These locations are usually marked with grounding symbols for easy cable crimping. Connection Points: Dedicated bolts welded to the inside of the door panel must be tightened. If you've ever found yourself scratching your head over whether that metal door on your distribution cabinet really needs a grounding wire, you're not alone. Your boss might insist on it, while your. Power from factory ground must be installed by a qualified electrician. Each DISTRIBUTION BOX and controller must be grounded. During fault conditions, low impedance results in high fault current flow, causing overcurrent protective. 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. Make sure all tools are intact to prevent accidents during the grounding. Proper electrical enclosure grounding is a vital facet for providing safety, performance and uptime.