26 mm 2 (10 AWG) ground wire must be used, and in all other markets a 6 mm 2 must be used. Understanding how to ground metal electrical box components is not just about following code—it's about protecting your home and family. This guide provides clear, step-by-step instructions for beginners. Proper grounding is an essential aspect of electrical safety that ensures your home's. Today, we're diving deep into the world of distribution box grounding, breaking down the standards, and shining a light on those sneaky mistakes that even experienced electricians sometimes make. These locations are usually marked with grounding symbols for easy cable crimping.