Improving fuse reliability in critical control circuits

Due to the critical nature of control-circuit fuse reliability in nuclear generating stations and the significant number of failures being experienced, an investigation of control-circuit fuse failures is presented. This analysis indicates that the Class-H fuse type commonly used in generating station control circuits is susceptible to failure for a number of reasons. Improved fuse types are discussed. Failures of instrumentation-type fuses are also analyzed and the results are discussed. Suggestions are provided for improving control-circuit fuse reliability