Masterweld MW2040, Instructions For Use And Maintenance Manual, Page: 10 / 29

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The power source capacity must be at least
6.5 kVA so that the apparatus can work in the maxi-
mum current range. If this principle is neglected,
there is a danger that the apparatus will not work
properly or at all while welding on the maximum
welding current or, as the case may be, damage to
the apparatus may result because of extensive drops
and increases in the supply voltage.
Controlling and indicating elements
Picture 8
Position 1 Wire feed rate controller (output regu-
lator).
Position 2 Voltage correction regulator (arc
length regulator).
Position 3 Apparatus ‘ON’ indicator.
Position 4 Apparatus overheating indicator.
The welding output is adjusted by the controller
1 (Pic. 8) according to the welded material thick-
ness. The controller 2 is used for the voltage correc-
tion (and it regulates the arc length at the same
time).
The control lamps inform about the turning the
machine on (3) and thermal protection activation (4).
Green light is on after switching on the apparatus.
If the apparatus is overheated or its supply voltage is
too low or too high, the welding process will be
automatically stopped and yellow light will be on.
Once the yellow control lamp is off, the apparatus is
prepared for the service again.
ADJUSTMENT OF THE WELDING OUTPUT
The welding output regulator adjusts, at the same
time, the output voltage and wire feed rate. At the
same time, both these parameters determine, for
which material thickness is the relevant setting suit-
able.
Table 2 shows reference values of welding parame-
ter settings for various thicknesses of materials.
The Table is prepared for the basic settings in weld-
ing with the 0.8 mm dia wire. If the 0.6 dia wire is
used, then it will be necessary to set the welding
output slightly lower, while for 1.0 mm dia wire
slightly higher.
Setting of parameters according to the material
thickness (of a reference value only)
Material thickness
Feed rate potentiome-
ter position
0.5 1
0.75 3
1 4
1.5 6
2 7
3 8
4 10
Table 2
VOLTAGE CORRECTION SETTINGS
The voltage correction function influences the set-
ting of the arc length and its temperature. If the
correction is shifted to the negative values, the arc
gets shorter and cooler, while the correction shifts to
positive values, longer and hotter.
Along with various combinations of wire diameters
and usage of various protective gas types, this volt-
age correction influences the arc properties. If the
arc is too convex, then it is short and cool. In such
case the correction to the positive values will be
necessary. If you need a shorter arc, e.g. to avoid
material penetrations in welding, a correction to the
negative values will be necessary.
IMPORTANT NOTE: If you start welding for the first
time, it will be suitable to set the voltage correction
regulator into the middle position!
WARNING!
Any welding operations in places with
explosion/fire hazard are strictly forbidden!
Welding gaseous products might be harmful to hu-
man health! Provide for good ventilation during
welding operations!
Welding by the MIG/MAG method
a) Connect the gas hose from the gas cylinder
pressure-reducing valve to the B3 outlet (Pic. 2)
on the rear panel. Open the gas valve on the gas
cylinder.
b) Connect the apparatus to the mains.
c) Switch the B1 main switch on (Pic. 2).
d) Put the wire reel in its place; see “How to install
the wire reel”.
e) Lead-in the wire to the wire feed mechanism.
See “Leading-in the wire”.
Principle of MIG/MAG welding
Welding wire is leading from the roller into the flow
drawing tie with the use of the feed. The Arc joins
thawing wire electrode with welding material. Weld-
1 3 4 2