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ELECTRODE WELDING AND GOUGING Constant Current characteristic (ACA)

U

A flatter constant current characteristic is optimal for Manual Metal Arc Welding (stick), providing a higher current (within limits) when the arc length shortens. U = 20 + 0,04 * I (IEC 974)

I

Constant Voltage characteristic (CV)

U

I

For Wire Welding the ideal characteristic is constant voltage. It will reduce the current if arc gets too long, thereby reducing the meltoff and allowing the welding wire to be fed closer to the melt pool again. If the arc gets too short the current will increase, the melt-off will increase, and normal arc length will automatically be established again.

4.01

U = 14 + 0,05 * I (IEC 974)

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