SIST EN IEC 61000-4-20:2022

Electromagnetic compatibility (EMC) - Part 4-20: Testing and measurement techniques - Emission and immunity testing in transverse electromagnetic (TEM) waveguides

IEC 61000-4-20:2022 focuses on emission and immunity test methods for electrical and electronic equipment using various types of transverse electromagnetic (TEM) waveguides. These types include open structures (for example striplines and electromagnetic pulse simulators) and closed structures (for example TEM cells). These structures can be further classified as one-port, two-port, or multi-port TEM waveguides. The frequency range depends on the specific testing requirements and the specific TEM waveguide type. The object of this document is to describe

   
• TEM waveguide characteristics, including typical frequency ranges and equipment-under-test (EUT) size limitations;

   
• TEM waveguide validation methods for electromagnetic compatibility (EMC) tests;

   
• the EUT (i.e. EUT cabinet and cabling) definition;

   
• test set-ups, procedures, and requirements for radiated emission measurements in TEM waveguides; and

   
• test set-ups, procedures, and requirements for radiated immunity testing in TEM waveguides.

NOTE Test methods are defined in this document to measure the effects of electromagnetic radiation on equipment and the electromagnetic emissions from the equipment concerned. The simulation and measurement of electromagnetic radiation is not adequately exact for the quantitative determination of effects for all end-use installations. The test methods defined are structured for a primary objective of establishing adequate reproducibility of results at various test facilities for qualitative analysis of effects.
This document does not intend to specify the tests to be applied to any particular apparatus or system(s). The main intention of this document is to provide a general basic reference for all interested product committees of the IEC. For radiated emission measurements, product committees select emission limits and measurement methods in consultation with CISPR standards. For radiated immunity testing, product committees remain responsible for the appropriate choice of immunity tests and immunity test limits to be applied to equipment within their scope. This document describes test methods that are separate from those of IEC 61000‑4‑3.
This third edition cancels and replaces the second edition published in 2010. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:

   
1. provide information on the testing of large EUTs (including cables);

   
2. apply the work on measurement uncertainties by adapting the work completed in CISPR and TC 77 (for emissions and immunity);

   
3. update the validation procedure for the test volume regarding field uniformity and TEM mode verification;

   
4. provide information concerning two-port and four-port TEM waveguides;

   
5. add a new informative annex (Annex I) dealing with transient TEM waveguide characterization; and

   
6. add information dealing with dielectric test stands for EUTs.

Elektromagnetische Verträglichkeit (EMV) - Teil 4-20: Prüf- und Messverfahren - Messung der Störaussendung und Prüfung der Störfestigkeit in transversal-elektromagnetischen (TEM-)Wellenleitern

Compatibilité électromagnétique (CEM) - Partie 4-20: Techniques d'essai et de mesure - Essais d'émission et d'immunité dans les guides d'onde TEM

IEC 61000-4-20:2022 concerne les méthodes d’essai d’émission et d’immunité pour les matériels électriques et électroniques qui utilisent différents types de guides d’onde transverses électromagnétiques (TEM). Ces types comprennent des structures ouvertes (par exemple, des lignes ouvertes et des simulateurs d’impulsion électromagnétique), et des structures fermées (par exemple, des cellules TEM), qui peuvent être elles-mêmes classées en guides d’onde TEM à un accès, à deux accès, ou à accès multiples. La plage de fréquences dépend des exigences d’essai spécifiques et du type spécifique de guide d’onde TEM.
L’objet du présent document est de décrire

   
• les caractéristiques des guides d’onde TEM, y compris les plages de fréquences types et les limites de tailles des équipements en essai (EUT);

   
• les méthodes de validation des guides d’onde TEM pour les essais de compatibilité électromagnétique CEM;

   
• la définition de l'EUT (c’est-à-dire l’armoire et le câblage de l'EUT);

   
• les montages d’essai, les procédures et les exigences relatives aux mesurages d’émissions rayonnées dans les guides d’onde TEM; et

   
• les montages d'essai, les procédures et les exigences pour les essais d’immunité rayonnée dans les guides d’onde TEM.

NOTE Dans le présent document, les méthodes d’essai sont définies afin de mesurer les effets des rayonnements électromagnétiques sur les matériels et les émissions électromagnétiques des matériels concernés. La simulation et le mesurage des rayonnements électromagnétiques ne sont pas suffisamment exacts pour une détermination quantitative des effets sur toutes les installations d'utilisation finale. Les méthodes d’essai définies sont structurées avec l’objectif premier d'établir une reproductibilité adéquate des résultats dans différentes installations d’essai pour des analyses qualitatives des effets.
Le présent document ne vise pas à spécifier les essais à appliquer à des appareils ou à un ou des systèmes particuliers. Le but principal présent document est de donner une référence de base d'ordre général à tous les comités de produits IEC concernés. Pour les mesurages d’émission rayonnée, les comités de produits sélectionnent des limites d’émission et des méthodes de mesure en consultation avec les normes CISPR. Pour les essais d’immunité rayonnée, les comités de produits restent responsables du choix approprié des essais d’immunité et des limites qui y sont associées, à appliquer aux matériels qui relèvent de leur domaine d’application. Le présent document décrit des méthodes d'essai qui sont indépendantes de celles de l'IEC 61000-4-3 [34].
CEM conformément au Guide IEC 107.
Cette troisième édition annule et remplace la deuxième édition parue en 2010. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) fournir des informations relatives aux essais d'EUT volumineux (y compris les câbles);
b) appliquer les travaux sur les incertitudes de mesure par adaptation des travaux réalisés par le CISPR et le CE 77 (pour les émissions et l'immunité);
c) mettre à jour la procédure de validation pour le volume d'essai en ce qui concerne la vérification de l'uniformité du champ et du mode TEM;
d) fournir des informations relatives aux guides d'onde TEM à deux accès et à quatre accès;
e) ajouter une nouvelle annexe informative (Annex I) qui traite de la caractérisation d

Elektromagnetna združljivost (EMC) - 4-20. del: Preskusne in merilne tehnike - Preskušanje oddajanja in odpornosti v prečnih elektromagnetnih (TEM) valovodih

Ta del standarda IEC 61000 se osredotoča na preskusne metode glede oddajanja in odpornosti za električno in elektronsko opremo z uporabo različnih tipov prečnih elektromagnetnih (TEM) valovodov. Ti tipi vključujejo odprte strukture (na primer ploščate valovode in simulatorje elektromagnetnih pulzov) ter zaprte strukture (na primer TEM-celice). Te strukture se lahko nadalje klasificirajo kot eno-, dvo- ali več-kanalni TEM-valovodi. Frekvenčni razpon je odvisen od določenih zahtev za preskušanje in določenega TEM-valovoda. Namen tega standarda je opisati: – značilnosti TEM-valovoda, vključno z tipičnimi frekvenčnimi razponi in omejitvami velikosti preskušane opreme (EUT); – validacijske metode za preskuse elektromagnetne združljivosti (EMC) TEM-valovodov; – opredelitev preskušane opreme (preskušanega ohišja in okabljenja); – preskusne postavitve, postopke in zahteve za meritve emisij sevanja pri TEM-valovodih; ter – preskusne postavitve, postopke in zahteve za preskušanje TEM-valovodov glede odpornosti proti sevanju. OPOMBA: Preskusne metode so v tem dokumentu opredeljene za merjenje učinkov elektromagnetnega sevanja na opremo in elektromagnetnih emisij iz zadevne opreme. Simulacija in merjenje elektromagnetnega sevanja nista dovolj natančna za kvantitativno določevanje učinkov za vse končne uporabe inštalacij. Opredeljene preskusne metode so strukturirane za primarni cilj ugotavljanja zadostne ponovljivosti rezultatov v različnih preskuševalnih laboratorijih za kvalitativno analizo učinkov. Ta dokument ni namenjen določevanju preskusov, predvidenih za uporabo pri kateri koli določeni napravi ali sistemu oziroma sistemih. Glavni namen tega dokumenta je zagotoviti splošno in osnovno referenco za vse zainteresirane odbore za izdelke v okviru Mednarodne elektrotehniške komisije (IEC). Za meritve emisij sevanja morajo odbori za izdelke izbrati meje emisij in merilne metode ob upoštevanju napotkov standardov CISPR. Odbori ostajajo odgovorni za primerno izbiro preskusov odpornosti in meja preskusov pri preskušanju odpornosti proti sevanju, ki se uporabijo za opremo v okviru njihovega področja uporabe. Ta dokument opisuje preskusne metode, ki so ločene od tistih iz standarda IEC 61000 4 3 [34].1

General Information

• Status: Published
• Publication Date: 15-Jun-2022
• ICS: 33.100.10 - Emission
• ICS: 33.100.20 - Immunity
• Technical Committee: EMC - Electromagnetic compatibility
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 02-Jun-2022
• Due Date: 07-Aug-2022
• Completion Date: 16-Jun-2022
• Directive: 2014/30/EU - Directive 2014/30/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 electromagnetic compatibility (recast)
• Mandate: M/490 - Standardisation mandate to the European Standardisation Organisations (ESOs) to support European Smart Grid deployment
• Ref Project: EN IEC 61000-4-20:2022 - Electromagnetic compatibility (EMC) - Part 4-20: Testing and measurement techniques - Emission and immunity testing in transverse electromagnetic (TEM) waveguides

Relations

• Replaces: SIST EN 61000-4-20:2011 - Electromagnetic compatibility (EMC) - Part 4-20: Testing and measurement techniques - Emission and immunity testing in transverse electromagnetic (TEM) waveguides (IEC 61000-4-20:2010)
• Effective Date: 01-Jul-2022

Overview

EN IEC 61000-4-20:2022 - Electromagnetic compatibility (EMC) - Part 4-20 - defines testing and measurement techniques for emission and immunity testing in transverse electromagnetic (TEM) waveguides. The standard covers both open structures (e.g., striplines, EMP simulators) and closed structures (e.g., TEM cells) and addresses one‑port, two‑port and multi‑port TEM waveguide configurations. It provides requirements for TEM waveguide characteristics, usable test volume and EUT size limitations, validation methods, test set‑ups and procedures for radiated emission and radiated immunity testing.

Key topics and requirements

• TEM waveguide characteristics: definitions of open vs closed waveguides, typical usable frequency ranges (dependent on waveguide type) and maximum EUT dimensions relative to test volume.
• Validation and calibration: methods to validate usable test volume, field uniformity checks and TEM‑mode verification to ensure reproducible EMC results across test facilities.
• Emission measurements: procedures to correlate voltages measured in TEM waveguides to equivalent E‑field strengths, correction factors, reference sources and small/large EUT arrangements.
• Immunity testing: test set‑ups, field uniformity area calibration, test levels and wiring/equipment arrangements for radiated immunity in TEM waveguides.
• Advanced topics added in 2022 edition: guidance for testing large EUTs (including cabling), application of measurement uncertainty methods adapted from CISPR and TC 77, updated validation for test volumes, coverage of two‑port and four‑port TEM waveguides, transient/HEMP testing information, and dielectric test‑stand guidance.
• Reporting and reproducibility: standardized test report content and emphasis on qualitative reproducibility rather than exact prediction for every end‑use installation.

Applications and who uses it

• EMC test laboratories performing controlled radiated emission and immunity tests using TEM cells, striplines or EMP simulators.
• Product manufacturers and design engineers validating EMC behavior of electronic equipment, enclosures and cabling in early design and compliance phases.
• Compliance and certification teams preparing evidence for regulatory or sector‑specific EMC requirements.
• Standards and product committees using the methods as a baseline to define product‑specific emission limits and immunity levels.
  Practical uses include pre‑compliance emission screening, radiated immunity susceptibility testing, HEMP/transient investigations and correlation of waveguide measurements to free‑space field levels.

Related standards

• IEC 61000‑4‑3 (separate radiated immunity methods)
• CISPR series (measurement apparatus and emission limits, e.g., CISPR 16)
• Relevant IEC/CENELEC harmonized standards referenced in EN IEC 61000‑4‑20 for probe calibration, measurement uncertainty and test apparatus.

Keywords: EN IEC 61000-4-20:2022, TEM waveguide, TEM cell, EMC testing, radiated emission, radiated immunity, TEM waveguide validation, EMC test methods.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2022
Nadomešča:
SIST EN 61000-4-20:2011
Elektromagnetna združljivost (EMC) - 4-20. del: Preskusne in merilne tehnike -
Preskušanje oddajanja in odpornosti v prečnih elektromagnetnih (TEM) valovodih
Electromagnetic compatibility (EMC) - Part 4-20: Testing and measurement techniques -
Emission and immunity testing in transverse electromagnetic (TEM) waveguides
Elektromagnetische Verträglichkeit (EMV) - Teil 4-20: Prüf- und Messverfahren -
Messung der Störaussendung und Prüfung der Störfestigkeit in transversal-
elektromagnetischen (TEM-)Wellenleitern
Compatibilité électromagnétique (CEM) - Partie 4-20: Techniques d'essai et de mesure -
Essais d'émission et d'immunité dans les guides d'onde TEM
Ta slovenski standard je istoveten z: EN IEC 61000-4-20:2022
ICS:
33.100.10 Emisija Emission
33.100.20 Imunost Immunity
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 61000-4-20

NORME EUROPÉENNE
EUROPÄISCHE NORM April 2022
ICS 33.100.10; 33.100.20 Supersedes EN 61000-4-20:2010 and all of its
amendments and corrigenda (if any)
English Version
Electromagnetic compatibility (EMC) - Part 4-20: Testing and
measurement techniques - Emission and immunity testing in
transverse electromagnetic (TEM) waveguides
(IEC 61000-4-20:2022)
Compatibilité électromagnétique (CEM) - Partie 4-20: Elektromagnetische Verträglichkeit (EMV) - Teil 4-20: Prüf-
Techniques d'essai et de mesure - Essais d'émission et und Messverfahren - Messung der Störaussendung und
d'immunité dans les guides d'onde TEM Prüfung der Störfestigkeit in transversal-
(IEC 61000-4-20:2022) elektromagnetischen (TEM-)Wellenleitern
(IEC 61000-4-20:2022)
This European Standard was approved by CENELEC on 2022-03-25. 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 CEN-CENELEC
Management Centre 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 CEN-CENELEC Management Centre 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, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61000-4-20:2022 E

European foreword
The text of document 77B/853/FDIS, future edition 3 of IEC 61000-4-20, prepared by SC 77B "High
frequency phenomena" of IEC/TC 77 "Electromagnetic compatibility" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN IEC 61000-4-20:2022.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2022-12-25
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2025-03-25
document have to be withdrawn
This document supersedes EN 61000-4-20:2010 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a Standardization Request given to CENELEC by the
European Commission and the European Free Trade Association.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61000-4-20:2022 was approved by CENELEC as a
European Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60068-1 NOTE Harmonized as EN 60068-1
IEC 60118-13 NOTE Harmonized as EN IEC 60118-13
IEC 61967-2 NOTE Harmonized as EN 61967-2
IEC 62132-2 NOTE Harmonized as EN 62132-2
CISPR 25 NOTE Harmonized as EN IEC 55025
CISPR 14 (series) NOTE Harmonized as EN IEC 55014-2 (series)
CISPR 16-4-2 NOTE Harmonized as EN 55016-4-2
IEC 61000-2-9 NOTE Harmonized as EN 61000-2-9
IEC 61000-4-3 NOTE Harmonized as EN IEC 61000-4-3
CISPR 16-2-3:2016 NOTE Harmonized as EN 55016-2-3:2017 (not modified)
CISPR 32 NOTE Harmonized as EN 55032
CISPR 20:2006 NOTE Harmonized as EN 55020:2007 (not modified) +A11:2011
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 1 Where an International Publication has been modified by common modifications, indicated by (mod), the
relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-161 - International Electrotechnical Vocabulary - -
(IEV) - Part 161: Electromagnetic
compatibility
CISPR 16-1-1 - Specification for radio disturbance and EN IEC 55016-1-1 -
immunity measuring apparatus and
methods - Part 1-1: Radio disturbance and
immunity measuring apparatus -
Measuring apparatus
CISPR 16-1-4 - Specification for radio disturbance and EN IEC 55016-1-4 -
immunity measuring apparatus and
methods - Part 1-4: Radio disturbance and
immunity measuring apparatus - Antennas
and test sites for radiated disturbance
measurements
IEC 61000-4-20 ®
Edition 3.0 2022-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC EMC PUBLICATION
PUBLICATION FONDAMENTALE EN CEM

Electromagnetic compatibility (EMC) –

Part 4-20: Testing and measurement techniques – Emission and immunity

testing in transverse electromagnetic (TEM) waveguides

Compatibilité électromagnétique (CEM) –

Partie 4-20: Techniques d’essai et de mesure – Essais d’émission et d’immunité

dans les guides d’onde TEM
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.100.10; 33.100.20 ISBN 978-2-8322-1083-0

– 2 – IEC 61000-4-20:2022 © IEC 2022
CONTENTS
FOREWORD . 7
INTRODUCTION . 9
1 Scope . 10
2 Normative references . 11
3 Terms, definitions and abbreviated terms . 11
3.1 Terms and definitions . 11
3.2 Abbreviated terms . 14
4 General . 15
5 TEM waveguide requirements . 15
5.1 General . 15
5.2 General requirements for the use of TEM waveguides . 16
5.2.1 Test volume and maximum EUT size . 16
5.2.2 Validation of usable test volume . 16
5.3 Special requirements and recommendations for certain types of TEM
waveguides . 23
5.3.1 Set-up of open TEM waveguides . 23
5.3.2 Alternative TEM mode verification for a two-port TEM waveguide . 23
5.3.3 TEM mode generation for a four-port TEM waveguide . 23
5.4 Figures for Clause 5 . 24
6 Overview of EUT types . 26
6.1 General . 26
6.2 Small EUT . 26
6.3 Large EUT . 26
7 Laboratory test conditions. 26
7.1 General . 26
7.2 Climatic conditions . 26
7.3 Electromagnetic conditions . 26
8 Evaluation and reporting of test results . 27
Annex A (normative) Emission measurements in TEM waveguides . 28
A.1 Overview. 28
A.2 Test equipment . 28
A.3 Correlating TEM waveguide voltages to electric field strength data . 28
A.3.1 General . 28
A.3.2 Correlation algorithms . 29
A.4 Emission measurement correction factors . 33
A.4.1 Reference emission sources . 33
A.4.2 Arrangement of small EUTs . 34
A.4.3 Calculation of the small EUT correction factor . 34
A.5 Emission measurement procedures in TEM waveguides . 37
A.5.1 EUT types. 37
A.5.2 EUT arrangement . 37
A.6 Test report . 38
A.7 Figures for Annex A . 39
Annex B (normative) Immunity testing in TEM waveguides . 44
B.1 Overview. 44
B.2 Test equipment . 44

IEC 61000-4-20:2022 © IEC 2022 – 3 –
B.2.1 General . 44
B.2.2 Description of the test facility . 44
B.3 Field uniformity area calibration . 45
B.4 Test levels . 45
B.5 Test set-up . 45
B.5.1 Arrangement of table-top equipment . 45
B.5.2 Arrangement of floor-standing equipment . 46
B.5.3 Arrangement of wiring . 46
B.6 Test procedures . 46
B.7 Test results and test report . 46
B.8 Figures for Annex B . 47
Annex C (normative) HEMP transient testing in TEM waveguides . 49
C.1 Overview. 49
C.2 Immunity tests . 49
C.2.1 General . 49
C.2.2 Radiated test facilities . 50
C.2.3 Frequency domain spectrum requirements . 51
C.3 Test equipment . 51
C.4 Test set-up . 52
C.5 Test procedure . 52
C.5.1 General . 52
C.5.2 Severity level and test exposures . 53
C.5.3 Test procedure . 53
C.5.4 Test execution . 54
C.5.5 Execution of the radiated immunity test . 54
C.6 Figure for Annex C . 55
Annex D (informative) TEM waveguide characterization . 56
D.1 Overview. 56
D.2 Distinction between wave impedance and characteristic impedance. 56
D.3 TEM wave . 57
D.3.1 General . 57
D.3.2 Free-space TEM mode . 57
D.3.3 Waveguides . 57
D.4 Wave propagation . 58
D.4.1 General . 58
D.4.2 Spherical propagation . 58
D.4.3 Plane wave propagation in free space . 58
D.4.4 Velocity of propagation . 58
D.5 Polarization . 58
D.6 Types of TEM waveguides . 59
D.6.1 General . 59
D.6.2 Open TEM waveguides (striplines, etc.) . 60
D.6.3 Closed TEM waveguides (TEM cells) . 60
D.7 Frequency limitations . 60
D.8 Figures for Annex D . 61
Annex E (informative) Calibration method for E-field probes in TEM waveguides . 69
E.1 Overview. 69
E.2 Probe calibration requirements . 69
E.2.1 General . 69

– 4 – IEC 61000-4-20:2022 © IEC 2022
E.2.2 Calibration frequency range . 69
E.2.3 Calibration volume . 70
E.2.4 Probe dimensions . 70
E.2.5 Perturbations of TEM waveguide fields due to the probe . 70
E.2.6 Frequency steps . 71
E.2.7 Field strength . 71
E.3 Requirements for calibration instrumentation . 71
E.3.1 Specifications of TEM waveguide . 71
E.3.2 Harmonics and spurious signals . 72
E.3.3 Probe fixture . 72
E.3.4 Measuring net power to a transmitting device using directional couplers . 72
E.4 E-field probe calibration . 73
E.4.1 Calibration methods . 73
E.4.2 Calibration procedure using a two-port TEM waveguide . 73
E.4.3 Calibration procedure using one-port TEM waveguide . 74
E.5 Figures for Annex E . 77
Annex F (informative) Instrumentation uncertainty of emission measurement results . 79
F.1 Radiated disturbance measurements using a TEM waveguide . 79
F.1.1 Measurand for radiated disturbance measurements using a TEM
waveguide . 79
F.1.2 Symbols of input quantities common to all disturbance measurements . 79
F.1.3 Symbols of input quantities specific to TEM waveguide measurements . 79
F.2 Input quantities to be considered for radiated disturbance measurements
using a TEM waveguide . 79
F.3 Uncertainty budget and rationale for the input quantities for radiated
disturbance measurements using a TEM waveguide . 80
F.3.1 Uncertainty budget for radiated disturbance measurements using a TEM

waveguide . 80
F.3.2 Rationale for the estimates of input quantities for radiated disturbance
measurements using a TEM waveguide . 81
F.4 Figures for Annex F . 87
Annex G (informative) Measurement uncertainty of immunity testing due to test
instrumentation . 89
G.1 General symbols . 89
G.2 Symbol and definition of the measurand . 89
G.3 Symbols for input quantities . 89
G.4 Example: Uncertainty budget for immunity test . 89
G.5 Rationale for the estimates of input quantities . 90
Annex H (informative) Correlation of emission and immunity limits between EMC test
facilities . 93
H.1 Overview. 93
H.2 Dipole in free space (representing FAR set-up) . 93
H.3 Dipole in half space (representing OATS or SAC set-up). 95
H.4 Dipole in a TEM-mode transmission line . 96
H.5 Dipole in a reverberation chamber . 97
H.6 Correlation . 98
H.7 Example of emission limits . 99
H.8 Figures for Annex H . 100
Annex I (informative) TEM waveguide transient characterization . 103
I.1 Overview. 103

IEC 61000-4-20:2022 © IEC 2022 – 5 –
I.2 Test equipment . 103
I.3 Test set-up . 103
I.4 TEM waveguide characterization by correlation . 104
I.5 Quantification of the Pcc . 105
I.6 Performable transient test signals . 105
I.7 Figures for Annex I . 106
Bibliography . 108

Figure 1 – Flowchart of TEM mode and field uniformity verification procedure with the
“constant forward power” method (see 5.2.2.4.1) . 24
Figure 2 – Flowchart of TEM mode and field uniformity verification procedure with the

“constant field strength” method (see 5.2.2.4.2) . 25
Figure A.1 – Routing the exit cable to the corner at the ortho-angle and the lower edge
of the test volume in a TEM waveguide (see A.5.2) . 39
Figure A.2 – Basic ortho-axis EUT positioner or manipulator (see 3.1.13, A.4.2,
A.5.1.2, A.5.2) . 40
Figure A.3 – Die pattern and axis alignment for an EUT [26] (see A.3.2.3.2) . 41
Figure A.4 – Non-redundant twelve-face and axis orientations for a typical EUT [26]
(see A.3.2.3.2) . 42
Figure A.5 – Open-area test site (OATS) emission measurements geometry (see
A.3.2.4) . 43
Figure B.1 – Example of test set-up for single-polarization TEM waveguide
(see Clause B.5) . 47
Figure B.2 – Uniform area calibration points in a TEM waveguide (see Clause B.3) . 48
Figure C.1 – Pulse waveform frequency domain spectral magnitude between 100 kHz

and 300 MHz (see C.2.1) . 55
Figure D.1 – Simple waveguide (no TEM mode) (see D.3.3) . 61
Figure D.2 – Example of waveguides supporting TEM-mode propagation (see D.3.3) . 61
Figure D.3 – E-field polarization vector (see Clause D.5) . 61
Figure D.4 – Simple transmission line model for TEM mode propagation (see D.6.1) . 62
Figure D.5 – One- and two-port TEM waveguide concepts (see D.6.1) . 62
Figure D.6 – Operation of four-port TEM waveguides (see D.6.1) . 62
Figure D.7 – Two-port TEM cell (symmetric septum) (see D.6.1 and D.6.3) . 63
Figure D.8 – One-port TEM cell (asymmetric septum) (see D.6.1 and D.6.3) . 64
Figure D.9 – Stripline (two plates) (see D.6.1 and D.6.2) . 66
Figure D.10 – Stripline (four plates, balanced feed) (see D.6.1) . 67
Figure D.11 – Four-port TEM waveguide (symmetric parallel septa) (see D.6.1 and
D.6.3) . 68
Figure E.1 – Example of test points for calibration volume validation (see E.2.3) . 77
Figure E.2 – Set-up for validation of probe perturbation (see E.2.5) . 77
Figure E.3 – Set-up for measuring net power to a transmitting device (not to scale)
(see E.3.4) . 77
Figure E.4 – Example set-up for E-field probe calibration with two-port TEM waveguide

(see E.4.2) . 78
Figure E.5 – Example set-up for E-field probe calibration with one-port TEM waveguide
and alternative method (see E.4.3.2) . 78
Figure E.6 – Equivalent circuit of monopole antenna and measuring apparatus (see
E.4.3.3) . 78

– 6 – IEC 61000-4-20:2022 © IEC 2022
Figure F.1 – Deviation of the QP detector level indication from the signal level at
receiver input for two cases, a sine-wave signal and an impulsive signal with a pulse
repetition frequency of 100 Hz . 87
Figure F.2 – 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 with a pulse
repetition frequency of 100 Hz . 88
Figure H.1 – Representation of a short centre-fed dipole and a more general source

representing an EUT (see Clause H.2) . 100
Figure H.2 – Vertical source and receiving dipoles located over a perfectly-conducting
ground plane of infinite extent (see Clause H.3) . 100
Figure H.3 – Two types of TEM cells with a vertically polarized dipole source and the
source to receive port geometry defined (see Clause H.4) . 101
Figure H.4 – Reverberation chamber with a source dipole, a stirrer to randomize the

fields, and a general receive antenna (see Clause H.5) . 101
Figure H.5 – TEM waveguide Class A and Class B emission limits correlated from
CISPR 32 [68] (see Clause H.7) . 102
Figure I.1 – Test set-up . 106
Figure I.2 – Signal windowing . 107
Figure I.3 – Example of a heatmap – Pcc for a test point in the uniform area . 107

Table 1 – Values k for expanded uncertainty with normal distribution . 18
Table B.1 – Uniform area calibration points . 45
Table B.2 – Test levels . 45
Table C.1 – Radiated immunity test levels defined for this document . 50
Table E.1 – Calibration frequencies . 71
Table E.2 – Calibration field strength level . 71
Table F.1 – Uncertainty budget for radiated disturbance measurement results using a
TEM waveguide from 30 MHz to 1 000 MHz (example) . 80
Table F.2 – Uncertainty budget for radiated disturbance measurement results using a

TEM waveguide from 1 GHz to 6 GHz (example) . 81
Table F.3 – Values of S for 30 MHz to 1 000 MHz . 83
lim
Table F.4 – Values of S for 1 GHz to 6 GHz . 84
lim
Table G.1 – Example uncertainty budget of the immunity test level . 90
Table H.1 – Summary of the emission correlation parameters . 99

IEC 61000-4-20:2022 © IEC 2022 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 4-20: Testing and measurement techniques –
Emission and immunity testing in transverse
electromagnetic (TEM) waveguides

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
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Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61000-4-20 has been prepared by subcommittee 77B: High
frequency phenomena, of IEC technical committee 77: Electromagnetic compatibility, in
cooperation with CISPR (International Special Committee on Radio Interference)
subcommittee A: Radio-interference measurements and statistical methods.
It forms Part 4-20 of IEC 61000. It has the status of a basic EMC publication in accordance with
IEC Guide 107.
This third edition cancels and replaces the second edition published in 2010. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) provide information on the testing of large EUTs (including cables);

– 8 – IEC 61000-4-20:2022 © IEC 2022
b) apply the work on measurement uncertainties by adapting the work completed in CISPR and
TC 77 (for emissions and immunity);
c) update the validation procedure for the test volume regarding field uniformity and TEM mode
verification;
d) provide information concerning two-port and four-port TEM waveguides;
e) add a new informative annex (Annex I) dealing with transient TEM waveguide
characterization; and
f) add information dealing with dielectric test stands for EUTs.
The text of this International Standard is based on the following documents:
Draft Report on voting
77B/853/FDIS 77B/855/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts of the IEC 61000 series, published under the general title Electromagnetic
compatibility (EMC), can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates that it
contains colours which are considered to be useful for the correct understanding of its
contents. Users should therefore print this document using a colour printer.

IEC 61000-4-20:2022 © IEC 2022 – 9 –
INTRODUCTION
IEC 61000 is published in separate parts according to the following structure:
Part 1: General
General considerations (introduction, fundamental principles)
Definitions, terminology
Part 2: Environment
Description of the environment
Classification of the environment
Compatibility levels
Part 3: Limits
Emission limits
Immunity limits (in so far as they do not fall under the responsibility of the product
committees)
Part 4: Testing and measurement techniques
Measurement techniques
Testing techniques
Part 5: Installation and mitigation guidelines
Installation guidelines
Mitigation methods and devices
Part 6: Generic standards
Part 9: Miscellaneous
Each part is further subdivided into several parts, published either as International Standards,
Technical Specifications or Technical Reports, some of which have already been published as
sections. Others are and will be published with the part number followed by a dash and a second
number identifying the subdivision (example: IEC 61000-6-1).
This part is an International Standard which gives emission, immunity and HEMP and IEMI
transient testing requirements.

– 10 – IEC 61000-4-20:2022 © IEC 2022
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 4-20: Testing and measurement techniques –
Emission and immunity testing in transverse
electromagnetic (TEM) waveguides

1 Scope
This part of IEC 61000 focuses on emission and immunity test methods for electrical and
electronic equipment using various types of transverse electromagnetic (TEM) waveguides.
These types include open structures (for example striplines and electromagnetic pulse
simulators) and closed structures (for example TEM cells). These structures can be further
classified as one-port, two-port, or multi-port TEM waveguides. The frequency range depends
on the specific testing requirements and the specific TEM waveguide type.
The object of this document is to describe
– TEM waveguide characteristics, including typical frequency ranges and equipment-under-
test (EUT) size limitations;
– TEM waveguide validation methods for electromagnetic compatibility (EMC) tests;
– the EUT (i.e. EUT cabinet and cabling) definition;
– test set-ups, procedures, and requirements for radiated emission measurements in TEM
waveguides; and
– test set-ups, procedures, and requirements for radiated immunity testing in TEM
waveguides.
NOTE Test methods are defined in this document to measure the effects of electromagnetic radiation on equipment
and the electromagnetic emissions from the equipment concerned. The simulation and measurement of
electromagnetic radiation is not adequately exact for the quantitative determination of effects for all end-use
installations. The test methods defined are structured for a primary objective of establishing adequate reproducibility
of results at various test facilities for qualitative analysis of effects.
This document does not intend to specify the tests to be applied to any particular apparatus or
system(s). The main intention of this document is to provide a general basic reference for all
interested product committees of the IEC. For radiated emission measurements, product
committees select emission limits and measurement methods in consultation with CISPR
standards. For radiated immunity testing, product committees remain responsible for the
appropriate choice of immunity tests and immunity test limits to be applied to equipment within
their scope. This document describes test methods that are separate from those of
IEC 61000‑4‑3 [34].
___________
Numbers in square brackets refer to the Bibliography.
These other distinct test methods may be used when so specified by product committees, in consultation with CISPR
and TC 77.
IEC 61000-4-20:2022 © IEC 2022 – 11 –
2 Normative references
The followi
...