- 8 -
On the end take a special terminal that is used to close the uncovered
part of the electrode.
This cable is connected to the terminal with the symbol (+)
Connecting the welding current return cable
This is connected to the piece being welded or to the metal bench
supporting it, as close as possible to the join being made.
This cable is connected to the terminal with the symbol (-)
Warnings:
- Turn the welding cable connectors right down into the quick
connections (if present), to ensure a perfect electrical contact;
otherwise the connectors themselves will overheat, resulting in
their rapid deterioration and loss of efficiency.
- The welding cables should be as short as possible.
- Do not use metal structures which are not part of the workpiece
to substitute the return cable of the welding current: this could
jeopardise safety and result in poor welding.
6. WELDING: DESCRIPTION OF THE PROCEDURE
- It is most important that the user refers to the maker’s instructions
indicated on the stick electrode packaging. This will indicate the
correct polarity of the stick electrode and the most suitable current.
- The welding current must be regulated according to the diameter of
the electrode in use and the type of the joint to be carried out: see
below the currents corresponding to various electrode diameters:
Ø Electrode (mm)
Welding current (A)
min.
max.
1.6
25
50
2
40
80
2.5
60
110
3.2
80
160
4
120
200
5
180
260
- The user must consider that, according to the electrode diameter,
higher current values must be used for flat welding, whereas for
vertical or overhead welds lower current values are necessary.
- As well as being determined by the chosen current intensity, the
mechanical characteristics of the welded join are also determined
by the other welding parameters i.e. arc length, working rate and
position, electrode diameter and quality (to store the electrodes
correctly, keep them in a dry place protected by their packaging or
containers).
Procedure
- Holding the mask IN FRONT OF THE FACE, strike the electrode
tip on the workpiece as if you were striking a match. This is the
correct strike-up method.
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
(Fig. G)
.
- 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. H
7. MAINTENANCE
WARNING! BEFORE CARRYING OUT MAINTENANCE
OPERATIONS MAKE SURE THE WELDING MACHINE IS
SWITCHED OFF AND DISCONNECTED FROM THE MAIN
POWER SUPPLY.
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.
- Inspect the welding machine regularly, with a frequency depending
on use and the dustiness of the environment, and remove the dust
deposited on the transformer, reactance and rectifier using a jet of
dry compressed air (max. 10bar).
- Do not direct the jet of compressed air on the electronic boards;
these can be cleaned with a very soft brush or suitable 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, which is regulated by the
potentiometer with a graduated amp scale, 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.