Power resistors are used in electronic circuit to prevent electric shock or damage in case there is a power shortage. They are short-circuits that can interrupt power flow in case of a voltage imbalance. There are two forms of power resistors, which are the static type and the dynamic one. The static type does not change its voltage level when subjected to changes in the power source. The dynamic one changes its resistance value when voltage fluctuations occur.
Since voltage is an electrical charge, it affects the operation of circuits even if they are not working in extreme conditions. In order to prevent overloading, most circuits have a protection that translates the input voltage level to an output voltage, namely Vr. The protection decreases the current flowing in the circuit when the power source fluctuates beyond the threshold level.
There are several applications of power resistors in electronic circuits. The most common one is to prevent excessive or sudden voltage spikes that can be dangerous. Some devices that require a constant current level (CCL) include some medical equipment and vehicles. For example, CCL is needed for heart pacemakers in those who are working in continuous heart rhythm.
Power braking resistor in some automobiles also help protect the circuit boards from high frequency voltage fluctuations that can disrupt power flow. It may sound strange but there are some vehicles that run on alternate current or AC and some have only DC power source. If the alternator or power source crashes, the power resistors will help the vehicle start without crashing. If the car engine gets overheated because of overheating due to the high voltage spikes, the power resistors will prevent the engine from getting damaged.
However, high resistant power resistors are also useful in electronic appliances, automotive industry and industrial processes such as thermal energy recovery and desuperheating. When circuits get heated up, they need to be cooled down fast. Power resistors with higher melting points are used. This means that they do not get too hot even when reaching their critical temperatures. Since they do not get overheated and burned, they are ideal power dissipaters.
High quality power resistors are usually manufactured with various other features such as thermal expansion and thermal resistance. The resistivity value of the product indicates its ability to withstand heat. It may help determine the voltage rating of the device. Its size determines how much it weighs since a larger sized device has a lower weight. You can find more information about the types of power resistors that are available in the market through online resources. For more understanding of this article, visit this link: https://en.wikipedia.org/wiki/Resistor.