One Alternate to the Secondary Network and Underground Systems

Equipment is available which provides a single alternative for secondary network and vault services. Recent development of a Front Operable Underground Type Single Phase Distribution Transformer with Separable Insulated High-Voltage Connectors makes possible the use of a single system for vault type installations. Three phase service is obtained by banking these units. This paper describes this type transformer, its operating features, and application. Front operability allows this transformer to be switched employing the same tools and procedures used for padmounted equipment. Comparisons are made between installations using this front operable transformer and ones with alternate equipment.