Siemens SINUMERIK 840DE SL - Page 1457

Detailed Description
2.4 Referencing with incremental measurement systems
Reference Point Approach (R1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
2-17
Phase 3: Sequence
The machine axis moves at the assigned reference point positioning velocity:
MD34070 $MA_REFP_VELO_POS (reference point positioning velocity)
from the encoder zero mark detected in Phase 2 to the reference point.
The path s
ref
to be covered is calculated from the sum of the reference point distance plus
reference point offset:
MD34080 $MA_REFP_MOVE_DIST (reference point distance)
MD34090 $MA_REFP_MOVE_DIST_CORR (reference point offset)
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Fig. 2-9 Reference point position
When the reference point is reached the machine axis is stopped and the actual value
system of the machine axis is synchronized with the reference point value specified by the
PLC user program.
Reference position of machine axis = MD34100$MA_ REFP_SET_POS[ n ] (reference point
value [ n ])
The reference point value is specified by the PLC user program by means of:
DB31, ... DBX2.4/.5/.6/.7 (reference point value 1/2/3/4)
In so doing, the NC assumes the reference point value that was selected by the PLC user
program when the reference cam was reached in Phase 1:
DB31, ... DBX12.7 (deceleration of reference point approach) = 1
The machine axis is now referenced. To identify this, the NC sets the appropriate interface
signal based on which measuring system is currently active:
DB31, ... DBB60.4 / .5 (referenced/synchronized 1/2) = 1