1- laboratory work determination of errors of measuring instrument the Purpose of the work

1- LABORATORY WORK
DETERMINATION OF ERRORS OF MEASURING INSTRUMENTS1. The Purpose of the work.
To study the principle and theory of operation of measuring instruments in magnetoelectric, electromagnetic, electrodynamic systems and to determine the errors of voltmeters in this system.
Theoretical part
Measurement errors can appear in different ways for a variety of reasons. These reasons include:
- the reasons for adjusting or shifting the level of adjustment when using the measuring instrument;
- Reasons for placing the measuring object in the measuring position;
- Reasons for obtaining, storing, modifying and recommending measurement data in the chain of measuring instruments;
- causes of external influences on the measuring instrument and object (changes in temperature or pressure, the effect of electric and magnetic fields, various vibrations, etc.);
- causes arising from the characteristics of the object of measurement;
- reasons related to the qualifications and status of the operator, etc.
When analyzing the causes of measurement errors, it is first necessary to identify the factors that significantly affect the measurement results.
Measurement errors are divided into the following types according to their characteristics:
I. Depending on the expression of measurement errors are divided into the following types:

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  Absolute error. This error is expressed in units of magnitude. For example, 0,2 V; 1,5 m etc. The absolute error is determined as follows:
  

here, А_x – measurement result;
А_true – the true value of magnitude;
А_о – the actual value of the magnitude.
The absolute error taken with the inverse sign is called the correction and is denoted by δ.
- = δ or А_о=А_X+ δ.

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