ACU-RITE Micro-Line T - Manual (Page 16)

13 MICRO-LINE Reference Manual
OPERATION
Setting the Datum (Absolute Zero)
MICRO-LINE allows you to measure both absolute and incremental
dimensions. A dimension measured from the point you define as the
datum is an absolute dimension. A dimension measured from any other
point on your print is an incremental dimension.
Datum, also known as absolute zero or workpiece zero, is the reference
point from which
MICRO-LINE will base all of your part’s coordinates.
When the readout is in the ABS mode, it is actually measuring the dis-
tance from the datum to the machine axis’current position.
You will need to establish a datum for every job. Your datum may
already be identified on your print; if it isn’t, then establish a datum that
allows you to measure most of your part’s dimensions directly, with the
least number of calculations.
All of the dimensions in the drawing below are based from the datum.
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