Fagor CNC 8055i, Installation Manual

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Installation manual
CNC 8055
CNC 8055i
CONC
EPTS
7.
S
OFT
: V02.2
X
·335·
Reference systems
Gantry axes
Home search on Gantry axes may be carried out in JOG mode or by program. It will be carried out
as follows:
• On axes with no distance-coded feedback system:

The CNC starts the movements of both axes in the direction indicated by axis parameter
REFDIREC (P33) of the main axis.
These movements will be performed at the feedrate indicated by axis parameter REFEED1
(P34) for the main axis until the home switch for this axis is hit.
Then, the home search will start on both axes at the feedrate indicated by axis parameter
REFEED2 (P35) of the main axis.
The CNC will wait until the marker pulse (home) of the slave axis is found and then, it will
look for the marker pulse from the main axis.

If machine parameter I0TYPE=3, the home search procedure is the following:
The CNC starts the movements of both axes in the direction indicated by axis parameter
REFDIREC (P33) of the main axis.
These movements will be performed at the feedrate indicated by axis parameter REFEED1
(P34) for the main axis until the home switch for this axis is hit.
It then moves back at REFEED2 until the home switch is released.
Once the switch has been released, the CNC will wait until the marker pulse (home) of the
slaved axis is found and then, it will look for the marker pulse from the main axis. This is done
without changing the direction or the speed of the movement.
• On axes with distance-coded feedback system:
The CNC starts moving both axes in the direction indicated by axis parameter REFDIREC (P33)
for the main axis at the feedrate indicated by axis parameter REFEED2 (P35) of the main axis.
The CNC will wait until the marker pulse (home) of the slave axis is found and then, it will look
for the marker pulse from the main axis.
If the difference obtained between both reference positions is not the same as the one indicated
by axis parameters REFVALUE (P36) for both axes, the CNC will correct the position of the slave
axis. This will end the home search operation.
When this search is carried out in the JOG mode, the active zero offset will be cancelled and the
CNC will display the position value indicated by axis parameter REFVALUE (P36) for the main axis.
In all other cases, the displayed position value will be referred to the zero offset (or part zero) active
before the home search.
If the axis parameter REFDIREC (P33) of the main axis has been set for a positive direction, the axis
parameter REFVALUE (P36) of the slave axis must be set to a value lower than that assigned to the
main axis.
Likewise, if the axis parameter REFDIREC (P33) of the main axis has been set for a negative direction,
the axis parameter REFVALUE (P36) of the slaved axis must be set to a value greater than that
assigned to the main axis. They must never have the same value.
When encoders are used for feedback, the difference between the values assigned to axis parameters
REFVALUE (P36) of both axes must be smaller than the pitch of the ballscrew.
It is recommended that the distance between the marker pulses of both encoders be half the leadscrew
pitch.