The failure rate of resistors is relatively low compared to other electronic components, so we generally evaluate that the lifespan of resistors is relatively short. However, the failure rate will increase during high-pressure and high-temperature conditions, so in some scenarios, we still need to carefully evaluate the lifespan of the resistor.

Factors affecting the lifespan of resistors:

(1) Temperature, too high a temperature can quickly cause it to burn out.

(2) The acidity and alkalinity of the environment directly corrode the resistance and cause its damage.

(3) If the external force exceeds a certain limit, the resistance will break.

So we need to extend the lifespan of the resistor, dissipate heat well, prevent burning, keep the environment dry, free of pollutants, and avoid external forces. A resistor with a high resistance value has a relatively long lifespan. The resistance value of the M Ω level is very high. When used in low voltage, due to low power consumption and minimal impact on the working environment, the service life is generally very long and does not require special attention (compared to other components such as electrolytic capacitors). Most problems arise during high-pressure operation. During high-voltage operation, there are considerable requirements for the manufacturing process and materials used in resistors. To consider using power, it is often necessary to use the maximum possible power (the safe power value of the resistor is more than twice the actual working power, and some products are designed improperly, often using power that is too close to the rated power value of the resistor), so temperature tolerance is the most basic requirement. Instantaneous pulse voltage and surge current can also cause fatal damage to resistors. For products with poor soldering of pins and defective insulation processes, they will quickly collapse and burn out. Properly used resistors have a service life of over 100000 hours, which is not a problem.

So high resistance resistors like 1M Ω can distinguish between high voltage and general use. The price of high-voltage specialized resistors is several times higher than that of ordinary resistors, but resistors are ultimately low-priced components, and the number of resistors used in high-voltage is not very large. For scenarios with high voltage and high current, leaving sufficient derating design can effectively improve the lifespan of the resistor.

So, the lifespan of resistors must be different when in use and when not in use. Resistors have different lifespans in different usage scenarios. So there are two lifespans for resistors: load life and shelf life.

The full name for resistance load life should be Load Life Stability. The percentage change in resistance value of a resistor under long-term rated power load, representing the parameter of the lifespan of the resistor.

The so-called resistance load life is the estimated life of a resistor when it is used. In fact, the load life of a resistor is related to these three factors that affect the resistor: the power, temperature, and usage time of the resistor. The active period of resistance value change is in the first few hundred hours of use, and it tends to stabilize as the use time increases. This is because over time, the resistance element itself tends to stabilize, or the stress between the resistance element and the matrix gradually releases. The indicator of resistance load life can only be obtained through sampling testing, and the expected life of the product can be calculated through sample testing. Because this type of testing requires at least 1000 hours, aerospace applications may require up to 10000 hours of testing, and this type of testing is a destructive experiment.