Can a pointer multimeter measure AC current
There are two ways to split: first split and then rectify, or first rectify and then split.
1. The difference in the order of rectification and shunt
When using the method of first diverting and then rectifying, the current flowing through the rectifying element is relatively small; However, rectifying first and then diverting means that all the measured current passes through the rectifier element, which limits the range of the AC ammeter to the allowable current of the rectifier element. Therefore, this method is less commonly used.
2. Common Rectification AC Ammeter Circuit
The voltage at both ends of the circuit will vary with the range, and due to the presence of a rectifier element, the internal resistance in the AC ammeter increases, which is a disadvantage of the resistance divider circuit.
The multimeter can still work after removing the glass safety tube
In a typical digital multimeter, there are two fuse tubes, one is around 500mA, and the other is around 10A. The two fuses are connected in series at different current levels. Once the fuse is burned out, the corresponding current level will definitely be unusable, while the voltage and resistance levels can still be used normally.
Friends who are engaged in circuit maintenance work are definitely very familiar with multimeters. I believe everyone has experienced selecting the wrong range or inserting the wrong hole to some extent. Generally, the fuse is burnt out. When we encounter this situation, it is best not to replace it randomly, but to choose the fuse based on the fusing current and internal resistance. It is best to replace the original fuse, otherwise it will cause the fusing time to be too slow, Not functioning as a normal insurance, once the wrong range is selected, it is likely to cause permanent damage to the multimeter.
