When debugging the reason for a blown fuse you can easily blow dozens of
fuses until you finally find the problem. A quick inexpensive solution is
to use foil cut into an hourglass shape wrapped around a spent fuse. The
width of the waist of the hourglass determines the rating of the foil
fuse. Under most circumstances you should keep the width less than
This solution works well on electromechanicals, but extra caution should be
used on solid state application.