Siemens Sinumerik 840D sl Programming Manual page 52

Motion commands
3.2 Defining the input modes of the coordinate values
Example
N1000 G51.1 X... Y... Z...
...
...
...
...
G50.1 X... Y... Z..
Required machine data
G51.1 uses the channel-specific basic frame [1]. Hence, MD28081
$MC_MM_NUM_BASE_FRAMES > = 2 is to be set.
Mirroring with reference to a single axis in a specified plane
The following commands can change if the mirroring is used on one of the axes in the
specified plane as described below:
Table 3- 6
Command
Circular interpolation
Cutter radius compensation
Coordinate rotation
Commands for reference point approach and for changing the coordinate system
The G27, G28 and G30 functions as well as commands related to the coordinate system
(G52 to G59, G92, etc), should not be used when mirroring is active.
52
; Activate mirroring
; All the axis positions mirrored in the following
; blocks are mirrored at the mirroring axis programmed
; in N1000
;
;
;
; Deselection of programmable mirroring
Individual axes in specified plane
Explanation
G02 and G03 are exchanged mutually
G41 and G42 are exchanged with each other
The "clockwise" (CW) and "counter-clockwise" (CCW) directions of
rotation are exchanged mutually.
Programming Manual, 06/09, 6FC5398-7BP10-1BA0
ISO Milling