Which statement describes the volt-amp curve for constant voltage machines?

Which statement describes the volt-amp curve for constant voltage machines?

• A. Drooping volt-amp curve.
• B. Flat volt-amp curve.
• C. Rising volt-amp curve.
• D. Variable volt-amp curve.

Answer: (B)

Constant voltage machines regulate the arc voltage to stay essentially the same as you change the welding current. So, as current varies, the voltage remains fixed, which makes the volt-amp relationship appear flat. In other words, the arc voltage doesn’t sag or climb with increasing current, it stays about constant, giving a straight, horizontal look on the curve. If the curve drooped, it would mean voltage falls off as current rises; if it rose, voltage would increase with current; and a variable shape would indicate inconsistent regulation. The flat volt-amp curve best describes how a CV power source behaves.

Constant voltage machines regulate the arc voltage to stay essentially the same as you change the welding current. So, as current varies, the voltage remains fixed, which makes the volt-amp relationship appear flat. In other words, the arc voltage doesn’t sag or climb with increasing current, it stays about constant, giving a straight, horizontal look on the curve. If the curve drooped, it would mean voltage falls off as current rises; if it rose, voltage would increase with current; and a variable shape would indicate inconsistent regulation. The flat volt-amp curve best describes how a CV power source behaves.