For a 3-phase, 4-wire delta connected system, what must be done to be compliant?

In a 3-phase, 4-wire delta-connected system, it is necessary to use a neutral conductor as a circuit conductor to ensure compliance with grounding and bonding practices. The neutral conductor serves as a return path for unbalanced loads and is essential for maintaining system stability and safety. It allows for the distribution of electrical power while providing a reference point for voltage and ensuring that the system can function correctly under varying load conditions.

Using a neutral in this manner helps to reduce the potential for overvoltage conditions that can occur due to unbalanced loads in a delta system. Additionally, it is crucial for providing a means for properly grounding the system, protecting both equipment and personnel from electrical faults. This connection is also in line with the National Electrical Code (NEC) requirements, which emphasize proper grounding and bonding practices to enhance safety in electrical installations.

In contrast, the other choices do not meet the necessary criteria for compliance in a delta-connected system, as they fail to address the need for a neutral conductor essential for grounding and safe operation in such configurations.