26 mm 2 (10 AWG) ground wire must be used, and in all other markets a 6 mm 2 must be used. Next, we describe directional elements suitable to provide ground fault protection in solidly- and low-impedance grounded distribution systems. We then analyze the behavior of ungrounded systems under ground fault conditions and introduce a new ground directional element for these systems. The voltage, system arrangement, loads connected, and continuity 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.