Fuses and circuit breakers are designed to interrupt the power

to a circuit when the current flow exceeds safe levels. For

example, if your toaster shorts out, a fuse or breaker should

"trip", protecting the wiring in the walls from melting. As

such, fuses and breakers are primarily intended to protect the

wiring -- UL or CSA approval supposedly indicates that the

equipment itself won't cause a fire.

Fuses contain a narrow strip of metal which is designed to melt

(safely) when the current exceeds the rated value, thereby

interrupting the power to the circuit. Fuses trip relatively

fast. Which can sometimes be a problem with motors which have

large startup current surges. For motor circuits, you can use

a "time-delay" fuse (one brand is "fusetron") which will avoid

tripping on momentary overloads. A fusetron looks like a

spring-loaded fuse. A fuse can only trip once, then it must be

replaced.