Here is the simple truth: you do not ground a plastic electrical box. The material is an insulator, so there is nothing to ground. Your real task is grounding the device installed inside it — the outlet or switch. It's crucial to understand that you don't directly ground the plastic box itself; instead, the purpose is to maintain a safe grounding path for the devices and circuits within the box, which is achieved by ensuring that any metal components within or attached to the box are properly grounded back. However, with plastic distribution boxes, the grounding process can be somewhat complicated. Preparation: First, you need to prepare some necessary tools, including grounding wire, grounding rod, voltmeter, insulating gloves and. Grounding is an essential safety feature in electrical wiring, and it is crucial to understand the differences between grounding wire in metal and plastic boxes. This requires that the grounding connection be established directly and solely through the wiring itself to. A plastic box has no metal body to bond, so ground the circuit by joining the bare or green wires and adding a pigtail to each device.
[PDF Version]