The most common digital multimeter generally has resistance measurement, on-off sound detection, and diode forward voltage measurement. AC and DC voltage and current measurement, triode amplification and performance measurement, etc. Some have added functions such as capacitance measurement, frequency measurement, temperature measurement, data memory and voice reporting, which bring great convenience to actual detection work. However, due to improper use of digital square meters, components within the meter may be damaged and malfunction may occur during actual testing. Precautions when using a digital multimeter are provided for reference by beginners to prevent damage to the digital multimeter as much as possible.
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1. ใน ส่วนใหญ่ กรณี, the damage of the digital multimeter is caused by the wrong measurement gear. For example, when measuring AC mains power, the measurement gear is placed in the electrical block. In this case, once the test leads contact the mains power, the multimeter can be damaged immediately. Internal components are damage. Therefore, before using a multimeter to measure, be sure to check whether the measurement เกียร์ คือ ถูกต้อง หลัง ใช้ % 2c set the การวัด การเลือก ถึง AC 750V หรือ DC 1000V% 2c ดังนั้น ที่ ไม่ เรื่อง อะไร พารามิเตอร์ เป็น วัดผิด ระหว่าง ถัดไป การวัด% 2c the ดิจิตอล มัลติมิเตอร์ จะ ไม่ เป็น เสียหาย
2. Some digital multimeters are damaged because the measured voltage and current exceed the measurement range. For example, measuring the mains power at the AC 20V range can easily cause damage to the AC amplifier circuit of the digital multimeter, causing the multimeter to lose its AC measurement function. When measuring DC voltage, if the measured voltage exceeds the measurement range, it is also easy to cause circuit failure in the meter. When measuring current, if the actual current value exceeds the range, it will generally only cause the fuse in the multimeter to blow out and will not cause other damage. Therefore, when measuring voltage parameters, if you do not know the approximate range of the measured voltage, you should first set the measurement gear, measure the value and then change gears to obtain a more accurate value. If the voltage value to be measured is far beyond the maximum range that the multimeter can measure, an additional high-resistance measuring pen should be used. Such as detecting the anode high voltage and focusing high voltage of black and white color TV sets.
3. The upper limit range of DC voltage of most digital multimeters is 1000V. Therefore, when measuring DC voltage, the maxum voltage value is below 1000V, which generally does not damage the multimeter. If it exceeds 1000V, the multimeter is likely to be damaged. However, different digital multimeters may have different upper limits of measurable voltage. If the measured voltage exceeds the range, a resistance step-down method can be used to measure it. In addition% 2c เมื่อ การวัด a DC สูง แรงดันไฟฟ้า ของ 40O % 7e 1000V% 2c the test leads must be in good contact with the measurement point without any jitter. Otherwise% 2c in addition to causing damage to the multimeter and making the measurement inaccurate% 2c in serious cases% 2c the multimeter may not have any show
4. เมื่อ วัด ความต้านทาน, be ระวัง ไม่ ถึง วัด ในขณะที่ มัน คือ สด
