G90 Absolute Dimensions or Absolute Programming is Modal G-code. Siemens Sinumerik provides AC (non-modal absolute dimensions) command to access individual axis absolute position.
Read full article Sinumerik Absolute Dimensions G90 Modal and AC Non-modal Command.
Absolute Dimensions (Absolute Programming)
With Absolute dimensions or Absolute programming, the programmed position always refer to the zero point of the currently valid coordinate system (workpiece-zero-point).
Following cnc program example shows the use of following Siemens Sinumerik commands,
- G90 Modal Absolute Dimensions command
- AC Non-modal Absolute Dimensions command
Absolute Dimensions Program Example
Sinumerik Mill Program
N10 G90 G0 X45 Y60 Z2 T1 S2000 M3 ; Modal Absolute dimensions active N20 G1 Z-5 F500 ; circular interpolation, circle center point in absolute dimensions. N30 G2 X20 Y35 I=AC(45) J=AC(35) N40 G0 Z2 N50 M30
As Non-modal absolute dimensions (AC) are possible for spindle positioning (SPOS, SPOSA) and interpolation parameters (I, J, K).
So this program use AC non-modal absolute dimensions command to access circle center point dimensions.
