JTD ID Series UL Class J Time-Delay Fuses with Indication. The Littelfuse POWR-PRO JTD ID Indicator Class J fuse provides visual blown fuse indication and maximum protection in a compact package. The compact Class J package was designed specifically for circuits where space is at a premium. The current limiting time delay JTD ID offers a patented true dual-element design that is ideal for use in circuits with high inrush currents. Superior performance characteristics of JTD ID Indicator fuses reduce nuisance fuse opening and the blown fuse indication reduces downtime and increases safety. Applications: Fused combination motor controllers to provide IEC Type II (no damage) motor branch-circuit short-circuit and ground fault protection, Motor control centers, Transformer protection, Protection for UL Listed series-rated molded case circuit breaker panels, General purpose circuits like mains, feeders and branch circuits, especially when space is at a premium.