NRS20 – GOULD 20A 600V CLASS K5 ONE-TIME FUSE

Class K5 and Class RK5 fuses share the same 600V, 10kA interrupting rating, but Class RK5 fuses have a rejection feature that prevents them from being installed in non-rejection holders. The NRS20 is a non-rejection Class K5 fuse, so it will fit standard Class H/K holders. If your holder is a rejection-type (Class RK), you'll need a Class RK5 equivalent instead. Contact us and we can help identify the right replacement.

Yes — Northern Breaker Group specializes in obsolete and hard-to-find electrical components, and the Gould NRS series remains available through our inventory and supplier network. Common cross-references include the Bussmann NON-20 and equivalent Ferraz Shawmut or Mersen one-time fuses. Reach out for a quote or to confirm stock availability.

The NRS20 is a one-time (fast-acting) fuse and does not have a built-in time-delay. For motor branch circuit protection, motors draw a high inrush current at startup that can nuisance-blow a fast-acting fuse. A Class RK5 or Class RK1 time-delay fuse is generally recommended for motor applications per Canadian Electrical Code requirements. The NRS20 is better suited for feeder protection, lighting circuits, or transformer primary protection where no inrush is expected.