5.4 CONNECTION TO THE MAIN POWER SUPPLY
- Before making any electrical connection, make sure the rating data of the welding machine correspond to the mains
voltage and frequency available at the place of installation.
- The welding machine should only be connected to a power supply system with the neutral conductor connected to
earth.
- the machine can be connected to a mains outlet fitted with fuses or an automatic circuit-breaker; the special earth
terminal should be connected to the earth conductor (yellow-green) of the power supply line.
WARNING! Failure to observe the above rules will make the (Class 1) safety system installed by the
manufacturer ineffective with consequent serious risks to persons (e.g. electric shock) and objects
(e.g. fire).
5.5 CONNECTION OF THE WELDING CABLES
WARNING! BEFORE MAKING THE FOLLOWING CONNECTIONS, MAKE SURE THE WELDING
MACHINE IS SWITCHED OFF AND DISCONNECTED FROM THE POWER SUPPLY OUTLET.
5.5.1 MMA WELDING
Almost all coated electrodes are connected to the positive pole (+) of the power source; as an exception to the
negative pole (-) for acid coated electrodes.
Turn the welding cable connectors right down into the quick connections (if present), to ensure a perfect electrical
contact; otherwise the connectors will overheat, resulting in the 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 jeopardize safety and result in poor welding.
6. WELDING
- It is most important to refer to the manufacturer
’s instructions indicated on the stick electrode packaging. This will
indicate the correct polarity of the stick electrode and the most suitable current.
- The electrode in use and the type of the joint to be carried out - see below the currents corresponding to various
electrode diameters:
Diameter
ø 1.6
ø 2.5
ø 3.2
ø 4.0
ø 5.0
Welding current
30-80A
60-100A
80-140A
140-170A
170-250A
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).
6.1.1 Procedures
- 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.
All the time keep this distance as even as possible. Remember that the angle of the electrode as it advances, should
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