What is the maximum size required for the grounding electrode conductor when connected only to concrete-encased electrodes?

The maximum size required for the grounding electrode conductor when connecting only to concrete-encased electrodes is specified by the National Electrical Code (NEC). When dealing with concrete-encased electrodes, the conductor must be adequate to safely conduct fault current and effectively ground the system.

According to NEC guidelines, for a concrete-encased electrode, a minimum size of 4 AWG copper conductor is required, ensuring that it provides sufficient capacity for fault currents while also accommodating any system requirements. This is critical for maintaining safety and operational integrity in electrical systems.

The other conductor sizes, while they may be used in other applications or configurations, do not meet the necessary requirements for concrete-encased electrodes based on the NEC specifications.