What type of conductor insulation is required for underground service conductors under NEC Article 230?

For underground service conductors, NEC Article 230 specifies the need for insulation that is rated for underground use. This requirement ensures that the conductors can withstand the moisture, soil conditions, and potential physical damage associated with being buried. Insulation designed specifically for underground installation provides additional protection against environmental factors such as water and chemicals found in the soil.

Using insulation rated for underground applications ensures safety and prolongs the lifespan of the conductors, reducing the risk of failures that could lead to electrical hazards or power outages. This makes the choice of insulation critical in maintaining the integrity and reliability of the electrical service.

Other insulation types, like indoor-rated insulation, are not suitable for underground use due to their lack of resistance to moisture and other outdoor conditions. Similarly, the notion that only PVC insulation is allowed is incorrect, as there are various types of underground-rated materials that are permissible. Lastly, stating that no specific insulation type is required contradicts the provisions established in the NEC, which aim to ensure safe and durable installations.