If a feeder is protected at 400 amperes, what is the minimum size aluminum equipment grounding conductor required?

To determine the minimum size aluminum equipment grounding conductor required for a feeder protected at 400 amperes, it is essential to reference the National Electrical Code (NEC) guidelines concerning grounding and bonding. The NEC provides specific tables that specify the minimum wire sizes for grounding conductors based on the rating of the overcurrent protection device protecting the conductor.

In the case of a feeder with a 400 ampere protection rating, one must look at a table or section in the NEC that correlates the size of the grounding conductor to the amperage of the feeder circuit. For aluminum conductors, the NEC specifies that a minimum of 1 AWG is required for equipment grounding conductors in feeders rated at 400 amperes.

The choice of 1 AWG ensures that the grounding system can effectively handle potential fault current, allowing for safe operation and reducing the risk of electrical shock or fire. This adherence to the code is critical for maintaining safety standards in electrical installations. The size specified not only meets the minimum requirements but also takes into account the characteristics of aluminum as a conductor. Thus, selecting 1 AWG for the equipment grounding conductor is consistent with the necessary safety protocols outlined in the NEC.