Fagor CNC 8060, Installation Manual, Page: 156 / 698

Installation manual.
CNC 8060
CNC 8065
2.
MACHINE PA
RAMETERS.
Machin
e
parame
ters
for the
axe
s
an
d
spind
les.
·156·
(R
EF
: 1709)
the SANALOG from the PLC, its value will also be given in ten-thousandths of a millimeter
or thousandths of a degree. The drive smoothes the command using a cubic interpolation
and closes the position loop every 256 microseconds.
• The feedback from the drive to the CNC arrives as absolute coordinate, in ten-
thousandths of a millimeter or thousandths of a degree (same as in velocity-Sercos
mode).
• The drive controls the home search. Before starting the home search, the spindle stops
if it is turning.
• The drive calculates the following error (lag).
• The drive applies feed-forward and AC-forward.
FBACKSRC
Feedback type.
Parameter valid for linear and rotary axes and spindles.
Parameter valid for a Sercos drive.
Possible values: Internal / External / IExternal.
Default value: Internal.
Associated variable: (V.)[ch].MPA.FBACKSRC.xn
Parameter included in the SERCOSDATA table.
Type of feedback used to close the position loop. Refer to the drive manual for further detail.
When using internal feedback, the position value is taken from motor feedback whereas
when using external feedback, it is taken from direct feedback. When using iexternal
feedback, the feedback may be swapped via PLC using the FBACKSEL(axis) mark. When
using external or iexternal feedback, we recommend setting parameter
FBACKDIFF.
When the type of feedback is external or iexternal, the CNC can enable the
combined feedback; parameter FBMIXTIME.
When the type of feedback is iexternal, the CNC uses the internal feedback (motor
feedback) on power-up, when resetting the drive and when initializing the Sercos ring.
Tandem axes do not admit the iextenrnal type of feedback. In a tandem axis, both
axes must have the same type of feedback, external or internal, but usually, the master axis
uses external feedback and the slave axis the internal one.
FBACKDIFF
Maximum difference between feedbacks.
Parameter valid for linear and rotary axes.
Parameter valid for a position-Sercos drive.
Possible values: Within ±99999.9999 mm or degrees / within ±3937.00787 inch.
Default value: 0 (no monitoring).
Associated variable: (V.)[ch].MPA.FBACKDIFF.xn
Parameter included in the SERCOSDATA table.
The CNC takes this parameter into account only on axes with external or einternal
feedback.
When the system has dual feedback, this parameter may be used to monitor the difference
between both feedbacks. If the difference exceeds the set value, the CNC will display the
corresponding error message. When defined with a "0" value, there will be no monitoring.
FBACKSRC FBMIXTIME Type of feedback.
Internal (Not being used) Internal feedback.
External 0 External feedback.
External Value greater than ·0·. The combined (mixed) feedback is active.
IExternal 0 The feedback type may be swapped from the PLC
using the mark FBACKSEL(axis). Internal or
external feedback.
IExternal Value greater than ·0·. The feedback type may be swapped from the PLC
using the mark FBACKSEL(axis). Internal feedback
or combined (mixed) feedback.