Neutral wires (white/gray) must land only one wire per screw terminal on the neutral bar, while some ground bars may accept two or three equipment grounding wires (bare/green) per terminal, depending on specifications. Because it is a current-carrying conductor, the neutral wire (and the neutral bar) is referred to as the “grounded conductor” in electrical codes. It should never be treated as de-energized, even though it is nominally at ground potential. In all other locations like subpanels or downstream distribution points, ground and neutral must be kept separate to prevent dangerous current paths, equipment. The service neutral conductor provides the effective ground-fault current path to the source to remove dangerous voltage from a ground fault by opening the circuit overcurrent protective device (OCPD) [250. That grounding system connects to earth through ground rods, metal water pipes, or a concrete-encased electrode. You're standing on that same earth.
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