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ELECTRODE WELDING AND GOUGING Secondary cables (welding and return cables) The cross-section dimension of a welding cable must be compatible with both the welding current which will be used and the total length of welding and return cable which will be used in the welding circuit. The first requirement is the maximum load the cable can carry without overheating. The following maximum load ratings apply to neoprene insulated welding cable at 25°C ambient temperature.

Cable CrossSection

Maximum welding current at varying duty cycles 100% 60% 30%

35 mm2

225A

290A

410A

0,42

2

50 mm

285A

365A

520A

0,56

70 mm2

335A

460A

650A

0,78

95 mm

430A

560A

790A

1,03

2

Weight kg per m.

As guideline, it should be noted that normal hand welding using coated stick electrodes and TIG welding is carried out at a duty cycle (effective welding time) of 30-40%, while wire welding and air carbon arc gouging may have a duty cycle of up to 60%.

The maximum current values are based on the capacity of the cables alone. However, the voltage drop in the cables will often be the decisive factor when choosing the right cable size. The theoretical voltage drop in 100 meters copper cable of four different cross sections is shown for increasing currents in the following diagram:

4.01

360