Many of us are familiar with the old screw in fuses. And those that have a fuse panel know that if the 15 amp fuse keeps blowing you can screw in a 20 amp, 25 amp, 30 amp fuse until the fuse stops blowing.
This is where the problem lies. The fuses are rated for the wire it is protecting. Our standard lights and receptacles work off a 14 gauge wire. The wire is rated to carry a maximum of 15 amps. So when we plug in too many devices on one circuit the fuse becomes overheated and ‘blows’. By using a larger fuse we may stop the problem of the fuse blowing all the time but the wire is rated to carry only 15 amps. Now that we have used a larger fuse the wire becomes overheated as it is working beyond capacity. These overheated wires are running through wood studs in the walls. The potential for fire now exists.
This is why the insurance companies would like the panel changed over from fuses to breakers. They know that the home will be much safer with a new breaker panel than the old fuse panel.