (servo enable) = 0
• Exceeding the encoder limit frequency of the position measuring system
Programming
Syntax
G74
Machine axis { Machine axis }
Function
Machine axes can be referenced from a part program with part program instruction
G74
Parameter:
Machine axes
The name of the machine axis must be specified. The machine axis must be a channel axis
of the channel in which the part program is processed.
Effective:
G74
is non-modal.
Special points to be noted
G74
must be programmed in a separate part program block.