The statement 'FCAW and GMAW use CV power sources because they are ideal for semi-automatic processes' is:

• A. True
• B. False
• C. Not specified
• D. Depends on material

Answer: (A)

GMAW and FCAW rely on a continuous, automatically fed wire electrode, so having a constant-voltage power source keeps the arc stable as the wire feed speed changes. With a CV source, the arc voltage stays nearly fixed, while the welding current adjusts with the wire feed rate and arc length, giving consistent heat input, penetration, and bead shape across the joint. If the supply were constant-current, small changes in arc length or wire feed could cause large current swings, making the arc unstable and the weld quality unpredictable—especially in semi-automatic setups where the operator doesn’t manually dial in current for every inch of weld. That stability and control is why CV power sources are preferred for these processes, making the statement true.