Resistance is changed by the variations in arc length. What does a SMAW power source provide to maintain the arc?

• A. Open circuit voltage
• B. Current
• C. Voltage
• D. Metal Droplets

Answer: (C)

When the arc length changes, the gap’s resistance changes, but the weld arc is kept alive by the welding power source delivering a voltage across that gap. That arc voltage drives current through the arc, and the current adjusts as needed to keep the arc burning despite the changing resistance. Open circuit voltage isn’t present during welding, and metal droplets are just a byproduct of the process. The key energy that keeps the arc going in this context is the voltage across the arc.