방법 to 사용 a 디지털 멀티미터 to check the line fault point
1. 시각 검사.
당신 할 수 있다 터치 그 배터리, 저항기, 트랜지스터, and integrated blocks to see if the temperature rise is too high. If the newly installed battery heats up, the circuit may be short-circuited. In addition, the circuit should also be observed for disconnection, deoldering, mechanical damage, etc.
2. 파형 분석.
사용 an 전자 오실로스코프 to 관찰 the voltage waveform, amplitude, period (frequency), etc. of each key point of the circuit.
For example, if the clock oscillator is oscillating, if there is no output from the oscillator, it means that the internal inverter is damaged, or the external components may be open.
3. 측정 구성 요소 매개 변수입니다.
For components within the fault range, conduct online or offline measurements, and analyze parameter values. When measuring resistance online, the influence of components connected in parallel with it should be considered.
4. 숨김 문제 해결.
5. 감지 작동 전압 at 전체 레벨.
Detect the working voltage of each point and compare it with the normal value. First, ensure the accuracy of the reference voltage. It is best to use a digital multimeter of the same model or similar to measure and compare.
여부 the measured voltage is DC or AC voltage, if it is AC voltage, the filter capacitor in the ac/dc conversion circuit may be broken; if it is DC voltage, there may be a problem in the reference voltage circuit. It is recommended that you purchase a copy online if you have the conditions: Digital Multimeter Practical Measurement Techniques and Troubleshooting Book. Come and see.
In most cases, the damage of the digital multimeter is caused by the wrong measurement position. For example, when measuring the AC mains, the measurement position is selected to be placed in the electric barrier. In this case, once the test pen touches the mains, it will instantly damage the internal components of the multimeter. damage. Therefore, before using the multimeter to measure, be sure to check whether the measurement gear is correct. When measuring the current, if the actual current value exceeds the range, generally only the fuse in the multimeter will be blown, and no other damage will be caused. Therefore, when measuring voltage parameters, if you do not know the approximate range of the measured voltage, you should first set the measurement gear to the highest gear, and then change gears after measuring its value to obtain more accurate values. If the voltage value to be measured is far beyond the maximum range that the multimeter can measure, it should be equipped with a high-resistance measuring probe. Such as detecting the second anode high voltage and focusing high voltage of black and white color TV.
