A fuse assembly having a displaceable pin assembly secured within a cap bore of an end cap of the fuse assembly. The displaceable pin assembly can include a plunger that is selectively displaceable along an axis that is non-parallel to a central longitudinal axis of the first end cap. The plunger can be selectively displaceable between an extended position at which at least a first end of the plunger is outwardly positioned away from an outer surface of the first end cap, and a recessed position at which the first end of the plunger is recessed within, or generally aligned with the outer surface of, the first end cap. The displaceable pin assembly can also include a biasing element that can bias the plunger to the extended position, and a support body that can house at least a portion of the plunger and be securely coupled to the cap bore.

A set of circuit interrupters and electrical enclosures that are configured to permit an electrical enclosure having a current rating to have connected therewith a circuit interrupter having a current carrying rating no greater than the current rating. However, a current interrupter having a current carrying rating less than the current rating of the electrical enclosure potentially may be connected therewith. Such electrical interruption equipment employs threaded studs on bus bars that are of varying sizes and/or are separated by varying distances in order to resist an electrical enclosure having a current rating from being electrically connected with a circuit interrupter having a current carrying rating greater than the current rating. Alternatively or additionally, the circuit interrupter and/or the electrical enclosure may have interference elements that physically interfere with the mounting and/or the electrical connection of a circuit interrupter having a current carrying rating with an electrical enclosure having a current rating less than the current carrying rating.