- If the distance is right the pilot arc will immediately transfer to the piece,
an authorised service centre, which will be able to carry out the special
causing the cutting arc to strike.
tests needed after the repair has been done.
- Move the torch at a constant rate over the surface of the piece along
the ideal cutting line.
Compressed air filter
- Adjust the cutting rate according to the thickness and the selected
- The filter is designed for automatic condensation drainage whenever it
current, making sure that the arc comes out of the lower surface of the
is disconnected from the compressed air line.
piece at an inclination of 5-10° to the vertical in the opposite direction
- Inspect the filter regularly; if there is water in the glass it can be drained
to the cutting direction.
off manually by pushing the drain connector upwards.
- If the torch and piece are too far apart or if there is no material (end of
- If the filter cartridge is especially dirty it must be changed in order to
cut) the arc will immediately be cut off.
prevent an excessive pressure loss.
- It is always possible to break the (cutting or pilot) arc by releasing the
torch button.
EXTRAORDINARY MAINTENANCE
EXTRAORDINARY MAINTENANCE MUST BE CARRIED OUT ONLY
Drilling (FIG. M)
AND EXCLUSIVELY BY AUTHORISED EXPERT OR SKILLED
When this operation is necessary, or to start cutting in the centre of the
ELECTRICAL-MECHANICAL TECHNICIANS.
piece, strike the arc with an inclined torch and bring it gradually to a
________________________________________________________
vertical position.
- This procedure will stop arc returns or melted particles from damaging
WARNING! BEFORE REMOVING THE MACHINE PANELS AND
the nozzle hole and causing rapid wear.
WORKING INSIDE IT MAKE SURE THAT IT HAS BEEN SWITCHED
- It is possible to drill pieces directly when their thickness is below 25%
OFF AND DISCONNECTED FROM THE MAIN POWER SUPPLY.
of the maximum allowed range.
If checks are carried out inside the machine while it is live, this may
cause serious electric shock due to direct contact with live parts.
7. MAINTENANCE
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________________________________________________________
- Inspect the inside of the machine regularly, with a frequency depending
on the amount of use and dust in the environment, and remove dust
WARNING! BEFORE CARRYING OUT MAINTENANCE
that has deposited on the transformer, rectifier, inductance and
OPERATIONS, MAKE SURE THAT THE PLASMA CUTTING SYSTEM
resistors, using a jet of dry compressed air (max 10 bar).
IS SWITCHED OFF AND DISCONNECTED FROM THE MAIN POWER
- Do not direct the jet of compressed air onto the electronic boards; these
SUPPLY.
can be cleaned with a very soft brush or suitable solvents.
________________________________________________________
- Take the opportunity to make sure the electrical connections are tight
and there is no damage to the wiring insulation.
ROUTINE MAINTENANCE
- Make sure the compressed air circuit hoses and connections are intact
ROUTINE MAINTENANCE CAN BE CARRIED OUT BY THE
and leak-free.
OPERATOR.
- When these operations have been completed, re-assemble the panels
on the machine and tighten the fastening screws right down.
TORCH (FIG. N)
- Never ever carry out cutting operations with the machine open.
Depending on the amount of use, make regular checks on the wear of the
parts of the torch concerned with the plasma arc and proceed likewise if
8. TROUBLESHOOTING
cutting defects are noted.
IN THE CASE OF UNSATISFACTORY OPERATION, AND BEFORE
1- Spacer.
CARRYING OUT MORE SYSTEMATIC TESTS OR CONTACTING
Change it if it is so deformed or covered with slag that it is impossible to
YOUR SERVICING CENTRE CARRY OUT THE FOLLOWING
maintain the correct position of the torch (distance and
CHECKS:
perpendicularity).
- Check whether the yellow LED is ON, indicating triggering of the
thermal cutout, over- or under-voltage or shorting.
2- Nozzle holder.
- Make sure that the nominal duty cycle has been respected; if the
Unscrew it manually from the head of the torch. Clean it carefully or
thermal cutout triggers, wait until the machine cools down naturally
change it if it is damaged (burnt, deformed or cracked). Make sure the
then make sure the fan is working properly.
top metal section is intact (torch safety rocker).
- Check the power supply voltage: if it is too high or too low the machine
3- Nozzle.
will not work.
Check for wear on the plasma arch passage hole and on the inside and
- Make sure there is no shorting at machine output: if there is shorting
outside surfaces. If the hole is larger than the original diameter or if it is
remove the cause.
deformed, change the nozzle. If the surfaces are particularly oxidized
- Make sure the cutting circuit connections are correct, in particular that
clean them with very fine abrasive paper.
the earth cable clamp is actually connected to the piece with no
4- Air distribution ring.
insulating material in between (e.g. paint).
Make sure there are no burns or cracks and that the air passage holes
are not blocked. If damaged, change the ring immediately.
MOST COMMONLY OCCURRING CUTTING DEFECTS
5- Electrode.
During cutting operations it is possible that defects occur, which are not
Change the electrode when the depth of the crater formed on the
normally caused by operating faults in the system but by other
emitter surface is approx. 1.5 mm (FIG. O).
operational matters such as:
6- Torch body, handgrip and cable.
a-Insufficient penetration or excessive slag formation:
These components do not normally need any particular maintenance
- Cutting rate too high.
apart from regular inspection and careful cleaning without using any
- Over-inclined torch.
kind of solvent. If the insulation is damaged, with breakages, cracks or
- Piece too thick or cutting current too low.
burns etc., or if the electric leads are loose, the torch may not be used
- In appropriate compressed air pressure-flow.
because it does not satisfy safety requirements.
- Worn electrode and torch nozzle.
In this case repairs (extraordinary maintenance) cannot be done on
- Inappropriate nozzle-holder tip.
the spot and the torch must be sent to an authorised service centre,
which will be able to carry out the special tests needed after the repair
b- Arc transfer failure:
has been done.
- Worn electrode.
In order to keep the torch and cable in good working order, take the
- Poor contact of the return cable terminal clamp.
following precautions:
c-Interrupted cutting arc:
- do not allow the torch and cable to come into contact with hot or red-
- Cutting rate too low.
hot parts.
- Torch-piece distance too high.
- do not pull the cable hard.
- Worn electrode.
- do not pass the cable over pointed or sharp edges or over abrasive
- A safeguard has triggered.
surfaces.
d- Inclined cut (not perpendicular):
- wind the cable into regular loops if it is longer than needed.
- Incorrect torch position.
- do not pass over the cable with any vehicle and do not stand on it.
- Asymmetric wear on nozzle hole and/or incorrect assembly of torch
Warning.
components.
- Before carrying out any work on the torch leave it to cool for at least the
- Inappropriate air pressure.
complete “post air" time
e-Excessive nozzle and electrode wear:
- Except in special cases, we recommend changing the electrode and
- Air pressure too low.
nozzle at the same time.
- Contaminated air (moisture-oil).
- Assemble the torch components in the correct order (the reverse of the
- Damaged nozzle holder.
order for dismantling).
- Too many pilot arc strikes in air.
- Make sure that the distributor ring is fitted the right way round.
- Excessive cutting rate with melted particles returning onto torch
- When re-assembling the nozzle holder, screw it down manually, forcing
components.
it slightly.
- Never ever fit the nozzle holder before you assemble the electrode,
distributor ring and nozzle.
- Do not keep the pilot arc struck in air for no reason as this will increase
electrode, diffuser and nozzle wear.
- Do not tighten the electrode too much as this could damage the torch.
- Prompt, correct inspection procedures for the consumable parts of the
torch are essential for safe, correct operation of the cutting system.
- If the insulation is damaged, with breakages, cracks or burns etc., or if
the electric leads are loose, the torch may not be used because it does
not satisfy safety requirements. In this case repairs (extraordinary
maintenance) cannot be done on the spot and the torch must be sent to
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