SIST EN IEC 61189-5-502:2021

Test methods for electrical materials, printed boards and other interconnection structures and assemblies - Part 5-502: General test methods for materials and assemblies - Surface insulation resistance (SIR) testing of assemblies

This part of IEC 61189 is used for evaluating the changes to the surface insulation resistance
of a pre-selected material set on a representative test coupon and quantifies the deleterious
effects of improperly used materials and processes that can lead to decreases in electrical
resistance.
An assembly process involves a number of different process materials including solder flux,
solder paste, solder wire, underfill materials, adhesives, staking compounds, temporary
masking materials, cleaning solvents, conformal coatings and more. The test employs two
different test conditions of 85 °C and 85 % relative humidity (RH), preferred for a process that
includes cleaning, or 40 °C and 90 % relative humidity (RH), preferred for processes where no
cleaning is involved.
NOTE 40 °C and 93 % RH can be used as an alternative to 40 °C and 90 % RH. Additional information is provided
in 5.4 and A.5.2.
Testing is material (set) and process / equipment specific. Qualifications are to be performed
using the production intent equipment, processes and materials.

Prüfverfahren für Elektromaterialien, Leiterplatten und andere Verbindungsstrukturen und Baugruppen - Teil 5-502: Allgemeine Prüfverfahren für Materialien und Baugruppen - Prüfung des Oberflächenisolationswiderstands (OIW) von Baugruppen

Méthodes d’essai pour les matériaux électriques, les cartes imprimées et autres structures d’interconnexion et ensembles - Partie 5-502: Méthodes d'essai générales pour les matériaux et les ensembles - Essais de résistance d'isolement en surface (RIS) des ensembles

L’IEC 61189-5-502:2021 permet d’évaluer les variations de la résistance d’isolement en surface d’un ensemble de matériaux présélectionné sur une éprouvette représentative et quantifie les effets délétères d’une mauvaise utilisation des matériaux et des processus qui peuvent provoquer une diminution de la résistance électrique.

Preskusne metode za električne materiale, tiskana vezja ter druge povezovalne strukture in sestave - 5-502. del: Splošne preskusne metode za materiale in sestave - Preskušanje površinske izolacijske upornosti sestavov

General Information

• Status: Published
• Publication Date: 28-Apr-2021
• ICS: 31.180 - Printed circuits and boards
• ICS: 31.190 - Electronic component assemblies
• Technical Committee: ITIV - Electronics assembly technology and Environmental standardization
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 18-Mar-2021
• Due Date: 23-May-2021
• Completion Date: 29-Apr-2021
• Ref Project: EN IEC 61189-5-502:2021 - Test methods for electrical materials, printed board and other interconnection structures and assemblies - Part 5-502: General test methods for materials and assemblies - Surface insulation resistance (SIR) testing of assemblies

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN IEC 61189-5-502:2021
01-junij-2021
Preskusne metode za električne materiale, tiskana vezja ter druge povezovalne
strukture in sestave - 5-502. del: Splošne preskusne metode za materiale in
sestave - Preskušanje površinske izolacijske upornosti sestavov
Test methods for electrical materials, printed boards and other interconnection structures
and assemblies - Part 5-502: General test methods for materials and assemblies -
Surface insulation resistance (SIR) testing of assemblies
Ta slovenski standard je istoveten z: EN IEC 61189-5-502:2021
ICS:
31.180 Tiskana vezja (TIV) in tiskane Printed circuits and boards
plošče
31.190 Sestavljeni elektronski Electronic component
elementi assemblies
SIST EN IEC 61189-5-502:2021 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 61189-5-502:2021


EUROPEAN STANDARD EN IEC 61189-5-502

NORME EUROPÉENNE

EUROPÄISCHE NORM
March 2021
ICS 31.180

English Version
Test methods for electrical materials, printed board and other
interconnection structures and assemblies - Part 5-502: General
test methods for materials and assemblies - Surface insulation
resistance (SIR) testing of assemblies
(IEC 61189-5-502:2021)
Méthodes d'essai pour les matériaux électriques, les cartes Prüfverfahren für Elektromaterialien, Leiterplatten und
imprimées et autres structures d'interconnexion et andere Verbindungsstrukturen und Baugruppen - Teil 5-
ensembles - Partie 5-502: Méthodes d'essai générales pour 502: Allgemeine Prüfverfahren für Materialien und
les matériaux et les ensembles - Essais de résistance Baugruppen - Prüfung des
d'isolement en surface (RIS) des ensembles Oberflächenisolationswiderstands (SIR) von Baugruppen
(IEC 61189-5-502:2021) (IEC 61189-5-502:2021)
This European Standard was approved by CENELEC on 2021-03-10. 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
© 2021 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN IEC 61189-5-502:2021 E

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SIST EN IEC 61189-5-502:2021
EN IEC 61189-5-502:2021 (E)
European foreword
The text of document 91/1646/CDV, future edition 1 of IEC 61189-5-502, prepared by IEC/TC 91
"Electronics assembly technology" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN IEC 61189-5-502:2021.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2021-12-10
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2024-03-10
document have to be withdrawn
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.
Endorsement notice
The text of the International Standard IEC 61189-5-502:2021 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 61189-1 NOTE Harmonized as EN 61189-1
IEC 61189-3 NOTE Harmonized as EN 61189-3
IEC 61189-5 (series) NOTE Harmonized as EN IEC 61189-5 (series)
IEC 61189-6 NOTE Harmonized as EN 61189-6
IEC 61190-1-1 NOTE Harmonized as EN 61190-1-1
IEC 61190-1-2 NOTE Harmonized as EN 61190-1-2
IEC 61249-2-7 NOTE Harmonized as EN 61249-2-7
IEC 62137-4:2014 NOTE Harmonized as EN 62137-4:2014 (not modified)
ISO 9001 NOTE Harmonized as EN ISO 9001
ISO 9455-1 NOTE Harmonized as EN 29455-1
ISO 9455-2 NOTE Harmonized as EN ISO 9455-2
2

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SIST EN IEC 61189-5-502:2021
EN IEC 61189-5-502:2021 (E)
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 60068-1 - Environmental testing - Part 1: General EN 60068-1 -
and guidance
IEC 60068-2-20 - Environmental testing - Part 2-20: Tests - EN 60068-2-20 -
Test T: Test methods for solderability
and resistance to soldering heat of
devices with leads
IEC 60068-2-58 - Environmental testing - Part 2-58: Tests - EN 60068-2-58 -
Test Td: Test methods for solderability,
resistance to dissolution of metallization
and to soldering heat of surface
mounting devices (SMD)
IEC 60068-2-67 - Environmental testing - Part 2-67: Tests - EN 60068-2-67 -
Test Cy: Damp heat, steady state,
accelerated test primarily intended for
components
IEC 60068-2-78 - Environmental testing - Part 2-78: Tests - EN 60068-2-78 -
Test Cab: Damp heat, steady state
IEC 60194 - Printed board design, manufacture and - -
assembly - Terms and definitions
IEC 61190-1-3 - Attachment materials for electronic EN IEC 61190-1-3 -
assembly - Part 1-3: Requirements for
electronic grade solder alloys and fluxed
and non-fluxed solid solder for electronic
soldering applications

3

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SIST EN IEC 61189-5-502:2021




IEC 61189-5-502

®


Edition 1.0 2021-02




INTERNATIONAL



STANDARD




NORME


INTERNATIONALE
colour

inside










Test methods for electrical materials, printed board and other interconnection

structures and assemblies –

Part 5-502: General test methods for materials and assemblies – Surface

Insulation Resistance (SIR) testing of assemblies



Méthodes d’essai pour les matériaux électriques, les cartes imprimées et autres


structures d’interconnexion et ensembles –

Partie 5-502: Méthodes d’essai générales pour les matériaux et les ensembles –

Essais de résistance d’isolement en surface (RIS) des ensembles











INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 31.180 ISBN 978-2-8322-9290-7




Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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SIST EN IEC 61189-5-502:2021
– 2 – IEC 61189-5-502:2021 © IEC 2021
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Equipment/Apparatus . 7
4.1 Soldering and other production process equipment . 7
4.2 Measurement instrument . 7
4.3 Resistor verification coupon . 8
4.4 Damp heat chamber . 8
4.5 Magnifiers (10x – 30x) . 9
4.6 Camera . 9
4.7 Cleaning solvent . 9
4.8 Interconnecting cable . 9
4.9 Connector rack . 9
4.10 Solder flux . 9
5 Test coupon. 9
5.1 Test coupon artwork . 9
5.1.1 General . 9
5.1.2 Test coupon . 10
5.1.3 Laminate . 10
5.1.4 Surface finish . 10
5.1.5 Solder mask . 10
5.1.6 Quality . 10
5.2 Components (bill of materials) . 10
5.3 Number of test coupons . 12
5.4 Test conditions . 12
5.5 Coupon identification . 13
6 Procedure . 13
6.1 Test coupon preparation . 13
6.2 Cleaning . 13
6.3 Manufacturing process replication . 13
6.4 Preparation of samples for chamber . 13
6.5 Connector system – High-resistance measurement verification . 13
6.6 Hard wiring . 14
6.7 Coupon orientation in the chamber . 14
6.8 Test coupon measurements . 14
6.9 Evaluation . 15
6.10 Test report . 15
6.11 Additional information . 16
Annex A (informative) Additional information . 17
A.1 Additional information . 17
A.1.1 General . 17
A.1.2 Advisory notes . 17
A.1.3 Use of coupon test pattern on production product . 17
A.2 Use of dummy components . 17
A.3 Frequency of monitoring . 17

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IEC 61189-5-502:2021 © IEC 2021 – 3 –
A.4 Condensation . 18
A.5 Flux volatilisation . 18
A.5.1 General . 18
A.5.2 90 % RH or 93 % RH . 18
A.6 Drip shield . 18
A.7 Inspection . 19
A.8 Connector test racks . 19
A.8.1 Advantages . 19
A.8.2 Disadvantages . 19
A.9 Electromagnetic shielding . 19
A.10 Wiring to the IPC B-52 test coupons . 20
A.11 Connector test rack wiring. 21
A.12 Test voltage . 21
Bibliography . 22

Figure 1 – Resistor verification coupon using the IPC-B-52 coupon . 8
Figure 2 – IPC B-52 Rev B Top Side . 11
Figure 3 – IPC B-52 Rev B bottom side . 11
Figure 4 – Test specimen location with respect to chamber air flow . 14

Table 1 – IPC B-52 bill of materials (BOM) . 12
Table A.1 – IPC B-52 Rev B wiring diagram . 20

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

TEST METHODS FOR ELECTRICAL MATERIALS, PRINTED BOARD AND
OTHER INTERCONNECTION STRUCTURES AND ASSEMBLIES –

Part 5-502: General test methods for materials and assemblies –
Surface Insulation Resistance (SIR) testing of assemblies


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,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
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
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
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
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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 Publications.
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.
IEC 61189-5-502 has been prepared by IEC technical committee 91: Electronics assembly
technology. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
91/1646/CDV 91/1673/RVC

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.

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SIST EN IEC 61189-5-502:2021
IEC 61189-5-502:2021 © IEC 2021 – 5 –
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 in the IEC 61189 series, published under the general title Test methods for
electrical materials, printed board and other interconnection structures and assemblies, 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 "http://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.

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TEST METHODS FOR ELECTRICAL MATERIALS, PRINTED BOARD AND
OTHER INTERCONNECTION STRUCTURES AND ASSEMBLIES –

Part 5-502: General test methods for materials and assemblies –
Surface Insulation Resistance (SIR) testing of assemblies



1 Scope
This part of IEC 61189 is used for evaluating the changes to the surface insulation resistance
of a pre-selected material set on a representative test coupon and quantifies the deleterious
effects of improperly used materials and processes that can lead to decreases in electrical
resistance.
An assembly process involves a number of different process materials including solder flux,
solder paste, solder wire, underfill materials, adhesives, staking compounds, temporary
masking materials, cleaning solvents, conformal coatings and more. The test employs two
different test conditions of 85 °C and 85 % relative humidity (RH), preferred for a process that
includes cleaning, or 40 °C and 90 % relative humidity (RH), preferred for processes where no
cleaning is involved.
NOTE 40 °C and 93 % RH can be used as an alternative to 40 °C and 90 % RH. Additional information is provided
in 5.4 and A.5.2.
Testing is material (set) and process / equipment specific. Qualifications are to be performed
using the production intent equipment, processes and materials.
2 Normative references
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.
IEC 60068-1, Environmental testing – Part 1: General and guidance
IEC 60068-2-20, Environmental testing – Part 2-20: Tests – Test T: Test methods for
solderability and resistance to soldering heat of devices with leads
IEC 60068-2-58, Environmental testing – Part 2-58: Tests – Test Td: Test methods for
solderability, resistance to dissolution of metallization and to soldering heat of surface mounting
devices (SMD)
IEC 60068-2-67, Environmental testing – Part 2-67: Tests – Test Cy: Damp heat, steady state,
accelerated test primarily intended for components
IEC 60068-2-78, Environmental testing – Part 2-78: Tests – Test Cab: Damp heat, steady state
IEC 60194, Printed board design, manufacture and assembly – Terms and definitions
IEC 61190-1-3, Attachment materials for electronic assembly – Part 1-3: Requirements for
electronic grade solder alloys and fluxed and non-fluxed solid solder for electronic soldering
applications

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SIST EN IEC 61189-5-502:2021
IEC 61189-5-502:2021 © IEC 2021 – 7 –
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60068-1, IEC 60068-
2-20:2008, IEC 60068-2-58, IEC 60194, and IEC 61190-1-3 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
test coupon
test specimen, test vehicle, test sample
4 Equipment/Apparatus
4.1 Soldering and other production process equipment
All the equipment shall represent the equipment to be used in production.
4.2 Measurement instrument
This shall consist of a measuring device capable of measuring insulation resistance in the range
6 12
of at least 10 Ω to 10 Ω.
It shall be capable of measuring and recording each individual test pattern of an IPC-B-52 test
board/assembly. The measurement circuit shall incorporate a 1 MΩ current limiting resistor in
each current pathway.
The tolerance of the total measurement system shall be:
10
• ±5 % up to 10 Ω at 5 V;
10 11
• ±10 % between 10 Ω to 10 Ω at 5 V;
11
• ±20 % above 10 Ω at 5 V.
If a different test voltage is to be used, the measurement circuit shall be assessed at that voltage
rather than the 5 V stipulated. See 6.8 and Clause A.12 for additional information on test
voltages.
The resistors used to confirm the "total measurement system tolerance" defined above, shall
have a purchased tolerance of:
6
• ±0,1 % up to and including 10 Ω;
6 8
• ±1 % above 10 Ω and up to and including 10 Ω;
8 10
• ±5 % above 10 Ω and up to and including 10 Ω;
10
• ±10 % above 10 Ω.
The instrument can be used with either an external or internal power supply but shall be capable
of delivering a variable voltage from (5 to 100) V DC ±1 % with a 1 MΩ load and a channel to
13
channel isolation resistance of 10 Ω.
The system shall be capable of taking measurements in the time interval required.

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Equipment shall have the measurement capability to repeat the resistance measurement on all
channels at least every 20 min.
4.3 Resistor verification coupon
The measurement system measurement performance shall be verified by substituting a resistor
verification coupon (see Figure 1) in place of the test coupons while in the chamber at both
ambient and elevated conditions.
This coupon should be fitted with at least 4 “known value” resistors. The tolerances for the
“known value” resistors shall be as per the purchased tolerances detailed in 4.2.

Figure 1 – Resistor verification coupon using the IPC-B-52 coupon
The resistor verification coupon should have a protective metal (stainless steel) cover attached
with stainless hardware to the grounded mounting holes on the coupon to protect the resistors
from contamination or damage during handling operations.
Other types of test coupon may be used in place of the IPC-B-52 RVC, as this coupon is used
only to verify continuity prior to the commencement of the test.
4.4 Damp heat chamber
° ° °
A damp heat chamber capable of being adjusted to a temperature of 20 C ± 2 C to 100 C
± 2 °C and of relative humidity between 80 % RH ±3 % RH and 90 % RH ± 3 % RH according
to IEC 60068-2-67 and IEC 60068-2-78 shall be used.
If the alternative conditions of 40 °C and 93 % RH are to be used, the damp heat chamber shall
be capable of the upper humidity level of 93 % RH ± 3 % RH rather than the 90 % RH ± 3 %
RH specified above; see 5.4 and A.5.1 for further information.
The chamber shall be constructed with stainless steel inner surfaces and be well-insulated.
The temperature and humidity measurement should be taken using sensors such as dry and
wet bulb thermometers or solid-state sensors. The temperature and humidity levels of the test
chamber shall be recorded at a minimum of 5 minute intervals throughout the test, preferably with
independent control sensors.
The location of the samples within the chamber should ensure that the airflow within is not
impeded.

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IEC 61189-5-502:2021 © IEC 2021 – 9 –
Adequate mixing of water vapour and air is imperative to ensure condensation does not occur
anywhere in the chamber except on/around cooling or dehumidification coils. If any part of
interior of the chamber is below the dew point, possibly due to insulation or control issues,
condensation will occur. The samples should be kept above the dew point and be shielded from
dripping or flying condensate.
Prior to every test, the chamber interior shall be wiped down with a mixture of 50 % propan-2-
ol and 50 % deionized water. The chamber sh
...