How does the voltage output behave once set on a typical MIG welder?

How does the voltage output behave once set on a typical MIG welder?

• A. It is turned off after welding
• B. It remains constant
• C. It fluctuates with temperature
• D. It increases over time

Answer: (B)

In a typical MIG welder, you set the arc voltage and the machine keeps that voltage constant during welding. It’s a constant-voltage power supply, so the arc length stays stable as you weld. The wire feed speed controls the current, not the voltage, so as you feed more wire the current rises while the voltage stays roughly the same. Temperature or time fluctuations don’t normally cause the voltage to drift under normal operation—the unit regulates the preset voltage to maintain a steady arc. The idea is that the voltage should remain constant, while changes in welding are handled by adjusting the wire feed and resulting current.

In a typical MIG welder, you set the arc voltage and the machine keeps that voltage constant during welding. It’s a constant-voltage power supply, so the arc length stays stable as you weld. The wire feed speed controls the current, not the voltage, so as you feed more wire the current rises while the voltage stays roughly the same. Temperature or time fluctuations don’t normally cause the voltage to drift under normal operation—the unit regulates the preset voltage to maintain a steady arc. The idea is that the voltage should remain constant, while changes in welding are handled by adjusting the wire feed and resulting current.