Telwin Marte 150 Bedienungsanleitung Seite 7

couplings (if present), so as to ensure perfect electrical contact;
otherwise, the connectors will overheat, wear rapidly and become
inefficient.
- Use welding cables that are as short as possible.
- Do not use metal structures that are not part of the workpiece to
substitute the welding current return cable; this could endanger
safety and produce an unsatisfactory weld.
6. WELDING: DESCRIPTION OF THE PROCEDURE
These welding machines consist of a drooping specification, single
phase transformer and are suitable for welding with alternating
current using coated electrodes (E 43 R type) based on the diameters
given on the data plate.
To switch on the welding machine operate the main switch (Fig. B-1).
The intensity of the supplied welding current can be adjusted
continuously, by means of a manually operated magnetic shunt (Fig.
B-2).
The value of the current setting, (I
graduated scale (Fig. B-3) on the top or side panel of machines
where it is provided.
THERMOSTATIC PROTECTION
This welder is automatically protected from thermic overheating
(thermostat automatic re-start).
performance temperature, the protections cut off the supply circuit,
igniting the yellow lamp on the front panel (Fig. B-4). After a few
minutes' cooling the protection will reopen the supply line and turn off
the yellow lamp. The welder is ready for further use.
WELDING
- Use electrodes suitable for working in alternating 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)
1.6
2
2.5
3.2
- 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.
- In addition to being determined by the selected current intensity,
the mechanical characteristics of the welded join are 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 dry and protected by suitable packaging or
containers).
Welding 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. D).
- 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
7. MAINTENANCE
WARNING! BEFORE CARRYING OUT MAINTENANCE
OPERATIONS MAKE SURE THE WELDING MACHINE IS
SWITCHED OFF AND DISCONNECTED FROM THE MAIN
POWER SUPPLY.
) can be read in Amps on the
2
When the windings
Welding current (A)
min.
25 50
40 80
60 110
80 160
Fig. E
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, using a jet of dry compressed air
(max. 10 bar).
- 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.
reach - Never, ever carry out welding operations while the welding machine
is open.
- If necessary use a very thin layer of grease, at a high temperature,
to lubricate the moving parts of the regulators (threaded shaft,
sliding surfaces, shunts etc.).
- Replacing the power supply cable: before replacing the cable,
identify the screw-connecting terminals L1 and L2 (N) on the
switches (Fig. F).
- 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
max.
separate from the low voltage ones of the secondary transformer.
Use all the original washers and screws when closing the casing.
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