According to the class classification, measuring instruments can be divided into the following three categories
1, the scope of Class A measuring instruments:
The company's highest standard of measurement and measurement of standardized instruments; used for trade settlements, safety and security, medical and health care and environmental monitoring, and included in the scope of mandatory verification work measuring instruments; Production process and quality testing in the process of key parameters with measuring instruments; in and out of the plant material accounting with measuring instruments; precision testing in the high accuracy or frequent use of measuring instruments and poor reliability of the value.
Type A measuring instruments, including: a flat crystal, zero-level cutter ruler, level gauge gauge, right-angle ruler gauge, measuring tape gauge, percent gauge gauge, micrometer gauge, self-collimator, vertical optical meter.
2, the scope of Class B measuring instruments:
Safety, health care and environmental monitoring, but is not included in the mandatory verification of the scope of measuring instruments; production process is not a key parameter of the measuring instruments; product quality of the general parameters of the detection of measuring instruments; two or three energy measurement measuring instruments; measuring instruments for material management within the enterprise.
Type B measuring instruments include: calipers, micrometers, measuring tape, micrometers, levels, rulers, plug gauges, levels, latitude and longitude, welding inspection tape, ultrasonic thickness gauge, more than 5M tape measure.
And thermometers, pressure gauges, force gauges, tachometers, scales, hardness testers, balances, voltmeters, ammeters, megohmmeters, electric power meters, bridges, resistance boxes, current detectors, multimeters, standard resistance boxes, calibration signal generators, ultrasonic flaw detectors, spectrophotometers, etc..
3, the scope of C measuring instruments:
Low-value consumable, non-compulsory calibration of measuring instruments; the company's living area of the internal energy distribution of measuring instruments, auxiliary production measuring instruments; in the use of measuring data in the process of measurement of the measurement of imprecise requirements of the instruments; the national measurement of the administrative department expressly allows a one-time calibration of the measuring instruments.
Category C includes steel straightedge, curved ruler, steel tape measure below 5M, etc..
Structural features
Categorized by structural features, measuring instruments can be divided into the following three categories:
Gauge is that the fixed form of reproducing the value of measuring instruments, such as blocks, weights, standard batteries, standard resistors, bamboo and wood ruler. Line ruler, etc.;
Measuring instruments. Measuring instruments that will be measured into directly observable indicator value equivalent information, such as pressure gauges, flow meters, thermometers, ammeters, voltmeters. Electrocardiograph, etc.;
Measurement device. That is, in order to determine the measured value must be the overall combination of measuring instruments and auxiliary equipment, such as mileage meter calibration device, high-frequency microwave power meter calibration device.