Overcurrent protection alternatives for underground distribution systems

Pad-mounted switchgear that is applied on underground distribution systems effects many aspects of electric utility service. Some of these include overcurrent protection characteristics, the ability of the line service crews to quickly restore service after a fault, the overall reliability of service to the customer, and, to some degree, the cost of the electric service to the customer. The user must develop a system design philosophy and then determine the equipment features needed to help meet the goals of the chosen system design. Since these goals may vary with the type of load being served, equipment features that may be selected are discussed for single phase and three phase services. The application benefits of pad-mounted sectionalizing switchgear, pad-mounted fused switchgear, and pad-mounted vacuum fault interrupter switchgear are compared in these applications