The 487 Series is a 420VAC/420VDC rated 5x20mm fastacting ceramic body fuse, designed to ensure the best coordination between a power supply unit (PSU) and an electrical circuit breaker panel during short-circuit and overcurrent faults. When installed in a PSU, the 487 series fuse opens faster than the circuit breaker and removes the problematic PSU while preventing the circuit breaker from shutting down other critical systems. With 420VAC characteristics, the 487 Series is well suited for highenergy applications like 3-phase power supplies, inverters, and ballasts. With 420VDC characteristics, it is optimal for high-voltage DC power grid in data centers, telecom applications, and intelligent commercial buildings.