
B-63323EN-1/03 4.REFERENCE POSITION ESTABLISHMENT
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4.2 SETTING THE REFERENCE POSITION WITHOUT DOGS
General
On a machine tool equipped with an absolute-position detector, this
function makes a movement by jog feed to a point near a reference
position specified for each axis, then sets a machine reference position
in reference position return mode without using the deceleration signal
for reference position return.
With this function, the machine reference position can be set at a given
position without installing the limit switch for deceleration for
reference position return.
Basic Procedure for Setting the Reference Position Without Dogs
(1) Feed the tool, along the axis for which the reference position is to
be set, by manual continuous feed in the reference position return
direction. Stop the tool near the reference position, but do not
exceed the reference position.
(2) Enter manual reference position return mode, then set 1 for the
feed axis direction selection signal (for the positive or negative
direction) for the axis.
(3) The CNC positions the tool to the nearest grid line (based on
one-rotation signals from the position detector) in the reference
position return direction specified with bit 5 (ZMI) of parameter
No. 1006. If parameter GRD (bit 6 of parameter No. 1006) is 1,
parameter APZ (bit 4 of parameter No. 1815) automatically
becomes 1, causing the absolute-position detector to memorize
that point as the reference position. A reference position, once set,
is held even if the power is turned off, so that reference position
setting need not be repeated when the power is turned on next.
(4) The CNC checks that the tool is positioned to within the in-
position area, then sets the completion signal for reference
position return and the reference position establishment signal to
1.
The timing chart for the basic elements constituting steps (2) to (4) is
shown below.