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NITP 2 Area Measuring Instruments - National Measurent Institute

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NITP 2 Area Measuring Instruments - National Measurent Institute

i

? Commonwealth of Australia 2011

NMI V 12

    First edition December 2004

    First edition, first revision September 2005

NITP 2

    First edition December 2011

    First edition, first revision December 2012

    National Measurement Institute

    Bradfield Road, Lindfield, NSW 2070

    PO Box 264, Lindfield, NSW 2070

    T (61 2) 8467 3600

    F (61 2) 8467 3610

    W www.measurement.gov.au

    AMENDMENTS

    Item no Date Page Location Details of change

    Deleted references to certification, updated information,

    1 01/12/2012 all all clarified meaning, provided hyperlinks for all referenced

    documents and made minor editorial changes.

    Reworded requirements for instrument characteristics to a 2 01/12/2012 1 to 2 clause 3.2 statement (from a question).

    Revised the headings to better reflect the content within the clauses 4.1 and 3 01/12/2012 2 sections. 4.1.2

    Clarified the manner in which the MPE is calculated and 4 01/12/2012 2 clause 4.1.1 applied for area measuring instruments with a digital indication.

    Added a section to record details of equipment and reference 5 01/12/2012 5 test report standards.

    Added a section to record results of the mean measurement

    6 01/12/2012 6 test report error at the three reference points and incorporated section to

    record the overall result of the test.

    Added a section to record results of the single measurement

    7 01/12/2012 7 test report error at the five reference points and incorporated section to

    record the overall result of the test.

    PREFACE

    On 30 June 2010, the uniform test procedures (i.e. relevant NMI V documents) were deemed to be

    national instrument test procedures (NITPs) for the purposes of section 18GG of the National

    Measurement Act 1960 (Cth).

    In 2011, the NITPs were renumbered to better align the numbers with the classes of pattern approval

    and servicing licensee. As a result, this document (previously NMI V 12) became NITP 2. The amendments that have been made to the latest edition of this document include its rebranding,

    renumbering, renaming and updating of cross-references. In all other respects, this document is

    identical to NMI V 12.

    NMI’s Chief Metrologist has determined that NITP 2 contains the test procedures for the verification of

    area measuring instruments.

    ABBREVIATIONS

    e verification scale interval

    Max maximum

    Min minimum

    MPE maximum permissible error

    MPE maximum permissible error of an area measuring with analog indication analog

    MPE maximum permissible error of an area measuring instrument with digital indication digital

    scale interval scale interval of the area measuring instrument with digital indication

    ii

    CONTENTS

    Amendments ...................................................................................................................................... ii

    Preface............................................................................................................................................... ii

    Abbreviations...................................................................................................................................... ii

    Explanation of Terms ..........................................................................................................................iv

    1. Scope ......................................................................................................................................... 1

    2. Equipment................................................................................................................................... 1

    3. Visual Inspection ......................................................................................................................... 1

    3.1 Required Data .................................................................................................................... 1

    3.2 Characteristics of the Instrument ......................................................................................... 1

    4. Test Procedures .......................................................................................................................... 2

    4.1 Measurement Error ............................................................................................................. 2

    4.2 Testing Procedure for Single Measurement Error ................................................................ 2

    4.3 Testing Procedure for Mean Measurement Error ................................................................. 3

    4.4 Additional Tests .................................................................................................................. 3

    5. Suggested Sequence for Testing Procedures .............................................................................. 4

    Appendix A. Test Report ..................................................................................................................... 4

    iii

    EXPLANATION OF TERMS

    For explanations of other terms see General Information for Test Procedures.

    Adjustment

    Alteration of the measurement parameters to bring the instrument in use within the allowable MPEs. Calibration

    The set of operations that (under specified conditions) establishes the relationship between the indicated or nominal value of an instrument and the corresponding known value of the measured quantity.

    In-service Inspection

    The examination of an instrument by a trade measurement inspector to check that:

    ; the verification mark is valid; and

    ; the errors do not exceed the MPEs permitted for an in-service inspection.

    An in-service inspection does not permit the instrument to be marked with a verification mark. Verification

    The examination of an instrument by a trade measurement inspector, servicing licensee or

    employee of a servicing licensee in order to mark the instrument indicating that it conforms with the relevant test procedures.

    Initial verification is the verification of a new instrument that does not bear a verification mark and has never been verified before.

    iv

1. SCOPE ; the required data; and

    NITP 2 describes the test procedures for the ; the applicable characteristics of the verification and in-service inspection of area instrument.

    measuring instruments (some of which are 3.1 Required Data commonly known as leather-measuring

    1. Test report number. instruments) to assess if they measure within

    the maximum permissible errors (MPEs) 2. Date of test. specified in Schedule 1 of the National Trade

    3. Verifier’s name. Measurement Regulations 2009 (Cth) and that

    they comply with the relevant certificate of 4. Type of test: verification or in-service approval. inspection (ensure that the verification mark Certificates of approval are based on is in place for in-service inspection and NMI M 3. Pattern Approval Specifications for reverification). Area Measuring Instruments. Refer to NMI M 3 5. Name of owner/user. for all metrological and technical requirements.

    All instruments must also comply with the 6. Address of owner/user. National Measurement Act 1960 (Cth), the 7. Name of contact person on premises. National Measurement Regulations 1999 (Cth)

    and the National Trade Measurement 8. Address of instrument location. Regulations 2009 (Cth). 9. Description of instrument. The test procedures described in this document 10. Manufacturer. are for area measuring instruments in which the

    article to be measured: 11. Model. (a) remains in a stationary position on the 12. Serial number. measuring table while it is being measured;

    or 13. Certificate of approval number. (b) is conveyed beneath the measuring device

    14. The non-metrological characteristics while it is being measured.

    including: Max, Min and the verification (e) 2. EQUIPMENT scale interval.

    1. Certificate(s) of approval. 3.2 Characteristics of the Instrument 2. Appropriate reference standards of area Where applicable, the area measuring measurement, namely standard area test instrument and its use shall comply with the templates as close as practical to the following statements. following denominations: 10, 20, 50 and 21. The area measuring instrument shall 100 dm.

    comply with its certificate(s) of approval. Note: Test templates shall have values,

    which are an integral number of 2. The instrument shall be used in an 2square decimetres (dm). appropriate manner.

    The reference standards of measurement 3. All mandatory descriptive markings shall be shall comply with the uncertainties and clearly and permanently marked on a data variations permitted in the National plate that is fixed to the instrument. Measurement Regulations 1999 (Cth). The

    combined uncertainties and variations shall 4. The data plate shall be fixed on the

    be less than one-third the MPE of the area instrument.

    measuring instrument under test. 5. The instrument shall be complete, clean

    Record details of the reference standards of and in an operational condition.

    measurement used on the test report. 6. The instrument shall be free of any 3. Current Regulation 13 certificates for all apparent obstructions.

    reference standards of measurement. 7. The instrument shall be securely mounted 4. Test report (see Appendix A). on a firm and level base. 3. VISUAL INSPECTION 8. The operator (and where applicable, the

    customer) shall have a clear and Visually inspect the area measuring instrument unobstructed view of the indicating device and record on the test report details of: and the complete measuring process.

    12/2012 NITP 2, v1.1 1 of 7

     = MPE + (0.5 x scale interval) MPE9. The instrument shall be adequately digitalanalog

    protected against abnormal dust, air where movement, vibrations, atmospheric

    conditions and any other influence likely to MPE is the MPE of the area measuring digital2affect its performance. instrument with digital indication (dm)

    MPE is the MPE of the area measuring 4. TEST PROCEDURES analog2with analog indication (dm) The following series of test procedures

    Scale interval is the scale interval of the determine if the performance of an area

    area measuring instrument with digital measuring instrument meets the criteria and 2indication (dm) whether the instrument requires adjustment or

    service. For example the in-service inspection MPE for

    an analog instrument with a scale interval of Each test procedure is explained as a discrete 2221 dm at 20 dm is: ?1 dm. test. However, some tests may be combined to

    expedite the testing procedure. A suggested The in-service inspection MPE for a digital sequence for testing is shown in clause 5. 2instrument with a scale interval of 1 dm at 220 dm is: Record results on the test report.

    222MPE = 1 dm + (0.5 x 1 dm) = 1.5 dm. 4.1 Measurement Error digital

    The instrument is tested by measuring a known

    area template or a combination of known area Table 2. Adjustments to the MPE for digital templates and recording the indication for: displays (a) the measurement of a single template and Scale In-service the mean reading of twenty measurements Verification interval inspection of a single template; and/or

    2(b) the measurement of a combination of 0.1 dm No change No change templates and the mean reading of twenty

    measurements of the same combination of 21 dm No change Add 0.5 scale templates. interval

    4.1.1 Single Measurement Error The MPEs for verification and in-service 4.1.2 Mean Measurement Error inspection of instruments with analog indication

    On analog and digital indicating instruments, shall be in accordance with Table 1 or as

    the mean of 20 measurements shall not differ specified in the certificate of approval, where

    from the denominated value of the template by the certificate is issued on or after 1 July 2007.

    more than one-half of the MPE specified in clause 4.1.1.

    Table 1. Maximum permissible error 4.1.3 Caution 2) MPE (dmWhen templates are placed on the instruments, Area of care must be taken to ensure that: template(s) In-service 2(a) the templates do not extend beyond the Verification (dm) inspection limits of the measuring area of the

    conveyor or of the measuring table; Not exceeding ?0.5 ?1 (b) when using a combination of templates, 25

    there is no over-lapping of the templates

    ?0.5 (+1 for each ?1 (+2 for each as they pass beneath the measuring 22Exceeding 25 additional 50 dm additional 50 dm device; and

    or part thereof) or part thereof) (c) the templates are staggered across the

     field of measurement.

    Instruments with digital indication may require 4.2 Testing Procedure for Single rounding in some instances. These instances Measurement Error are specified in Table 2. Where rounding is The instrument is tested at a minimum of five applied to instruments with digital indication, different reference points throughout the the MPE shall be calculated using the following measuring range in approximately equal steps formula: unless otherwise specified by the certificate of

    approval.

    12/2012 NITP 2, v1.1 2 of 7

    The reference points shall include minimum 4.3 Testing Procedure for Mean and maximum areas. Measurement Error

    The instrument is tested at a minimum of three Each reference point may be achieved by use

    different reference points in approximately of one or a combination of area template(s).

    equal steps unless otherwise specified by the 4.2.1 Measurement Sensors Test certificate of approval. 1. Select one area template that is Each reference point may be achieved by using approximately one-third the width of the one or a combination of multiple area templates. measurement receptor.

    1. Select one or more area templates to test Note: The area of this template must be the instrument at one of the three selected greater than the minimum area. reference points. 2. Ensure zero is displayed or use zero 2. Ensure zero is displayed or use zero preset. preset. 3. Place the template on the extreme left of 3. Place the template(s) centrally on the the measurement receptor. measurement receptor. 4. Operate the instrument and take a reading. 4. Operate the instrument and take a reading. 5. Record the result on the test report. 5. Record the result on the test report. 6. Repeat steps 2 to 5 by placing the 6. Repeat steps 2 to 5 for a further 19 template centrally on the measurement measurements. receptor.

    7. Calculate the mean error. 7. Repeat steps 2 to 5 by placing the

    template at the extreme right of the 8. Repeat steps 1 to 7 for each of the measurement receptor. remaining selected reference points. 4.2.2 Reference Points Test 4.4 Additional Tests 1. Select one or more area template(s) to test 1. Where the instrument is fitted with two or the instrument at one of the remaining more measuring heads, repeat the tests reference points. described in clauses 4.1 to 4.3 for each

    head. 2. Ensure zero is displayed or use zero

    preset. 2. Where the instrument is fitted with a

    totaliser, ensure that it is operating 3. Place the template(s) centrally on the

    correctly throughout the tests. measurement receptor.

    3. For additional indicating and printing 4. Operate the instrument and take a reading.

    devices, ensure that they exactly repeat 5. Record the result on the test report. the information on the primary indication

    and/or ticket/label-printing device, and that 6. Repeat steps 2 to 5 for each of the

    they comply with the applicable general remaining reference points.

    supplementary certificate of approval.

    4. Where the instrument is fitted with a

    stamper, ensure that it is operating

    correctly.

    5. Apply any further tests required by the

    certificate(s) of approval. 12/2012 NITP 2, v1.1 3 of 7

    5. SUGGESTED SEQUENCE FOR APPENDIX A. TEST REPORT

    TESTING PROCEDURES

    The following test report contains the minimum 1. Check the certificate of approval for any amount of information that must be recorded. additional tests required. Make provision

    If the certificate of approval requires additional for including these tests in the testing

    tests, attach pages that record the results of sequence.

    these tests. 2. Visually inspect the area measuring

    Number each page of the test report in the style instrument and make note of its

    shown at the top of each of the following pages. metrological characteristics.

    3. Determine the reference points for the

    tests.

    4. Conduct the accuracy tests to determine

    the single measurement error.

    5. Conduct the accuracy tests to determine

    the mean error.

    6. Conduct any additional tests that are

    required to complete the testing, including

    if necessary, any additional testing

    required by the certificate of approval. 7. Complete the test report.

    8. Determine whether the instrument has

    passed or failed.

    9. Carry out anything else needed to

    complete the procedure. See General

    Information for Test Procedures for more

    details. This may include:

    ; obliterating the verification mark from

    the instrument;

    ; applying a verification mark; and

    ; applying a seal.

    12/2012 NITP 2, v1.1 4 of 7

    Page … of …

    Test Report for Area Measuring Instruments Test report reference number ................................................... Date of test .................................................... Type of test (tick one) ; Verification ; In-service inspection

    For in-service inspection, record the verification mark ..................................................................................... Name of owner/user ........................................................................................................................................ Address of owner/user .................................................................................................................................... Name of contact on premises .......................................................................................................................... Address where the instrument is located ......................................................................................................... Description of instrument ................................................................................................................................ Manufacturer ................................................................... Model ..................................................................... Serial number ............................................. Certificate(s) of approval number ................................................ Max .................................... Min .......................................................... Verification scale interval .................... Details of the Equipment and Reference Standards of Measurement (clause 2)

    Make

    Serial number

    2Nominal value of template (dm)

    Regulation 13 certificate number

    Certificate expiry date

    Characteristics of the Instrument (clause 3.2)

     yes, no or

    N/A

    Does the instrument comply with its certificate(s) of approval?

    Is the instrument being used in an appropriate manner?

    Are all mandatory markings clearly and permanently fixed on the instrument in the prescribed

    location?

    Is the data plate fixed on the instrument?

    Is the instrument complete, clean and in an operational condition?

    Are there any apparent obstructions to the operation of the instrument?

    Is the instrument securely mounted on a firm and level base?

    Does the operator (and where applicable the customer) have a clear and unobstructed view of

    the indicating device and the complete measuring process?

    Is the instrument adequately protected against abnormal dust, air movement, vibrations,

    atmospheric conditions and any other influence likely to affect its performance?

12/2012 NITP 2, v1.1 5 of 7

    Page … of …

    Mean Measurement Error (clause 4.3)

    2 dmFirst Second Third

    reference reference reference Error

    point point point Error Error

    Actual Run # 1 Run # 2 Run # 3 Run # 4 Run # 5 Run # 6 Run # 7 Run # 8 Run # 9 Run # 10 Run # 11 Run # 12 Run # 13 Run # 14 Run # 15 Run # 16 Run # 17 Run # 18 Run # 19 Run # 20 Mean error

    ; Pass ; Fail First reference point Overall result

    ; Pass ; Fail Second reference point

    ; Pass ; Fail Third reference point

12/2012 NITP 2, v1.1 6 of 7

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