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ADVANCED OPERATION - Special functions: Advanced splicing parameters
Prefusion before alignment: EARLY PREFUSION
The parameter EARLY PREFUSION is specifically designed
for the problems associated with carbon coated fibers. The
carbon coating has a tendency to give off more material
during arc ignition, and thus cause more build-up on the
electrodes. To avoid this, you can set EARLY PREFUSION to
ON, and the prefusion will occurs before the fibers are
brought close to the electrodes during alignment.
Alignment accuracy: ALIGN ACCURACY
Alignment is executed with the degree of accuracy specified in this parameter. There may be
cases, however, where the splicing combination demands, or allows for, a greater, or lesser,
degree of accuracy than the default of 0.15
m
m. You should keep in mind, though that
increased accuracy is paid for in terms of the increased time it takes for the splicer to align
the fibers.
Arc-on alignment: AOA CURRENT
At arc ignition an electromagnetic field is estab-
lished that exerts force on the fibers, bending
them out of alignment (see adjacent picture).
After initial ignition, the force disappears, and
most fibers comes back into place. However,
carbon coated and small core fibers are pulled
to a significantly different degree than other
fiber types , so with these fibers, it is particularly
likely that the fibers will lose their alignment at
arc ignition. To compensate for this problem, the
FSU 995 FA is equipped with the option of set-
ting a low current that can be ignited during fine
alignment. This ensures that the alignment is
carbon coating
electrode
force at
igniting
very low current (6 mA)
Increased force because of the conductivity of
carbon coating
Splice loss calibration: LOSS SHIFT
Use the parameter LOSS SHIFT to calibrate the FSU995 when there is a consistent mismatch
between measured and estimated splice loss. Set the parameter to a value that reflects the
average difference between the measured loss, shown on the external measuring equipment,
and the estimated loss, calculated by the FSU 995.
Increased build-up on electrodes from
carbon coated fiber
done according to the position that the fibers
will be in during splicing. The default value of the AOA CURRENT parameter is 6.5 mA, and it
is important not to deviate too far from the default value. Too high of a current will lead to
matchsticking. Too low of a current can permanently damage the electrical equipment in
such a way that the arc won’t be able to ignite.
Automatic arc re-centering : AUTO ARC CENTER
Automatic Arc Re-centering
is an automatic function that prevents high splice losses caused
by uneven distribution of energy between left and right fibre during arc ignition. The reason
for the uneven energy distribution is that material from the fibres are deposited on the elec-
trodes when splicing, changing the electromagnetic field of the arc. This may, as a result,
cause high splice losses. To avoid this to happen, the splicing position is automatically ad-
justed, before every splice, with an offset to compensate for the predicted arc change. It is
this offset that is displayed in the parameter AUTOXCT OFFSET (p.62).