Are non-current-carrying metal parts of cord-and-plug-connected equipment required to be grounded when they are insulated?

In grounding and bonding practices, the requirement for non-current-carrying metal parts of cord-and-plug-connected equipment to be grounded largely depends on their condition and the likelihood of them becoming energized. When these metal parts are properly insulated, they do not present a risk of electrical shock under normal operating conditions. Therefore, grounding those parts is not necessary in certain scenarios, specifically when insulation effectively prevents inadvertent contact with live parts.

The rationale behind this is rooted in safety standards designed to mitigate hazards while allowing for flexibility in equipment design. If the insulation is intact and functions as intended, the likelihood of these metal parts carrying current is significantly reduced, thus minimizing the need for grounding.

While grounding is a vital safety measure for preventing electrical shock, it is not universally required for all non-current-carrying parts; the specific conditions under which grounding is necessary will vary depending on factors like the type of equipment and its intended use. This understanding emphasizes the importance of proper installation and regular maintenance of potentially hazardous equipment to ensure that insulation remains effective.