There are several types of resistors available for use in products, machinery, vehicles, sensors, and anything else that functions via the dissipation of power. Each type has a multitude of sizes, tolerances, and possible casing options. Customization is also available for most resistors. Selecting the right resistor for a new product or application can be confusing. Knowing the differences in resistor capability and comparing that to the end result desired, can help determine which one to select. Support and selection assistance from companies that manufacture resistors is also helpful.
The first consideration is whether the application requires more precision or power. If tight resistance tolerance and stability is needed to ensure function, precision resistors are the best options. The power rating is limited, as is the operating temperature when using this type of resistor. In order to optimize power dissipation and increase temperature limits, power resistors are the better option. Some manufacturers have the engineering, design, and production capabilities to modify existing resistors to create a high power resistor. The result can be used to improve current electronics, allow automated machinery to operate faster, and increase the range of remote controls for alarms and garage door operators. Custom made resistors can also be developed to operate more efficiently. A current sense resistor is another option to prevent power loss while reducing heat generation.
The next thing to decide is whether to use wire-wound resistors or those that utilize metal film. The wire-wound variety have been utilized for a long time. That is due to accuracy and stability. New technology has not found a substitute that works better than this older design. The TCR, or temperature coefficient of resistance, is also unmatched by metal film designs. The TCR can also be customized to suit special applications. The metal film type of resistor responds faster and tends to be smaller in size. They are also more cost-effective, especially in high volumes. The thickness of the film dictates the temperature tolerance of the resistor.
Most resistor companies provide high volume production to keep pricing competitive. Since resistors are used in so many products, large productions are the most efficient. A few companies specialize in smaller volumes of customized production. Ordering to specifications can easily be completed online. The average lead time for custom resistors is approximately four to six weeks. That is helpful to small manufacturing businesses, inventors and developers, and innovators that need to test the performance of the custom resistor in a product prior to mass production.