Cartridge fuse with indicator, particularly central indicator

摘要

A fuse unit whose working fusible element (1) is monitored by an indicator fuse element (2), connected mutually electrically in parallel with it, and including an indicator (4). The indicator (4) is joined to a shape-memory element (3) and is made movable in such a way that with change in shape of the shape-memory element, the indicator (4) carries out a movement which is utilised as an indication. The shape-memory element (3) is accordingly selected so that its activation temp. lies below its melting temp.