How should underground service conductors be installed according to NEC Article 230?

The correct answer emphasizes the necessity for proper installation of underground service conductors, which must be done in non-corrosive conduits or direct burial, provided they meet specified depth requirements. According to NEC Article 230, underground service conductors are subject to certain conditions to ensure safety and longevity. When buried directly, they must be installed at a depth that protects them from potential physical damage and environmental factors.

Using non-corrosive conduits offers additional protection against moisture and chemical reactions that can occur in the soil, prolonging the life of the conductors. This is crucial in locations where corrosive elements could negatively impact the insulation and wiring inside the conduits.

Maintaining the required burial depth is also vital; it helps reduce risks associated with accidental penetration, like digging or other activities that might disturb the area. This structured approach is critical in ensuring compliance with safety standards and safeguarding the integrity of the electrical system.

The other approaches mentioned do not adhere to these important safety and material integrity requirements, which is why they are not suitable choices for the installation of underground service conductors.