Siemens SINUMERIK 840D sl Programming Manual page 87

Further information
Applications
The "Programmable tool offset" function is especially interesting for ball mills and milling tools
with corner radii as these are often calculated in the CAM system to the ball center instead of
the ball tip. However, generally the tool tip is measured when measuring the tool and stored
as tool length in the compensation memory.
System variables for reading the current offset values
The currently effective offsets can be read with the following system variables:
System variables
$P_TOFFL [<n>]
$P_TOFF [<geometry axis>]
$P_TOFFR
$AC_TOFFL[<n>]
$AC_TOFF[<geometry axis>]
$AC_TOFFR
Note
The system variables $AC_TOFFL, $AC_TOFF and AC_TOFFR trigger an automatic
preprocessing stop when reading from the preprocessing context (NC program).
Fundamentals
Programming Manual, 09/2011, 6FC5398-1BP40-2BA0
5.8 Programmable tool offset (TOFFL, TOFF, TOFFR)
Meaning
with 0 ≤ n ≤ 3 Reads the current offset value of TOFFL (for
n = 0) or TOFFL[1...3] (for n = 1, 2, 3) in the
preprocessing context.
Reads the current offset value of
TOFF[<geometry axis>] in the
preprocessing context.
Reads the current offset value of TOFFR in the
preprocessing context.
with 0 ≤ n ≤ 3 Reads the current offset value of TOFFL (for
n = 0) or TOFFL[1...3] (for n = 1, 2, 3) in the
main run context (synchronized actions).
Reads the current offset value of
TOFF[<geometry axis>] in the main run
context (synchronized actions).
Reads the current offset value of TOFFR in the
main run context (synchronized actions).
Tool offsets
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