Grounding Grids Information
Grounding grids, also called multipoint grounding systems, are grounding arrays that electrically ground structures. Applications for grounding grids include pipelines, substations, transformers, large motors, computer stations, and high-voltage power lines. They are often used with lighting protection.
Grounding grids rely on conductive mesh or sheets to create several paths for electrical energy to find its way to ground. Grounding grids limit potential differences between pieces of equipment and stop ground loops. They also reduce mains hum and minimize touch potential. Grounding grids are critical in static discharge and lightning protection.
Grounding grids, mats, and sheets are commonly made of copper-clad wire and solid copper grounding electrodes with bonded connections. Size and shape depend on soil resistivity, fault duration, area and geometry. Other design factors include touch potential and step potential.
Substation Grounding 101 (pdf)