What are the fault characteristics of electronic components?

1. Characteristics of resistance damage Resistance is the most abundant component in electrical equipment, but it is not the component with the highest damage rate.Resistance damage is the most common with open circuit, the resistance value becomes smaller, and the resistance value becomes very small.The first two Resistorss are the most widely used, and their damage characteristics are low resistance (less than 100Ω) and high resistance (above 100kΩ), and high resistance, intermediate resistance (such as several hundred ohms to tens of thousands of ohms).Very little damage; second, when the low-resistance resistance is damaged, it is often burnt and black, it is easy to find,When the fuse is burned out, some surfaces will blow off a piece of skin, and some will have no trace, but it will never burnt and black.According to the above characteristics, when checking the resistance, you can focus on it and quickly find out the damaged resistance.2. Characteristics of Electrolytic Capacitor Damage Electrolytic capacitors are used in large quantities in electrical equipment, and the failure rate is high.The methods for finding damaged electrolytic capacitors are as follows: (1) Look: Some capacitors will leak when they are damaged. The surface of the circuit board under the capacitor or even the surface of the capacitor will have a layer of oil stain. This capacitor can never be used again. Some capacitors will be damaged.muster,Therefore, it is important to check the heat sink and the capacitance near the high-power components. The closer to it, the greater the possibility of damage.3. Characteristics of damage to semiconductor devices such as diodes and triodes

2. Damage to triodes is generally breakdown or open circuit of PN junctions, with breakdowns being mostly short.It will be found that its PN junction forward resistance is larger than normal.The reverse resistance is large enough (relative to the positive value) to indicate that the PN junction is normal, and vice versa. It is suspected that it needs to be measured after soldering.This is because the peripheral resistance of the second and the triode of the general circuit is mostly several hundred or several thousand ohms. It can be measured by the low resistance value of the multimeter, and the influence of the peripheral resistance on the PN junction resistance can be basically ignored.When it is completely damaged, it can be removed, and the positive and negative resistance of each pin to ground can be measured compared with the normal Integrated Circuits(ICs) of the same type. It is always found that one or several of the pins have abnormal resistance.