6. AXIS SPECIFICATIONS PARAMETERS
6.2 Zero Point Return Parameters
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6.2 Zero Point Return Parameters
After setting up the parameter (PR) listed in the table, turn OFF the NC power. To validate the parameter,
turn ON the power again.
(SETUP PARAM 2. 3/8)
# Items Details Setting range (unit)
2025 G28rap G28 rapid
traverse rate
Set up a rapid traverse rate for dog type reference
point return command.
1 to 999999
(mm/min)
2026 G28crp G28 approach
speed
Set up the speed of approach to the reference point in
the reference point return command. This speed is
attained after the system stops with deceleration by
dog detection.
Note) The G28 approach speed unit is (10°/min) only
when using the Z-phase type encoder (#1226
aux10 bit3=1) for the spindle/C-axis reference
point return type. The same unit is used for
both the micron and sub-micron specifications.
1 to 60000 (mm/min)
2027 G28sft Reference
point shift
distance
Set up the distance from the electrical zero-point
detection position to the actual machine reference
point during reference point return.
Note) When #1240 set12 (bit2) is ON, a
magnification (C: 10-fold) corresponding to the
input setting unit (#1003 iunit) will be applied
on the setting value.
0 to 65535 (µm)
2028 grmask Grip mask
amount
Set up a distance where the grid point is ignored when
near-point dog OFF signals are close to that grid point
during reference point return.
The grid mask is valid by one grid.
0 to 65535 (µm)
Even when the least
setting increment is
0.1µm, set up the
value in units of µm.
2029 grspc Grid interval Set up a detector grid interval.
Generally, set up the value equal to the ball screw
pitch. However, if the detector grid interval is not
equal to the screw pitch when measured with a linear
scale, set up the detector grid interval.
To reduce the grid interval, use its divisors.
To use 0.001 mm as minimum setup units, set up the
negative value.
Example) Setup value
−1 → 1.000 mm (°)
−1 → 0.001 mm (°)
Even when the least setting increment is 0.1µm, it will
be 0.001mm if a negative value is set.
−32767 to 999 (mm)
