
B–63173EN–1/01
4. REFERENCE POSITION ESTABLISHMENT
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+J1, –J1, or ZR1
Grid
ZP1
ZRF1
Feedrate
Manual reference
position return
mode
FL rate
The following figure shows the positional relation between the reference
position and the point to which the tool is positioned by manual
continuous feed.
Grid
– direction
Position
after jog feed
+ direction
Reference position for reference position return in the negative direction
Reference position for reference position return in the positive direction
AB
A
B
To set the reference position without dogs, when the reference position
has not yet been established, the tool must be fed, in manual continuous
feed mode, in the reference position return direction at such a speed that
the servo position error exceeds the value set in parameter No. 1836. The
tool must cross the grid line corresponding to a one–rotation signal from
the position detector.
Section 4.1 explains how to calculate the servo position error.
To shift the reference position, the grid can be shifted by the distance set
in parameter No. 1850. The grid shift to be set in the parameter must not
exceed the reference counter capacity (parameter No. 1821).
It is possible to keep resetting a new grid point as a reference position,
with the above mentioned method, when the set reference position is
different from the true reference position. After setting the reference
position using the method given in (a), when the ZRn signal is turned ON,
it moves at a constant low speed to the next grid point and that point is
set as the new reference position. This operation can be repeated over
again allowing the true reference position to be set while changing it 1 grid
at a time.
Servo position error and
one–rotation signal
Grid shift
Reference position
resetting operation