A Basic Guide to the Different Functions of Power Resistors
Applications that require the use of electronics often involve the utilization of some form of low-power resistors, around 1/8 watt or less. On the other hand, the use of high-power resistors is often required for applications that involve heaters, amplifiers, power conversion, dynamic brakes, and power supplies. Typically, high-power resistors have a loading rating of 1 watt or more. You also get them within the kilowatt range.
One of the basic things that you need to know about power resistors is that their power rating determines how much power they can handle safely before they start to suffer from damaging permane
nt consequences. You can determine how much power a resistor dissipates with the application of Joule’s first law. Simply put, you multiply the current with the voltage. The power that comes from the resistor is transformed to heat. At the same time, it increases the temperature that the resistor gives off. The temperature coming from the resistor continues to go up until the point where the heat that dissipates through the surrounding environment, circuit board, and air balances the heat that the resistor generates.
As much as possible, you should keep the temperature of the resistor down if you don’t want to damage the resistor as a whole. At the same time, doing so enables the resistor to deal with greater currents better without any damage or degradation. The use of a power resistor above its rated temperature and power can have negative consequences on it. Some of these consequences include a reduction in the operating lifetime, a shift in resistance value, and an open circuit. With temperatures of resistors being so high, they may be on fire, and worse, the materials that surround them will also catch fire. For the avoidance of these negative effects, manufacturers make sure to de-rate power resistors, depending on the operating conditions that are expected from them. Get the best current shunt resistor company on this site.
Generally, power resistors are bigger than their lower power equivalents. A bigger size guarantees that heat will be dissipated properly. Moreover, a larger size ensures that users get mounting options, especially for heat sink applications. When it comes to high-power resistors, on the other hand, they come in flame-retardant packages. This helps reduce the possibility of failure, which leads to hazards.
In the present market, you can choose from an array of high-power resistors. Each kind offers variations in terms of its capabilities, especially for different applications. Wirewound resistors are one of the most common types of resistors. You can find them in different variants. Some of them include chassis-mount, axial, radial, and surface mount designs. The first example ensures that optimal levels are reached in terms of heat dissipation. Get more details here: https://www.britannica.com/technology/resistor.