Selection, Application, and Interchangeability of Medium-Voltage Power Fuses in Motor Control Centers

Medium-voltage (MV) fuses (1-34.5 kV) of equal ratings are not all created equal. The assumed interchangeability of various vendors' MV fuses may expose the user and the MV control equipment to undue stress and danger. This paper outlines the design characteristics, operating characteristics, selection criteria, and failure modes of the MV power fuses when used in motor control applications (typically 2.4-13 kV). Also covered are application, installation, and special application considerations including MV drives and soft starters. When properly selected and applied, the MV power fuses should provide years of safe and reliable protection