The lifespan of a chip resistor is closely related to its use. Among the resistors, it is a kind of resistor with a wide range of use. Here are some precautions for using it from several aspects.
1. In order to improve the stability of the resistance, artificial aging treatment should be carried out before use. The more commonly used aging treatment method is to add a DC voltage to both ends of the resistor, so that the power it bears is 1.5 times the rated power, and the treatment time is 5 minutes. After treatment, the resistance value is measured.
2. Before use, check the resistance and appearance of the resistor, and remove the unqualified ones to prevent hidden dangers in the circuit.
3. Before the resistor is installed, the lead wire should be tinned to ensure the firmness of the welding. Its lead should not be bent from the root to prevent it from breaking. Larger power resistors should be fixed with brackets or screws to prevent loosening and causing short circuits. The action during welding should be fast, and do not subject it to long-term heat to prevent the resistance value from changing. The mark should be upward or outward during installation to facilitate inspection and maintenance.
4. When the power of the resistor is greater than 10W, ensure that there is space for heat dissipation.
5. When storing and using, the paint film on the surface should be intact, so as not to reduce their moisture-proof performance.
When the chip resistor is damaged and there is no suitable replacement at that time, the following principles should be observed:
① Use smaller resistance resistors in series instead of large resistance resistors, or use larger resistance resistors in parallel to replace small resistance resistors.
②When low-power resistors replace high-power resistors, series or parallel methods can be used. When the resistance values of the series and parallel low-power resistors are not equal, the power shared by them should be calculated so that the total power is greater than the rated power of the original resistor.
③Substitute resistors should follow the principle of high-quality resistors instead of large-scale resistors, and high-power resistors instead of low-power resistors.