A mobile application including a motive power circuit including a power storage device and an electrical load; a power distribution unit (PDU) electrically interposed between the power storage device and the electrical load, wherein the PDU includes a breaker/relay positioned on one of a high side and a low side of the power storage device; wherein the breaker/relay includes: a fixed contact electrically coupled to the power bus; a movable contact selectively electrically coupled to the fixed contact; an armature operationally coupled to the movable contact; a first biasing member biasing the armature into one of the first position or the second position; and a means for selecting a down force value of the movable contact, thereby providing for a physical opening response of the breaker/relay in response to a selected current value.