Should background amperage be set lower than peak amperage in GTAW-P?

• A. Yes
• B. It should be higher
• C. It should be equal
• D. No

Answer: (A)

In GTAW-P the arc current is pulsed, cycling between a high peak and a lower background value. The background amperage should be set lower than the peak. This arrangement delivers heat in short bursts to melt the weld area, then allows the pool to cool during the background phase. Keeping the base current well below the peak lets you control heat input, reduce distortion, and manage the weld pool more precisely—especially on thin sections or when you want to avoid burning through. If the background current were equal to or higher than the peak, you’d lose the pulsing effect and end up with higher, more continuous heat input, making the weld harder to control and increasing the risk of burn-through or excess distortion.