Install protective grounding on the distribution box

26 mm 2 (10 AWG) ground wire must be used, and in all other markets a 6 mm 2 must be used. Each DISTRIBUTION BOX and controller must be grounded. Grounding of the units: Attach a ground wire from one of. 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. This helps to reduce the potential difference that exists between. This technical article covers protective grounding requirements for steel tower and wood pole supported transmission and distribution lines, and insulated power cables. ected to shield it from lightning. It is located at an elevation such that a line passing through the static wire and the outermost conductor below it is at a 30° aximum angle with a vertical line.