If conductors are installed in parallel in the same raceway or cable tray, a single wire-type conductor shall be permitted as the equipment grounding conductor based on the overcurrent protective device for the _____.

• A. Feeder
• B. Branch circuit
• C. Service
• D. Subpanel

Answer: (A)

When conductors are paralleled in the same raceway or cable tray, a single equipment grounding conductor can be used to bond the whole set, and its size is determined by the overcurrent device protecting that feeder. The reason this works is that the feeder’s fault current will return through that one grounding path back to the source, and sizing the GEC based on the feeder OCPD ensures it can carry the fault current long enough for the protective device to trip. This approach is an allowed exception specifically for feeders (and their subfeeders), where the main OCPD at the source governs fault current. It isn’t the standard arrangement for branch circuits or for service grounding practices, so the best match for the given scenario is the feeder.