Maintenance; Routine Maintenance; Torch; Extraordinary Maintenance - TIG 250 (DC) Manuel D'instructions

WARNING: do not hit the electrode on the workpiece, this could damage the
electrode and make strike-up difficult.
- As soon as arc is ignited, try to maintain a distance from the workpiece equal to the
diameter of the electrode in use. Keep this distance as much constant as possible
for the duration of the weld. Remember that the angle of the electrode as it advances
should be of 20-30 grades.
- At the end of the weld bead, bring the end of the electrode backward, in order to
fill the weld crater, quickly lift the electrode from the weld pool to extinguish the arc
(CHARACTERISTICS OF THE WELD BEAD - FIG. N).

7. MAINTENANCE

WARNING! BEFORE CARRYING OUT MAINTENANCE OPERATIONS
MAKE SURE THE WELDING MACHINE IS SWITCHED OFF AND DISCONNECTED
FROM THE MAIN POWER SUPPLY.

7.1 ROUTINE MAINTENANCE

ROUTINE MAINTENANCE OPERATIONS CAN BE CARRIED OUT BY THE
OPERATOR.

7.1.1 Torch

- Do not put the torch or its cable on hot pieces; this would cause the insulating
materials to melt, making the torch unusable after a very short time.
- Make regular checks on the gas pipe and connector seals.
- Accurately match collet and collet body with the selected electrode diameter in order
to avoid overheating, bad gas diffusion and poor performance.
- At least once a day check the terminal parts of the torch for wear and make sure they
are assembled correctly: nozzle, electrode, electrode-holder clamp, gas diffuser.

7.2 EXTRAORDINARY MAINTENANCE

EXTRAORDINARY MAINTENANCE MUST ONLY BE CARRIED OUT BY
TECHNICIANS WHO ARE EXPERT OR QUALIFIED IN THE ELECTRIC-
MECHANICAL FIELD, AND IN FULL RESPECT OF THE IEC/EN 60974-4
TECHNICAL DIRECTIVE.
WARNING! BEFORE REMOVING THE WELDING MACHINE PANELS
AND WORKING INSIDE THE MACHINE MAKE SURE THE WELDING MACHINE
IS SWITCHED OFF AND DISCONNECTED FROM THE MAIN POWER SUPPLY
OUTLET.
If checks are made inside the welding machine while it is live, this may cause
serious electric shock due to direct contact with live parts and/or injury due to
direct contact with moving parts.
- Periodically, and in any case with a frequency in keeping with the utilisation and with
the environment's dust conditions, inspect the inside of the welding machine and
remove the dust deposited on the electronic boards with a very soft brush or with
appropriate solvents.
- At the same time make sure the electrical connections are tight and check the wiring
for damage to the insulation.
- At the end of these operations re-assemble the panels of the welding machine and
screw the fastening screws right down.
- Never, ever carry out welding operations while the welding machine is open.
- After having carried out maintenance or repairs, restore the connections and wiring
as they were before, making sure they do not come into contact with moving parts or
parts that can reach high temperatures. Tie all the wires as they were before, being
careful to keep the high voltage connections of the primary transformer separate
from the low voltage ones of the secondary transformer.
Use all the original washers and screws when closing the casing.

8. TROUBLESHOOTING

IN CASE OF UNSATISFACTORY FUNCTIONING, BEFORE SERVICING MACHINE
OR REQUESTING ASSISTANCE, CARRY OUT THE FOLLOWING CHECK:
- Check that the welding current is correct for the diamter and electrode type in use.
- Check that when general switch is ON the relative lamp is ON. If this is not the case
then the problem is located on the mains (cables, plugs, outlets, fuses, etc.).
- Check that the yellow led (ie. thermal protection interruption- either over or
undervoltage or short circuit) is not lit.
- Check that the nominal intermittance ratio is correct. In case there is a thermal
protection interruption, wait for the machine to cool down, check that the fan is
working properly.
- Check the mains voltage: if the value is too high or too low the welding machine will
be stopped.
- Check that there is no short-circuit at the output of the machine: if this is the case
eliminate the incovenience.
- Check that all connections of the welding circuit are correct, particularly that the
work clamp is well attached to the workpiece, with no interferring material or
surface-coverings (ie. Paint).
- Protective gas must be of appropriate type (Argon 99.5%) and quantity.
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