Final answer:
In GMAW, the number after the hyphen in the electrode classification generally refers to the wire diameter, which is directly related to the wire's current-carrying capacity.
Step-by-step explanation:
In Gas Metal Arc Welding (GMAW) electrode classification, the number after the hyphen usually refers to the wire diameter rather than voltage, amperage, or polarity. The diameter of welding wire is critical because it influences the current-carrying capacity; a larger diameter wire can carry more current. American Wire Gauge (AWG) is a standardized wire gauge system used in the United States, where a larger gauge number indicates a thinner wire. For instance, 10-gauge wire has a diameter of 2.588 mm. Understanding these aspects is crucial for selecting the appropriate welding parameters and achieving proper welding performance.