When inspecting the interior of a stainless steel outdoor electrical box distribution box, pay attention to the copper or tin-plated terminals on the base plate or side walls. These locations are usually marked with grounding symbols for easy cable crimping. Power from factory ground must be installed by a qualified electrician. Each DISTRIBUTION BOX and controller must be grounded. Grounding of the units: Attach a ground wire from one of. Safety of Personnel: By safely channeling fault currents into the ground, proper grounding helps to reduce the risk of electric shock to personnel. This helps to reduce the potential difference that exists between conductive parts and the earth. You can use any multimeter, depending on what you have. It is convenient to use, and. How to check if an area is grounded? Use a multimeter, receptacle tester, and visual inspection of bonding/earthing, ground rod, and service panel; verify ground resistance and continuity per NEC safety guidelines.