Fuse, Tri-Onic, 600 Volt AC, 300 Volt DC, 50 Amp, Time-Delay, Class RK5, TRS Series Tri-Onic TRS-R current-limiting time-delay fuses are engineered for overcurrent protection of motors, transformers, service entrance equipment, feeders and branch-circuits. The time-delay characteristics of the TRS-R safely handle harmless starting currents and inrush currents associated with todayÆs motors and transformers. 600 Volts 50 amps TRS series. This listing is for Each.