Must grounded conductors for a premises wiring system be electrically connected to the grounded conductor of the supply system?

The requirement for grounded conductors in a premises wiring system to be electrically connected to the grounded conductor of the supply system is rooted in the need for safety and the proper functioning of electrical systems. When a grounded conductor is connected to a grounding system, it helps ensure that fault currents can safely return to the source, thereby facilitating the operation of overcurrent protection devices, such as circuit breakers or fuses. This connection is crucial to maintaining safety standards, as it helps prevent electric shock hazards and enhances the overall stability of the electrical system.

In addition, this practice aligns with the National Electrical Code (NEC) regulations, which establish clear guidelines for grounding and bonding to ensure that electrical systems operate safely and effectively. Ensuring that grounded conductors are correctly bonded to the supply system creates a reference point for voltage and minimizes the risk of transient voltages that can lead to equipment damage or hazards.

This connection is not merely a suggestion; it is a fundamental requirement in electrical installations to ensure electrical safety and reliability.