Which welding processes are noted as using constant voltage power sources due to semi-automatic operation?

• A. FCAW and GMAW
• B. GMAW and SMAW
• C. FCAW and SMAW
• D. GMAW and SAW

Answer: (A)

Constant voltage power sources work well when the welding process uses an automatic wire feeder. In MIG welding (GMAW) and flux-cored arc welding (FCAW), the electrode is fed automatically, and the operator controls travel speed and stick-out. A constant voltage source keeps the arc voltage steady, while the current naturally adjusts as the wire feed rate and arc length change. This creates a stable arc and consistent bead without needing to constantly tweak the current, which suits semi-automatic operation perfectly. In contrast, manually controlled processes like SMAW (stick) and many SAW setups rely more on controlling current directly, so they aren’t typically described as using constant voltage power sources.