SI verification -verification of measuring instruments- a set of operations performed in order to confirm the compliance of measuring instruments with metrological requirements.

Measuring instruments intended for use in the field of state regulation of ensuring the uniformity of measurements, before commissioning, as well as after repair, are subject to primary verification, and during operation - periodic verification. Using measuring instruments in the field of state regulation of ensuring the uniformity of measurements legal entities and individual entrepreneurs are obliged to submit these measuring instruments for verification in a timely manner.

Verification of measuring instruments is carried out by legal entities and individual entrepreneurs accredited in accordance with the established procedure in the field of ensuring the uniformity of measurements.

Government Russian Federation a list of measuring instruments is established, the verification of which is carried out only by state regional centers of metrology accredited in the prescribed manner in the field of ensuring the uniformity of measurements.

Verification results measuring instruments are certified with a verification mark and (or) verification certificate. The design of the measuring instrument must ensure the possibility of applying the verification mark in a place accessible for viewing. If the design features or operating conditions of the measuring instrument do not allow applying the verification mark directly to the measuring instrument, it is applied to the verification certificate.

Verification procedure measuring instruments, the requirements for the verification mark and the content of the verification certificate are established by the federal executive body, which carries out the functions of developing state policy and legal regulation in the field of ensuring the uniformity of measurements.

Information about the verification results measuring instruments intended for use in the field of state regulation of ensuring the uniformity of measurements are transferred to the Federal Information Fund for ensuring the uniformity of measurements by legal entities and individual entrepreneurs conducting verification of measuring instruments.

Measuring instruments that are not intended for use in the field of state regulation of ensuring the uniformity of measurements may be subjected to verification on a voluntary basis.

Requirements for the organization and procedure for verification of measuring instruments are established by the metrology rules PR 50.2.006-99 “GSI. Procedure for verification of measuring instruments”.

Measuring instruments subject to state metrological control and supervision are subject to verification upon release from production or repair, upon import and operation. Specific lists of measuring instruments to be verified are made up by legal entities and individuals - owners of measuring instruments. These lists are sent to the HMS bodies, which, in the process of implementing the HMN, monitor the correctness of compiling lists of measuring instruments subject to verification in compliance with metrological rules and norms. Methodological materials for compiling lists of measuring instruments, as well as comments on the areas of use of measuring instruments that are subject to verification, are set out in the recommendation MI 2273-93 “GSI. Areas of use of measuring instruments subject to verification”.

The bodies of the State Migration Service carry out verification of measuring instruments on the basis of verification schedules drawn up by legal entities and individuals. Verification schedules are drawn up according to the types of measurements in the prescribed form and sent (in 3 copies) to the State Migration Service. Within 10 days from the date of receipt, the HMS body reviews and agrees on the schedules for MI verification. The first copy of the verification schedules agreed upon and signed by the head of the HMS body is sent to the applicant.

By decision of the State Standard, the right to verify SI can be granted to metrological services (MS) of legal entities, regardless of their industry affiliation and form of ownership. The requirements for MS of legal entities accredited for the right to verify measuring instruments and the procedure for their accreditation are established by the rules of PR 50.2.014-96 “GSI. Rules for the Accreditation of Metrological Services of Legal Entities for the Right to Verify Measuring Instruments”. Recommendations on the construction and content of MS documents accredited for the right to verify measuring instruments are given in MI 2284-94 “GSI. Documents of calibration laboratories.

Verification activities carried out by legal entities accredited by the MS are controlled by the SMS bodies at the location of these legal entities.

Verification of MI is carried out by an individual certified as a verifier in accordance with the rules of PR 50.2.012-94 “GSI. The procedure for attestation of verification officers of measuring instruments.

Verification is carried out in accordance with the normative documents approved based on the results of MI tests.

The result of verification is confirmation of the suitability of the measuring instrument for use or its recognition as unsuitable for use.

If, based on the results of verification, the measuring instrument is recognized as suitable for use, then an impression of a verification mark is applied to it and (or) the technical documentation that meets the requirements of document PR 50.2.007-94 “GSI. Verification stamps”, and (or) a “Certificate of Verification” of the established form is issued.

If, based on the results of verification, the MI is found unsuitable for use, the impression of the verification mark and (or) the “Certificate of Verification” is canceled and a “Notice of Unsuitability” of the established form is issued or appropriate entries are made in the technical documentation.

MI are subject to primary, periodic, extraordinary, inspection and expert verification.

Primary verification are subject to SI upon release from production and repair, upon import by import. MI may not be subjected to primary verification when imported on the basis of agreements or agreements concluded by the State Standard of Russia on the recognition of the results of verification performed in foreign countries. As a rule, each copy of the measuring instrument is subject to primary verification, but selective verification is also allowed.

Periodic verification measuring instruments that are in operation or in storage are subject to a certain calibration interval. Each copy of the measuring instrument must undergo periodic verification.

Periodic verification SI intended for measuring (reproducing) several quantities or having several measurement ranges, but used for measuring (reproducing) a smaller number of quantities or on a smaller number of measurement ranges, it is allowed, based on the decision of the chief metrologist or the head of a legal entity, to produce only according to those requirements of regulatory documents for verification, which determine the suitability of the SI for the number of quantities used and the measurement ranges used. An appropriate entry must be made in operational documents.

First calibration interval is established upon approval of the MI type. HMS bodies and legal entities are required to keep records of the results of periodic verification and develop recommendations for adjusting calibration intervals. Adjustment of calibration intervals is carried out by the HMS body in agreement with the legal entity's MS.

Extraordinary verification is carried out during the operation (storage) of measuring instruments at:

1. damage to the sign of the verification mark, as well as in case of loss of the certificate of verification;
2. putting the MI into operation after long-term storage (more than one calibration interval);
3. carrying out re-adjustment or adjustment, known or expected shock effect on the measuring instrument or its unsatisfactory operation;
4. sale (sending) to the consumer of measuring instruments not sold after the expiration of a period equal to half of their calibration intervals;
5. the use of SI as components after a period equal to half of the calibration intervals.

Inspection verification produced to determine the suitability for the use of SI in the implementation of state metrological supervision. Such verification may not be carried out in full, provided for by the verification procedure. The results of the inspection verification are reflected in the inspection report. Inspection verification is carried out in the presence of a representative of the legal or natural person being checked.

GOST 8.513-84
(ST SEV 4829-84)

Group T80

STATE STANDARD OF THE UNION OF THE SSR

STATE SYSTEM FOR ENSURING THE UNIFORMITY OF MEASUREMENTS

VERIFICATION OF MEASURING INSTRUMENTS

Organization and procedure

State system for ensuring the uniformity of measurements.
Verification of measuring instruments. Organization and procedure

OKSTU 0008

Introduction date 1985-07-01

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the USSR State Committee for Standards

DEVELOPERS

M.A. Adadurov, Kh.O. Malikova, A.V. Plotnikova, V.A. Skovorodnikov, M.G. Sharonov (theme leader)

2. APPROVED AND INTRODUCED BY Decree State Committee USSR according to the standards of 10.24.84 No. 3640

3. INSTEAD OF GOST 8.002-71 in part of Sec. 3, 5

4. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

5. REPUBLICATION (October 1997) with Amendments No. 1, 2, approved in October 1985, September 1987 (IUS 1-86, 1-88)

This standard establishes the basic requirements for the organization and procedure for verification of measuring instruments manufactured and repaired, purchased by import, as well as in operation and storage.

The standard complies with ST SEV 4829-84 in terms of general provisions and the procedure for conducting primary verification (see Appendix).

1. GENERAL PROVISIONS

1. GENERAL PROVISIONS

1.1. Verification of measuring instruments is carried out to establish their suitability for use.

Measuring instruments are recognized as suitable for use during the calibration interval, the verification of which, carried out in accordance with the requirements of regulatory and technical documents for verification, confirms their compliance with the metrological and technical requirements for this measuring instrument, established in the regulatory and technical documents.

1.2. Measuring instruments are subjected to primary, periodic, extraordinary, inspection and expert verification.

1.3. Measuring instruments are subject to primary verification upon release from production or repair, as well as measuring instruments imported. Imported measuring instruments are not subject to primary verification in cases where the results of verification carried out in other countries are recognized by the State Standard in accordance with international agreements on mutual recognition of the results of state tests and verification.

Note. In justified cases, enterprises, organizations and institutions may establish in their technical documentation the relevant metrological and technical requirements for measuring instruments that are in operation and are not subject to mandatory state verification, based on the scope of these measuring instruments, as well as the criterion of their suitability for use.



1.4. Measuring instruments that are in operation or in storage are subject to periodic verification at certain inter-verification intervals established with the calculation of ensuring the suitability for use of measuring instruments for the period between verifications.

1.5. Extraordinary verification is carried out during operation (storage) of measuring instruments at:

the need to verify the suitability for the use of measuring instruments;

the use of measuring instruments as components after half of the calibration interval on them;

damage to the verification mark, seal or loss of a document confirming that the measuring instruments have passed primary or periodic verification, including during their storage;

commissioning of measuring instruments after storage, during which periodical verification could not be carried out due to the requirements for the conservation of measuring instruments or products containing measuring instruments;

re-preservation of measuring instruments, as well as products, in the set of which measuring instruments are used;

transfer of measuring instruments for long-term storage after half of the calibration interval for them;

sending to the consumer of measuring instruments not sold by the manufacturer after half of the calibration interval for them.

Note. It is recommended that an extraordinary verification be carried out before commissioning of measuring instruments taken from the warehouse after storage and transportation.

1.6. Inspection verification is carried out to determine the suitability for the use of measuring instruments in the implementation of state supervision and departmental control over the condition and use of measuring instruments.

1.7. Expert verification is carried out in case of disputes regarding metrological characteristics, serviceability of measuring instruments and their suitability for use.

1.8. Verification of measuring instruments is carried out by bodies of the state metrological service, headed by the State Standard, certified for the right to conduct state verification of measuring instruments, and enterprises, organizations and institutions (hereinafter referred to as enterprises) of other departmental affiliation, which have the right to verify in accordance with the procedure established by the State Standard.

1.9. Verification of measuring instruments is carried out by persons certified as state or departmental verification officers in the manner prescribed by the State Standard.

1.10. Verification of measuring instruments is carried out in accordance with the requirements of normative and technical documents for verification.

1.11. For the verification of measuring instruments carried out by the bodies of the state metrological service, fees are charged according to the rates approved by the State Standard in agreement with the Ministry of Finance.

1.12. For verification of measuring instruments carried out by enterprises for enterprises of the same or other departmental affiliation, payment is collected on the basis of agreements (letters of guarantee) concluded by them.

1.13. All costs associated with calling state verifiers are paid by the enterprises.

1.14. Measuring instruments used to monitor the change in quantities without assessing their values ​​in units of physical quantities with normalized accuracy are not subject to verification.

Control over the serviceability of such measuring instruments is carried out in the manner established by the enterprises.

The designation "I" must be applied to measuring instruments or in their operational documents.

1.15. Measuring instruments used for educational purposes are not subject to verification.

Control over the serviceability of measuring instruments used for educational purposes is carried out in the manner prescribed in the rules for their operation, and in accordance with the requirements of the educational process. Measuring instruments used for educational purposes must be marked "U".

1.16. Verification of measuring instruments that are the personal property of citizens is not mandatory and is carried out at their request.

2. ORGANIZATION AND PROCEDURE OF VERIFICATION

2.1. The following are subject to mandatory state verification:

measuring instruments belonging to the bodies of the state metrological service;

original exemplary measuring instruments of enterprises;

measuring instruments released from production as exemplary according to their intended purpose or under the terms of a manufacturing order;

measuring instruments intended for use and used as workers for measurements, the results of which are used to account for material values, fuel and energy, in mutual settlements, in trade, for protection natural environment, ensuring labor safety;

measuring instruments used for measurements, the results of which serve as the basis for the registration of national and international sports records.

2.2. Departmental verification is subject to measuring instruments that are not included in the list of measuring instruments subject to mandatory state verification (clause 2.1).

Notes:

1. In some cases, in agreement with the State Standard, verification by enterprises of the measuring instruments specified in clause 2.1 is allowed.

2. Measuring instruments used as workers for measurements, the results of which are used within the enterprise to account for material assets, fuel and energy and mutual settlements, are subject to departmental verification.

2.1, 2.2. (Revised edition, Rev. No. 2).

2.3. Departmental verification of measuring instruments is carried out by subdivisions of the metrological service of enterprises.

In justified cases, it is allowed to carry out departmental verification by other divisions of enterprises.

2.4. Measuring instruments, the verification of which cannot be provided by enterprises, are submitted for verification to the bodies of the state metrological service or to other enterprises of the same or other departmental affiliation, to which the right of verification is granted by the bodies of the state metrological service.

At the same time, enterprises or their higher organizations must submit to the bodies of the state metrological service, at their request, an action plan for organizing departmental verification of measuring instruments that are not provided with verification, or a rationale for the inexpediency of its organization.

2.5. Verification of measuring instruments can be carried out by the bodies of the state metrological service:

in stationary calibration laboratories;

in mobile calibration laboratories;

directly at the enterprises, by sending state verifiers to the enterprises;

at checkpoints of enterprises manufacturing and repairing measuring instruments;

in temporary offices.

The procedure for sending state verification officers, using mobile verification laboratories, opening temporary offices and organizations of control and verification points is established by the State Standard.

2.6. When carrying out state verification of measuring instruments at the places of their manufacture, repair or operation, enterprises must:

ensure, if necessary, the delivery of verification and auxiliary means belonging to the bodies of the state metrological service to the place of verification and back;

allocate premises and support staff necessary for verification;

ensure, if necessary, the storage of exemplary measuring instruments belonging to the bodies of the state metrological service, under their seal;

provide, in the case of servicing the enterprise by a mobile calibration laboratory, a parking place and ensure its connection to the networks of electricity, gas and water supply, sewerage, as well as ensure its safety.

2.7. Enterprises releasing from production or repair, as well as operating measuring instruments, for the state verification of which stationary verification installations and stationary exemplary measuring instruments are required at the places of manufacture, repair or operation, must have appropriate installations and exemplary measuring instruments and provide them to the state authorities. metrological service.

2.8. Primary verification

2.8.1. Each copy of measuring instruments is subject to primary verification.

In some cases, provided for in the regulatory and technical documents according to clause 1.10 of this standard, it is allowed to carry out selective verification. For selective verification, one should also be guided by the requirements of GOST 18242 and GOST 20736.

(Revised edition, Rev. No. 1).

2.8.2. Initial verification is carried out:

at the place of manufacture of measuring instruments;

at the place of application of measuring instruments;

partly at the place of manufacture and partly at the place of use of measuring instruments.

The place of verification is established by the bodies of the state metrological service.

2.8.3. The state primary verification is carried out by the bodies of the state metrological service at the checkpoints (checkpoints) of instrument-making and instrument-repair enterprises.

Note. If the daily release of measuring instruments does not provide a constant load of one working verification, the verification procedure should be established in agreement with the body of the state metrological service.

2.8.4. For the state primary verification, measuring instruments released from production or repair should be presented after their acceptance by the technical control department.

Note. When carrying out repairs of measuring instruments outside the repair facility, mobile teams may present the measuring instruments for state verification by the person who carried out the repair, without prior acceptance by the technical control department.

2.9. Periodic verification

2.9.1. Calibration intervals for periodic verification are set by:

for measuring instruments subject to mandatory state verification - bodies of the state metrological service;

for measuring instruments subject to departmental verification - heads of enterprises.

2.9.2. Measuring instruments that are in long-term storage under conditions that ensure their suitability for use may not be subjected to periodic verification.

2.9.3. The state periodic verification is carried out within the calendar terms established by the verification schedules for exemplary and working measuring instruments.

The procedure for compiling and coordinating schedules for state verification of measuring instruments is established by the State Standard.

2.9.4. Verification of measuring instruments must be ensured by the bodies of the state metrological service without fail (within the terms agreed with the bodies of the state metrological service).

In the absence of the conditions necessary for the verification, the head of the body of the state metrological service is obliged to indicate another nearest body of the state metrological service or an enterprise capable of performing verification.

2.9.5. Measuring instruments must be submitted for state verification at the request of the state metrological service body, reactivated, together with a technical description, operating instructions, a passport or certificate of the last verification, as well as the necessary accessories.

2.9.6. The time spent by measuring instruments submitted for state verification in stationary verification laboratories, provided that they are submitted in accordance with the state verification schedule, should not exceed 15 days (with the exception of measuring instruments for which the verification norm exceeds this period).

2.9.7. The procedure for conducting departmental verification of measuring instruments is established by the head of the enterprise.

Note. Departmental verification is recommended to be carried out in accordance with the schedule.

(Revised edition, Rev. No. 2).

2.9.8. Periodic verification of measuring instruments intended for measuring (reproducing) several physical quantities or having several measurement ranges, but used constantly for measuring (reproducing) a smaller number of physical quantities or on a smaller number of measurement ranges, is allowed, based on the decision of the chief metrologist of the enterprise, to be carried out only for those the requirements of regulatory and technical documents for verification, which determine the suitability of measuring instruments for the applied number of physical quantities and the applied measurement ranges.

In these cases, the measuring instruments must be marked with a distinct inscription or symbols that determine the scope of their application. An appropriate entry must be made in operational documents.

2.9.9. In case of complex verification of measuring instruments (for example, verification of measuring systems) subject to departmental verification, when verification can be performed by the departmental metrological service only to a limited extent (not according to all the requirements of regulatory and technical documents for verification), it is allowed, with the consent of the state metrological service , carry out verification in full consistently by the departmental and state service with registration of its results by the state metrological service.

Note. When carrying out verification by the bodies of the state metrological service in accordance with paragraphs. 2.9.8 and 2.9.9 the amount of state fees for the verification of measuring instruments should be established based on actual labor costs.

2.10. Inspection verification

2.10.1. Inspection verification may not be carried out in full, provided for by regulatory and technical documents for verification.

2.10.2. The results of the inspection verification are reflected in the act of checking the condition and use of measuring instruments.

2.10.3. State inspection verification is carried out in the presence of representatives of the audited enterprise.

2.11. Expert verification

2.11.1. Expert verification is carried out by the bodies of the state metrological service at the written request (application) of the court, the prosecutor's office, the police, state arbitration, people's control bodies, at the written request of enterprises in case of disputes regarding metrological characteristics, serviceability of measuring instruments and suitability of measuring instruments for use and correctness operation of measuring instruments. The application must indicate the subject, purpose of expert verification and the reason that caused its need.

2.11.2. When carrying out expert verification of measuring instruments, if necessary, applicants, as well as representatives of the interested party, may be present.

2.11.3. Based on the results of the expert verification, a conclusion is drawn up, which is approved by the head of the state metrological service body, and sent to the applicant. One copy of the conclusion must be kept in the body of the state metrological service that carried out the expert verification.

Note. During expert verification, carried out at the request of the investigative and judicial authorities, the conclusion is drawn up in accordance with the requirements of these authorities.

APPENDIX (reference). INFORMATION DATA ON COMPLIANCE WITH GOST 8.513-84 ST SEV 4829-84

APPENDIX

Reference

Section 1 of GOST 8.513-84 corresponds to section 1 of ST SEV 4829-84.

Section 2 of GOST 8.513-84 corresponds to section 2 of ST SEV 4829-84.

(Introduced additionally, Amendment No. 1).



The text of the document is verified by:
official publication
M.: IPK Standards Publishing House, 1997

GOST 8.513-84 State system for ensuring the uniformity of measurements (SSI). Verification of measuring instruments. Organization and procedure (with Amendments No. 1, 2)

GOST 8.513-84 State system for ensuring the uniformity of measurements (SSI). Verification of measuring instruments. Organization and procedure (with Amendments No. 1, 2)

Primary, periodic, extraordinary, inspection and expert verification.

Depending on the goals and purpose of the verification results, there are primary, periodic, extraordinary, inspection and expert verification of SI.

Primary verification is carried out when measuring instruments are released from production or repair, as well as when importing measuring instruments that have passed state acceptance tests according to STB 8001-93. Imported measuring instruments are not subject to primary verification in the case when the results of verification carried out in other countries are recognized by the State Standard of the Republic of Belarus in accordance with international agreements on mutual recognition of test and verification results. Selective primary verification of SI is allowed.

Periodic verification of MI is carried out at intervals between calibrations, established taking into account the suitability of MI for use in the period between verifications in accordance with MI 2187-92. This verification is carried out during the operation and storage of MI according to the verification schedule.

Verification intervals are established during state acceptance tests or metrological certification of measuring instruments, based on reliability indicators. They must guarantee the metrological serviceability of the MI in the period between verifications. Annual calendar schedules for periodic verification are approved by the management of the enterprise. Schedules are compiled separately for measuring instruments submitted for verification to the State Metrological Service and the metrological service of business entities.

Measuring instruments that are in storage for a period exceeding the calibration interval are not subject to periodic verification, provided that the regulatory requirements for their preservation, storage conditions, type of preservation and packaging are met, such measuring instruments are verified before operation.

In metrological practice, there are signaling means (indicators) that do not belong to SI and are not verified. The right to transfer SI to the category of indicators is granted to the metrological services of business entities. According to the ND, the designation "I" should be applied on the front side of such funds.

Measuring instruments used for educational purposes are not subject to periodic verification, and the designation “U” is applied to them; it is prohibited to use such instruments for measurements.

Extraordinary verification of MI is carried out by the bodies of the SMS and MS of business entities during the operation and storage of MI, regardless of the period of periodic verification in the following cases:

1. If necessary, confirmation of the suitability of SI for use;
2. When putting the MI into operation after long-term storage;
3. When adjusting calibration intervals;
4. When monitoring the results of periodic verification;
5. If the verification mark, seal is damaged or the document confirming is lost, the measuring instrument has passed the necessary verification;
6. When measuring instruments are used as components, transferred for long-term storage or sent to the consumer after half of the calibration interval for them.

Inspection verification is carried out selectively in the implementation of state metrological supervision and control by business entities over the state and use of measuring instruments to determine their suitability for use, assess the quality of verification work and the correctness of assigning calibration intervals according to operating conditions. The results of the inspection verification are indicated in the act of verification of the state and application of the measuring instruments.

If the MI is in an unsatisfactory condition, the verification marks are extinguished, the certificates are canceled, and an entry is made in the passports or operational documentation about the unsuitability of the SI for use.

Expert verification is carried out during the metrological examination of measuring instruments by the bodies of the state metrological service. This verification is carried out in order to substantiate the conclusion about the suitability of the SI for use at the written request of the police, judicial and investigative authorities and the State Arbitration, as well as at the request of enterprises and organizations, indicating the reason.

If the expert verification data indicate abuse, the head of the state metrological service body is obliged to report this to the investigating authorities.

The results of expert verification are reflected in the conclusion, which is approved by the head of the body of the state metrological service.

Verification schemes.

Verification is carried out according to verification schemes that establish a system for transferring the size of a unit of physical quantity from the state standard to working SI.

A verification scheme is a duly approved document that establishes the means, methods and accuracy of transferring unit sizes from a standard or original exemplary measuring instrument to a working measuring instrument. Requirements for the content and construction of schemes are established by GOST 8.061-80.

Schemes are divided into state, departmental and local. State verification schemes are developed by the Main Center for State Standards, which is the custodian of the state standard of a unit of a given quantity and is approved as a state standard. The lower verification schemes are developed by business entities.

The verification scheme must include at least two unit size transfer steps. In the verification scheme, the transfer of the size of only one physical quantity should be presented. Schemes should consist of a text part and a drawing.

The text part of the scheme consists of an introductory part and explanations for the elements of the verification scheme, which carry additional information. The introductory part covers the purpose of GPE and GPS, the main MX of the standard and the procedure for transferring the size of a unit of physical quantity from the primary standard using secondary standards and exemplary SI to working tools.

The text provides a scientific and technical justification for verification schemes from the standpoint of the optimality of the scheme structure, i.e. exemplary SI, number of size transfer steps, etc. This justification should be carried out taking into account the following:

• Optimal ratios of the error of the calibrated and exemplary measuring instruments;
• Admissible probability of recognizing a metrologically faulty measuring instrument as suitable;
• Permissible ratio of the number of metrologically correct but rejected measuring instruments to the total number of metrologically correct measuring instruments.

Further in the text part, sections are given: standards, exemplary SI, working SI. Each section begins with a list of SI that can be used as reference and exemplary. MX, confidence probabilities are indicated when determining errors. The names of measuring instruments that can be verified by standards or exemplary measuring instruments are given, indicating the verification method and its error.

The graphical part of the verification scheme should consist of several horizontal fields corresponding to the steps of transferring the size of a physical quantity unit from the state standard to working SI. The name of the fields is indicated on the left side of the drawing (standards, exemplary SI of the 1st category, SI of the 2nd category, etc., working SI). In the upper field of the drawing of the verification scheme, the names of the standards are indicated in the order of their subordination. Under the field of standards there is a field of exemplary SI of the 1st category, 2nd category, etc. Under the field of the exemplary measuring instrument of the lowest category, the fields of working measuring instruments are placed, from left to right in descending order of accuracy: the highest, highest, high, medium and lowest accuracy.

The names of standards, exemplary and working SI are enclosed in rectangles indicating nominal values ​​or measurement ranges and errors. The name of the verification methods is enclosed in circles or horizontal ovals, which are located between the rectangles with the name of the SI. It also indicates the permissible error of the verification method.

Metrological characteristics of measuring instruments in the diagrams should be presented as follows:

1. errors of standards according to GOST 8.057-80:

a) not excluded systematic error;

b) random error;

c) instability;

1. errors of exemplary SI, expressed:

a) the limit of permissible error ( , 0 - respectively for the absolute and relative form);

b) confidence error (, 0 - respectively for the absolute and relative form);

1. error of working measuring instruments, expressed by the limit of permissible error.

Confidence probability is selected from the range: 0.90; 0.95; 0.99.

Names of measuring instruments, their nominal values ​​and ranges of values ​​of physical quantities, errors in verification schemes must comply with standards and specifications.

The verification methods on the diagrams must correspond to one of the following general methods:

1. direct comparison (without means of comparison);
2. comparison using a comparator or other means of comparison;
3. verification of SI according to an exemplary measure by measuring the value reproduced by the measure;
4. direct measurement by an exemplary measuring instrument of the value of a reproducible measure subjected to verification;
5. indirect measurement of a quantity by a reproducible measure or a measurable instrument that is being verified.

In metrological practice, there is an independent (autonomous) verification, i.e. verification without the use of exemplary measuring instruments. This verification arose during the development of highly accurate measuring instruments, which cannot be verified by traditional methods due to the lack of even more accurate measuring instruments with the appropriate measurement limits.

The essence of the method is to compare the quantities reproduced by the individual elements of the circuit of the verified MI with the value chosen as the reference and structurally reproducible in the calibrated MI itself. For example, when checking the m-th decade of a potentiometer, it is necessary to make sure that the voltage drops on each n-th degree of this decade are equal. In this case, having chosen the resistance of the first stage of the decade as a reference value, it is possible to compare the voltage drops across this resistance using a comparator in turn.

The ratio of permissible errors of exemplary and verified measuring instruments is established taking into account the accepted method of verification, the nature of the errors and other factors. Usually this ratio is taken equal to 1:3, subject to the introduction of corrections for the indications of exemplary measuring instruments. In the absence of amendments, a ratio of 1:5 is assumed.

Requirements for normal measurement conditions during verification.

Normal conditions are normalized by the limits of the normal areas of the influencing quantities, indicating, if necessary, their nominal values.

The conditions are considered normal for determining the basic error of the calibrated MI, if the error component of the calibrated MI from the action of the totality of influencing quantities does not exceed 35% of the limit of its permissible basic error.

If the exemplary and auxiliary means and their normal conditions differ from those established by the normative documents for verified, then the magnitude of the error component of the measurement result of other quantities should not exceed 50% of the basic error limit of their exemplary measuring instrument.

The limits of permissible errors of the calibrated MI from the action of any influencing quantity are selected from the range of 10, 15, 20 and 35% of the limit of its permissible basic error.

When choosing the normalized limits, the error from the action of influencing quantities can be taken into account according to the following dependence

where S-s.c.o. errors from the action of a combination of influencing quantities;

S - s.c.o. errors from the action of each of (N - m) with a weight taken as 1;

N is the number of acting uncorrelated influencing quantities;

m is the number of values ​​that affect the increase in the weight of B1, B2, ..., Bm.

If it is necessary to take into account the weight of an individual influencing quantity, the square of its value is added to the number of effective influencing quantities, reduced by 1, and the corresponding normalized limit should be multiplied by the weight taken into account.

According to the RD, the nominal values ​​of the influencing quantities used in the verification of measuring instruments are as follows:

Normal conditions during the test must be observed in the working space, within which the normal range of influencing quantities lies within the established limits.

ND is allowed to set the integral characteristics of the influencing quantities, for example, vibration parameters, refractive indices of normal air or its density.

The nominal values ​​of influencing quantities, such as magnetic and electrostatic field strengths, should correspond to the characteristics of these Earth fields in a given geographical area.

General requirements for the premises of verification departments.

where b is the attenuation coefficient;

L - attenuation power, dB;

F is the frequency of the electromagnetic field, Hz.

The attenuation of vibrations when screening rooms with meshes depends on the mesh pitch, wire diameter, wavelength and angle of incidence.

According to the degree of attenuation of electromagnetic energy, the shielding of the room is divided into 4 classes: class 1 - 80140 dB; Class 2 - 6080 dB; 3 class - 3060 dB; Class 4 - less than 30dB. Building materials (concrete, brick, silicate blocks) provide attenuation of electromagnetic energy by 10 - 20 dB. Design features of each class of shielded rooms:

Grade 1 - has a closed, complex sheet metal screen without windows or peepholes, with double screened doors with a lock to keep only one door open. If it is not possible to switch off the device or the installation, a third door with a lock should be used. Radiations penetrating through various technological openings are attenuated by filters, diaphragms and traps.

Class 2 - a solid screen, there is only one door, and if it is impossible to turn off the equipment - two doors.

Grade 3 - has one door. If the equipment operates at a constant frequency, then it is allowed to use a double metal mesh for the screen.

Class 4 - shielding is carried out with a metal mesh. It is allowed to have windows, viewing openings and doors closed with mesh or metallized glass.

9. In the calibration rooms there should be a ground bus, a washbasin with hot and cold water and e / towel.