Fuse Theory and Principles
A fuse is an equipment that plays a fundamental role in electrical and electronic circuitry. It is an important part of any circuit to ensure protection against the effects of an overcurrent. A fuse works by presenting an electrical circuit with a relatively low resistance when the normal current is flowing through it, but when the current exceeds a specific value, it causes the fuse element to heat up and melt. The melting of the fuse element interrupts the current flow and thus prevents any further damage to the circuit.
Fuses are fabricated from materials such as metal strips, glass tubes, wire linkages and sometimes combinations of various materials. Fuses are typically manufactured using precious metals such as silver, gold, and platinum as they possess good electrical conductivity and allow for higher current ratings than those of the other materials. Fuses are typically classified based on the type of material used, the type of element used and the type of use.
Metal strip fuses are made up of a thin strip of metal which gets heated up upon exposure to an excessive current level. The device contains a metal strip that is connected to two metal caps. The strip is connected to the two end terminals, which are the positive and the negative connection to the remaining circuitry. When an excessive current passes through the device, the pressure caused by the current heats up the metal strip, eventually causing it to break due to thermal expansion. This causes the current to shut down and the circuitry remains protected.
Glass tube fuses are made up of a specialized glass which is usually enclosed in a metal tube. The glass material contains a very small wire which bridges the two connections, allowing current to flow through. When the current level is too high the wire heat up causing the glass to melt and break. This stops the electrical circuit from further damage as well as preventing any possibility of short-circuiting.
Wire linkages are designed for applications that require high current ratings. They are made up of a metal strip encased in an aluminium tube and are connected to each other using an embedded filament wire. The wire is heated when an over current passes through it, resulting in a separation of the connections at the two ends of the tube. This creates an interruption in the electrical circuit.
The working principle of a fuse is based on the fact that when the current exceeds a given value, it heats up the metal element. Upon heating, the element reaches a point where it melts and opens the connection between the two terminals, thereby stopping the flow of current. Additionally, the fuse element is designed to cool down once the current has been interrupted, thus allowing the electrical circuit to be resumed.
In conclusion, the fuse is an important device that helps protect electronic devices from the damage caused by an excessive current and short-circuiting. It also helps to prevent surges and spikes that can reset the internal electron devices, thus ensuring reliable and safe operation. Fuses are typically found in devices such as audio, video, power and automotive systems and come in various types based on the material used and the type of use.
