A constant current welding machine produces which type of volt-amp curve?

A constant current welding machine produces which type of volt-amp curve?

• A. Drooping
• B. Variable
• C. Rising
• D. Flat

Answer: (A)

Constant current welders regulate the current and let the arc voltage vary with arc length and conditions. As the current setting is held or increased, the arc voltage tends to fall because the arc becomes easier to sustain at higher current. This causes the volt-amp curve to slope downward, which is described as a drooping curve. A flat curve would mean voltage stays constant with changing current (more like a constant-voltage machine), while a rising curve would imply voltage increases with current—patterns that don’t match how CC welding behaves. A generic or variable label doesn’t capture this characteristic shape.

Constant current welders regulate the current and let the arc voltage vary with arc length and conditions. As the current setting is held or increased, the arc voltage tends to fall because the arc becomes easier to sustain at higher current. This causes the volt-amp curve to slope downward, which is described as a drooping curve. A flat curve would mean voltage stays constant with changing current (more like a constant-voltage machine), while a rising curve would imply voltage increases with current—patterns that don’t match how CC welding behaves. A generic or variable label doesn’t capture this characteristic shape.