Parallel Axes (G17, G18, G19); Rotation Of The Coordinate System (G68, G69) - Siemens SINUMERIK 808D Programming And Operating Manual

Selection of plane:
● The Plane X-Y (G17) is selected automatically after activating the control system.
● The command for moving an individual axis can be specified independently of the plane selection by G17, G18 or G19.
Thus for instance, the Z axis can be shifted by specifying "G17 Z ....;".
● The plane in which the tool radius compensation is executed with G41 or G42 is defined by specifying G17, G18 or G19.
4.3.1.8

Parallel axes (G17, G18, G19)

An axis located parallel to one of the three main axes of the coordinate system can be activated by using the function G17
(G18, G19) <Axis name>.
The three main axes are, e.g., X, Y and Z.
Example
G17 U0 Y0
The parallel axis U is activated when the X axis in the G17 plane is replaced.
Explanations
● An associated parallel axis can be defined for each geometry axis with machine data
$MC_EXTERN_PARALLEL_GEOAX[ ].
● Only geometry axes from a plane defined with (G17, G18, G19) can be replaced.
● On replacing the axes, normally all shifts (frames) - with the exception of the handwheel and external shifts - are deleted.
The following machine data is to be set to prevent the values from being deleted:
Shifts (frames)
$MN_FRAME_GEOAX_CHANGE_MODE
● Details are available in the machine data description.
● Alarm 12726 "Impermissible plane selection with parallel axes" is output if a main axis is programmed along with the
associated parallel axis with a command for selecting the plane.
4.3.1.9

Rotation of the coordinate system (G68, G69)

Properties of G68 and G69
A coordinate system can be rotated through the following G functions.
G function
G68
G69
G68 and G69 are modal G functions of the G group 16. G69 is set automatically on activating the control system and
resetting the NC.
The blocks containing G68 and G69 should not contain any other G functions.
The rotation of the coordinate system is called with G68 and deselected with G69.
104
Function
Rotation of the coordinate system
Deselection of Rotation of the coordinate system
G group
16
16
Programming and Operating Manual (ISO Turning/Milling)
01/2017