If flexibility or movement is required after installation, is an equipment grounding conductor necessary in flexible metal conduit?

In the context of flexible metal conduit (FMC), the requirement for an equipment grounding conductor can vary based on installation circumstances. When flexibility or movement is necessary after installation, the use of FMC does not inherently require an equipment grounding conductor if certain conditions are met.

Flexible metal conduit is designed to provide both physical protection for conductors and some degree of flexibility that allows for movement without compromising the integrity of the electrical system. If the FMC is used in a manner that does not introduce grounding issues or if the system is properly grounded at other points, an additional equipment grounding conductor is not mandated.

This is particularly true in installations where the flexibility of the conduit is required for dynamic applications, such as in movable machinery or equipment. Consequently, while the conduit itself can serve as a path for grounding under specific conditions, it may not necessitate an additional grounding conductor if existing grounding methods are already effective.

The distinction lies in understanding both the function of the conduit and the overall grounding strategy employed in the installation. Therefore, the assertion that an equipment grounding conductor is not required aligns well with the practical use of FMC in flexible applications, given that appropriate grounding is still maintained through alternate methods.