Different Types of Fuses and their Uses
Fuses work to prevent accidents caused by sudden spikes in electrical current, in hydraulic mechanism a fuse acts as a valve to prevent loss of fluid pressure and that, in some other cases it acts as an isolated process of setting off explosives. All the types of fuse are intended for the single goal of safeguarding people from accidents.
Construction and the Mechanisms of Fuses
- Regular construction of fuse comprises of a metal band of a small cross segment as against that of circuit conductors, mounted among a pair of electrical terminals and enclosed by a fireproof case.
- Fuses are fitted on the circuit and in normal conditions it will allow the electric current to pass through it without any interruption.
- Fuse in electrical and electronics language is a low resistance component that works as a sacrificial device that destroys itself in case of electrical over current thereby preventing accidents.
- In cases when there is power fluctuation and an over current stream enters the circuit and strike the fuse, excess heat is generated which burns the fuse thereby discontinuing further flow of electrical current into the system.
Main Types of Fuses
Fuses available in the market are of different shapes, sizes and they carry a similar kind of design. The only thing that makes fuses different from one another is the mechanism on which they work. Likewise, there are below mentioned few types of fuses available in the market to meet varied purposes:
A Thermal fuse is used in heat producing domestic appliances like heater, oven, microwave, dryers and many other countertop appliances.
- These are designed to break off the circuit if the internal heat crosses danger level.
- They act as sacrificial component in cases where circuit breaker fails to work.
- Thermal fuses are made of fusible heat that is a responsive material component, like a plastic pellet. When the temperature rises above the danger level, the component gets activated and melts which enables the circuit to break.
- They can be used only for one time; once they get activated, they are replaced.
These are widely used in the construction of motor vehicles. They play a vital role in functioning of various vehicle parts like headlights, side signals and horn.
- The basic function of automotive fuse is to safeguard internal wiring and electrical devices fitted in a motor vehicle.
- Automotive fuses are of four types i.e. blade, bosch, limiters and fusible links.
- The type of fuse to be used in automotives is decided on the basis of voltage requirement, current demands and type of application for electrical circuit.
High voltage Fuses
As the name suggests, these are used on electrical systems ranging up to 115000 volts AC.
- High voltage fuse safeguards transformers fitted on electrical equipments for measuring electricity and is also used on small transformers.
- In order to get reliable results from them, they are constructed out of tin, copper, or silver material.
- High voltage fuses are designed to interrupt power as high as 63 KA.
Thermo plastic conductive element known as PPTC is used in construction of resettable fuse which helps to break circuit on instances of over current.
- As the name says, resettable fuse is self resetting. When the circuit breaks and current is detached, it cools down and relapses back to regular low resistant power circuit.
- They are widely used in applications where replacing fuse is difficult like aeronautical and atomic purposes.