Multimeter, divided into digital multimeter and pointer multimeter, is an indispensable measuring instrument in power electronics and other departments. It is generally used to measure voltage, current and resistance as the main purpose. Whether digital or traditional, they both play an important role in measurement, but what are the advantages and disadvantages of the two?
Pointer multimeter:
1. The pointer multimeter is an average value meter, which has an intuitive and vivid reading indication.
2. The pointer multimeter generally has no internal amplifier, so the internal resistance is small.
3. Due to the small internal resistance of the pointer multimeter and the use of discrete components to form a shunt and voltage divider circuit, the frequency characteristics are uneven.
4. The internal structure of the pointer multimeter is simple, so the cost is lower, the function is less, the maintenance is simple, and the overcurrent and overvoltage capability is strong.
5. The output voltage and current of the pointer-type multimeter are high, which can easily test thyristors, light-emitting diodes, etc.
Digital Multimeter:
1. The digital multimeter is an instantaneous type instrument. It takes a sample every 0.3 seconds to display the measurement results, and the reading results are not as convenient as the pointer type.
2. The internal resistance of the digital multimeter can be made large due to the internal use of an operational amplifier circuit, which makes the impact on the circuit under test smaller and the measurement accuracy is higher.
3. The digital multimeter adopts a variety of oscillation amplification, frequency division, protection and other circuits, so it has many functions.
4. Because the internal structure of the digital multimeter uses integrated circuits, the overload capacity is poor, and it is generally difficult to repair after damage.
5. The output voltage of the digital multimeter is low (usually no more than 1 volt), which is inconvenient for the testing of some components with special voltage characteristics, such as thyristors, light-emitting diodes, etc.
Therefore, through the above comparison, we know the advantages and disadvantages of digital multimeters and traditional multimeters. Therefore, in order to better eat the multimeter, the editor recommends that for beginners, an analog multimeter should be used. , which can help new scholars better read the data and become familiar with the usage.
