HEIDENHAIN iTNC 530 (60642x-04) User Manual

Page 385

HEIDENHAIN iTNC 530

385

.3 Miscellaneous functions f

r coor

dinat

data

Behavior with M92—Additional machine datum

If you want the coordinates in a positioning block to be based on the

additional machine reference point, end the block with M92.

Effect
M91 and M92 are effective only in the blocks in which they are

programmed.
M91 and M92 take effect at the start of block.

Workpiece reference point
If you want the coordinates to always be referenced to the machine

datum, you can inhibit reference-point setting for one or more axes.
If reference-point setting is inhibited for all axes, the TNC no longer

displays the SET DATUM soft key in the Manual Operation mode.
The figure shows coordinate systems with the machine datum and

workpiece datum.

M91/M92 in the Test Run mode
In order to be able to graphically simulate M91/M92 movements, you

need to activate working space monitoring and display the workpiece

blank referenced to the set reference point (see "Showing the

In addition to the machine datum, the machine tool builder

can also define an additional machine-based position as a

reference point.
For each axis, the machine tool builder defines the

distance between the machine datum and this additional

machine reference point. Refer to the machine manual for

more information.

Radius compensation remains the same in blocks that are

programmed with M91 or M92. The tool length, however,

is not compensated.
If you program M3 or M4 together in a block with M92,

then always program M3 before M92.