IEC 62217:2005

INTERNATIONAL IEC
STANDARD 62217
First edition
2005-10
Polymeric insulators for indoor and outdoor use
with a nominal voltage >1 000 V –
General definitions, test methods
and acceptance criteria
Reference number
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INTERNATIONAL IEC
STANDARD 62217
First edition
2005-10
Polymeric insulators for indoor and outdoor use
with a nominal voltage >1 000 V –
General definitions, test methods
and acceptance criteria
 IEC 2005  Copyright - all rights reserved
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– 2 – 62217  IEC:2005(E)
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope and object.6
2 Normative references .6
3 Terms and definitions .7
4 Identification.9
5 Environmental conditions.9
6 Information on transport, storage and installation .10
7 Classification of tests .10
7.1 Design tests .10
7.2 Type tests .10
7.3 Sample tests .10
7.4 Routine tests .11
8 General requirements for insulator test specimens .11
9 Design tests .11
9.1 General .11
9.2 Tests on interfaces and connections of end fittings.11
9.3 Tests on shed and housing material .14
9.4 Tests on the core material .17

Annex A (normative) Wheel test.22
Annex B (normative) Test at multiple stresses .24
Annex C (informative) Difference between the tracking and erosion and accelerated
ageing tests on polymeric insulators .30
Annex D (informative) Recommended application of tests.31
Annex E (informative) Explanation of the concept of classes for the design tests .32

Bibliography.33

Figure 1 – Example of boiling container for the water diffusion test.19
Figure 2 – Examples of test specimen for core material .20
Figure 3 – Electrodes for the voltage test.21
Figure 4 – Voltage test circuit .21
Figure A.1 – Test arrangement of the tracking wheel test.23
Figure B.1 — Typical layout of the test specimens in the chamber and main
dimensions of the chamber .24
Figure B.2 – Multiple stress cycle .27
Figure B.3 – Typical layout of the rain and salt fog spray systems and the xenon lamp .28
Figure B.4 – Spectrum of xenon arc lamp and solar spectrum.28
Figure B.5 – Reference porcelain insulator .29

Table 1 – Normal environmental conditions.9
Table 2 – Initial NaCl content of the water as a function of the specimen dimensions.16

62217  IEC:2005(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
POLYMERIC INSULATORS FOR INDOOR AND OUTDOOR USE
WITH A NOMINAL VOLTAGE >1 000 V –
GENERAL DEFINITIONS, TEST METHODS
AND ACCEPTANCE CRITERIA
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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International Standard IEC 62217 has been prepared by IEC technical committee 36:
Insulators.
The text of this standard is based on the following documents:
FDIS Report on voting
36/244/FDIS 36/245/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – 62217  IEC:2005(E)
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

62217  IEC:2005(E) – 5 –
INTRODUCTION
Polymeric insulators consist either of one insulating material (resin insulators) or two or
several insulating materials (composite insulators). The insulating materials are generally
cross-linked organic materials synthesized from carbon or silicon chemistry and form the
insulating body. Insulating materials can be composed from organic materials containing
various inorganic and organic ingredients, such as fillers and extenders. End fittings are often
used at the ends of the insulating body to transmit mechanical loads. Despite these common
features, the materials used and the construction details employed by different manufacturers
may be widely different.
Some tests have been grouped together as "design tests", to be performed only once for
insulators of the same design. The design tests are intended to eliminate insulator designs,
materials or manufacturing technologies which are not suitable for high-voltage applications.
The influence of time on the electrical properties of the complete polymeric insulator and its
components (core material, housing, interfaces, etc.) has been considered in specifying the
design tests in order to ensure a satisfactory life-time under normal operating and
environmental conditions.
Pollution tests, according to IEC 60507 or IEC 61245, are not included in this International
Standard, their applicability to composite insulators not having been proven. The results of
such pollution tests performed on insulators made of polymeric materials do not correlate with
experience obtained from service. Specific pollution tests for polymeric insulators are still
under consideration.
The tracking and erosion tests given in this standard are considered as screening tests
intended to reject materials or designs which are inadequate. These tests are not intended to
predict long-term performance for insulator designs under cumulative service stresses. For
more information, see Annex C.
Composite insulators are used in both a.c. and d.c. applications. In spite of this fact a specific
tracking and erosion test procedure for d.c. applications as a design test has not yet been
defined and accepted. The 1 000 h a.c. tracking and erosion test described in this standard is
used to establish a minimum requirement for the tracking resistance of the housing material.
IEC Guide 111 has been followed during preparation of this standard wherever possible.

– 6 – 62217  IEC:2005(E)
POLYMERIC INSULATORS FOR INDOOR AND OUTDOOR USE
WITH A NOMINAL VOLTAGE >1 000 V –
GENERAL DEFINITIONS, TEST METHODS
AND ACCEPTANCE CRITERIA
1 Scope and object
This International Standard is applicable to polymeric insulators whose insulating body
consists of one or various organic materials. Polymeric insulators covered by this standard
include both solid core and hollow insulators. They are intended for use on overhead lines
and in indoor and outdoor equipment with a rated voltage greater than 1 000 V.
The object of this standard is
– to define the common terms used for polymeric insulators,
– to prescribe common test methods for design tests on polymeric insulators,
– to prescribe acceptance or failure criteria, if applicable,
– to give recommendations for polymeric insulator test standards or product standards,
complemented by specific requirements as needed.
These tests, criteria and recommendations are intended to ensure a satisfactory life-time
under normal operating and environmental conditions (see Clause 5).
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60060-1, High-voltage test techniques – Part 1: General definitions and test requirements
IEC 60068-2-11, Basic environmental testing procedures – Part 2: Tests, Test KA: Salt mist
IEC 60507, Artificial pollution tests on high-voltage insulators to be used on a.c. systems
IEC 60695-11-10, Fire hazard testing – Part 11-10: Test flames – 50 W horizontal and vertical
flame test methods
IEC 60721-1, Classification of environmental conditions – Part 1: Environmental parameters
and their severities
IEC 60815, Guide for the selection of insulators in respect of polluted conditions
IEC Guide 111, Electrical high-voltage equipment in high-voltage substations – Common
recommendations for product standards
ISO 868, Plastics and ebonite – Determination of indentation hardness by means of a
durometer (Shore hardness)
ISO 4287, Geometrical Product Specifications (GPS) – Surface texture: Profile method –
Terms, definitions and surface texture parameters
ISO 4892-1, Plastics – Methods of exposure to laboratory light sources – Part 1: General
Guidance
ISO 4892-2, Plastics – Methods of exposure to laboratory light sources – Part 2: Xenon-arc
sources
62217  IEC:2005(E) – 7 –
ISO 4892-3, Plastics – Methods of exposure to laboratory light sources – Part 3: Fluorescent
UV lamps
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
polymeric insulator
insulator whose insulating body consists of at least one organic based material.
NOTE Coupling devices may be attached to the ends of the insulating body
NOTE Polymeric insulators are also known as non-ceramic insulators.
[IEV 471-01-13]
3.2
resin insulator
polymeric insulator whose insulating body consists of a solid shank and sheds protruding from
the shank made from only one organic based housing material (e.g. cycloaliphatic epoxy)
3.3
composite insulator
insulator made of at least two insulating parts, namely a core and a housing equipped with
metal fittings
NOTE Composite insulators, for example, can consist either of individual sheds mounted on the core, with or
without an intermediate sheath, or alternatively, of a housing directly moulded or cast in one or several pieces on
to the core.
[IEV 471-01-02]
3.4
core (of an insulator)
central insulating part of an insulator which provides the mechanical characteristics
NOTE The housing and sheds are not part of the core.
[IEV 471-01-03]
3.5
insulator trunk
central insulating part of an insulator from which the sheds project.
NOTE Also known as shank on smaller insulators.
[IEV 471-01-11]
3.6
housing
external insulating part of composite insulator providing necessary creepage distance and
protecting core from environment
NOTE An intermediate sheath made of insulating material may be part of the housing.
[IEV 471-01-09]
3.7
shed (of an insulator)
insulating part, projecting from the insulator trunk, intended to increase the creepage
distance. The shed can be with or without ribs
[IEV 471-01-15]
– 8 – 62217  IEC:2005(E)
3.8
creepage distance
shortest distance or the sum of the shortest distances along the surface on an insulator
between two conductive parts which normally have the operating voltage between them
NOTE 1 The surface of cement or of any other non-insulating jointing material is not considered as forming part of
the creepage distance.
NOTE 2 If a high resistance coating is applied to parts of the insulating part of an insulator, such parts are
considered to be effective insulating surfaces and the distance over them is included in the creepage distance.
[IEV 471-01-04]
3.9
arcing distance
shortest distance in air external to the insulator between the metallic parts which normally
have the operating voltage between them
[IEV 471-01-01]
3.10
interfaces
surface between the different materials
NOTE Various interfaces occur in most composite insulators, e.g.
− between housing and end fittings,
− between various parts of the housing, e.g. between sheds, or between sheath and sheds,
− between core and housing.
3.11
end fitting
integral component or formed part of an insulator intended to connect it to a supporting
structure, or to a conductor, or to an item of equipment, or to another insulator
NOTE Where the end fitting is metallic, the term “metal fitting” is normally used.
[IEV 471-01-06, modified]
3.12
connection zone
zone where the mechanical load is transmitted between the insulating body and the end fitting
3.13
coupling (of an insulator)
part of the end fitting which transmits load to the hardware external to the insulator
3.14
tracking
process which forms irreversible degradation by formation of conductive paths (tracks)
starting and developing on the surface of an insulating material
NOTE These paths are conductive even under dry conditions.
3.15
erosion
irreversible and non-conducting degradation of the surface of the insulator that occurs by loss
of material which can be uniform, localized or tree-shaped
NOTE Light surface traces, commonly tree-shaped, can occur on composite insulators as on ceramic insulators,
after partial flashover. These traces are not considered to be objectionable as long as they are non-conductive.
When they are conductive they are classified as tracking

62217  IEC:2005(E) – 9 –
3.16
crack
any internal fracture or surface fissure of depth greater than 0,1 mm
3.17
puncture (of an insulator)
permanent loss of dielectric strength due to a disruptive discharge passing through the solid
insulating material of an insulator
[IEV 471-01-14]
4 Identification
The manufacturer’s drawing shall show the relevant dimensions and information necessary for
identifying and testing the insulator in accordance with this standard and the applicable IEC
product standard(s). The drawing shall also show applicable manufacturing tolerances.
Each insulator shall be marked with the name or trade mark of the manufacturer and the year
of manufacture. In addition, each insulator shall be marked with the rated characteristics
specified in the relevant IEC product standards. These markings shall be legible, indelible and
their fixings (if any) weather- and corrosion-proof.
5 Environmental conditions
The normal environmental conditions to which insulators are submitted in service are defined
according to Table 1.
When special environmental conditions prevail at the location where insulators are to be put
in service, they shall be specified by the user by reference to IEC 60721-1.
Table 1 – Normal environmental conditions
Condition Indoor insulation Outdoor insulation
Does not exceed 40 °C and its average value measured over a period of
Maximum ambient air temperature
24 h does not exceed 35 °C
Minimum ambient air temperature –25 °C –40 °C
Negligible vibration due to causes external to the insulators or to earth
Vibration
a
tremors
b
Solar radiation To be neglected Up to a level of 1 000 W/m
Pollution by dust, smoke, corrosive
No significant pollution by dust,
gases, vapours or salt may occur.
Pollution of the ambient air smoke, corrosive and/or flammable
Pollution does not exceed “heavy” as
gases, vapours, or salt
defined in IEC 60815
The average value of the relative
humidity, measured over a period of
24 h, does not exceed 95 %;
Humidity measured over a period of one
month, does not exceed 95 %. For
these conditions, condensation may
occasionally occur
a
Vibration due to external causes can be dealt with in accordance to IEC 60721-1.
b
Details of solar radiation are given in IEC 60721-1.

– 10 – 62217  IEC:2005(E)
6 Information on transport, storage and installation
Manufacturers of insulators shall provide appropriate instructions and information covering
general conditions during transport, storage and installation of the insulators. These
instructions can include recommendations for cleaning or maintenance.
7 Classification of tests
The tests are divided into four groups as follows:
7.1 Design tests
The design tests are intended to verify the suitability of the design, materials and method of
manufacture (technology).
A polymeric insulator design is generally defined by
– materials of the core, housing and manufacturing method,
– material of the end fittings, their design and method of attachment,
– layer thickness of the housing over the core (including a sheath where used).
Additional parameters defining design may be given in the relevant product standard.
When changes in the design of a polymeric insulator occur, re-qualification shall be carried
out according to the requirements of the relevant product standard. Typically, only part of the
tests are repeated. A survey of the tests is given in Annex D.
When a polymeric insulator is submitted to the design tests, it becomes a parent insulator for
a design class and the results shall be considered valid for the whole class. This tested
parent insulator defines a design class of insulators which have the following characteristics:
a) same materials for the core and housing and same manufacturing method;
b) same material as for the end fittings, same design and same method of attachment;
c) same or greater minimum layer thickness of housing over the core (including a sheath
where used).
Additional parameters to define a class of design may be given in the relevant product
standard.
7.2 Type tests
The type tests are intended to verify the main characteristics of a polymeric insulator, which
depend mainly on its shape and size. Type tests shall be applied to polymeric insulators
belonging to an already qualified design class. The type tests shall be repeated only when the
type of polymeric insulator is changed. The parameters defining a type of polymeric insulator
are given in the relevant product standard.
The applicable type tests are given in the relevant product standard.
7.3 Sample tests
The sample tests are intended to verify the characteristics of polymeric insulators which
depend on the quality of manufacture and on the materials used. They are made on insulators
taken at random from lots offered for acceptance.
The applicable sample tests are given in the relevant product standard.

62217  IEC:2005(E) – 11 –
7.4 Routine tests
These tests are intended to eliminate polymeric insulators with manufacturing defects. They
are carried out on every insulator to be supplied.
The applicable routine tests are given in the relevant product standard.
8 General requirements for insulator test specimens
Insulator test specimens for tests of polymeric insulators shall be checked prior to tests:
• for correct assembly, for example by applying the mechanical routine test specified in the
relevant product standard,
• by visual examination according to the relevant product standard;
• for conformance of dimensions with the actual drawing.
For dimensions d without tolerances the following tolerances are acceptable:
• ± (0,04 x d + 1,5) mm when d ≤ 300 mm;
• ± (0,025 x d + 6) mm when d > 300 mm with a maximum tolerance of 50 mm.
The measurement of creepage distances shall be related to the design dimensions and
tolerances as determined from the insulator drawing, even if this dimension is greater than the
value originally specified. When a minimum creepage is specified, the negative tolerance is
also limited by this value.
In the case of insulators with creepage distance exceeding 3 m, it is allowed to measure a
short section around 1 m long of the insulator and to extrapolate.
The housing colour of the test specimens shall be approximately as specified in the drawing.
The number of test specimens, their selection and dimensions are specified in the relevant
clauses of this standard or in the relevant test standards.
9 Design tests
9.1 General
The following tests are normally classified as design tests, unless otherwise specified in the
relevant product standard.
The design tests shall be performed only once according to the relevant product standard and
the results shall be recorded in a test report.
Each test (9.2, 9.3, 9.4 and 9.5) can be performed independently on new test specimens,
where appropriate, according to the test sequence given in the relevant test standard. The
polymeric insulator of a particular design shall be deemed qualified only when all insulators or
test specimens pass all the design tests specified in the relevant product standard.
9.2 Tests on interfaces and connections of end fittings
The test sequence consists of the following:
• reference dry power frequency test (9.2.3);
• pre-stressing (9.2.4);
• verification test (9.2.6).
– 12 – 62217  IEC:2005(E)
9.2.1 Test specimens
For this series of tests, insulators assembled on the production line shall be selected. The
number of specimens and their dimensions shall be in accordance with the relevant product
standard. They shall be checked and tested as indicated in Clause 8.
If the manufacturer only has facilities to produce insulators with one or more dimensions
smaller than indicated in the relevant product standard, the design tests may be performed on
insulators of those dimensions available to him, however the results are only valid for other
insulators of the same design class up to the dimensions tested.
9.2.2 Reference voltage and temperature for verification tests
For time or economic reasons, the reference dry power frequency test in 9.2.3 at the
beginning of the test sequence may be omitted if an additional reference test specimen is
used with properties as indicated in 9.2.1. The dry power frequency voltages after pre-
stressing according to 9.2.6.3 and the shank temperature shall be compared either with the
values of the reference test specimen or with the voltages determined prior to pre-stressing. It
is clearly understood that the reference test specimen shall be not submitted to pre-stressing.
9.2.3 Reference dry power frequency test
The reference dry power frequency external flashover voltage shall be determined by
averaging five flashover voltages, determined according to IEC 60060-1, on the test
specimens or on the reference test specimen. This average flashover voltage shall be
corrected to standard conditions in accordance with IEC 60060-1. The flashover voltage shall
be obtained by increasing the voltage linearly from zero to flashover within 1 min.
9.2.4 Product specific pre-stressing
The test specimens shall be subjected to pre-stressing (e.g. thermal-mechanical) according to
the relevant product standard.
9.2.5 Water immersion pre-stressing
The specimens shall be kept immersed in a vessel, in boiling de-ionized water with 0,1 % by
weight of NaCl, for 42 h. Alternatively, tap water may be used with salt added to obtain a
conductivity of 1 750 µS/cm ± 80 µS/cm at 20 °C. For a different water temperature, the
conductivity correction as given in IEC 60507, Clause 7 shall be applied.
At the end of boiling, the specimens are allowed to cool and shall remain in water until the
verification tests start in the following sequence. If transport is necessary in this period, the
wet insulators may be put in sealed plastic bags or another suitable container for a maximum
of 12 h.
9.2.6 Verification tests
The time interval between the following individual tests shall be such that the verification tests
are completed within 48 h.
9.2.6.1 Visual examination
The housing of each specimen is inspected visually. No cracks are permissible.

62217  IEC:2005(E) – 13 –
9.2.6.2 Steep-front impulse voltage test
9.2.6.2.1 Procedure
The test specimens shall be fitted with sharp-edged electrodes (consisting of clips, e.g. made
of a copper strip approximately 20 mm wide and less than 1 mm thick). These electrodes are
fitted firmly around the housing between sheds so positioned to form sections of axial length
of about 500 mm or smaller. The voltage shall be applied to the original metal fittings in case
of insulators with a distance between end fittings smaller than, or equal to, 500 mm.
An impulse voltage with a steepness of at least 1 000 kV/µs shall be applied between two
neighbouring electrodes or between the metal fitting and the neighbouring electrode,
respectively. Each section shall be stressed individually with 25 impulses of positive and 25
impulses of negative polarity. Means shall be employed to prevent internal flashover of hollow
insulators.
9.2.6.2.2 Acceptance criteria
Each impulse shall cause external flashover between the electrodes. No puncture of any part
of the insulator shall occur.
9.2.6.3 Dry power frequency voltage test
9.2.6.3.1 Procedure
Before commencing the flashover test, the shank temperature on all test specimens shall be
determined (reference temperature).
The dry power frequency voltage shall be determined by averaging five flashover voltages on
each specimen. The average flashover voltage shall be corrected to normal standard
atmospheric conditions in accordance with IEC 60060-1. The flashover voltage shall be
obtained by increasing the voltage linearly from zero within 1 min.
Using the same method, determine the value of the reference flashover voltage using an
additional reference test specimen, if available.
The test specimens and the reference test specimen, if applicable, shall then be continuously
subjected for 30 min to 80 % of the reference flashover voltage.
The temperature of the housing between the sheds of each test specimen and of the
reference insulator, if applicable, shall be measured at three places along or around the
insulator immediately after the removal of the test voltage.
9.2.6.3.2 Acceptance criteria
The flashover voltage of each of the test specimens shall be greater than or equal to 90 % of
the reference flashover voltage or the flashover voltage of the reference test specimen,
respectively.
No puncture of any part of the insulator shall occur and the maximum temperature rise of
each insulator housing between the sheds with respect to the temperature of the reference
test specimen shall be less than 10 K. In cases where there is no reference test specimen
then the maximum temperature rise shall be less than 20 K compared to the reference
temperature determined prior to the power frequency tests.

– 14 – 62217  IEC:2005(E)
9.3 Tests on shed and housing material
9.3.1 Hardness test
9.3.1.1 Procedure
Two specimens of the housing material of a size, shape and thickness appropriate for the
hardness measurement method given in ISO 868 shall be taken from the housing of two
insulators. If the shed shape or thickness is inappropriate, then samples may be made
separately using the same manufacturing process and parameters.
Measure and record the ambient temperature and the hardness of the two samples in
accordance with ISO 868 with a Shore A or D durometer, as appropriate.
The samples shall then be kept immersed in boiling water as defined in 9.2.5 for 42 h. The
boiling container shown in Figure 1 is suitable for this boiling.
At the end of the boiling period, the samples shall be allowed to cool and, within 3 h, their
hardness shall be measured again at the same temperature as that of the pre-boiling
measurements ±5 K.
9.3.1.2 Acceptance criteria
The hardness of each specimen shall not change from the pre-boiled value by more
than ±20 %.
9.3.2 Accelerated weathering test
9.3.2.1 Procedure
Select three specimens of shed and housing materials for this test (with markings included, if
applicable).
The insulator housing material shall be subjected to a 1 000 h UV light test using one of the
following test methods. Markings on the housing, if any, shall be directly exposed to UV light:
• Xenon-arc methods: ISO 4892-1 and ISO 4892-2, using method A without dark periods
standard spray cycle black-standard/black panel temperatures of 65 °C an irradiance of
around 550 W/m
• Fluorescent UV method: ISO 4892-1 and ISO 4892-3, using type I fluorescent UV lamp
exposure method 1 or 2.
NOTE An increased duration for the fluorescent UV test method is under consideration by CIGRE SC D1.
9.3.2.2 Acceptance criteria
After the test, markings on shed or housing material shall be legible; surface degradations
such as cracks and raised areas are not permitted.
In case of doubt concerning such degradation, two surface roughness measurements shall be
made on each of the three specimens. The roughness, R as defined in ISO 4287, shall be
z
measured along a sampling length of at least 2,5 mm. R shall not exceed 0,1 mm.
z
NOTE ISO 3274 give details of surface roughness measurement instruments.

62217  IEC:2005(E) – 15 –
9.3.3 Tracking and erosion test
Two standard tests (1 000 h salt fog test, wheel test (Annex A)) are described. A third test
method includes more multiple stresses (Annex B). One of the three test methods shall be
chosen to verify the resistance of an insulator design to the stress of electrical discharge
activity.
9.3.3.1 1 000 h salt fog test
9.3.3.1.1 Procedure
9.3.3.1.1.1 General
The test is a time-limited continuous test in salt fog at constant power-frequency voltage.
9.3.3.1.1.2 Test chamber
The test is carried out in a moisture-sealed corrosion-proof chamber, the volume of which
3 2
shall not exceed 15 m . An aperture of not more than 80 cm shall be provided for the natural
exhaust air.
9.3.3.1.1.3 Fog generation
A turbo sprayer (room humidifier) of constant spraying capacity shall be used as a water
atomizer forming water droplets of a size of 5 µm to 10 µm. Alternatively, nozzles producing
water droplets of the same size may be used. The IEC 60507 salt fog spray nozzles are not
suitable for this test. The sprayer or nozzles are mounted close to the bottom of the chamber
and spray upwards towards the roof of the chamber. The fog shall fill up the chamber and not
be directly sprayed on to the test specimen. Salt water prepared from NaCl and de-ionized
water shall be supplied to the sprayer (see Table 2). The fog intensity and uniformity shall be
maintained in the specimen’s exposure zone.
9.3.3.1.1.4 Fog calibration
The calibration shall be carried out at the start of the test.
2 2
At least two clean collecting receptacles with a collecting area of 8 000 mm ± 2 000 mm and
a maximum height of 100 mm each are placed as close as practical to the position of the ends
of the test object. The receptacles shall be positioned in such a way that they are not shielded
by the test specimens and to avoid dripping from the construction elements of the chamber or
another source.
They shall collect between 1,5 ml and 2,0 ml of precipitation per hour (corrected to 8 000 mm
collecting area) averaged over a minimum period of 16 h according to IEC 60068-2-11.
NOTE The flow rate necessary to obtain such precipitation (typically of the order of 0,3 l/m h) should be noted.
(The water flow rate is defined in litres per hour and per cubic meter of the test chamber volume.) Subsequently
during the test, the flow rate should be checked at least every 100 h and remain within ±25 % of the initial value.
It is not permitted to re-circulate the water.
9.3.3.1.1.5 Test specimens
Two test insulators of identical design with a creepage distance between 500 mm and 800 mm
shall be taken from the production line. If such insulators cannot be taken from the production
line, special test specimens shall be made from other insulators so that the creepage distance
falls between the given values. These special test specimens shall be fitted with standard
production end fittings.
– 16 – 62217  IEC:2005(E)
The test specimens shall be cleaned with de-ionized water before starting the test. One test
specimen shall be tested mounted horizontally (at approximately half the height of the
chamber) and the second shall be mounted vertically. There shall be a clearance of at least
400 mm between parallel test specimens and between test specimens and the roof, the walls
and the floor.
NOTE Up to two pairs of test specimens can be tested simultaneously.
9.3.3.1.1.6 Test voltage
The test voltage in kilovolts is adjusted to the actual creepage distance of the test specimens
determined by dividing the creepage distance in millimetres by 34,6 (equal to a specific
creepage distance of 20 mm/kV). The test circuit when loaded with a continuous resistive
current of 250 mA (r.m.s.) during 1 s on the high voltage side shall experience a maximum
voltage drop of 5 %. The protection level shall be set at 1 A (r.m.s.).
9.3.3.1.1.7 Test conditions
Duration of the test: 1 000 h.
Weekly interruptions of the test for inspection purposes, each of these not exceeding 1 h are
permissible. Interruption periods shall not be counted in the test duration.
One longer interruption up to 60 h is allowed. An additional testing time of three times the
duration of the interruption period shall be added. The final test report shall include all details
of interruptions.
Ambient temperature: 20 °C ± 5 K .
Initial salt content of the water: According to Table 2.
Table 2 – Initial NaCl content of the water as a function of
the specimen dimensions
Initial NaCl content of water
Shank diameter
kg/m
mm
l/p >3
l/p ≤3
< 50 8 ± 0,4 4 ± 0,2
50 to 150 4 ± 0,2 2 ± 0,1
> 150 2 ± 0,1 1 ± 0,1
l/p is the creepage distance divided by the arcing distance.

NOTE For insulators with longer creepage per length, the initial NaCl content is reduced in order to avoid
flashovers during the 1 000 h test. This reduction in salinity is not regarded as decreasing the severity of the
tracking and erosion test but chosen to avoid unnecessary interruptions of the procedure.

If more than one flashover occurs at the initial NaCl content, the test shall be re-started at a
halved value of the NaCl content. The insulators are washed by tap water and the test re-
started within 8 h (interruption times shall not be counted as part of the test duration). This
may be repeated until interruptions no longer occur. The application of any of the above
measures shall be noted.
The numbers of flashovers and trip-outs shall be recorded and noted in the test report.

62217  IEC:2005(E) – 17 –
9.3.3.1.1.8 Acceptance criteria
The test specimens of identical design shall be assessed together. The test is regarded as
passed if, on both test specimens:
• no tracking occurs;
• for composite insulators, erosion depth is less than 3 mm and does not reach the core, if
applicable;
• for resin insulators, erosion depth is less than 3 mm;
• no shed, housing or interface is punctured.
9.3.4 Flammability test
9.3.4.1 Procedure
This test is intended to check the housing material for ignition and self-extinguishing
properties.
The test specimen and procedure shall be according to IEC 60695-11-10. Sample thickness
shall be 3 mm.
9.3.4.2 Acceptance criteria
The test is passed if the test specimen belongs to category HB40 and V0. The acceptance
category shall be recorded.
NOTE The resistance to flammability is determined by intrinsic material properties and the design of the
insulation. The minimum requirement is based on the fact that the insulation material will not continue burning after
ignition, e.g. by a power arc or due to electrical discharges. Amendment 1(1995) to the first edition of
IEC 61109:1992 requires the flammability classification for housing materials, as part of the design tests,
according to method FV of the first edition of IEC 60707:1981 which has since been replaced by Method B
according to IEC 60695-11-10. The horizontal burning test HB in IEC 60707:1981 could not be carried out on thin
flexible specimens such as polymer insulator housing material. Method A of IEC 60695-11-10 is now available and
allows testing of such flexible specimens. It is known that the minimum requirement, for the purposes of this
standard, is met by materials satisfying category V0. Presently it is unknown whether this applies also to materials
which only satisfy HB4
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