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8. WELDING
SETTING WELDING CURRENT AND VOLTAGE
When the wire had been installed and gas had been set it is possible to start
welding.
1. The appliance must be plugged into the mains, the ON/OFF switch on "I".
2. To select the voltage use voltage switch
2
.
3. To select the current (that is linked to the wire speed) use the potentiometer
5
.
Duty cycle mean percentage of time cycle of 10 minutes, after which the
machine can withstand weld at a given current, without switching off by means
of the thermal protection.
For orientating adjusting of the welding current and voltage you can use
empirical relation U
2
= 14+0,05 I
2
. From that you can specify desired voltage.
According to this relation, one can determine the required voltage. When
setting the voltage has to considered the decline in load welding. The voltage
drop is approximately 4.5-5.0 V at 100 A.
Setting the welding current is performed so that the selected welding voltage
settles the desired welding current by increasing or decreasing wire feed speed
until the optimum welding arc is reached .
Please note that the actual settings for optimum arc may vary slightly
depending on the position of the weld material and voltage fluctuations.
To achieve a good quality of the welds and the optimum setting of the welding
current is necessary that the distance of the welding tip from the material is
about 10 times the diameter of the welding wire (Fig. 6)
Fig. 6 – Distance of the welding tip from the material
