Testing and Certification of Medium Voltage Control Centers to Arc Resistant Standards

Improved medium voltage control equipment designs, including enhanced structural protection systems, have continued to evolve in support of improved personnel protection. Recent changes to some standards, such as the NFPA-70E, have emphasized the need to look for improved safety compliance to mitigating the risks associated with the operation and maintenance of electrical equipment. The requirements for employee safe work practices have all targeted reducing the risks of electrical arc hazards. However arcs accompanied by explosions continue to occur in electrical systems. Factors such as inappropriate human interaction with the equipment, equipment malfunctions as a result of misuse or lack of regular maintenance or unforeseen events continue to contribute to the unexpected release of explosive electrical energy in the workplace. This paper outlines the details surrounding the testing of medium voltage (MV) control center equipment to permit it to be certified to present arc resistant standards. The intent of this paper is to improve the understanding of the dynamics of an arc fault and how new arc resistant equipment designs can reduce personnel from exposed to electrical arc hazards in industrial settings