The following guidelines should be observed when grounding a cabinet: An unpainted earth reference plane or rail must be installed on the floor of the cabinet for the conventional reference potential. All metal parts of the cabinet are connected with each other. At least one ground terminal at the shell of the shelf and power box (or power distribution box) should be properly connected to the ground. Grounding refers to connecting electrical equipment to a common reference point within a system—typically the neutral point of a power supply. The primary purpose is establishing a zero-voltage reference point for circuit operation and protecting sensitive electronic components. " The process of connecting two or more conductive objects together by means of a conductor so that they are at the same static.