IEC TR 61000-1-6:2012

Electromagnetic compatibility (EMC) - Part 1-6: General - Guide to the assessment of measurement uncertainty

IEC/TR 61000-1-6:2012(E), which is a technical report, provides methods and background information for the assessment of measurement uncertainty. It gives guidance to cover general measurement uncertainty considerations within the IEC 61000 series. The objectives of this Technical Report are to give advice to technical committees, product committees and conformity assessment bodies on the development of measurement uncertainty budgets; to allow the comparison of these budgets between laboratories that have similar influence quantities; and to align the treatment of measurement uncertainty across the EMC committees of the IEC. It gives a description for:
- a method for the assessment of measurement uncertainty;
- mathematical formulas for probability density functions;
- analytical assessment of statistical evaluations;
- correction of measured data; and
- documentation. This Technical Report is not intended to summarize all measurement uncertainty influence quantities nor is it intended to define how measurement uncertainty is to be taken into account in determining compliance with an EMC requirement. The contents of the corrigendum of october 2014 have been included in this copy.

General Information

• Status: Published
• Publication Date: 08-Jul-2012
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 17.240 - Radiation measurements
• ICS: 33.100.01 - Electromagnetic compatibility in general
• Technical Committee: TC 77 - Electromagnetic compatibility
• Current Stage: PPUB - Publication issued
• Start Date: 15-Sep-2012
• Completion Date: 09-Jul-2012

Relations

• Corrected By: IEC TR 61000-1-6:2012/COR1:2014 - Corrigendum 1 - Electromagnetic compatibility (EMC) - Part 1-6: General - Guide to the assessment of measurement uncertainty
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC/TR 61000-1-6 ®
Edition 1.0 2012-07
TECHNICAL
REPORT
colour
inside
BASIC EMC PUBLICATION
Electromagnetic compatibility (EMC) –
Part 1-6: General – Guide to the assessment of measurement uncertainty

IEC/TR 61000-1-6:2012(E)
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IEC/TR 61000-1-6 ®
Edition 1.0 2012-07
TECHNICAL
REPORT
colour
inside
BASIC EMC PUBLICATION
Electromagnetic compatibility (EMC) –

Part 1-6: General – Guide to the assessment of measurement uncertainty

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XB
ICS 33.100 ISBN 978-2-83220-204-3

– 2 – TR 61000-1-6 © IEC:2012(E)
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, symbols and abbreviations . 8
3.1 Terms and definitions . 8
3.2 Symbols . 14
3.3 Abbreviations . 15
4 General . 16
4.1 Overview . 16
4.2 Classification of uncertainty contributions . 16
4.3 Limitations of the GUM . 17
4.4 Principles . 18
5 Measurement uncertainty budget development . 20
5.1 Basic steps . 20
5.2 Probability density functions . 24
5.2.1 Rectangular . 24
5.2.2 Triangular . 26
5.2.3 Gaussian . 28
5.2.4 U-Shape . 32
5.3 Concept of Type A and Type B evaluation of uncertainty . 35
5.3.1 General considerations . 35
5.3.2 Type A evaluation of standard uncertainty . 36
5.3.3 Type B evaluation of standard uncertainty . 40
5.4 Sampling statistics . 42
5.4.1 General considerations . 42
5.4.2 Sample mean and sample standard deviation . 42
5.4.3 Sample coefficient of variation . 43
5.4.4 Limits of sample-statistical confidence intervals . 43
5.4.5 Sampling distribution and sampling statistics of mean value . 44
5.4.6 Sampling distribution and sampling statistics of standard deviation . 47
5.5 Conversion from linear quantities to decibel and vice versa . 49
5.5.1 General considerations . 49
5.5.2 Normally distributed fluctuations . 49
5.5.3 Uniformly distributed fluctuations . 52
6 Applicability of measurement uncertainty . 52
7 Documentation of measurement uncertainty calculation . 56
Annex A (informative) Example of MU assessment for emission measurements . 57
Annex B (informative) Example of MU assessment for an immunity test level setting . 64
Bibliography . 67

Figure 1 – Classification of uncertainty components associated with the experimental
evaluation of uncertainty in EMC testing and measurement . 16

TR 61000-1-6 © IEC:2012(E) – 3 –
Figure 2 – Classification of uncertainty components associated with site uncertainty
(e.g. reverberation chambers) . 17
Figure 3 – Example of g(x’) . 19
Figure 4 – Impact of g(x) on interpretation of x’ . 19
Figure 5 – Estimate returned by the measurement system . 20
Figure 6 – Rectangular PDF . 25
Figure 7 – Triangular PDF . 27
Figure 8 – Normal PDF for standardized X . 29
Figure 9 – U-shaped PDF . 33
Figure 10 – Example of a circuit . 33
Figure 11 – Limits of 95 %, 99 % and 99,5 % confidence intervals for W as a function
of N for measurements using a rectilinear antenna or single-axis probe . 46
Figure 12 – Limits of 95 %, 99 % and 99,5 % confidence intervals for A as a function
of N for measurements using a rectilinear antenna or single-axis probe . 47
Figure 13 – 95 % confidence intervals for S as a function of N for measurements
X
using a single-axis detector . 48
Figure 14 – PDF of B for a Rayleigh distributed A at selected values of σ . 51
Figure 15 – Measurement uncertainty budget for a quantity to be realized in the test
laboratory . 53
Figure 16 – Relationship between measurement uncertainty budgets for a quantity to
be realized in the test laboratory and tolerances given for this quantity in the applicable
basic standard . 54
Figure 17 – Situations, where and how an instrument is suitable for tests and/or
measurements as specified in the applicable basic standard with tolerances . 55
Figure A.1 – Deviation of the peak detector level indication from the signal level at
receiver input for two cases, a sine-wave signal and an impulsive signal (PRF 100 Hz) . 60

Table 1 – Basic steps for calculating MU . 20
Table 2 – Expressions used to obtain standard uncertainty . 23
Table 3 – Examples of circuit parameters . 35
Table 4 – Values of the expansion coefficient η(ν) which transforms the standard
deviation to the Type A standard uncertainty . 39
Table A.1 – Radiated disturbance measurements from 1 GHz to 18 GHz in a FAR at a
distance of 3 m . 58
Table B.1 – Uncertainty budget of the radiated immunity test level (80 MHz –
1 000 MHz) . 65

– 4 – TR 61000-1-6 © IEC:2012(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 1-6: General –
Guide to the assessment of measurement uncertainty

FOREWORD
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