Usually, the only way to check whether a fuse has blown is to replace
it. But electricity supply engineers have a special problem: they must climb
a pole to check fuses.
Cooper Industries of Houston, Texas, has filed a European patent application
(430 604) on an industrial fuse which gives a sign when blown. The idea
could be adapted for domestic fuses.
The new fuse has a spring which is held under tension by the fuse wire.
When there is an electrical overload the wire gets hot and breaks, releasing
the spring. The spring pushes a coiled streamer, like a party decoration,
out of the end of the fuse cylinder. So the blown fuse immediately displays
itself in decorative fashion.
