Considerations of Ground Fault Protection as Influenced by the Occupational Safety and Health Act and the Mining Enforcement and Safety Administration

The first step in recognizing the necessity of low voltage ground fault protection was taken by the 1971 National Electrical Code (NEC), Section 230-95. With the passage of the Occupational Safety and Health Act (OSHA) of 1970, more emphasis has been placed on adherence to the code. Since the establishment of OSHA, questions have been raised as to the jurisdiction between the Occupational Safety and Health Administration and the Mining Enforcement and Safety Administration (MESA). This has resulted in both agencies considering and deciding on design standards for cement plant electrical systems. Indications are that in the future, MESA standards will also recognize the necessity of adequate ground fault protection. Since the introduction of ground fault protection in the codes, there have been arguments for and against the methods of applying ground fault protection. It is for this reason that the present code requirements are minimal. In order to provide the electrical service reliability required by modern cement plants, more extensive protection is required. The intent of this paper is to evaluate the new requirements of ground fault protection. It also examines how we, as engineers concerned with electrical power systems in cement plants, approach the problems of providing safe reliable electrical systems which meet applicable code requirements and which also function satisfactorily in relation to plant operation.