High speed fuses provide superior protection or isolation for components such as diodes, silicon controlled rectifiers (SCRs), Gate torn-Off Thyristors (GTOs) and IGBTs and in light and heavy harsh DC traction applications as high as 4000Vdc and 10,000A. Also used for the protection of DC link/power converters. Optimized dimensions and materials allow for excellent thermal dissipation for high current cycling enviroments, or heavy duty applications.