What type of power source is used with GMAW?

What type of power source is used with GMAW?

• A. Constant Voltage
• B. Constant Current
• C. Pulsed Voltage
• D. Variable Current

Answer: (A)

In GMAW, the power source is designed to hold the arc voltage nearly constant while the wire feed controls the amount of current flowing to the weld. Keeping the voltage steady helps maintain a stable arc length and consistent weld puddle as you vary the wire feed speed to control heat input. If the current were kept constant instead, changes in wire feed and arc length would cause larger fluctuations in arc characteristics, making the weld harder to control. Pulsed voltage can be used in some GMAW setups to modulate heat, but the standard, everyday power source for GMAW is a constant voltage supply. Variable current isn’t a defined, typical power-supply mode for this process.

In GMAW, the power source is designed to hold the arc voltage nearly constant while the wire feed controls the amount of current flowing to the weld. Keeping the voltage steady helps maintain a stable arc length and consistent weld puddle as you vary the wire feed speed to control heat input. If the current were kept constant instead, changes in wire feed and arc length would cause larger fluctuations in arc characteristics, making the weld harder to control. Pulsed voltage can be used in some GMAW setups to modulate heat, but the standard, everyday power source for GMAW is a constant voltage supply. Variable current isn’t a defined, typical power-supply mode for this process.