Fagor CNC 8065 - Home Search (Axes and Spindles)

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Installation manual
CNC 8060
CNC 8065
9.
CONCEPTS.
(REF: 1402)
Home search.
9.6.1 Home search (axes and spindles).
Home search with a feedback system that does not have
distance-coded reference marks.
When the feedback system does not have distance-coded reference marks, the axis must
always be homed at a specific point of the machine which is referred to as Machine Reference
Point. The installer must place a home switch for each axis at the machine reference point.
When starting the search, the axis moves in the direction set by parameter REFDIREC and
at the feedrate indicated by parameter REFFEED1 until reaching the home switch. When
the axis presses the home switch, it starts moving in the opposite direction at the feedrate
set by parameter REFFEED2. It keeps on moving after releasing the home switch until the
CNC detects a marker pulse (I0) from the feedback device.
Home search with a feedback system that has distance-coded
reference marks.
When the feedback system has distance-coded reference marks (coded I0) may be
referenced (homed) at any point of the machine; there is no need for home switches.
However, it will be necessary to set the machine reference point if the axis uses leadscrew
error compensation because the amount of error at the machine reference point must be ·0·.
The axis moves the minimum distance possible, less than 200 mm, in the direction set by
parameter REFDIREC and at the feedrate indicated in "REFFEED2" until the CNC receives
a reference marker pulse from the feedback system.. If before receiving the reference signal,
the axis presses the home switch, it starts moving in the opposite direction and goes on with
the process getting away from the switch until the CNC receives the reference marker pulse
of the feedback system.
Redefine the machine reference point after having dismounted
or replaced the feedback system.
Sometimes, to readjust the machine, it is necessary to take down the feedback device, thus
when putting back up, the new home point might no coincide with the previous one.
Since the home point must still be the same, the difference between the new point and the
old point must be assigned to parameter REFSHIFT . This way, when the axis finds the I0,
it moves the distance indicated in REFSHIFT and at that point updates its coordinate to the
value of REFVALUE..
Parameter. Meaning.
I0TYPE Reference mark (I0) type
DECINPUT The axis has a home switch.
REFDIREC Home searching direction.
REFFEED1 Fast home searching feedrate.
REFFEED2 Slow home searching feedrate.
Parameter. Value.
I0TYPE Increasing distance-coded
Decreasing distance-coded
REFDIREC Home searching direction.
REFFEED2 Slow home searching feedrate.
Parameter. Value.
REFVALUE Home position.
REFSHIFT Offset of the reference point (home)