Red Seal Welding Practice Exam

The polarity used for PAC is DCEN. PAC stands for Plasma Arc Cutting, which is a thermal cutting process that involves an electric arc and a high-velocity jet of ionized gas. It is used to cut through electrically conductive materials. Options A and D are incorrect because they mention AC, which stands for Alternating Current. Since PAC requires a continuous flow of electricity to maintain the plasma arc, AC polarity is not suitable as it constantly switches direction. Option B is incorrect because DCEP stands for Direct Current Electrode Positive, which is the reverse polarity needed for welding applications. On the other hand, PAC requires DCEN (Direct Current Electrode Negative) polarity where the negative electrode is connected to the power supply and the positive electrode is connected to the workpiece. This creates a concentrated heat source that allows for better control and precision in cutting.