Equipment Grounding Conductor Sizing

Minimum EGC size from overcurrent device rating.

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Details, formula, and sources

EGC size from NEC Table 250.122, keyed to the upstream OCP rating; min size driven by OCP, parallel runs sized per NEC 250.122(F).

NEC 2023 (NFPA 70). Section 250.122 and Table 250.122.

Free read-only access at nfpa.org/freeaccess.

Estimate. AHJ and licensed electrician govern. Verify against the NEC edition adopted in your jurisdiction.

Field names used by the API: ocpd_A, material, egc_awg

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