Quality of measurements on the graduated scales

Quality of single measurement

Uncertainty of the amendment. Uncertainty of value of the measured size. Indicators of quality of single measurement - accuracy and correctness.

Quality of repeated measurement

Uncertainty of counting. Uncertainty of the indication. Uncertainty of the amendment. Uncertainty of value of the measured size. Indicators of quality of repeated measurement - accuracy and correctness - at ravnotochny and neravnotochny values of counting.

the raduirovka of measuring instruments (German graduiren — to graduate, lat. gradus — a step, a step, degree) — metrological operation by means of which a gage (a measure or the measuring device) supply with a scale or the calibration table (curve). Marks of a scale should to correspond with demanded accuracy to values of the measured size, and the table (curve) with demanded accuracy to reflect effect communication in a device exit with the size brought to an entrance (for example, dependence of EDS of the thermocouple of a pyrometer on temperature of her worker spy).

 

Graduation is made by means of more exact, than graduated, measuring instruments according to which indications establish the valid values of the measured size. Exact measuring instruments are graduated individually, less exact are supplied with the standard scale printed in advance, or the standard table (curve) graduation. Application of standard scales or the standard graduated tables demands sometimes adjustment of measuring instruments for the purpose of finishing of their errors to established by norms.

 

Metrological control of technical documentation. Organization and procedure. Metrological control design documentation. Metrological control process documentation. Documenting the results of monitoring. Duties and rights of persons conducting metrological control.

Obtaining measuring information is connected with definition of a delay of distribution of probing impulses. The momentum transfer in the form of the packages filled with fluctuations of bearing frequency, gives a power prize and provides a high noise stability and an informativnost of the measuring channel.

Obtaining necessary measuring information with minimum (or limited) material and temporary inputs demands an attentive approach to preparation and carrying out experiment at measurement of physical sizes. It gains the special importance at statement of difficult expensive experiments. In understanding of a place of measuring experiment that circumstance is important that measurements carry out not for the sake of measurements, and for achievement of the purpose put in this or that research or test. In this regard by preparation of measuring experiment the question first of all is solved: for what to measure. The solution of this question makes essential impact on all procedure of measurement including preparation, carrying out and processing of results of measurements. Depending on the purpose of measurement such problems as what to measure are solved, with what accuracy to measure how to measure and than to measure. Answers to these questions define the content of preparation of experiment at measurement of physical sizes.

Obtaining exact and full measuring information on behavior of object of regulation is most complicated at management of indicators of structure and properties of substances., As a rule, it is impossible to measure parameter interesting us in these cases directly and indirect measurements are used. So, for determination of concentration of solution measure its density and use known dependence of concentration on solution density. If solution multicomponent, for determination of concentration of separate components it is necessary to measure except solution density additional parameters, such, as an elektroprovodnost and viscosity. Accuracy of such indirect measurements can appear insufficient for the purposes of management of technological process.

For obtaining measuring information from many objects or about a large number of parameters of some object, and in some cases and for processing of this information, the special measuring devices which have received the name of information and measuring systems are created. They represent set of measuring instruments, cybernetic and auxiliary devices.

On a way of obtaining measuring information deep devices are subdivided two groups: 1) independent, which results of measurement can be received only after extraction them from a well, IT 2) remote, providing a signal transmission of measuring information on a cable on an earth surface.

On a way of obtaining measuring information the deep - Ttrybora are subdivided into two groups: 1) independent, which results of measurement can be received only after extraction them from a well, and 2) remote, providing a signal transmission of measuring information on a cable on an earth surface.

In some cases obtaining measuring information on controllable process is connected with need of performance of arithmetic operations with frequencies of compared signals. More often measuring information contains in the sum, a difference or the relation of frequencies of target signals of sensors.

The measuring system provides obtaining complex measuring information on properties of breeds directly on a face, its transfer for registration in an analog or discrete form. Continuous record of the signals arriving from primary converters of a probe (in scales 1: 50 and 1: 100 on depth), it is provided with the corresponding ratios of speeds of a protyazhka of a tape of a recorder and probe movement in soil.

Scanning IS are intended for obtaining measuring information on a condition of a field of physical sizes.

Existing practice provides generally obtaining measuring information in field and trade conditions, and its processing - in stationary geophysical laboratories.

The choice of this or that way of obtaining measuring information essentially depends on the nomenclature of measured parameters, dynamic properties of controllable parameter, reliability (non-failure operation and maintainability) analyzers and their metoologichesky providing.

Striking example of modern possibilities of telemeasurements is obtaining measuring information from spaceships when, besides measurement of parameters of the ship, the physiological condition of cosmonauts with transfer of these data to Earth is supervised.

As all gages are intended for obtaining measuring information, it is necessary to stop especially on their information characteristics.

For obtaining measuring information, and also the scientific questions arising thus, the branch of science and the technicians, called by measuring equipment is engaged in production and application of measuring instruments. Thus, the measuring equipment is considered as the sphere of activity of people including scientific activity, production and operation of measuring instruments. The part of scientific bases of measuring equipment is made by metrology as a science about measurements, methods and means of ensuring of their unity and ways of achievement of demanded accuracy.

Definition of the main error pursues the purpose obtaining objective measuring information on real metrological characteristics calibrated in the SI and is one of the main operations by results of which carrying out suitability of SI to further operation is defined.

Let's allocate basic elements of systems without which obtaining measuring information is impossible, and on this element basis we will define possible structures of IS.

In brought to attention of the reader to the book theoretical bases of obtaining measuring information unite with their annex to an explanation of principles of action and design of the IIS main versions.

Showing devices of control of pressure apply to measurement of pressure and obtaining measuring information in a manometer or tyagonaporomer installation site. During the studying and the analysis of technical documentation it is necessary to pay attention to that the working pressure specified in the specification did not exceed 0 75 top limits of measurements of a manometer at relative stability of measured pressure and 0 66th scales of the device at pulsing or sharply changing at operation of the unit pressure.

Showing devices of control of pressure apply to measurement of pressure and obtaining measuring information in a manometer or tyagonaporomer installation site. During the studying and the analysis of technical documentation it is necessary to pay attention to that the working division specified in the specification did not exceed 0 75 top limits of measurements of a manometer at relative stability of measured pressure and 0 66th scales of the device at pulsing or sharply changing at operation of the unit pressure.

For determination of METs parameters the decision of system of the equations that demands obtaining measuring information on active or passive sizes is necessary.

Development of means of IIT is connected with reduction of the power expenses necessary for obtaining of measuring information. So, In electric equipment transition from devices with manual, management to electromechanical automatic devices, and then to the devices based on application of electronic, полупроводниковых1и of microminiature elements, was steadily connected with reduction of the energy spent for performance of process of measurement. This way of improvement of one of operational external characteristics of means of IIT depends mainly on the element base used for нх of construction.

The set of measured parameters, their spatial dispersal, need of automation of management by centralized obtaining measuring information, its processing and elaboration of operating influences predetermine primary use of electric methods of measurement of not electric sizes as electric signals are most convenient for transfer, measurement and processing.

The dosimeter - the device or installation for measurement of ionizing radiation - is intended for obtaining measuring information on an exposition dose and capacity of an exposition dose of photon radiation and (or) about the energy transferred by ionizing radiation or transferred to object, being in a radiation action field.

Radiometr - the device or installation for measurement of the ionizing radiation, intended for obtaining measuring information on activity of a radio nuclide in a source or the sample derivative of it of sizes, about density of a stream and (or) a stream and флюенсе (transfer) of ionizing particles.

The dosimeter - the device or installation for measurement of ionizing radiation - is intended for obtaining measuring information on an exposition dose and capacity of an exposition dose of photon radiation and (or) about the energy transferred by ionizing radiation or transferred to object, being in a radiation action field.

Radiometr - the device or installation for measurement of the ionizing radiation, intended for obtaining measuring information on activity of a radio nuclide in a source or the sample derivative of it of sizes, about density of a stream and (or) a stream and флюенсе (transfer) of ionizing particles.

Lack of test methods and methods of exemplary measures is that additional measurements of tests or exemplary measures are necessary for obtaining additional measuring information. More often additional measurements are carried out consistently in time that reduces speed of IIS as a whole. At fast change of the measured size it can lead to loss of considerable volumes of necessary measuring information.

Nevertheless there are also essential peculiar features without which obtaining qualitative measuring information on a chemical composition is impossible.

The system can be used as independently, and as a part of АСУТП, providing obtaining measuring information, its transformation and representation in a demanded look to the consumer - to the operator who has been directly connected with performance of technological operations, and for input in АСУТП.

In these (5.92) characteristics are designated uniformly: equality to zero of any physical characteristic excludes possibility of obtaining measuring information.

 








Дата добавления: 2015-12-26; просмотров: 641;


Поиск по сайту:

При помощи поиска вы сможете найти нужную вам информацию.

Поделитесь с друзьями:

Если вам перенёс пользу информационный материал, или помог в учебе – поделитесь этим сайтом с друзьями и знакомыми.
helpiks.org - Хелпикс.Орг - 2014-2024 год. Материал сайта представляется для ознакомительного и учебного использования. | Поддержка
Генерация страницы за: 0.013 сек.