SMD Power Fuses are especially suited for protecting transformers, capacitor banks, and cables in outdoor distribution substations through 34.5 kV. They incorporate precision-engineered nondamageable silver or nickel-chrome fusible elements with time-current characteristics that are precise and permanently accurate — assuring not only dependable performance, but also continued reliability of system coordination plans.
With SMD power fuses, source-side devices may be set for faster operation than practical with other power fuses or circuit breakers, thereby providing better system protection without compromising coordination.
Type SMD-20 and SMD-40 Power Fuses (View Photo) are offered with maximum continuous current ratings of 200 and 400 amperes, in a variety of fault interrupting ratings. They’re available in a wide variety of ampere ratings, in four different speeds: S&C “K”, Standard, Slow, Very Slow, and “DR” (SMU-20 only). This broad selection of ampere ratings and speeds permits close fusing to achieve maximum protection and optimum coordination.