What factors affect the measurement accuracy of DC meters?- Zhejiang Yongtailong Electronic Co., Ltd

There are many factors that affect the measurement accuracy of DC meters, mainly including the following aspects:
1. Manufacturing process and error of the instrument itself
Manufacturing process: The manufacturing process of the DC meter determines its internal accuracy and stability. If there are defects or deficiencies in the manufacturing process, it will directly affect the measurement accuracy of the voltmeter.
Internal components: The accuracy and stability of the resistors, capacitors, inductors and other components inside the meter will also affect the measurement results.

2. Usage method
Voltmeter placement: The voltmeter should be placed flat and not tilted. Because the needle itself has gravity, tilting will increase the error.
Needle zeroing: Before use, make sure that the needle of the voltmeter has been zeroed to avoid measurement errors caused by the needle not being zeroed.
Gear selection: The measured voltage range should be as close as possible to the voltage of the voltmeter gear. For example, low voltage cannot be measured with a high gear, which will result in inaccurate readings and increased errors in the voltmeter itself.

3. Measurement environment
Magnetic field interference: DC voltmeters should avoid interference from strong magnetic fields during measurement. Because the magnetic field will affect the working state of the internal components of the voltmeter, thereby affecting the measurement accuracy.
Temperature influence: Temperature changes may also affect the measurement accuracy of the voltmeter. In high or low temperature environments, the performance of the internal components of the meter may change, resulting in increased measurement errors.
Humidity and air pressure: Although these factors have relatively little effect on DC voltmeters, their impact on measurement accuracy should still be noted in extreme environments.

4. Characteristics of the measurement signal
Waveform quality: If the AC component in the DC power supply is not fully filtered out, or the DC voltage waveform itself is distorted, errors will occur when using a DC voltmeter for measurement.
Ripple and harmonics: In applications such as DC charging piles, the DC output signal may contain ripple and high-frequency harmonics, and the presence of these signals will also affect the measurement accuracy of the DC voltmeter.

5. Other factors
Power supply stability: The stability of the power supply during the measurement process also has an important impact on the measurement accuracy. If the power supply fluctuates greatly, it will directly affect the measurement results of the voltmeter.
Human factors: The skill level and operating habits of the operator may also affect the measurement accuracy. For example, the line of sight angle and reading speed during reading may affect the accuracy of the measurement results.