SIST EN 62058-11:2010

Electricity metering equipment (a.c.) - Acceptance inspection - Part 11: General acceptance inspection methods (IEC 62058-11:2008, modified)

IEC 62058-11:2008 specifies the general acceptance inspection methods which apply to newly manufactured electricity meters produced and supplied in lots of 50 and above.

Wechselstrom-Elektrizitätszähler - Annahmeprüfung - Teil 11: Allgemeine Verfahren zur Annahmeprüfung (IEC 62058-11:2008, modifiziert)

Equipement de comptage de l'électricité (c.a.) - Contrôle de réception - Partie 11: Méthodes générales de contrôle de réception (CEI 62058-11:2008, modifiée)

La CEI 62058-11:2008 spécifie les méthodes générales de contrôle de réception qui s'appliquent aux compteurs électriques neufs et livrés par lots de 50 et plus.

Merjenje električne energije (a.c.) - Sprejemna kontrola - 11. del: Splošne metode sprejemne kontrole (IEC 62058-11:2008, spremenjen)

Splošne metode sprejemnih kontrol, določene v tem delu IEC 62058, veljajo za na novo izdelane naprave za merjenje električne energije, proizvedene in dobavljene v pošiljkah 50 kosov ali več.

General Information

• Status: Published
• Publication Date: 13-Jul-2010
• ICS: 17.220.20 - Measurement of electrical and magnetic quantities
• ICS: 91.140.50 - Electricity supply systems
• Technical Committee: MEE - Equipment for electrical energy measurement and load control
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 30-Jun-2010
• Due Date: 04-Sep-2010
• Completion Date: 14-Jul-2010
• Directive: 2004/22/EC - Directive 2004/22/EC of the European Parliament and of the Council of 31 March 2004 on measuring instruments
• Directive: 2014/32/EU - Directive 2014/32/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of measuring instruments
• Mandate: M/347 - Programming mandate to CEN, CENELEX and ETSI relating to measuring instruments
• Mandate: M/374 - Mandate to CEN and CENELEC for standards in the field of measuring instruments
• Ref Project: EN 62058-11:2010 - Electricity metering equipment (a.c.) - Acceptance inspection - Part 11: General acceptance inspection methods

Relations

• Replaces: SIST EN 60514:1995 - Acceptance inspection of Class 2 alternating-current watthour meters
• Effective Date: 01-Sep-2010
• Replaces: SIST EN 61358:1997 - Acceptance inspection for direct connected alternating current static watt-hour meters for active energy (classes 1 and 2)
• Effective Date: 01-Sep-2010
• Revised: SIST EN 61358:1997 - Acceptance inspection for direct connected alternating current static watt-hour meters for active energy (classes 1 and 2)
• Effective Date: 07-Jun-2022
• Revised: SIST EN 60514:1995 - Acceptance inspection of Class 2 alternating-current watthour meters
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2010
1DGRPHãþD
SIST EN 60514:1995
SIST EN 61358:1997
0HUMHQMHHOHNWULþQHHQHUJLMHDF6SUHMHPQDNRQWURODGHO6SORãQHPHWRGH
VSUHMHPQHNRQWUROH,(&VSUHPHQMHQ
Electricity metering equipment (a.c.) - Acceptance inspection - Part 11: General
acceptance inspection methods (IEC 62058-11:2008, modified)
Wechselstrom-Elektrizitätszähler - Annahmeprüfung - Teil 11: Allgemeine Verfahren zur
Annahmeprüfung (IEC 62058-11:2008, modifiziert)
Equipement de comptage de l'électricité (c.a.) - Contrôle de réception - Partie 11:
Méthodes générales de contrôle de réception (CEI 62058-11:2008, modifiée)
Ta slovenski standard je istoveten z: EN 62058-11:2010
ICS:
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 62058-11
NORME EUROPÉENNE
June 2010
EUROPÄISCHE NORM
ICS 17.220; 91.140.50 Supersedes EN 60514:1995 (partially), EN 61358:1996 (partially)

English version
Electricity metering equipment (a.c.) -
Acceptance inspection -
Part 11: General acceptance inspection methods
(IEC 62058-11:2008, modified)
Equipement de comptage  Wechselstrom-Elektrizitätszähler -
de l'électricité (c.a.) - Annahmeprüfung -
Contrôle de réception - Teil 11: Allgemeine Verfahren
Partie 11: Méthodes générales zur Annahmeprüfung
de contrôle de réception (IEC 62058-11:2008, modifiziert)
(CEI 62058-11:2008, modifiée)
This European Standard was approved by CENELEC on 2010-06-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2010 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62058-11:2010 E
Foreword
The text of document 13/1430/FDIS, future edition 1 of IEC 62058-11, prepared by IEC TC 13, Electrical
energy measurement, tariff- and load control, was submitted to the IEC-CENELEC parallel vote.
A draft amendment, prepared by the Technical Committee CENELEC TC 13, Equipment for electrical
energy measurement and load control, was submitted to the formal vote.
The combined texts were approved by CENELEC as EN 62058-11 on 2010-06-01.
EN 62058-31:2010, EN 62058-11:2010 supersedes EN 61358:1996.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2011-06-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2013-06-01
This European Standard has been prepared under a mandate given to CENELEC by the European
Commission and the European Free Trade Association and covers essential requirements of
EC Directive 2004/22/EC. See Annex ZZ.
Annexes ZA and ZZ have been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 62058-11:2008 was approved by CENELEC as a European
Standard with agreed common modifications as given below.
COMMON MODIFICATIONS
1 Scope
Add the following text at the end of Clause 1:
The process described herein can be used for assessment of conformity with the requirements of the
Directive 2004/22/EC of the European Parliament and of the Council on measuring instruments (MID),
using:
- Module D, Declaration of conformity to type based on quality assurance of the production process:
- Final product inspection and testing;
- Module F, Declaration of conformity to type based on product verification:
- Verification of conformity with the metrological requirements by examination and testing of every
instrument; or
- Statistical verification of conformity with the metrological requirements;
- Module H1, Declaration of conformity based on full quality assurance plus design examination:
- Final product inspection and testing.
When the process is used within module F, the inspection methods selected shall meet the requirements
specified in 5.3 of Annex F of the MID. See 5.5 below.

- 3 - EN 62058-11:2010
It is noted, that the requirements of 5.3 of Annex F of the MID do not take into account the switching rules
between normal, tightened and reduced inspection. Those switching rules, mandatory with lot-by-lot
inspection, when properly applied, ensure adequate protection to the customer against poor quality, and
provide incentives to the manufacturer to produce consistently good quality.
5 General
5.5 Selection of sampling schemes and sampling plans
Add the following text after Figure 1:
When acceptance inspection within Module F of the MID is performed, only those sampling schemes and
plans may be used, which meet the requirements of 5.3 of Annex F of the MID quoted below:
The statistical procedure shall meet the following requirements:
The statistical control will be based on attributes. The sampling system shall ensure:
- a level of quality corresponding to a probability of acceptance of 95 %, with a non-conformity of less
than 1 %;
- a limit quality corresponding to a probability of acceptance of 5 %, with a non-conformity of less than
7 %.
NOTE It is understood that the correct text should be : …non-conformity of more than 7 %.
See Clauses 6.Z1, 7.6, 8.4, 8.5 and 10.1.
6 100 % inspection
Add the following subclause after 6.3:
6.Z1 Statistical properties
Statistical properties (OC curves) for 100 % inspection are not available.
7 Lot-by-lot inspection by attributes
7.6 Operating characteristic (OC) curves
Add the following text after Table 10:
In the case for inspecting for non-critical nonconformities, as it can be seen from Table 9, Tabulated
values of OC curves for single sampling, AQL = 1,0 plans, the requirements of 5.3 of Annex F of the MID
are met when sampling plans with sample size code letter K and L are used.
In case of inspecting for critical nonconformities, accept zero plans are used. Therefore, the requirement
of the first bullet point of 5.3 of Annex F of the MID (probability of acceptance of 95 %) is not applicable.
As it can be seen from Table 10, Tabulated values of OC curves for single sampling inspection accept
zero sampling plans, the requirement of the second bullet point is met when sampling plans with sample
size code letter H, J, K and L are used.
8 Isolated lot inspection
8.4 Procedure A
Add the following text after Table 19 and the Example:
For sampling plans with zero acceptance number, the probability of acceptance depends on the actual lot
size and the number of nonconforming units in the lot. See Table 19.
For sampling plans with non-zero acceptance numbers the OC curves are well approximated by the
tabulated performance of the same plans in Procedure B. See Table 20.
8.5 Procedure B
Add the following text after Table 22:
As it can be seen from Table 20, the requirements of 5.3 of Annex F of the MID are met when sampling
plans with sample size code letter K and L are used.

10 Lot-by-lot inspection by variables
10.1 Application of the method
Add the following text after the Note:
According to 5.3 of Annex F of the MID, inspection by variables is not allowed.
____________
- 5 - EN 62058-11:2010
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

ISO 2859-1 1999 Sampling procedures for inspection by - -
+ corr. March 2001 attributes -
Part 1: Sampling schemes indexed by
acceptance quality limit (AQL) for lot-by-lot
inspection
ISO 2859-2 1985 Sampling procedures for inspection by - -
attributes -
Part 2: Sampling plans indexed by limiting
quality (LQ) for isolated lot inspection

ISO 2859-3 2005 Sampling procedures for inspection by - -
attributes -
Part 3: Skip-lot sampling procedures

ISO 3534-2 2006 Statistics - Vocabulary and symbols - - -
Part 2: Applied statistics
ISO 3951-1 2005 Sampling procedures for inspection by - -
variables -
Part 1: Specification for single sampling plans
indexed by acceptance quality limit (AQL) for
lot-by-lot inspection for a single quality
characteristic and a single AQL

ISO 3951-2 2006 Sampling procedures for inspection by - -
variables -
Part 2: General specification for single
sampling plans indexed by acceptance quality
limit (AQL) for lot-by-lot inspection of
independent quality characteristics

ISO 5479 1997 Statistical interpretation of data - Tests for - -
departure from the normal distribution

Annex ZZ
(informative)
Coverage of Essential Requirements of EC Directives
This European Standard has been prepared under the mandate M/374 given to CENELEC by the
European Commission and within its scope, the standard covers methods for statistical verification of
conformity with the metrological requirements in connection the Modules F, D and H1.
EN 62058-11 specifies sampling plans, schemes and systems for lot-by-lot inspection by attributes or
variables. In addition, a test procedure for 100 % inspection is specified, that can be used if the lot size is
too small for sampling inspection or when sampling inspection has to be discontinued.
Table ZZ.1 provides the relationship between the Essential requirements of the MID and the stipulations
of the EN 62058 series.
Compliance with this standard provides one means of conformity with the specified essential
requirements of the Directives concerned.
WARNING: Other requirements and other EC Directives may be applicable to the products falling within
the scope of this standard.
- 7 - EN 62058-11:2010
Table ZZ.1 – Relationship between the Essential requirements of the MID
and the stipulations of the relevant standards

MID Annex I Subject EN 62058-11 EN 62058-21 EN 62058-31
NOTE The text in this column is
for orientation. For the full text see
the MID.
1 Allowable Errors
1.1 Under rated operating conditions 5.6 Accuracy 5.6 Accuracy
and in the absence of disturbance tests, Table tests, Table
Z2 Z2
–
5.7 5.7
Verification of Verification of
the register the register
1.2 Under rated operating conditions
– – –
and in the presence of disturbance
1.3 Climatic, mechanical and EM
environment and other influence
– – –
quantities to be specified by the
manufacturer
1.3.1 Climatic environments, upper and
– – –
lower temperature limit
1.3.2 Mechanical environments,
– – –
vibration and shock
1.3.3 Electromagnetic environments,
unless otherwise laid down in the
– – –
appropriate instrument-specific
annexes.
1.3.4 Other influence quantities – – –
1.4 Carrying out the tests – – –
1.4.1 Basic rules for testing and 5.6, 5.6,
–
determination of errors Accuracy test Accuracy test
1.4.2 Ambient humidity – – –
2 Reproducibility – – –
3 Repeatability – 4.3 4.3
4 Discrimination and Sensitivity – – –
5 Durability – – –
6 Reliability – – –
7 Suitability 5.3 5.3
AC voltage AC voltage
test test
7.1 No feature likely to facilitate
fraudulent use, possibilities for – – –
unintentional misuse minimal
7.2 Suitable for intended use under
practical working conditions, no – – –
unreasonable demand of the user

MID Annex I Subject EN 62058-11 EN 62058-21 EN 62058-31
7.3 Errors of a utility measuring
instrument at flows or currents
– – –
outside the controlled range not
unduly biased.
7.4 When the measurand is constant
over time, the measuring
instrument shall be insensitive to
N.A. N.A. N.A.
small fluctuations of the value of
the measurand, or shall take
appropriate action.
7.5 Robust and materials of
construction suitable for the – – –
intended use conditions.
7.6 Designed so as to allow the control
of the measuring tasks after the
instrument has been placed on the
market and put into use.
Software that is critical for the
– – –
metrological characteristics
identifiable.
Metrological characteristics not
inadmissibly influenced by the
associated software.
8 Protection against corruption – – –
8.1 Metrological characteristics not
influenced in any inadmissible way
by the connection to it of another
device, by any feature of the – – –
connected device itself or by any
remote device that communicates
with the measuring instrument.
8.2 Hardware component critical for
metrological characteristics
designed so that it can be secured.
– – –
Security measures to provide
evidence of an intervention.
Software that is critical for metrological
8.3
characteristics shall be identified as such
and shall be secured.
– – –
Software identification.
Evidence of an intervention available for
a reasonable period of time.
Measurement data, critical software and
8.4
metrologically important parameters
stored or transmitted adequately – – –
protected against accidental or
intentional corruption.
For utility measuring instruments the
8.5
display of the total quantity supplied or
the displays from which the total quantity
supplied can be derived, whole or partial – – –
reference to which is the basis for
payment, shall not be able to be reset
during use.
- 9 - EN 62058-11:2010
MID Annex I Subject EN 62058-11 EN 62058-21 EN 62058-31
Information to be borne by and to
– – –
accompany the instrument
9.1 Shall bear the following
inscriptions:
- manufacturers mark or name;
- information in respect of
accuracy.
When applicable:
- information in respect of the
conditions of use;
– 5.2 5.2
- measuring capacity;
- measuring range;
- identity marking;
- number of the EC-type examination
certificate or the EC design
examination certificate;
- information whether or not additional
devices providing metrological
results comply with the provisions of
this Directive on legal metrological
control.
9.2 For too small instruments, marking
on packaging and in any N.A. N.A. N.A.
accompanying documents
9.3 Accompanying information on
- operation
and where relevant
- rated operating conditions;
- mechanical and
electromagnetic environment
classes;
- the upper and lower
temperature limit, whether
condensation is possible or
– – –
not, open or closed location;
- instructions for installation,
maintenance, repairs,
permissible adjustments;
- instructions for correct
operation and any special
conditions of use;
- conditions for compatibility with
interfaces, sub-assemblies or
measuring instruments.
9.4 Utility meters do not require
– – –
individual instruction manuals.
9.5 Decimal scale interval – – –
9.6 Material measure N.A. N.A. N.A.
9.7 Units of measurement and
symbols in accordance with – – –
Community legislation
9.8 Marks and inscriptions clear, non-
erasable, unambiguous and non- – – –
transferable.
MID Annex I Subject EN 62058-11 EN 62058-21 EN 62058-31
10 Indication of result – – –
10.1 Display or hard copy N.A. N.A. N.A.
10.2 Indication of result clear and
N.A. N.A. N.A.
unambiguous. Easy reading.
10.3 Hard copy easily legible and not
N.A. N.A. N.A.
erasable
10.4 Direct sales trading transactions N.A. N.A. N.A.
Fitted with a metrologically controlled
10.5
display accessible without tools to the
consumer.
5.7 5.7 5.7
Verification of Verification of Verification of
the register the register the register
The reading of this display is the
measurement result that serves as the
basis for the price to pay.
11 Further processing of data to
N.A. N.A. N.A.
conclude the trading transaction
11.1 Durable record of the
measurement result (other than N.A. N.A. N.A.
utility meter)
11.2 Durable proof of the measurement
N.A. N.A. N.A.
result
12 Conformity evaluation
Designed so as to allow ready
evaluation of its conformity with
– – –
the appropriate requirements of
this Directive.
Annex MI- ACTIVE ELECTRICAL ENERGY

003 METERS
1 Accuracy – – –
2 Rated operating conditions – – –
3 MPEs 5.6 Accuracy 5.6 Accuracy
tests, Table tests, Table
Z2 Z2
5.7 5.7
Verification of Verification of
the register the register
4 Permissible effect of disturbances – – –
4.1 General – Special EM environment – – –
4.2 Effect of disturbances of long
– – –
duration
Reversed phase sequence
– – –
Voltage unbalance (only applicable to

– – –
polyphase meters)
Harmonic contents in the current circuits
– – –
DC and harmonics in the current circuit
– – –
Fast transient bursts
– – –
- 11 - EN 62058-11:2010
MID Annex I Subject EN 62058-11 EN 62058-21 EN 62058-31
Magnetic fields
– – –
HF (radiated RF) electromagnetic field;
– – –
Conducted disturbances
introduced by radio-frequency – – –
fields
Oscillatory waves immunity – – –
4.3 Permissible effect of transient
– – –
electromagnetic phenomena
4.3.1 Behavior during and immediately
after a disturbance
– – –
Recovery
Critical change value
4.3.2 Critical change value for
– – –
overcurrent
5 Suitability
Measurement error below the rated
5.1
– – –
operating voltage
5.2 Display of total energy
- sufficient number of digits – – –
- not resettable during use
5.3 Retain energy register reading for
– – –
4 months
5.4 Running with no load 5.4 Test of 5.4 Test of
– no-load no-load
condition condition
5.5 Starting 5.5 Starting, 5.5 Starting,
–
Table Z1 Table Z1
6 Units – – –
7 Putting into use – – –
CONFORMITY ASSESSMENT Specifies
100% testing
B + F or B + D or H1.
and sampling
inspection
– –
methods to
support
modules F, D
and H1
IEC 62058-11
Edition 1.0 2008-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electricity metering equipment (AC) – Acceptance inspection –
Part 11: General acceptance inspection methods

Equipement de comptage de l'électricite (c.a.) – Contrôle de réception –
Partie 11: Méthodes générales de contrôle de réception

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XC
CODE PRIX
ICS 17.220; 91.140.50 ISBN 2-8318-9988-5
– 2 – 62058-11 © IEC:2008
CONTENTS
FOREWORD.6
INTRODUCTION.8
1 Scope.9
2 Normative references .9
3 Terms and definitions .9
3.1 Sources of data .10
3.2 Types of sampling .11
3.3 Specifications, values and test results.11
3.4 Types of inspection .12
3.5 Types of acceptance sampling inspection.14
3.6 Acceptance sampling inspection system aspects.15
3.7 Acceptance criteria.16
3.8 Types of operating characteristic curves.18
3.9 Terms relating to operating characteristics .18
3.10 Outgoing quality concepts .21
3.11 Other terms .21
4 Symbols and abbreviations.22
4.1 Symbols .22
4.2 Acronyms .23
5 General .23
5.1 The objectives of acceptance inspection .23
5.2 Acceptance sampling plans, schemes and systems .24
5.3 Practical and economic advantages of using standard sampling plans .24
5.4 Agreement between the parties .25
5.5 Selection of sampling schemes and sampling plans .26
5.6 Considerations influencing a selection.27
5.6.1 Long and short production runs .27
5.6.2 Lot-by-lot inspection .28
5.6.3 Isolated lot inspection.28
5.6.4 Attributes versus variables .28
5.6.5 Single and double sampling.29
5.6.6 “s” method and “σ” method.29
5.7 Nonconformity and nonconforming items .29
5.8 Classification of nonconformities .29
5.9 Operating characteristic (OC) curve .30
5.10 Producer’s risks (PR) and consumer’s risk (CR) .30
5.11 AQL, PRQ, LQ and CRQ .31
5.12 Switching rules for normal, tightened and reduced inspection.31
5.13 Inspection level .32
5.14 Sample size code letter .32
5.15 Place of inspection .33
5.16 Submission of product for acceptance inspection .33
5.17 Drawing of samples .33
5.18 Acceptability of lots .34
6 100 % inspection .34
6.1 Application of the method .34

62058-11 © IEC:2008 – 3 –
6.2 Lot sizes and acceptance numbers.34
6.3 Acceptance and non-acceptance .35
7 Lot-by-lot inspection by attributes .35
7.1 Application of the method .35
7.2 Drawing of samples .36
7.3 Inspection level .36
7.4 Sampling plans.36
7.4.1 Obtaining a sampling plan .36
7.4.2 Single sampling plans.36
7.4.3 Double sampling plans .39
7.4.4 Determination of acceptability.40
7.5 Normal, tightened and reduced inspection (see also 5.12).41
7.5.1 Start and continuation of inspection.41
7.5.2 Normal to tightened .41
7.5.3 Tightened to normal.42
7.5.4 Normal to reduced .42
7.5.5 Reduced to normal .43
7.5.6 Discontinuation and resumption of inspection .43
7.6 Operating characteristic (OC) curves.43
7.7 Process average .46
7.8 Average outgoing quality (AOQ) .46
7.9 Average outgoing quality limit (AOQL).46
7.10 Consumer’s risk (CR) .47
7.11 Producer’s risk (PR) .49
8 Isolated lot inspection.50
8.1 Application of the method .50
8.2 Procedures specified.50
8.2.1 Procedure A .50
8.2.2 Procedure B .50
8.3 Limiting quality .50
8.4 Procedure A .50
8.5 Procedure B .53
8.6 Rules for acceptance and non-acceptance .55
9 Skip-lot inspection .55
9.1 Application of the method .55
9.2 Manufacturer qualification .56
9.3 Product qualification.56
9.4 Detailed procedures .57
10 Lot-by-lot inspection by variables .57
10.1 Application of the method .57
10.2 Choice between the “s” and the “σ” methods.57
10.3 Standard plans .58
10.4 Preliminary operations.58
10.5 Standard multivariate “s” method procedures for independent quality
characteristics with combined control .
10.5.1 General methodology .58
10.5.2 Sampling plans.59
10.5.3 Description of the procedure.60
10.5.4 Simplified exact formula for the “s” method with sample size 4 .61

– 4 – 62058-11 © IEC:2008
10.5.5 Approximate procedure for the “s” method for n > 5 .61
10.6 Standard multivariate “σ” method procedures for independent quality
characteristics with combined control .64
10.6.1 General methodology .64
10.6.2 Sampling plans.65
10.6.3 Description of the procedure.65
10.7 Procedure during continuing inspection .66
10.8 Normality and outliers.66
10.8.1 Normality.66
10.8.2 Outliers .66
10.9 Records .66
10.9.1 Control charts.66
10.9.2 Lots that are not accepted .66
10.10 Normal, tightened and reduced inspection (see also 5.12) .66
10.11 Discontinuation and resumption of inspection .67
10.12 Switching between the “s” and “σ” methods .68
10.12.1 Estimating the process standard deviation .68
10.12.2 State of statistical control .68
10.12.3 Switching from the “s” method to the “σ” method .68
10.12.4 Switching from the “σ” method to the “s” method .69
10.13 Consumer protection .69
10.14 Operating characteristic curves .69
10.15 Consumer’s risk (CR) .72
10.16 Producer’ risk (PR) .74
Annex A (normative) Random numbers.76
Annex B (normative) Procedure for obtaining s or σ .79
Bibliography.80

Figure 1 – Selection procedure of sampling schemes and plans .
Figure 2 – Outline of switching rules .32
Figure 3 – OC curves for AQL = 1,0, single sampling plans, normal inspection .44
Figure 4 – OC curves for AQL = 1,0, single sampling plans, tightened inspection .44
Figure 5 – OC curves for single sampling plans, Ac=0 .45
Figure 6 – Operating characteristic curves for single sampling plans for non-critical
nonconformities, procedure B .54
Figure 7 – OC curves for normal inspection, AQL = 1,0.69
Figure 8 – OC curves for tightened inspection, AQL = 1,0.70
Figure 9 – OC curves for reduced inspection, AQL = 1,0.71

Table 1 – Acceptance number Ac for 100 % inspection .34
Table 2 – Single sampling plans for normal, tightened and reduced inspection, AQL = 1,0.37
Table 3 – Example with lot size = 80, inspection level II.37
Table 4 – Example with lot size = 400, inspection level II.38
Table 5 – Example with lot size = 800, inspection level III.38
Table 6 – Single sampling plans for critical nonconformities Ac = 0.39
Table 7 – Double sampling plans for normal, tightened and reduced inspection, AQL = 1,0 .40

62058-11 © IEC:2008 – 5 –
Table 8 – Calculation of switching scores .43
Table 9 – Tabulated values of OC curves for single sampling, AQL = 1,0 plans .45
Table 10 – Tabulated values of OC curves for single sampling, normal inspection,
accept zero sampling plans.46
Table 11 – Average Outgoing Quality Limit (AOQL) at AQL = 1,0.47
Table 12 – Average Outgoing Quality Limit (AOQL) for Ac = 0 sampling plans, normal
inspection .47
Table 13 – Consumer’s risk quality (CRQ): AQL = 1,0 plans .48
Table 14 – Consumer’s risk quality (CRQ): Accept zero plans.48
Table 15 – Producer’s risk (PR): AQL = 1,0 .49
Table 16 – Producer’s risk (PR): Accept zero plans .49
Table 17 – Sampling plans for non-critical nonconformities, procedure A, LQ = 5,0 .51
Table 18 – Sampling plans for critical nonconformities, procedure A.52
Table 19 – Probability of acceptance for accept zero plans.52
Table 20 – Single sampling plans for non-critical nonconformities, procedure B, LQ = 5,0 .54
Table 21 – Equivalent sample sizes for single and double sampling.55
Table 22 – Equivalent acceptance numbers for single and double sampling.55
Table 23 – Sample sizes for the “s” method and the “σ” method with AQL = 1,0 .58
Table 24 – Sampling plans for the “s” method .60
Table 25 – Values of a .62
n
Table 26 – Sampling plans for the “σ” method.65
Table 27 – Supplementary acceptability constants for qualifying towards reduced
inspection .67
Table 28 – Values of c for upper control limit on the sample standard deviation .68
U
Table 29 – Tabulated values of OC curves for normal inspection, AQL = 1,0 .70
Table 30 – Tabulated values of OC curves for tightened inspection, AQL = 1,0.71
Table 31 – Tabulated values of OC curves for reduced inspection, AQL = 1,0.72
Table 32 – Consumer’s risk quality (CRQ): “s” method .73
Table 33 – Consumer’s risk quality (CRQ): “σ” method .73
Table 34 – Producer’s risk (PR): “s” method.74
Table 35 – Producer’s risk (PR): “σ” method .74
Table A.1 – Random numbers.76

– 6 – 62058-11 © IEC:2008
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICITY METERING EQUIPMENT (AC) –
ACCEPTANCE INSPECTION –
Part 11: General acceptance inspection methods

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International Standard IEC 62058-11 has been prepared by IEC technical comm
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