Re-Setting The Machine Datum - HEIDENHAIN iTNC 530 Service Manual

17.1.6 Re-Setting the Machine Datum

As the machine datum (machine reference) refers to the scale reference point, a resetting might
be necessary after removing and mounting of scales, scale tapes or angular encoders.
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Note
With simple 3-axis machines, it is often not necessary to set the machine datum again. It is
sufficient to the check the software limit-switches and to set them again, if necessary. If
you have any questions, please contact your machine tool builder for more information!
It is indispensible to set the machine datum, but mostly machine tools with tool changers,
tilting axes, etc. are concerned.
Always tro to mount the scale as exactly as possible to its original position!
Set the display to REF. --> You can now see the current axis position referring to the
machine datum.
Set the position display step (MP 7290.x) to the highest resolution.
Reference the axis concerned.
Position the machine datum or a machine's reference point defined by the machine
manufacturer (e.g., reference hole, reference stud). --> Ask the machine manufacturer!
Note
If necessary, the traverse range (software limit switch) has to be expanded!
(The software limit switches are defined as of MP 910.x. It is also possible that the operator
has limited the traverse range even further.)
Write down the displayed REF value (if necessary, abstract the value defined by the machine
manufacturer) and invert the result.
Add the value to the value entered in MP 960.x for the axis concerned.
Enter the sum in MP960.x.
Check whether the reset machine datum is correct (e.g., with M91)!
If required, reset the traverse range to the original value.
HEIDENHAIN Service Manual iTNC 530