26 mm 2 (10 AWG) ground wire must be used, and in all other markets a 6 mm 2 must be used. Power from factory ground must be installed by a qualified electrician. Grounding of the units: Attach a ground wire from one of. Whether you're a seasoned pro or just starting out, this comprehensive guide will give you practical insights into proper grounding techniques, with a special focus on how selecting quality materials from a reliable building material supplier impacts your entire system's safety and longevity. This helps to reduce the potential difference that exists between conductive parts and the earth. The basic rule achieves this through an equipment grounding jumper; four exceptions. The correct connection method of Distribution box grounding wire mainly includes the following steps: 1. IN ELECTRICAL STATIONS INCLUDING TRANSMISSION AND DISTRIBUTION SUBSTAT GR THAN 8 FT FROM THE FENCE. THE FENCE SHALL BE GROUNDED SEPARATELY FROM THE GRID UNLESS OTHERWISE NOTED ON THE A PROPRIATE PROJECT DRAWING.