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SIST EN 50483-6:2009
01-julij-2009
Zahteve za preskušanje pribora za nizkonapetostne izolirane nadzemne kable - 6.
del: Okoljsko preskušanje
Test requirements for low voltage aerial bundled cable accessories -- Part 6:
Environmental testing
Prüfanforderungen für Bauteile für isolierte Niederspannungsfreileitungen – Teil 6:
Umweltprüfungen
Prescriptions relatives aux essais des accessoires pour réseaux aériens basse tension
torsadés -- Partie 6: Essais d’environnement
Ta slovenski standard je istoveten z: EN 50483-6:2009
ICS:
29.240.20 Daljnovodi Power transmission and
distribution lines
SIST EN 50483-6:2009 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 50483-6:2009
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SIST EN 50483-6:2009
EUROPEAN STANDARD
EN 50483-6
NORME EUROPÉENNE
January 2009
EUROPÄISCHE NORM
ICS 29.240.20
English version
Test requirements for low voltage aerial bundled cable accessories -
Part 6: Environmental testing
Prescriptions relatives aux essais Prüfanforderungen für Bauteile für isolierte
des accessoires pour réseaux aériens Niederspannungsfreileitungen -
basse tension torsadés - Teil 6: Umweltprüfungen
Partie 6: Essais d’environnement
This European Standard was approved by CENELEC on 2008-12-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: avenue Marnix 17, B - 1000 Brussels
© 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50483-6:2009 E
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SIST EN 50483-6:2009
EN 50483-6:2009 – 2 –
Foreword
This European Standard was prepared by a sub-group of WG 11 of the Technical Committee
CENELEC TC 20, Electric cables.
The text of the draft was submitted to the formal vote and was approved by CENELEC as
EN 50483-6 on 2008-12-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2009-12-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2011-12-01
This is Part 6 of CENELEC standard EN 50483 “Test requirements for low voltage aerial
bundled cable accessories”, which has six parts:
– Part 1: Generalities;
– Part 2: Tension and suspension clamps for self supporting system;
– Part 3: Tension and suspension clamps for neutral messenger system;
– Part 4: Connectors;
– Part 5: Electrical ageing test;
– Part 6: Environmental testing.
__________
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Contents
1 Sc op e . . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Symbols . 5
5 Marking . . 5
6 (Spare) . 5
7 (Spare) . 5
8 Type tests . 6
8.1 Number of test samples and number of cycles . 6
8.2 Requir em ents . 6
8.3 Cl e a n i n g . 6
8.4 Corrosion ageing tests . 6
8.5 Climatic ageing test . 10
Annex A (informative) Salt mist and gas atmosphere corrosion test justification . 18
Annex B (informative) Example of specific reaction to obtain sulphur dioxide . 19
Annex C (informative) Climatic areas . 20
Annex D (informative) Test equipment . 21
Bibliography . 24
Figures
Figure 1 – Suggested arrangement for connections – Optional immersion test Method 1 . 9
Figure 2 – Informative diagram of the conditioning cycle – Weekly cycle . 15
Figure 3 – Temperature – Radiation – Time relationships . 17
Figure D.1 – Typical test arrangement . 21
Tables
Table 1 – Quantities for acid solution components . 10
Table 2 – Spectral energy distribution and permitted tolerances . 17
Table C.1 – Climatic conditions – Appropriate tests . 20
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SIST EN 50483-6:2009
EN 50483-6:2009 – 4 –
1 Scope
EN 50483 series applies to overhead line fittings for tensioning, supporting and connecting
aerial bundled cables (ABC) of rated voltage U /U (U ): 0,6/1 (1,2) kV.
0 m
The objective is to provide a method of testing the suitability of accessories when used under
normal operating conditions with low voltage aerial bundled cables complying with HD 626.
This Part 6 defines the environmental tests in particular the climatic and corrosion ageing
tests. The objective of these tests is to predict the behaviour of ABC accessories when
subjected to sun radiation, to weather conditions (humidity, spraying water, heat, cold) and
pollution. EN 50483-1, EN 50483-2, EN 50483-3 and EN 50483-4 specify which type tests
included in this part of the standard are needed.
Climate differs across Europe and in order to meet the differing geographic climatic conditions
it is necessary to provide a range of tests to meet these variations. A range of optional,
additional tests is provided to meet the varying climatic needs and these should be agreed
between the customer and the supplier (see Annex C).
NOTE This European Standard does not invalidate existing approvals of products achieved on the basis of
national standards and specifications and/or the demonstration of satisfactory service performance. However,
products approved according to such national standards or specifications cannot directly claim approval to this
European Standard. It may be possible, subject to agreement between supplier and purchaser, and/or the relevant
conformity assessment body, to demonstrate that conformity to the earlier standard can be used to claim
conformity to this standard, provided an assessment is made of any additional type testing that may need to be
carried out. Any such additional testing that is part of a sequence of testing cannot be done separately.
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.
EN 50483 series, Test requirements for low voltage aerial bundled cable accessories
EN 60068-2-5, Environmental testing – Part 2: Tests – Test Sa: Simulated solar radiation at
ground level (IEC 60068-2-5)
EN 60068-2-9:1999, Environmental testing – Part 2: Tests – Guidance for solar radiation
testing (IEC 60068-2-9:1975 + A1:1984)
EN 60068-2-11:1999, Environmental testing – Part 2: Tests – Test Ka: Salt mist
(IEC 60068-2-11:1981)
EN ISO 3231, Paints and varnishes – Determination of resistance to humid atmospheres
containing sulfur dioxide (ISO 3231)
IEC 60050-461, International Electrotechnical Vocabulary (IEV) – Part 461: Electric cables
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-461 and the
following apply.
3.1
aerial bundled cable (ABC)
aerial cable consisting of a group of insulated conductors which are twisted together
including, or not, a non insulated conductor
[IEV 461-08-02, modified]
NOTE The terms bundled conductors, bundled cables, bundled cores, conductor bundles and bundle could be
used as equivalent to the term aerial bundled cable (ABC).
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3.2
aerial-insulated-cable
insulated cable designed to be suspended overhead and outdoors
[IEV 461-08-01]
3.3
conductor (of a cable)
part of a cable which has the specific function of carrying current
[IEV 461-01-01]
3.4
core
assembly comprising conductor and its own insulation
[IEV 461-04-04, modified]
3.5
fixture (or fitting)
device for attaching ABC tension or/and suspension clamps to a pole or to a wall
3.6
insulation (of a cable)
insulating materials incorporated in a cable with the specific function of withstanding voltage
[IEV 461-02-01]
3.7
type test
test required to be made before supplying a type of material covered by this standard on a
general commercial basis, in order to demonstrate satisfactory performance characteristics to
meet the intended application
NOTE These tests are of such a nature that, after they have been made, they need not be repeated unless
changes are made to the accessory materials, design or type of manufacturing process which might change the
performance characteristics.
4 Symbols
λ and λ wavelength of UV light source
1 2
E mean energy received by the samples
m
E radiated energy of the lamp
n number of cycles (defined in appropriate part of this standard)
θ temperature measured by the black standard thermometer
θ temperature of the chamber
E
5 Marking
See Clause 6 of EN 50483-1.
6 (Spare)
7 (Spare)
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EN 50483-6:2009 – 6 –
8 Type tests
8.1 Number of test samples and number of cycles
The number of samples and number of cycles for each of the following tests are included in
each relevant part of EN 50483.
8.2 Requirements
The requirements for the following tests shall be as given in the relevant parts of this standard.
8.3 Cleaning
On completion of the environmental tests, and between different environmental tests when
carried out as a sequence, the samples shall, unless otherwise specified, be cleaned using
running tap water for 5 min to 10 min and then by using demineralised water for the same
period. The temperature of the water shall not exceed 35 °C. The samples shall be dried
either by shaking by hand or using air blast to remove droplets of water.
8.4 Corrosion ageing tests
These tests shall be carried out when the products contain metallic parts (or parts protected
with a metallic coating), which are exposed to the atmosphere.
A justification of the tests is given in Annex A.
8.4.1 Salt mist test
8.4.1.1 Principle
This test exposes samples to a neutral salt spray (concentration of NaCl: 5 %).
8.4.1.2 Test equipment
The test equipment is defined in Clause 3 of EN 60068-2-11:1999.
8.4.1.3 Test arrangement
The preparation and use of the salt solution is defined in Clause 4 of EN 60068-2-11:1999.
8.4.1.4 Procedure
The test procedure is defined in Clause 7 of EN 60068-2-11:1999.
The connectors or accessories shall be installed as defined in the relevant parts of EN 50483.
The cycle duration prescribed, in accordance with EN 60068-2-11:1999, 7.6 shall be 7 days.
No cleaning of the samples shall be carried out between cycles.
8.4.1.5 Test reports
The test report shall include the duration of exposure and the concentration and pH of the salt
solution.
8.4.2 Gas atmosphere tests
NOTE 1 Two methods of testing are provided to meet the requirements of the gas atmosphere test. The first,
Method 1, is based on the test procedure that has been used for many years in some countries. These countries
have gained experience of both the procedures and outcomes of the test. The second, Method 2 is provided as an
alternative as it requires a less complicated test environment and is based on ASTM G85.
NOTE 2 This test may be necessary for accessories that are used in areas subjected to heavy industrial pollution.
8.4.2.1 Gas atmosphere test (Method 1)
A justification of the tests is given in Annex A.
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8.4.2.1.1 Principle
This test exposes samples to a humidity-saturated atmosphere rich with sulphur dioxide
(initial concentration SO : 0,066 7 % (667 parts per million by volume)) with defined
2
conditions of temperature and pressure.
8.4.2.1.2 Test equipment
The samples and supports shall be installed in a hermetic test chamber, with a
humidity-saturated atmosphere in the presence of sulphur dioxide.
This test chamber shall be made of inert material. The test shall be made in accordance with
EN ISO 3231.
8.4.2.1.3 Preparation of SO atmosphere
2
After closing the chamber, sulphur dioxide (concentration = 0,066 7 %) shall be introduced
from either a gas bottle or using a specific reaction in the chamber as described in Annex B.
8.4.2.1.4 Procedure
Each period, or basic module, shall comprise a weekly sequence.
7 cycles of 24 h (168 h total), each cycle includes an 8 h exposure with saturated humidity
and high sulphur dioxide atmosphere (a total exposure of 56 h), and a 16 h exposure at the
laboratory atmosphere (a total exposure of 112 h).
NOTE Exposure to laboratory atmosphere may be achieved by opening the chamber door. It is the intention of
this phase to allow clean air to circulate around the test samples.
During the 8 h period, the temperature is raised to (40 ± 3) °C. During the 16 h period the
chamber remains at ambient temperature and finally the water and sulphur dioxide
atmosphere is renewed to the concentration as specified in 8.4.2.1.3.
8.4.2.1.5 Cleaning
When the specimens are exposed successively to a neutral salt spray and then to a humidity
saturated atmosphere with sulphur dioxide, the procedure shall be
- 7 cycles of 24 h in salt,
- no cleaning,
- 7 cycles of 24 h in sulphur dioxide,
- cleaning in accordance with 8.3.
8.4.2.2 Gas atmosphere test (Method 2)
8.4.2.2.1 Procedure
The test samples shall be subjected to a cyclic corrosion test consisting of 1 h period of
drying and 1 h period of fog. The test shall consist of 500 cycles (1 000 h). The fog period
shall be at ambient temperature, while the drying time shall be at a higher temperature.
NOTE Experience indicates that longer cycle times may produce slower degradation.
8.4.2.2.2 Test equipment
The apparatus for salt spray (fog) testing consists of a fog chamber, a salt solution reservoir,
a supply of suitable conditioned compressed air, one or more atomising nozzles, specimen
supports, provision for heating the chamber, and necessary means of control. The size and
detailed construction of the cabinet are optional, provided the conditions obtained meet the
requirements of this standard. The material of construction shall be such that it will not be
affected by the corrosiveness of the fog. The chamber shall be designed so that drops of
solution that accumulate on the ceiling or cover of the chamber do not fall on the specimen
being tested. The nozzle or nozzles shall be directed so that none of the spray can impinge
directly on the test specimen.
The solution shall not be recycled.
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8.4.2.2.3 Atomisation and quantity of fog
At least two clean fog collectors shall be placed within the exposure zone so that drops of
solution from the test specimen or any other source are not collected. The collectors shall be
positioned in the proximity of the specimens, one near to a nozzle and the other, as far as
possible from all nozzles. It shall be secured so that, for each 80 cm² of horizontal collecting
area, fog accumulates in each collector at a rate between 1,0 ml to 2,0 ml of solution per
hour, based on an average run of at least 16 h continuous spray.
NOTE Suitable collecting devices are glass funnels with the stems inserted through stoppers into graduated
cylinders or crystallising dishes. Funnels and dishes with a diameter of 100 mm have an area of about 80 cm².
8.4.2.2.4 Salt solution
The salt solution shall consist of 0,05 % sodium chloride (NaCl) and 0,35 % ammonium
sulphate (NH ) (SO ) by mass. The water shall be distilled or de-ionised water. The sodium
4 2 4
chloride shall be substantially free of nickel and copper and shall contain, on the dry basis,
not more than 0,1 % of sodium iodide and not more than 0,3 % of total impurities. The
ammonium sulphate shall contain not more than 0,3 % total impurities. Some salts contain
additives that may act as corrosion inhibitors; careful attention shall be given to the chemical
content of the salt.
The pH of the collected solution shall be between 5,0 and 5,4.
8.4.2.2.5 Air supply
The compressed air supply to the nozzle or nozzles, for atomising the salt solution, shall be
free of oil and dirt and maintain the air supply between 70 kPa and 170 kPa.
8.4.2.2.6 Procedure
The test shall consist of cycles of a 1 h drying period and a 1 h fog period. The electrolyte
shall be a solution of sodium chloride and ammonium sulphate. The fog period shall be
performed at ambient temperature, while the drying-off shall be at higher temperature. The
solution atomising air shall not be saturated with water.
During the fog period, no heating shall be applied to the cabinet. The fog exposure shall be at
(24 ± 3) °C.
During the drying-off period the temperature throughout the exposure zone shall reach and
remain at (35 ± 2) °C within 45 min of switching from the fog period to the dry period. The
drying-off shall be achieved by purging the chamber with fresh air so that within 45 min all
visible moisture shall be dried off the specimen. Humidified air shall not be used for drying.
NOTE As the specimen cycles from wet to dry it is subjected to a range of solution concentration varying from
dilute during the fog period to very concentrated just before the water dries off completely.
8.4.2.2.7 Cleaning
There shall be no cleaning of the test samples between the test cycles.
At completion of the test the samples shall be cleaned in accordance with 8.3.
8.4.3 Immersion tests (optional)
NOTE Two test methods are provided to allow for the different climatic conditions encountered in service.
Method 1 is provided to cater for severe salt pollution e.g. western coast of UK. Method 2 simulates a severely
corrosive atmosphere e.g. near heavy industry.
8.4.3.1 Immersion test (Method 1)
8.4.3.1.1 Principle
For saline polluted areas an optional additional test shall be carried out when this is agreed
between the customer and the supplier. In order to minimise testing, when agreed, this test
shall be carried out during the mandatory heat cycle tests as provided in EN 50483-5.
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8.4.3.1.2 Test arrangement
This shall be, generally, in accordance with EN 50483-5, 5.2 but in particular the test circuit,
as described in EN 50483-5, 5.2.1, shall be modified to allow the samples to be fully
immersed in a saline solution during the heat cycle.
The saline solution shall be maintained at 29,22 g/l (approximately 3 % of mass)
concentration of NaCl throughout the test.
NOTE 1 A practical arrangement is to place the test samples in a tank and pump the saline solution from a
reservoir below. The tank can then be drained back into the reservoir after the required immersion period.
NOTE 2 The test loop may be arranged so that the samples, but not the measurement points, are immersed in the
saline solution. Figure 1 shows a typical arrangement.
Key
1 potential points 3 connector
2 cable core 4 salt water
Figure 1 – Suggested arrangement for connections –
Optional immersion test Method 1
8.4.3.1.3 Procedure
The procedure shall, generally, be in accordance with EN 50483-5, 5.2, 5.3, 5.4 and 5.5.
However, in particular, the subsequent heat cycles defined in EN 50483-5, 5.5.2 shall be
modified to include the immersion of the samples.
and they shall be fully
Immersion of the test samples shall occur on completion of period t
1
immersed for a minimum period of 5 min. The time of immersion shall be considered part of
the cooling period t . Periods, t and t , are shown in EN 50483-5, Figure 3.
2 1 2
8.4.3.1.4 Assessment of results
The assessment, of the samples, shall be carried out in accordance with EN 50483-5, 5.5.4.
8.4.3.1.5 Requirements
The samples shall meet the requirements of EN 50483-5, 5.6.
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EN 50483-6:2009 – 10 –
8.4.3.2 Immersion test (Method 2)
8.4.3.2.1 Principle
This test reproduces the stresses on organic materials due to corrosive environments.
This test shall be carried out within the climatic ageing test (Method 1) of 8.5.1, after the
completion of Period C and before Period D.
8.4.3.2.2 Test arrangement
The samples shall be those tested in Period C of climatic ageing tests.
The acid solution for the test shall contain H SO , HNO and HCl dissolved in distilled water in
2 4 3
order to obtain a pH value equal to 2. The following table reports the quantities of the above
components.
Table 1 – Quantities for acid solution components
a b
Acid Quantity
mg
H SO at 98 % 245
2 4
HNO at 90 % 315
3
HCl at 37 % 50
a
% in mass.
b
Mass per litre of distilled water.
The temperature of the acid solution shall be (45 ± 3) °C.
8.4.3.2.3 Procedure
The acidity of the solution shall be checked before the immersion of the samples.
The tests samples shall be completely immersed in the acid solution for a duration time of
23 h.
The solution shall be changed if the pH is greater than or equal to 2,5.
8.4.3.2.4 Requirements
This test has no specific requirements as it forms a part of climatic test Method 1, 8.5.1.
8.5 Climatic ageing test
Method 1 or Method 2 shall be used.
NOTE Two methods of testing are provided to meet the requirements of the climatic ageing test and provide for
the use of available test equipment. The first, Method 1, is based on the test procedure, which has been used in
some countries, for a number of years, and experience has been gained of both the procedures and outcomes of
the test. This is based on a test method included in HD 626. The second, Method 2 has also been used in some
countries with similarly successful experience and is provided as an alternative. It is based on EN 60068-2-5.
8.5.1 Method 1
8.5.1.1 Principle
The test subjects samples to a combined cycle of climatic constraints: ultraviolet radiation,
humidity, water spray and temperature extremes.
Test conditions have been derived with the aim of reproducing normal service conditions.
This test shall be carried out in a single chamber or in separated chambers only for the
climatic constraints at low temperature.
The test conditions and test equipment detailed in 8.5.1.2 and 8.5.1.3 are interdependent. Any
modification of parameters could affect the consistency of the test results.
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NOTE Other arrangements that provide ultraviolet radiation, humidity, rain and temperature extremes that use
developed testing technology may be agreed between customer and supplier.
8.5.1.2 Test equipment
NOTE Annex D (informative) provides a typical test equipment specification.
8.5.1.2.1 Source of light beam
The light source shall produce a spectrum that is as close as possible to the solar spectrum at
ground level. This spectrum shall be consistent throughout the test and the energy absorbed,
by the samples, shall be determined with a black standard thermometer, which shall measure
the temperature rise created by the light source.
Temperature values shall be maintained between the values given in 8.5.1.3.4 by natural
ventilation of the chamber.
Control and measurement shall be in accordance with 8.5.1.3.
8.5.1.2.2 Test chamber
The test chamber (see informative Figure D.1) shall contain a rotating sample rack. A system
of ventilation shall produce air circulation around the samples in order to reduce the rise of
surface temperature.
The distance between the samples and lamp shall be adapted to the power of this lamp. The
arrangement shall be such so that the energy of lighting received by the samples does not
vary by more than ± 15 % from the mean value E defined in 8.5.1.3.1.
m
To ensure consistent and equal exposure of the samples the rack shall be rotated around the
lamp. The speed of rotation of the rack shall be between 1 turn/min and 5 turns/min. The
orientation of the samples shall be such that the same face is maintained towards the light
source throughout the rotation of the rack.
8.5.1.2.3 Black standard thermometer
A black standard thermometer shall be used to measure the temperature within the chamber.
It shall be placed at the same distance from the lamp as the samples under test. Its
orientation shall be such that the centre of the plate is vertically aligned with the centre of the
lamp. The darkened metallic surface of the thermometer shall face the lamp.
8.5.1.2.4 Sprinkler device
Sprinkling shall be carried out by one or several rain injectors, allowing the spraying of the
front face of every sample with approximately 50° angle of rain, the outflow of each sprinkler
unit shall be between 15 l/h and 25 l/h. The sprinklers shall be assembled vertically above
each other and shall be fed with water whose resistivity shall be greater than or equal to
0,1 MΩ.cm (conductivity less than or equal to 0,001 S/m). The period of spraying shall be for
3 min and the interval between spraying (dry period) shall be 17 min.
NOTE 1 The temperature of the spray water should be between 10 °C and 30 °C.
NOTE 2 The arrangement is shown in informative Figure D.1. The sprinkling system may incorporate recycling of
the spray water. However if this method is employed it should ensure that the water does not become contaminated
before it is reused for spraying.
8.5.1.3 Controls and measurements of the test parameters
8.5.1.3.1 Light beam source
The light beam shall be produced by a cylindrical lamp with a xenon arc and shall be modified
by associated filters. The filters shall eliminate wavelengths lower than 270 nm, in order to
provide, at ground level, a spectrum close to that of the solar spectrum, (typically with
wavelengths above 290 nm). (Normally, there are two filters, one inner quartz filter and an
outer borosilicate filter).
The characteristics of the optical filters will change with use, both because of ageing and
accretion of deposits. In order to maintain the necessary luminous characteristics they shall
be cleaned or replaced at convenient intervals.
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The xenon lamps also undergo ageing which produces a reduction of the energy intensity in
the ultraviolet domain. To minimise the effects of this ageing, it is necessary to increase the
current supplying the lamp in order to maintain the energy flow, emitted in a band of the
ultraviolet spectrum from 300 nm to 400 nm, at a
...