
7. COORDINATE VALUE AND
DIMENSION
B–63122EN/01
NC FUNCTION
52
Conversion of inch and metric input can be commanded by the G code
command.
G20 : Inch input
G21 : Metric input
Whether the output is in inch system or metric system is parameter-set
when the machine is installed.
Command G20, G21 at the head of the program.
Inch/metric conversation can also be done by MDI setting.
The contents of setting data differs depending on whether G20 or G21 is
commanded.
Numerals can be input with decimal points. Decimal points can be used
basically in numerals with units of distance, speed, and angle. The
position of the decimal point is at the mm, inch, deg position.
Use parameters to select input method; whether to input by pocket
calculator type input, or by the former type decimal point input.
Program command Pocket calculator type
decimal point input
Former type decimal
point input
×1000 1000mm 1mm
×1000. 1000mm 1000mm
A linear axis refers to an axis moving linearly, and for it values are
specified in mm or inches.
A rotation axis refers to a rotating axis, and for it values are specified in
degrees.
For rotation axes, note the following:
Inch-metric switching is not performed.
The machine coordinate system is always normalized to the range
from 0° to 360°.
The rotation axis roll-over function rounds the absolute coordinate value
and relative coordinate value of a rotation axis to a coordinate value
within one rotation. This prevents coordinate values to overflow.
In an incremental command, the specified value is regarded as the amount
of travel.
In an absolute command, the specified value is rounded to within one
rotation. The resulting coordinate value is used as the end point. A
parameter is used to specify whether to determine the move direction by
the sign of the specified value or by the move distance (the shortest move
distance to the end point is selected).
CAUTION
This function is invalid in T axis and C axis
7.2
INCH/METRIC
CONVERSION
(G20, G21)
7.3
DECIMAL POINT
INPUT/POCKET
CALCULATOR TYPE
DECIMAL POINT
INPUT
7.4
LINEAR AXIS AND
ROTATION AXIS
7.5
ROTATION AXIS
ROLL–OVER
FUNCTION