What is open circuit voltage?

What is open circuit voltage?

• A. The voltage in the welding circuit while the arc is flowing
• B. The voltage before power is turned on or when an arc is struck
• C. The voltage across the workpiece after cooling
• D. The voltage of the protective ground during operation

Answer: (B)

Open circuit voltage is the voltage across the welding power source’s output when no current is flowing. In other words, it’s the no-load voltage you’d measure with the circuit open, before the arc is struck. This is typically higher than the voltage during welding, because with no current the source isn’t dropped across internal resistances. When you do strike the arc and current starts to flow, the voltage falls to the welding voltage and stays relatively lower as long as the arc continues. So the description that matches this concept is the one referring to the voltage present before the arc is struck (no-load condition).

Open circuit voltage is the voltage across the welding power source’s output when no current is flowing. In other words, it’s the no-load voltage you’d measure with the circuit open, before the arc is struck. This is typically higher than the voltage during welding, because with no current the source isn’t dropped across internal resistances. When you do strike the arc and current starts to flow, the voltage falls to the welding voltage and stays relatively lower as long as the arc continues. So the description that matches this concept is the one referring to the voltage present before the arc is struck (no-load condition).