Dwi, May 15, 2018
Resistors are an integral part of any electrical or electronic circuit. Resistors do not do much to clearly be identified within the circuit. Resistors as the name suggests resist the flow of current within a circuit. This is referred to as resistance and is gauged using Ohms denoted by the Greek letter omega. The amount of current that reaches other parts of a circuit is controlled by the resistors. If for instance there is too much current going to a light bulb it will be damaged. In this way a resistor is a guardian to other sections of the circuit.
Varying systems require varying levels of resistance. A custom resistor is therefore a resistor made for a specific system. It is created to cater to the needs of that particular system. When picking a resistor for a system one should know how much heat the resistor can endure before it is rendered useless. Resistors heat up when current passes through them.
A resistor with high resistance will be hotter than one with lower resistance. The material used to make the resistor is important as some materials may not be able certain temperatures. So a customer resistor should be made with consideration to how much heat is likely t be produced while it is in use.
The accuracy of a particular resistor is known as tolerance. It is not possible to create a custom resistor that is absolutely correct for a system and the current flowing through it. The tolerance or accuracy of a resistor is given in terms of plus or minus a specific percentage. A good example would be a 5 % resistor that has a value of 200 ohms will exhibit a resistance of between 210 ohms and 190 ohms.
The main materials used to make custom resistors are carbon, ceramics and metals. As noted above resisters build up heat as current flows through them. The material you select should be able to withstand the heat without the risk of melting or catching fire. Many of the Available resistors in the market are made of carbon and metal.
Custom resistors can come in either hole-mount or surface mount. The main material for Through-hole mount are either made of carbon, metal film or very thin metal foil. The former is much cheaper. The Surface mount resisters are made of either thin or thick metal foil. Thick foil resistors are cheaper than thin foil resistors. Variable resistors are good option to the static resistors. This is because they can be easily regulated between a wide range of values. These are called rheostats and are common in components such volume knobs.