Attach a ground wire from one of the threaded studs (A) at the bottom of the housing, to the mounting plate (B). The ground resistance between all system parts shall be < 0. Power from factory ground must be installed by a qualified electrician. Each DISTRIBUTION BOX and controller must be grounded. Whether you're a seasoned pro or just starting out, this comprehensive guide will give you practical. Control panels typically feature an input power feed having a grounding conductor that is ultimately bonded to the electrical enclosure. This guide discusses some of the common practices on how to ground electrical enclosures: Earth grounding may not be an activity you will handle directly if. The correct connection method of Distribution box grounding wire mainly includes the following steps: 1. Preparation: First, you need to prepare some necessary tools, including grounding wire, grounding rod, voltmeter, insulating gloves and insulating tools.