Which portion of a mobile home's grounding arrangement must use at least a 12 AWG copper conductor?

• A. Primary protector grounding terminal
• B. Main service disconnect
• C. Grounding electrode conductor
• D. Neutral conductor

Answer: (A)

The important point is that the grounding path for a mobile home must have a solid, adequately sized conductor from the main protective device to the grounding electrode. The connection at the primary protector grounding terminal is the bonding point for this path, so the conductor used there must be at least 12 AWG copper. This ensures a low-impedance route for fault current to reach the earth quickly, allowing the protective device to trip and the frame to stay safely grounded.

The other parts aren’t specified to use a fixed minimum of 12 AWG in this context: the main service disconnect’s grounding path and the grounding electrode conductor have sizes that depend on service rating and installation specifics, and the neutral is a separate current-carrying conductor that is not used as the grounding path in the same way.