In the test and measurement, the majority of engineers will use a variety of electronic measuring instruments, for different measurement requirements, choose different measuring instruments, then, in the specific use process, the instrument error is an unavoidable problem. Today, let’s have a detailed understanding of the causes of errors in electronic measuring instruments? Let’s have a look!
Error analysis of electronic measuring instrument
In practical engineering application, the error caused by measuring tools is inevitable. Comprehensive analysis shows that the analysis of errors mainly includes the following aspects:
First, the measurement method is not correct.
Second, there is no correction or deviation of the measuring equipment.
Third, the surveyors are not proficient in operation.
Fourth, there are interference sources in the measurement process.
Some of these errors are caused by the measurement system, and some are caused by accidental factors. The following is a brief introduction to the causes of errors.
Instrument error 1
The mechanical performance or electrical structure of the instrument itself is not perfect, which often leads to the error of the instrument itself. For example, before using the instrument, there is no correction, because some instruments are not used for a long time, the zero point will shift, the division of the scale is not clear, etc. The way to eliminate these errors is to correct them before use. Secondly, we can also avoid it by replacing some equipment and averaging multiple measurements of the same test.
2. Instrument use error
Use error is caused by improper operation of the tester in the process of use. During the installation, the instrument should be placed, adjusted or installed in accordance with the instrument specifications. Improper operation will result in the deviation of measurement direction. For example, the spectrophotometer should be preheated for half an hour before use. If it is not preheated, it may lead to the formation of error. The way to avoid or reduce this error is to consult the experienced users; read the operation manual and working principle drawing of the instrument carefully, make clear the model and structure of the instrument, and then use it after knowing the operation method in detail.
3 human error of instrument
Human error is usually caused by the surveyor himself. This kind of error can often be avoided, most of which are caused by the operator’s carelessness or improper operation. When not in the right direction, for example, when not in the right position. In order to avoid this kind of error, it is necessary to train the surveyors in advance, improve their measurement quality and sense of responsibility, and enhance the accuracy of measurement results.
4 instrument environment error
The influence of environment on the measurement results is very obvious, especially for some high-precision instruments. The external environment usually includes temperature, humidity, electric field, magnetic field, electromagnetic wave and so on. Different measuring instruments have different sensitive factors. For example, in the process of using some measuring instruments, it is necessary to ensure that the environment is in a relatively dry environment, and the environmental humidity is too large or the fluctuation will have a greater impact on the measurement results. For example, when the ultrasonic flowmeter is installed and used, if there is a serious acoustic interference outside the measurement site, it is very likely to have an impact on the measurement results, and even lead to the measurement failure conduct. Therefore, we should read the manual carefully first, and try to avoid the error caused by the interference of external conditions.
5 theoretical error of instrument
The theoretical error is that the instrument is designed according to the simplified approximate formula in theory. This kind of unscientific instrument itself has some errors. Even if it is operated according to the above four items, the result is not correct. The way to correct the error is to strengthen the theoretical study of the instrument and design the instrument with more scientific and rigorous theory.
The methods to solve the error include the guiding scheme of principle and the specific adjustment method. Specifically, the system error can be reduced by selecting the appropriate instrument, and the more accurate measurement and calculation method can be selected to reduce the error caused by human factors. Only through appropriate means to avoid or reduce the error, can the instrument and equipment be in a stable working state for a long time, and the measurement results can be more accurate and more in line with our use requirements.
Editor in charge: GT