Siemens SINUMERIK 840D sl Function Manual page 1553

Detailed description
2.1 Axisspecific referencing
In axis-specific reference point approach, reference point approach must be initiated
individually for each machine axis that is to be referenced.
Selection of mode and machine function
Before starting reference point approach of the machine axes, you must first place the
relevant mode group in JOG or MDA mode:
DB11, ... DBX0.2 (JOG mode)
DB11, ... DBX0.1 (MDA mode)
Then the machine function REF (reference point approach) must be selected:
DB11, ... DBX1.2 (Machine function REF)
Start reference point approach
In axis-specific reference point approach, each machine axis must be started individually.
Reference point approach is started with the axis-specific traversing keys:
DB31, ... DBX4.6 (Traversing key minus)
DB31, ... DBX4.7 (Traversing key plus)
Direction enable
To avoid faulty operation, the direction release must be parameterized:
MD34010 $MA_REFP_CAM_DIR_IS_MINUS (approach reference point in minus direction)
The direction enable specifies which traversing key starts the reference point approach:
Value
0
1
Basic logic functions: Reference Point Approach (R1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Meaning
Reference point approach in plus direction
Reference point approach in minus direction
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