What Is The NEC Definition Of A Dwelling Unit? NEC Article 230.67 definition of dwelling unit includes your home. Per the National Electric Code (NEC 2020), a dwelling unit is a single unit, providing complete and independent living facilities for one or more persons, including permanent provisions for living, sleeping, cooking and sanitation. Your home is a dwelling unit as well as Hotels, Hospitals, Dormitories, Barracks, Assisted Living Facilities and Apartment Buildings. The NFPA 70 Article 230.67 states: . (A) Surge-Protective Device. "All serivces supply dwelling units shall be provide with a surge-protective device (SPD)." The M50-120T-A is installed via a 2-Pole 30A circuit breaker and will not only protect the main service panel but all smart applicances and electronics in the home like your oven, refrigerator, dishwasher, security system, televisions, ev chargers, etc... This protector is what is referred to as a "Whole House Surge Protector". In addition, the NEC 2023 Article 230.67 futher states that the location for installation of the SPD, the SPD type and Replacement of Service Entrance Equipment shall follow these rules, (B) Location. "The SPD shall be an integral part of the service equipment or shall be located immediately adjacent thereto" (C) Type. "The SPD shall be a Type 1 or Type 2 SPD." (D) Replacement. "Where service equipment is replaced, all of the requirements of this section shall apply." Examples of Dwelling Units Article 230.67 Surge Protection for Hotels Article 230.67 Surge Protection for Hospitals Article 230.67 Surge Protection for Barracks Article 230.67 Surge Protection for Apartment Building Article 230.67 Surge Protection for Row Houses 10108 USA Today Way Miramar, FL 33025 USAContact us to develop a surge mitigation solution for your application www.citel.usWhere to purchase Citel SPD's