The equipment grounding conductor for PV source and output circuits must be sized according to which table?

• A. Table 250.122
• B. Table 690.47
• C. Table 300.20
• D. Table 310.15

Answer: (A)

Sizing the equipment grounding conductor follows the rule that its minimum size is tied to the overcurrent protective device protecting the circuit. Table 250.122 provides this linkage, showing the required EGC size based on the OCPD rating. PV source circuits and PV output circuits are still circuits with protective devices, so their grounding conductor must be sized according to this same table. This ensures a fault path that can carry the fault current back to the source and trip the protective device promptly without overheating the conductor. For example, a PV circuit protected by a 20-amp OCPD would require a 12 AWG copper equipment grounding conductor, per Table 250.122. Other tables address different sizing aspects (like ampacity or raceway details) and do not specify the EGC size for PV circuits, so they are not used for this purpose.