TC 112 - Evaluation and qualification of electrical insulating materials and systems

IEC TS 61934:2024 is available as IEC TS 61934:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC TS 61934:2024 is applicable to the off-line electrical measurement of partial discharges (PDs) that occur in electrical insulation systems (EISs) when stressed by repetitive voltage impulses generated from power electronics devices.
Typical applications are EISs belonging to apparatus driven by power electronics, such as motors, inductive reactors, wind turbine generators and the power electronics modules themselves.
NOTE Use of this document with specific products can require the application of additional procedures.
Excluded from the scope of this document are:
- methods based on optical or ultrasonic PD detection,
- fields of application for PD measurements when stressed by non-repetitive impulse voltages such as lightning impulse or switching impulses from switchgear.
This edition includes the following significant technical changes with respect to the previous edition:
a) background information on the progress being made in the field of power electronics including the introduction of wide band gap semiconductor devices has been added to the Introduction;
b) voltage impulse generators; the parameter values of the voltage impulse waveform have been modified to reflect application of wide band gap semiconductor devices.
c) PD detection methods; charge-based measurements are not described in this third edition nor are source-controlled gating techniques to suppress external noise.
d) Since the previous edition in 2011, there have been significant technical advances in this field as evidenced by several hundreds of publications. Consequently, the Bibliography in the 2011 edition has been deleted in this third edition.

IEC 62631-3-2:2023 describes methods of test for the determination of surface resistance and surface resistivity of electrical insulation materials by applying DC voltage. This edition includes the following significant technical changes with respect to the previous edition:
a) descriptions of the electrode arrangements have been clarified;
b) new descriptions of the conductive means have been added;
c) a new informative Annex B summarizing the results of the comparative verification study on surface resistivities using different electrode arrangements has been added.

IEC 62631-3-1:2023 is available as IEC 62631-3-1:2023 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 62631-3-1:2023 specifies a method of test for the determination of volume resistance and volume resistivity of electrical insulating materials by applying a DC voltage. This edition includes the following significant technical changes with respect to the previous edition:
- following the withdrawal of IEC 60093 and its partial replacement with the first edition of IEC 62631-3-1, the missing editorial and technical texts have been added and incorporated into this second edition of IEC 62631-3-1;
- the alignment of normative texts and informative notes have been addressed as well as the normative references and bibliography.

IEC 60216-6:2022 specifies the experimental and calculation procedures for deriving the thermal endurance characteristics, temperature index (TI) and relative temperature index (RTI) of an electrical insulating material (EIM) using the “fixed time frame method (FTFM)”. In this protocol, the ageing takes place for a small number of fixed times, using the appro­priate number of ageing temperatures throughout each time, the properties of the specimens being measured at the end of the relevant time interval. This differs from the procedure of IEC 60216-1, where ageing is conducted at a small number of fixed temperatures, property measurement taking place after ageing times dependent on the progress of ageing. The diagnostic tests employed in the fixed time frame method are restricted to destructive tests. The method has not yet been applied to non-destructive or proof test procedures. This edition includes the following significant technical changes with respect to the previous edition:
- clarification of definition of index properties vs. endurance properties;
- complete rework of Annex G and the corresponding program.

IEC 60216-5:2022 specifies the experimental and calculation procedures to be used for deriving the relative temperature index of a material from experimental data obtained in accordance with the instructions of IEC 60216-1 and IEC 60216-2. The calculation procedures are supplementary to those of IEC 60216-3. Guidance is also given for assessment of thermal ageing after a single fixed time and temperature, without extrapolation. This edition includes the following significant technical changes with respect to the previous edition:
Annex C “Computer program” has been completely reworked;
in 3.1, the terms “ATE” and “RTE” were replaced by “ATI” and “RTI” to emphasize their reference to an electrical insulating material (EIM).
This standard is to be read in conjunction with IEC 60216-1:2013, IEC 60216-2:2005 and IEC 60216-3:2021.

IEC 60544-5:2022 is available as IEC 60544-5:2022 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 60544-5:2022 covers ageing assessment methods which can be applied to components based on polymeric materials (e.g. cable insulation and jackets, elastomeric seals, polymeric coatings, gaiters) which are used in environments where they are exposed to radiation. The object of this document is aimed at providing methods for the assessment of ageing in service. The approaches discussed in Clause 5 through Clause 9 cover ageing assessment programmes based on condition monitoring (CM), the use of sample deposits in severe environments and sampling of real-time aged components. This edition includes the following significant technical changes with respect to the previous edition:
- added recent references in 7.4 showing that some electrical condition monitoring methods show promising correlations with ageing;
- updated recommendations for implementation of a sample deposit in 9.2, installation of a sample deposit in 9.3 and testing of samples from the deposit in 9.4;
- updated list of references.

IEC 62631-2-2:2022 specifies test methods for the determination of permittivity and dissipation factor properties of solid insulating materials in a high frequency range from 1 MHz to 300 MHz.

IEC 60587:2022 describes two test methods for the evaluation of electrical insulating materials for use under severe ambient conditions at power frequencies (45 Hz to 65 Hz) by the evaluation of the resistance to tracking and erosion, using a liquid contaminant and inclined plane specimens. The two methods are:
- Method 1: test at constant voltage,
- Method 2: test at stepwise increased voltage.
Method 1 is the most widely used method as there is less need for continual inspection.
The test conditions are designed to accelerate the production of the effects, but do not reproduce all the conditions encountered in service.
This edition includes the following significant technical changes with respect to the previous edition:
a) an improved description of the experimental methods has been implemented;
b) an improved description of the preparation of the test specimens has been implemented;
c) a more detailed description of the electrode material and of the electrode quality has been added;
d) evaluation criterion B (track length) has been removed for testing according to test method 2 (stepwise tracking voltage) as it is not applicable.

IEC TR 62039:2021(E) presents the important material properties of polymeric materials used in outdoor insulation and, where applicable, lists standardized test methods including minimum requirements. If no standardized tests are available, the test methods reported in literature are summarized.
This document is valid for insulating materials having polymeric insulation, which are used in outdoor high voltage electrical applications with a system voltage greater than 1 000 V AC and 1 500 V DC (several tests are only defined for alternating current, which are not applicable for direct current). Such applications are relevant where the housing is an integral part of the device, for example in surge arresters and cable terminations. The scope of this document is limited to the insulation materials only and is not generally intended for coating materials (coating materials are, for example, thin layers applied on toughened glass and ceramic). Some tests mentioned in this document are applicable for coating and are under consideration by CIGRE. The performance of insulators in service depends on several factors such as the type of material, the design and environmental conditions. Consequently, the choice of materials that fulfil the requirements listed in Table 1 is a necessary condition but does not guarantee satisfactory performance when used in outdoor insulation.

IEC 60216-3:2021 is available as IEC 60216-3:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60216-3:2021 specifies the calculation procedures used for deriving thermal endurance characteristics from experimental data obtained in accordance with the instructions of IEC 60216-1 and IEC 60216-2, using fixed ageing temperatures and variable ageing times. The experimental data can be obtained using non-destructive, destructive or proof tests. Data obtained from non-destructive or proof tests can be incomplete, in that it is possible that measurement of times taken to reach the end-point will have been terminated at some point after the median time but before all specimens have reached end-point. The procedures are illustrated by worked examples, and suitable computer programs are recommended to facilitate the calculations.
This edition includes the following significant technical changes with respect to the previous edition:
- a new computer program has been included;
- Annex E " has been completely reworked.

IEC TR 61858-3:2020(E) provides information on the identification of electrical insulating materials and auxiliary components for the assessment of modifications to an established insulation system and gives guidance on the selection of feasible test procedures.

IEC TS 62836:2020(E) provides an efficient and reliable procedure to test the internal electric field in the insulating materials used for high-voltage applications, using the pressure wave propagation (PWP) method. It is suitable for a sample with homogeneous insulating materials and an electric field higher than 1 kV/mm, but it is also dependent on the thickness of the sample and the pressure wave generator.

IEC 60112:2020 specifies the method of test for the determination of the proof and comparative tracking indices of solid insulating materials on pieces taken from parts of equipment and on plaques of material using alternating voltage. This document provides a procedure for the determination of erosion when required.
This test method evaluates the composition of the material as well as the surface of the material being evaluated. Both the composition and surface condition directly influence the results of the evaluation and are considered when using the results in material selection process.
Test results are not directly suitable for the evaluation of safe creepage distances when designing electrical apparatus.
This basic safety publication focusing on a safety test method is primarily intended for use by technical committees in the preparation of safety publications in accordance with the principles laid down in IEC Guide 104 and lSO/lEC Guide 51.
This edition includes the following significant technical changes with respect to the previous edition:
Introduction of a new contaminant, solution C with a surfactant aligned with the test method of IEC 60587. The definition of the solution B was transferred to Annex B for backward reference.
Introduction of a screening test, considering the fact that some materials can withstand high test voltages, but fail at lower test voltages.
It has the status of a basic safety publication in accordance with IEC Guide 104.

IEC 61857-32:2019 series is focused on applications where other possible factors need to be incorporated to evaluate any influence on the performance of the electrical insulation system (EIS). Multi-factor evaluation is the most complex type of project to design and conduct. Clear guidelines are needed to give the user of this document a uniform approach and a method to analyse the test results.
This document is for applications where the stresses are some combination of other factors of influence identified in IEC 60505. The multi-factor stresses are applied during the diagnostic portion of each test cycle.
A few examples of other factors of influence or multi-factor stresses are:
– high vibration;
– submersion in oils, water, or solutions;
– voltage higher than the test voltage of the reference EIS;
– decreased cold shock temperature.

IEC TR 61244-4:2019(E) provides general guidance for the evaluation/verification of electrical insulation materials (EIM) and electrical insulation systems (EIS) intended to be used in types of equipment exposed to ionizing radiation. Beside sensors, actuators/motors as well as plugs and terminals, cables are a well-known typical application of those EIM and EIS. Their type spectrum covers low voltage power cables, control cables and instrumentation cables. Because of their comparable simple design, cables are the ideal type of equipment to study EIM and EIS degradation processes. But the results of these studies can be easily transferred to the enumerated types of equipment.
Nonetheless, this document provides a state-of-the art report on qualification/verification procedures used to simulate simultaneous effects of temperature and radiation at varying intensities rather than give detailed test programmes valid for specific test methods.
NOTE 1 Use of this document with specific products can require specification of additional product related procedures.
NOTE 2 Some of the procedures described in this document are emerging technologies. Therefore, specified prerequisites, former experiences as well as boundary conditions can be additionally taken into account.

IEC 62631-3-4:2019 covers procedures for the determination of insulation resistance and volume resistivity of insulating materials by applying DC-voltage and temperatures up to 800 °C. The typical application materials include high temperature mica plate and alumina ceramics.
This edition of IEC 62631-3-4 cancels and replaces IEC 60345 “Method of test for electrical resistance and resistivity of insulating materials at elevated temperatures”, published in 1971. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to IEC 60345:  
The revised standard becomes part of the series IEC 62631-3-x. Title of the standard is changed and adapted to the series as Part 3-4.
Clauses 2 "Normative references", 3 "Terms and definitions", and 4 "Significance" are added.
Subclauses 5.2 "Power supply, Voltage", 5.3.1.2 "Number of test specimens" and 5.3.1.3 "Conditioning and pre-treatment of test specimens" are added.
In 5.3.5 "Special precautions during measurements", errors analysis in the measurement of current are modified, and aligned with IEC 62631-3-1.
In 6.2 "Increasing the temperature by steps (method B)", the method for more than one specimen is removed.
The standard atmospheric conditions for testing and conditioning, especially the temperature, are replaced according to IEC 60212.
The circuit diagram of test apparatus is modified, and the structure diagram and pictures of test apparatus are added in Annex A.
The orders of part clauses are adjusted.

IEC 62631-2-1:2018 describes test methods for the determination of permittivity and dissipation factor properties of solid insulating materials (AC methods from 0,1 Hz up to 10 MHz).
This first edition cancels and replaces the first edition IEC 60250, published in 1969. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a. technical frequencies confined to AC methods;
b. update on measurements on solid dielectric materials.

IEC 62631-3-11:2018 covers a method of test for the determination of volume resistance and volume resistivity of electrical insulation materials by applying DC voltage. It covers the materials described in IEC 60455-3-5, IEC 60464-3-1, IEC 60464-3-2 and similar products.

IEC TR 60493-3:2017(E) clarifies how a statistical analysis can be done with a small number of samples.
This document will be useful when the accelerated test method is difficult to carry out, for example in cases where the dimensions of test specimens (including test devices) are very large in scale or the cost of test specimens is high. Testing is facilitated by enabling users to reduce the number of test specimens.

IEC 61857-31:2017 establishes an EIS evaluation for applications with a designed life of 5 000 h or less. This test method follows the procedures of IEC 60505 and is modified based on the range of designed life.

IEC TR 60216-7-2:2016(E), which is a Technical Report, is to validate the procedures of IEC TS 60216-7-1 in providing a similar temperature index to conventional methods used in other parts of the IEC 60216 series. These round robin test results do not provide statistical analysis for precisions. The round robin test focuses on preliminary studies to understand the evaluation and calculation procedures, influence on apparatus, and data variance among laboratories before determination of precisions.

IEC TS 62332-3:2016 is applicable to EIM and EIS containing solid and liquid components where the refrigerant, oil and thermal stresses are the dominant ageing factor, without restriction to voltage class.

IEC 62631-3-1:2016 covers a method of test for the determination of volume resistance and volume resistivity of electrical insulation materials by applying a DC voltage. This edition includes the following significant technical changes with respect to the second edition of IEC 60093:
a) IEC 60093 has been completely revised, both editorially and technically, and incorporated into the new IEC 62631 series;
b) test methods have been updated to current day state of the art;
c) volume and surface resistance and resistivity are now separated to appear in this part of IEC 62631 and in IEC 62631-3-2, respectively.

IEC 62631-3-3:2015 covers methods of test for the determination of the insulation resistance of electrical insulating materials or insulating systems by applying DC voltage. This first edition cancels and replaces the first edition of IEC 60167, published in 1964, and constitutes a technical revision. This edition includes the following significant technical changes with respect to the first edition of IEC 60167:
a) IEC 60167 has been completely revised, both editorially and technically, and incorporated into the new IEC 62631 series;
b) test methods have been updated to current day state of the art.

IEC 62631-3-2:2015 covers methods of test for the determination of surface resistance and surface resistivity of electrical insulation materials by applying DC voltage. This first edition cancels and replaces the second edition of IEC 60093, published in 1980, and constitutes a technical revision. This edition includes the following significant technical changes with respect to the second edition of IEC 60093:
a) IEC 60093 has been completely revised, both editorially and technically, and incorporated into the new IEC 62631 series;
b) test methods have been updated to current day state of the art;
c) volume and surface resistance and resistivity are now separated into IEC 62631-3-1 and IEC 62631-3-2, respectively.

IEC 61251:2015 describes many of the factors involved in voltage endurance tests on electrical insulating materials and systems. It describes the voltage endurance graph, lists test methods illustrating their limitations and gives guidance for evaluating the sinusoidal a.c. voltage endurance of insulating materials and systems from the results of the tests. This International Standard is applicable over the voltage frequency range 20 Hz to 1 000 Hz. The general principles can also be applicable to other voltage shapes, including impulse voltages. The terminology to be used in voltage endurance is defined and explained. This first edition of IEC 61251 cancels and replaces the second edition of IEC TS 61251, published in 2008. This edition constitutes a technical revision and includes the following significant technical changes with respect to the second edition of IEC TS 61251:
a) upgrade from Technical Specification to an International Standard;
b) clarification of issues raised since publication of IEC TS 61251.

IEC TR 61857-2:2015(E) gives guidelines to identify the appropriate test method to be used for the evaluation of a proposed Electrical Insulation System (EIS). Some of the standards are for evaluation and classification of the EIS, while other standards identify the appropriate method to evaluate single or multi-factor stresses of a proposed or of an established EIS. This Technical Report is applicable to existing or proposed EIS used in electrotechnical products across a wide range of operating voltages of IEC Standards. The report takes care to select the appropriate standard based on construction and intended operating conditions.

IEC TS 60216-7-1:2015(E) describes the procedure for the evaluation of the thermal endurance of electrical insulating materials, based on thermal analysis methods for the evaluation of the activation energy of the thermal degradation reaction and a conventional life test providing a life point in the thermal endurance graph. The purpose of the test procedure is to estimate the relative temperature index (RTE).

IEC TS 61244-2:2014, which is a technical specification, applies to procedures for predicting ageing of polymeric materials at low dose rates. The object is to present three methods which can be used to extrapolate data obtained from high dose rate experiments to the low dose rates typical of service conditions. The techniques described are methods which have been found to be useful for a range of elastomeric, thermoplastic and thermoset materials. This edition includes the following significant technical changes with respect to the previous edition:
a) examples and background information moved to annexes;
b) examples updated with more recent references.

IEC TS 61244-1:2014, which is a technical specification, reviews experimental techniques to quantitatively monitor the effects when oxygen is present during ageing of polymers in various environments including temperature, radiation or ultraviolet. This edition includes the following significant technical changes with respect to the previous edition:
a) numerical simulation of DLO is much improved;
b) geometry of samples has been expanded from only the case of the infinite plane to the cylindrical and the spherical cases.

IEC TS 62332-2:2014 is applicable to EIS containing solid and liquid components where the thermal stress is the dominant ageing factor, without restriction to voltage class. This part specifies a sealed tube test procedure for the thermal evaluation and qualification of electrical insulation systems (EIS). One aspect of this procedure is to also provide a method to assign thermal classifications to materials used in EIS where solid and liquid components are both used. This procedure describes a comparative ageing method whereby a reference system composed of kraft paper and mineral oil is compared to a candidate system of any combination of solid and insulating liquid. The test procedures in this part are specifically applicable to liquid immersed transformer insulation systems.

IEC 61858-1:2014 lists the required test procedures for qualification of modifications of an established electrical insulation system (EIS) with respect to its thermal classification. This standard is applicable to EIS used in wire-wound winding electrotechnical devices. The test procedures are comparative in that the performance of a candidate EIS is compared to that of a reference EIS, which has proven service experience in accordance with IEC 60505 or has been evaluated by one of the procedures given in the IEC 61857 series. This first edition of IEC 61858-1 cancels and replaces the third edition of IEC 61858, published in 2008. It constitutes a technical and editorial revision. This edition includes the following significant technical changes with respect to the previous edition:
a) this part is specifically for wire-wound winding EIS;
b) new figures and charts support the contents.

IEC 61858-2:2014 lists the required test procedures for qualification of modifications of an established electrical insulation system (EIS) with respect to its thermal classification. This standard is applicable to EIS used in form-wound electrotechnical devices. The test procedures are comparative in that the performance of a candidate EIS is compared to that of a reference EIS, which has proven service experience in accordance with IEC 60505 or has been evaluated by one of the procedures given in IEC 60085 and IEC 60034-18-31.

L'IEC 60243-2:2013 donne les exigences complémentaires à celles de la CEI 60243-1 pour la détermination de la rigidité diélectrique des matériaux isolants solides sous tension continue. Cette troisième édition annule et remplace la deuxième édition parue en 2001 et constitue une révision éditoriale.
Cette publication doit être lue conjointement avec la CEI 60243-1:2013.

IEC 60243-3:2013 gives requirements additional to those in IEC 60243-1 for the determination of the electric strength of solid insulating materials under 1,2/50 µs impulse voltage stress. This third edition cancels and replaces the second edition, published in 2001, and constitutes an editorial revision.
This publication is to be read in conjunction with IEC 60243-1:2013.

IEC 60544-1:2013 deals broadly with the aspects to be considered in evaluating the effects of ionizing radiation on all types of organic insulating materials. It also provides, for X-rays, gamma-rays, and electrons, a guide to dosimetry terminology, methods for dose measurements, testing carried out at irradiation facilities, evaluation and testing of material characteristics and properties, documenting the irradiation process. This edition includes the following significant technical changes with respect to the previous edition:
a) recent advances in simulation methods of radiation interaction with different matter enables the prediction of the energy-deposition profile in matter and design the irradiation procedure;
b) many new dosimetry systems have become available.

IEC 60243-1:2013 provides test methods for the determination of short-time electric strength of solid insulating materials at power frequencies between 48 Hz and 62 Hz. This standard does not cover the testing of liquids and gases, although these are specified and used as impregnates or surrounding media for the solid insulating materials being tested. NOTE: Methods for the determination of breakdown voltages along the surfaces of solid insulating materials are included.

IEC 60216-8:2013 specifies the general ageing conditions and simplified procedures to be used for deriving thermal endurance characteristics, which are shown by temperature index (TI) and/or relative temperature index (RTI) and the halving interval (HIC). The procedures specify the principles for evaluating the thermal endurance properties of materials exposed to elevated temperature for long periods. In the application of this standard, it is assumed that a practically linear relationship exists between the logarithm of the time required to cause the predetermined property change and the reciprocal of the corresponding absolute temperature (Arrhenius relationship). For the valid application of the standard, no transition, in particular no first-order transition should occur in the temperature range under study.

IEC 60216-1:2013 specifies the general ageing conditions and procedures to be used for deriving thermal endurance characteristics and gives guidance in using the detailed instructions and guidelines in the other parts of the standard. Although originally developed for use with electrical insulating materials and simple combinations of such materials, the procedures are considered to be of more general applicability and are widely used in the assessment of materials not intended for use as electrical insulation. In the application of this standard, it is assumed that a practically linear relationship exists between the logarithm of the time required to cause the predetermined property change and the reciprocal of the corresponding absolute temperature (Arrhenius relationship). For the valid application of the standard, no transition, in particular no first-order transition should occur in the temperature range under study. This sixth edition cancels and replaces the fifth edition, published in 2001. It constitutes an editorial revision where the simplified method has been removed and now forms Part 8 of the IEC 60216 series: Instructions for calculating thermal endurance characteristics using simplified procedures.

IEC 62068:2013 applies to electrical equipment, regardless of voltage, containing an insulation system, which is:
- connected to an electronic power supply, and
- requires an evaluation of insulation endurance under repetitive voltage impulses. This standard proposes a general test procedure to facilitate screening of electrical insulating materials (EIM) and systems (EIS) and to achieve a relative evaluation of insulation endurance under conditions of repetitive impulses. This first edition of IEC 62068 replaces IEC 62068-1:2003. It has been re-numbered as IEC 62068, as decided at the Plenary Meeting of TC 112 in Prague 2011. The main changes with regard to IEC 62068-1:2003 concern the terms and definitions which are now aligned, in part, on IEC/TS 61934 and IEC/TS 60034-18-42.

IEC/TS 62758:2012(E) presents a standard method to estimate the performance of a pulsed electro-acoustic (PEA) measurement system. For this purpose, a systematic procedure is recommended for the calibration of the measurement system. Using the procedure, users can estimate whether the system works properly or not.

IEC 60544-2:2012 specifies the controls maintained over the exposure conditions during and after the irradiation of insulating materials with ionizing radiation prior to the determination of radiation-induced changes in physical or chemical properties. This standard specifies a number of potentially significant irradiation conditions as well as various parameters which can influence the radiation-induced reactions under these conditions. The objective of this standard is to emphasize the importance of selecting suitable specimens, exposure conditions and test methods for determining the effect of radiation on appropriately chosen properties. Since many materials are used either in air or in inert environments, standard exposure conditions are recommended for both of these situations. It should be noted that this standard does not consider measurements which are performed during the irradiation. This edition includes the following significant technical changes with respect to the previous edition:
- alignment with standards recently developed by SC 45A as well as with other parts in the IEC 60544 series.

IEC 60493-1:2011 gives statistical methods which may be applied to the analysis and evaluation of the results of ageing tests. It covers numerical methods based on mean values of normally distributed test results. These methods are only valid under specific assumptions regarding the mathematical and physical laws obeyed by the test data. Statistical tests for the validity of some of these assumptions are also given. This standard deals with data from both complete test sets and censored test sets. This standard provides data treatment based on the concept of "data sub-group" as defined in Clause 3. The validity of the coefficients used in the calculation processes to derive statistical parameters of the data groups are described in IEC 60216-1. This second edition cancels and replaces the first edition, published in 1974, and constitutes a technical revision. The main changes with respect to the first edition are that, besides a complete editorial revision, censored data sub-group are considered.

IEC 60544-5:2011 covers ageing assessment methods which can be applied to components based on polymeric materials (e.g. cable insulation and jackets, elastomeric seals, polymeric coatings, gaiters) which are used in environments where they are exposed to radiation. The object of this standard is aimed at providing methods for the assessment of ageing in service. The approaches discussed in the following clauses cover ageing assessment programmes based on condition monitoring (CM), the use of sample deposits in severe environments and sampling of real-time aged components. This second edition cancels and replaces the first edition, published in 2003, and constitutes an editorial revision to align it with standards recently developed by SC 45A as well as with other parts in the IEC 60544 series.

IEC 60505:2011 establishes the basis for estimating the ageing of electrical insulation systems (EIS) under conditions of either electrical, thermal, mechanical, environmental stresses or combinations of these (multifactor stresses). It specifies the principles and procedures that shall be followed, during the development of EIS functional test and evaluation procedures, to establish the estimated service life for a specific EIS. This standard should be used by all IEC technical committees responsible for equipment having an EIS. The contents of the corrigendum of March 2017 have been included in this copy.

IEC/TS 61934:2011(E) is applicable to the off-line electrical measurement of partial discharges (PD) that occur in electrical insulation systems (EIS) when stressed by repetitive voltage impulses generated from electronic power devices. Typical applications are EIS belonging to apparatus driven by power electronics, such as motors, inductive reactors and windmill generators. Excluded from the scope of this technical specification are:
- methods based on optical or ultrasonic PD detection,
- fields of application for PD measurements when stressed by non-repetitive impulse voltages such as lightning impulse or switching impulses from switchgear.
The principal changes with regard to the previous edition concern the addition of:
- an Introduction that provides some background information on the progress being made in the field of power electronics;
- impulse generators;
- PD detection methods;
- a new informative Annex C covering practical experience obtained from round-robin testing (RRT);
- example of noise levels, as shown in new informative Annex D.

IEC 62631-1:2011 gives general guidelines for the determination of dielectric and resistive properties of solid electrical insulating materials.

IEC/TS 62332-1:2011(E) is applicable to EIS containing solid and liquid components where the thermal stress is the dominant ageing factor, without restriction to voltage class. This part specifies a dual-temperature test procedure for the thermal evaluation and qualification of electrical insulation systems (EIS). The following significant technical changes with respect to the previous edition have been made - Modifications have been made based on an extensive test series conducted using this methodology given in the first edition. This included updating expected times and tempertatures to use in order to obtain useful results, as well as making the range of equipment covered broader. The method can now cover electrotechnical devices using different sealing systems, as well as devices using enamel covered wires.

IEC 60212:2010 gives the accepted conditions of exposure time, temperature, atmospheric humidity and liquid immersion for use in testing solid electrical insulating materials. The range is sufficiently wide to enable suitable conditions to be selected so that either of the primary objects, set out below as a) and b), of conditioning can be achieved. These objectives aim to obtain greater reproducibility of test results by:
a) partly counteracting the variations of the properties of the material due to the past history of the test specimens (often known as "normalizing", here called preconditioning), and
b) ensuring uniformity of conditions during the testing.
This standard is not intended to be applied for determining the influence of exposure to certain temperatures and humidity or immersions in liquids, on the properties of a material. Procedures pertaining to the effect of an environment on a material are given in various parts of IEC 60068. The significant technical changes with respect to the previous edition are as follows:
- the scope and normative references have been updated and terms and definitions completely reviewed;
- technical details in Table 2 have been aligned to today's usage.

IEC 60112:2003+A1:2009 Specifies the method of test for the determination of the proof and comparative tracking indices of solidinsulating materials on pieces taken from parts of equipment and on plaques of material using alternating voltages. The standard provides for the determination of erosion when required. Test results cannot be used directly for the evaluation of safe creepage distances when designing electrical apparatus. Has the status of a basic safety publication in accordance with IEC Guide 104. Major changes since the previous edition are the following: The selection of a material for a specific application frequently involves compromises in the levels of the individual properties and test criteria. In the previous edition of IEC 60112 the test criteria required "no burning of the specimen", but this gave rise to two issues:
- difficulties in the identification of burning which includes all types of combustion, e.g. flaming, and smouldering in the situation where scintillations had occurred giving rise in many cases to carbon on the surface of the specimen, and
- a situation in which some product committees had found it necessary to dispense with the "no burning" criterion in the tracking tests which they replaced by flame tests on the final product, thereby giving rise to two types of CTI/PTI with different criteria.
The contents of the corrigenda of June 2003 and October 2003 have been included in this copy. This consolidated version consists of the fourth edition (2003) and its amendment 1 (2009). Therefore, no need to order amendment in addition to this publication.