3. Key questions

3.1. Explain the term "certification".

3.2. Name the components of the certification process.

3.3. What is a certification system?

3.4. What technical instruments are referred to MI?

3.5. Explain the concept of NMC.

3.6. What is a hysteretic of the indicators?

3.7. What is an accuracy class?

3.8. Why accuracy class does not uniquely determine the accuracy of the measurement?

3.9. What is the metrological certification?

3.10. What is characterized the structure of the error at each point of the scale by?

3.11. How do the systematic and random components of the MI error find themselves and in what conditions?

3.12. What are sources of systematic and random components of errors of the testing generator, in your opinion? Give the examples.

3.13 In which cases are carried out single measurements, and in which - multiple?

3.14. What numerical characteristics is described the probability density by? Give the examples of the probability density and its numerical characteristics.

3.15. What reason can cause hysteretic in the device with dial indicator?

3.16. Which is a character of development of hysteretic: random or systematic?

4. Home task

4.1. Study the section [1] “Estimation of conformity” using textbook.

4.2. Learn from a textbook section [2] "Errors and mathematical processing of measurements’ results."

4.3. Write down the procedure using section 2.4.5 for the case, when it is known before test that the hysteresis is absent in tested MI.

4.4. Design a plan of work in the laboratory (the measurement scheme, tables).

4.5. Be prepared to discuss the key questions of section 3.

5. Laboratory task

5.1. Get acquaintance with the workplace equipment: make external review (you must determine the absence of mechanical damages, the presence of control regulators).

5.2. Learn the basic NMC of MI that are certificated and write down a list of them in the table 1:

Table 1 - Main NMC of MI

Title of characteristics	NMC, allowable standard

5.3. Confirm with a teacher plan of work.

5.4. Write down the technical characteristics of equipment (as a table, which must include: title, types of devices; NMC, their basic parameters).

5.5. Connect to the tested device model device and test it for compliance with NMC according to section 2.4.5.

Digitized point on the scale of the testing device should be agreed with a teacher.

5.6. Test results of device must be noted in the table 2.

Table 2 – Test and calculation results

№	1	2	3	4	5	6	7	8	9	10