The rating of fuse fitted within a plug depends on the power rating of the device to which it is attached. The fuse must be compatible with currents slightly higher than those used to operate the device. Obtain the tools you will need - typically fuse wire, wire cutters, a screwdriver and a torch so you can see what you are doing

The definition of a D-type fuse is a miniature circuit breaker that trips when the current exceeds the rated level by between ten and 20 times. Therefore, a 16 amp Type D breaker will trip if the current reaches between 160 and 320 amps. Type F FusesYou can use Ohm's Law to calculate the required rating for a fuse. Divide the power of the attached device (measured in watts) by the voltage of the power supply. If the result is a fraction, round this up or down. Despite their everyday name, domestic fuse boxes now typically contain circuit breakers rather than fuses, and they are more formally known as consumer panels. However, if your property still contains a traditional model, here is how to go about changing the wire in a fuse if it blows and cuts the power to one of the circuits that run through the building. Unsurprisingly for such a widely used component, fuses are available in a multitude of models and voltage capacities for use in different industrial, manufacturing and electronic settings. The time taken for a particular type of fuse to blow is called the fuse speed. The three principal fuse speeds available are:

When a fuse blows, the electrical supply to a particular circuit is immediately cut off. This lowers the risk of fire and prevents damage to the wiring. The blown fuse can safely be replaced without the risk of electrocution. Are Old Fuse Boxes Illegal? Fuses and circuit breakers serve a very similar function - both break electrical circuits in the event of a current surge or short circuit. However, there is a crucial difference. Circuit breakers are switches, and like all switches, they can be reset once they have been flipped. Most fuses, though, can only be used a single time. Once they have blown, they must be replaced. They are, by definition, a weak link - entirely by design. For example, if an electric drill requiring a new fuse has a 700-watt rating, divide this by 230 (the standard UK mains voltage). The result is 3.04, so you will require a 3A amp fuse for the plug. Where Would a Type D Fuse Be Installed? Ultra-rapid fuses: typically used in sensitive circuitry and transistors to protect against short circuits, reacting almost instantaneously. These are also known as Very Fast Acting, Super Rapid and High-Speed fuses Striker fuses are fuses fitted with a spring-loaded striking device that can trip adjacent switches and also indicate that a fuse has blown. Type C FusesFuse boxes have a number of alternative names, including control board panels, distribution boards, breaker panels, fuse boards, and fuse panels. Domestic fuse boxes are frequently referred to as consumer units. What is a Switch Fuse Unit? Most UK plugs are fitted with a 3 amp or 13 amp fuse. 3 amp fuses are used with a range of lower power domestic goods and tools, including lamps, TVs, and drills. Meanwhile, higher power goods such as washing machines, kettles and toasters normally require a 13 amp fuse. What Happens When a Fuse Blows? A Type C fuse is actually a type of miniature circuit breaker (MCB). MCBs are a type of circuit breaker used with lower-powered circuits to cut off current in the event of an overload. Type C fuses trip circuits when the current exceeds the rated one by between five and ten times - i.e. at 100-500 amps for a 20amp device. Type D Fuses Surface mount devices (SMDs) are electrical components that sit on the surface of printed circuit boards (PCBs). SMD fuses are available in both resettable and non-resettable forms.