Fagor CNC 8055i, Installation Manual

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Installation manual
CNC 8055
CNC 8055i
CONC
EPTS
7.
S
OFT
: V02.2
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Reference systems
7.6.1 Machine reference (home) search
With this CNC, home search may be performed in jog mode or by program. Home search may be
carried out on one axis at a time or on several axes at the same time.
When this search (with or without distance-coded Io) is carried out in JOG mode, the active zero
offset will be cancelled and the CNC will display the position values indicated by axis parameter
REFVALUE (P36). In all other cases, the active part zero will be maintained and the CNC will display
the position values with respect to that part zero.
• On axes with no distance-coded feedback system:

The CNC moves all selected axes that have a home switch in the direction indicated by axis
parameters REFDIREC (P33).
This movement will be carried out at the feedrate established by axis parameters REFEED1
(P34) until the home switch is hit.
Once all the axes have reached their respective home switches, the machine reference
search (marker pulse) will be performed moving the selected axes one by one and in the
selected sequence.
This second movement will be carried out at the feedrate established by axis parameters
REFEED2 (P35) until the marker pulse of the feedback system is found.

If machine parameter I0TYPE (P52) =3, the home search procedure is the following:
The CNC moves all selected axes that have a home switch in the direction indicated by axis
parameters REFDIREC (P33).
This movement will be carried out at the feedrate established by axis parameters REFEED1
(P34) until the home switch is hit.
Once all the axes have reached their respective home switches, the axes move back one
at a time in the selected order and at REFEED2 until the switch is released.
Once released, it will recognized the first reference mark detected without changing the
moving direction or the feedrate.
• On axes with distance-coded feedback system:
Home switches are no longer necessary since the axes may be homed anywhere along its travel.
However, axis parameter REFVALUE (P36) must be set when operating with leadscrew error
compensation.
The home search will be performed on one axis at a time and in the selected sequence.
The axes will move a maximum of 20 mm or 100 mm in the direction set by axis parameter
REFDIREC (P33) at the feedrate set by axis parameter REFEED2 (P35).
If, during the home search, the home switch is pressed (if any), the CNC will reverse the homing
direction.
If after the machine is all set up it is necessary to remove the feedback system, it may happen that
when it is reinstalled, its marker pulse is no longer at the same physical location as it was before.
In that case, the distance (shift) between the previous marker pulse location and the current one must
be assigned to axis parameter REFSHIFT (P47) of the affected axis in order for the machine reference
point (home) to remain the same.
This way, when searching home, the axis will move this additional distance, indicated by axis parameter
REFSHIFT (P47) value, after finding the new marker pulse of the feedback system. This movement
is carried out at the feedrate indicated by axis parameter REFEED2 (P35).