133150R4 is a S&C Electric Company SM-5 fuse refill assembly designed for medium‑voltage SM‑5 fuse holders. It is rated for 100 A with a nominal voltage of 25 kV and a maximum of 27 kV, making it suitable for outdoor distribution substations that protect transformers, capacitor banks, and cables. This refill unit functions as a direct replacement element within the SM‑5 family, enabling proper coordination of protection without replacing the entire fuse base.
