When a transformer that is supplying service is located outside a building or structure, the minimum number of additional grounding connections that must be made to a grounding electrode is:
- One
The National Electrical Code (NEC) requires a minimum of one additional grounding connection to a grounding electrode when a transformer is located outside a building or structure. This connection ensures proper grounding and safety in the electrical system. It helps to prevent electrical hazards and ensures the effective operation of the transformer.
Having one additional grounding connection helps to establish a solid electrical ground and reduces the risk of electrical faults or shocks. It is an essential safety measure to protect both the transformer system and the building it serves.
Therefore, the correct answer is one additional grounding connection to a grounding electrode when a transformer supplying service is located outside a building or structure.
