A direct current interrupting switch assembly comprising a primary conductor and a secondary conductor integrated with a direct voltage source and a load. The primary conductor of the switch assembly has two branches, the first branch including a fuse with a melting member and the second branch including a pyroswitch with an interrupting member. In a first position, the second branch of the primary conductor is uninterrupted, and the interrupting member is a sufficient distance apart from the secondary conductor. When the interrupting member is moved to a second position, the current in second branch of the primary conductor is interrupted and the interrupting member contacts the secondary conductor of the switch assembly.