IEC 62701:2014

IEC 62701 ®
Edition 1.0 2014-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fluids for electrotechnical applications – Recycled mineral insulating oils for
transformers and switchgear
Fluides pour applications électrotechniques – Huiles minérales isolantes
recyclées pour transformateurs et appareillages de connexion

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IEC 62701 ®
Edition 1.0 2014-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fluids for electrotechnical applications – Recycled mineral insulating oils for

transformers and switchgear
Fluides pour applications électrotechniques – Huiles minérales isolantes

recyclées pour transformateurs et appareillages de connexion

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX N
ICS 29.040 ISBN 978-2-8322-1121-2

– 2 – IEC 62701:2014  IEC 2014

CONTENTS
FOREWORD . 3

INTRODUCTION . 5

1 Scope . 6

2 Normative references . 6

3 Terms and definitions . 8

4 Properties of oil – Refining and stability . 9

5 Classification, identification, general delivery requirements . 9
5.1 Classification . 9
5.2 Requirements . 9
5.3 Miscibility . 9
5.4 Identification and general delivery requirements . 9
6 Properties, their significance and test methods . 9
6.1 Water content . 9
6.2 Acidity . 10
6.3 Antioxidant additives . 10
6.4 Gassing tendency . 10
6.5 Polycyclic aromatics content (PCAs) . 10
6.6 Polychlorinated biphenyl content (PCBs) . 10
6.7 2-Furfural (2-FAL) and related compounds content . 11
6.8 Particle content . 11
6.9 DBDS content. 11
6.10 Stray gassing of oil . 11
Bibliography . 14

Table 1 – General specifications . 12

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
FLUIDS FOR ELECTROTECHNICAL APPLICATIONS –

RECYCLED MINERAL INSULATING OILS

FOR TRANSFORMERS AND SWITCHGEAR

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62701 has been prepared by IEC technical committee 10: Fluids

for electro technical applications.
This International Standard is in line with IEC 60296 and IEC 60422.
The text of this standard is based on the following documents:
FDIS Report on voting
10/908/FDIS 10/910/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 – IEC 62701:2014  IEC 2014

The committee has decided that the contents of this publication will remain unchanged until

the stability 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.
INTRODUCTION
Health and safety
This International Standard does not purport to address all the safety problems associated

with its use. It is the responsibility of the user of the standard to establish appropriate health

and safety practices and determine the applicability of regulatory limitations prior to use.

The mineral insulating oils which are the subject of this standard should be handled with due

regard to personal hygiene. Direct contact with the eyes may cause irritation. In the case of

eye contact, irrigation with copious quantities of clean running water should be carried out

and medical advice sought. Some of the tests specified in this standard involve the use of
processes that could lead to a hazardous situation. Attention is drawn to the relevant standard
for guidance.
Environment
This standard is applicable rise to mineral insulating oils, chemicals and used sample
containers. The disposal of these items shall be carried out according to the local regulations
with regard to the impact on the environment. Every precaution should be taken to prevent
release of mineral insulating oil into the environment.

– 6 – IEC 62701:2014  IEC 2014

FLUIDS FOR ELECTROTECHNICAL APPLICATIONS –

RECYCLED MINERAL INSULATING OILS

FOR TRANSFORMERS AND SWITCHGEAR

1 Scope
This International Standard specifies requirements for recycled mineral insulating oils

intended for use in transformers, switchgear, and similar electrical equipment in which oil is
required for insulation and heat transfer.
These oils are produced by processes employed offsite.
Oils treated and reconditioned on-site are not within the scope of this standard.
Oils with and without additives are within the scope of this standard.
Such oils will have originally been supplied in compliance with a recognized unused mineral
insulating oil specification.
This standard does not differentiate between the methods used to recycle mineral insulating
oil.
This standard does not apply to mineral insulating oils used as impregnates in cables or
capacitors.
For the purpose of this standard the following subclauses of IEC 60296:2012 apply:
– 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9;
– 4.1, 4.3, 4.4;
– 5.1, 5.5;
– 6.1, 6.2, 6.4, 6.5, 6.6, 6.8, 6.9, 6.10, 6.11.1, 6.11.3, 6.11.4, 6.12, 6.14, 6.15, 6.16;
– 7.1.
NOTE Some types of re-refined oils are equivalent to unused oils in terms of performance, in which case IEC
60296 is applicable. This should be stated by the manufacturer.

2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60156, Insulating liquids – Determination of the breakdown voltage at power frequency –
Test method
IEC 60247, Insulating liquids – Measurement of relative permittivity, dielectric dissipation
factor (tan δ) and d.c. resistivity
IEC 60296:2012, Fluids for electrotechnical applications – Unused mineral insulating oils for
transformers and switchgear
IEC 60422, Mineral insulating oils in electrical equipment – Supervision and maintenance

guidance
IEC 60628, Gassing of insulating liquids under electrical stress and ionization

IEC 60666, Detection and determination of specified additives in mineral insulating oils

IEC 60814, Insulating liquids – Oil-impregnated paper and pressboard – Determination of

water by automatic coulometric Karl Fischer titration

IEC 60970, Insulating liquids – Method for counting and sizing particles

IEC 61125:1992, Unused hydrocarbon based insulating liquids – Test methods for evaluating
the oxidation stability
Amendment 1 (2004)
IEC 61198, Mineral insulating oils – Methods for the determination of 2-furfural and related
compounds
IEC 61619, Insulating liquids – Contamination by polychlorinated biphenyls (PCBs) – Method
of determination by capillary column gas chromatography
IEC 61620, Insulating liquids – Determination of the dielectric dissipation factor by
measurement of the conductance and capacitance – Test method
IEC 61868, Mineral insulating oils – Determination of kinematic viscosity at very low
temperatures
IEC 62021-1, Insulating liquids – Determination of acidity – Part 1: Automatic potentiometric
titration
IEC 62021-2, Insulating liquids – Determination of acidity – Part 2: Colorimetric titration
IEC 62535, Insulating liquids – Test method for detection of potentially corrosive sulphur in
used and unused insulating oils
IEC 62697-1, Test methods for quantitative determination of corrosive sulfur compounds in
unused and used insulating liquids – Part 1: Test method for quantitative determination of
dibenzyldisulfide (DBDS)
ISO 2719, Determination of flash point – Pensky-Martens closed cup method
ISO 3016, Petroleum products – Determination of pour point
ISO 3104, Petroleum products – Transparent and opaque liquids – Determination of kinematic
viscosity and calculation of dynamic viscosity
ISO 3675, Crude petroleum and liquid petroleum products – Laboratory determination of
density – Hydrometer method
ISO 12185, Crude petroleum and petroleum products – Determination of density – Oscillating
U-tube method
ISO 14596, Petroleum products – Determination of sulfur content – Wavelength-dispersive X-
ray fluorescence spectrometry
– 8 – IEC 62701:2014  IEC 2014

ASTM D971, Standard Test Method for Interfacial Tension of Oil Against Water by the Ring

Method
DIN 51353, Testing of insulating oils; detection of corrosive sulfur; silver strip test

EN 14210, Surface active agents – Determination of interfacial tension of solutions of surface

active agents by the stirrup or ring method

IP 346, Determination of polycyclic aromatics in unused lubricating base oils and asphaltene

free petroleum fractions – Dimethylsulfoxide extraction refractive index method

IP 373, Petroleum products – Determination of sulphur content – Oxidative microcoulometry
method
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60296, as well as
the following apply.
3.1
recycled mineral insulating oil
general term to encompass mineral insulating oils previously used in electrical equipment that
has been subjected to re-refining or reclaiming(regeneration) off-site
Note 1 to entry: The characteristics of recycled oil are heavily dependent on the crude from which it was refined,
the original refining technique, the service history and the type of recycling process. Natural antioxidants originally
present in the oil might have been depleted in service or removed by the recycling process.
Note 2 to entry: Recycled oil is not appropriate for use in some applications.
Note 3 to entry: Such recycled oils are often produced from mixtures of mineral insulating oils of different origins.
Note 4 to entry: A blend of unused and recycled oils in any proportion is regarded as being recycled oil.
Note 5 to entry: Due to local legislation, in some countries, it is advisable to categorize used electrical oil as
waste oil and complete separation of handling of unused and used oils is required
3.2
Reclaimed(regenerated) mineral insulating oil
mineral insulating oil used in electrical equipment, which has been subjected to chemical and
physical processing to eliminate soluble and insoluble contaminants
Note 1 to entry: Where these processes are performed on oil contained in equipment in service, so called “on-site

reclamation”, such treated oils are beyond the scope of this standard.
3.3
reconditioned mineral insulating oil
mineral insulating oil used in electrical equipment, which has been subjected to a physical
process to remove insoluble contaminants and free water and to reduce the levels of
dissolved moisture and gases
3.4
re-refined mineral insulating oil
mineral insulating oil used in electrical equipment that has been removed from service and
subjected to a process similar to that used for the production of unused mineral insulating oil
from virgin feedstock, including distillation and hydrogenation, in order to reduce the level of
unwanted compounds
Note 1 to entry: Such re-refined oils are often produced from mixtures of mineral insulating oils of different
origins.
4 Properties of oil – Refining and stability

Properties of oil are influenced by quality and type of the original oil refining, used oil

recycling and additives.
NOTE These properties can include appearance, interfacial tension, sulphur content, acidity, corrosive sulphur,

2-furfural and related compounds content and stray gassing.

5 Classification, identification, general delivery requirements

5.1 Classification
For the purposes of this standard, recycled mineral insulating oils are classified as in 5.1 of
IEC 60296:2012.
5.2 Requirements
The general requirements of this standard are given in Table 1.
5.3 Miscibility
Recycled mineral insulating oils of the same class (see 5.1.1 of IEC 60296:2012), the same
group (see 5.1.2 of IEC 60296:2012), the same LCSET (see 5.1.3 of IEC 60296:2012) and
containing the same types of additives are considered to be miscible and compatible with
each other (see also IEC 60422).
5.4 Identification and general delivery requirements
The following applies:
a) Oil is normally delivered in bulk, rail tank cars, tank containers or packed in drums or IBC
(intermediate bulk containers). These shall be clean and suitable for this purpose to avoid
any contamination.
b) Oil drums and IBC containers shall carry at least the following markings:
– supplier's designation;
– classification (see 5.1 of IEC 60296:2012);
– oil quantity;
– recycled oil compliant with IEC 62701.
c) As agreed between the supplier and purchaser, each oil delivery shall be accompanied by
a document specifying the supplier’s designation, oil classification, compliance certificate

and process of recycling.
d) The supplier shall declare the generic type of all additives, and their concentrations in the
cases of inhibitors and passivators.
NOTE This document is intended to be traceable to a specific batch of oil produced.
6 Properties, their significance and test methods
6.1 Water content
A low water content of mineral insulating oil is necessary to achieve adequate breakdown
voltage and low dissipation losses. To avoid separation of free water, recycled mineral
insulating oil shall have limited water content. Before filling the electrical equipment, the oil
should be treated to meet the requirements of IEC 60422. Water content shall be measured in
accordance with IEC 60814.
– 10 – IEC 62701:2014  IEC 2014

6.2 Acidity
Recycled mineral insulating oil should have been treated to remove acidity and oxidation by-

products. Acidity shall be measured according to IEC 62021-1 or IEC 62021-2.

6.3 Antioxidant additives
Antioxidants (see 3.5 of IEC 60296:2012) slow down the oxidation of oil and therefore the
formation of degradation products such as oil sludge and acidity. It is necessary to know the

concentration of antioxidants for the correct classification of the oil. Additionally, the actual

concentration is required to monitor ageing of the oil.

Additives that slow down the oxidation of mineral insulating oils include:
– inhibitors such as phenols and amines (see 3.5.1 of IEC 60296:2012). The most widely
used inhibitors are di-tert-butyl-para-cresol (DBPC) and di-tert-butyl-phenol (DBP).
Detection and measurement of DBPC and DBP shall be carried out in accordance with
IEC 60666. IEC test methods are not available for other types of inhibitors;
– other antioxidant additives such as sulphur- and phosphor-containing compounds, e.g.
organic polysulphides and dithiophosphates (see 3.5.2 of IEC 60296:2012). An antioxidant
additive of this type is dibenzyl disulphide (DBDS) (see 6.10 of IEC 60296:2012), but it is
not accepted in recycled oils as it is known to be corrosive to copper and will likely result
in the oil failing the potentially corrosive sulphur test IEC 62535. The IEC 62697-1 test
method was prepared only for DBDS (see 6.9 below) and not for the other antioxidant
additives of this type;
– metal passivators (see 3.5.3 and 6.11.3 of IEC 60296:2012).
6.4 Gassing tendency
Gassing tendency of mineral insulating oil, i.e. the gas absorbing property of oil when
subjected to corona partial discharges, is only necessary and important for special equipment
like HV (high voltage) instrument transformers and bushings. It is a measure of the rate of
absorption or evolution of gas into oil under prescribed laboratory conditions. Gas absorption
properties could be related to oil aromatic content. Gassing tendency shall be measured using
method A of IEC 60628.
NOTE Additives such as 1,2,3,4 tetrahydronaphtalene (tetralin), mono or dibenzyltoluene and others have been
proposed to reduce the gassing tendency of some oils, but are not described in IEC 60666. Mono and
dibenzyltoluene are described in IEC 60867 [1] .
6.5 Polycyclic aromatics content (PCAs)
Some PCAs are classified to be carcinogens and therefore need to be controlled to an
acceptable level in mineral insulating oil. The total amount of PCAs can be measured by

extraction with DMSO (dimethylsulfoxide) under the conditions of IP 346.
NOTE 1 Acceptable limits of total or individual PCAs are specified in national and local regulations.
NOTE 2 Values and limits as given in IP 346 are substantiated for virgin base oils only.
6.6 Polychlorinated biphenyl content (PCBs)
Recycled mineral insulating oil shall be free from PCBs. The reference test method shall be
IEC 61619.
NOTE Acceptable limits of total or individual PCBs are specified in national and local regulations. Further
European specifications are described in Directive CE/59/96 [2].
—————————
References in square brackets refer to the Bibliography.

6.7 2-Furfural (2-FAL) and related compounds content

2-FAL and related compounds in recycled mineral insulating oils can result from improper

redistillation after solvent extraction, from cellulose degradation within equipment that

previously contained the oil or from contamination with used oil.

Recycled mineral insulating oils should have a low level of 2-FAL and related compounds;

measurement shall be carried out according to IEC 61198.

NOTE 1 The “related compounds” are: 5-hydroxymethyl-2-furfural (5HMF), 2-furfurylalcohol (2FOL), 2-acetylfuran

(2ACF) and 5-methyl-2-furfural (5MEF).

NOTE 2 Not all recycling processes will be able to eliminate all furanic compounds and some trace may remain.
6.8 Particle content
Particles in recycled mineral insulating oil might result from manufacturing, storage or
handling of the oil, and can affect its breakdown voltage (see 6.4 of IEC 60296:2012).
Measurement shall be carried out according to IEC 60970.
6.9 DBDS content
This compound may become corrosive at normal transformer operating temperatures and can
produce copper sulphide. It therefore should not be present in recycled mineral insulating oils
(see 6.3 of this standard). Measurement shall be carried out according to IEC 62697-1.
6.10 Stray gassing of oil
Some oils can produce gases such as hydrogen, light hydrocarbons and carbon oxides at low
temperatures (<120 °C) without thermal stress or electrical faults in a transformer. This
phenomenon could result in a high production of gases and a misinterpretation of dissolved
gas analysis (DGA) results.
NOTE Methods to measure stray gassing are described in CIGRE Brochure 378 [3] and ASTM D7150 [4].
Inhibited grades typically produce less stray gassing than uninhibited ones.

– 12 – IEC 62701:2014  IEC 2014

Table 1 – General specifications

Limits
Property Test method
Low temperature
Transformer oil
switchgear oil
1 Function
2 2
Viscosity at 40 °C ISO 3104 Max. 12 mm /s Max. 3,5 mm /s

a 2
Viscosity at –30 °C ISO 3104 Max. 1 800 mm /s --

b 2
Viscosity at –40 °C IEC 61868 -- Max. 400 mm /s

Pour point ISO 3016 Max. –40 °C Max. –60 °C

c d
Water content IEC 60814 Max. 30 mg/kg / 40 mg/kg

e
Breakdown voltage IEC 60156 Min. 30 kV / 70 kV
Density at 20 °C ISO 3675 or ISO 12185 Max. 0,895 g/ml
Dielectric dissipation factor IEC 60247 or IEC 61620 Max. 0,005
(DDF) at 90 °C
Particle content IEC 60970 No general requirement
2 Refining/stability
Appearance -- Clear, free from sediment and suspended matter
Acidity IEC 62021-1 or 62021-2 Max. 0,01 mg KOH/g
f
Interfacial tension EN 14210 or ASTM D971 No general requirement
Total sulphur content IP 373 or ISO 14596 No general requirement
Corrosive sulphur DIN 51353 Not corrosive
Potentially corrosive IEC 62535 Not corrosive
sulphur
DBDS IEC 62697-1 Not detectable (<5 mg/kg)
Inhibitors of IEC 60666 IEC 60666 (U) uninhibited oil: not detectable (<0,01 %)
(T) trace inhibited oil: < 0,08 %
(I) inhibited oils: 0,08 % – 0,40 %
(see 3.6 to 3.8 of IEC 60296:2012)
IEC 60666
Metal passivator additives Not detectable (<5 mg/kg) or as agreed upon with
of IEC 60666
the purchaser
g
Other additives  See
2-Furfural and related IEC 61198
Not detectable (<0,05 mg/kg) for each individual
compounds content
compound
h
Stray gassing See 6.10 No general requirement
3 Performance
Oxidation stability IEC 61125, Method C
For oils with other antioxidant additives and metal
passivator additives, see 6.12 of IEC 60296:2012
Test duration
(U) Uninhibited oil: 164 h
(T) Trace inhibited oil: 332 h

(I) Inhibited oil: 500 h
i
- Total acidity 1.9.4 of IEC 61125:1992 Max. 1,2 mg KOH/g
i
- Sludge 1.9.1 of IEC 61125:1992 Max. 0,8 %
I, j
- DDF at 90 °C IEC 60247 and Amendment Max. 0,500
1:2004 of IEC 61125
h
Gassing tendency IEC 60628, Method A No general requirement
4 Health, safety and environment (HSE)
Flash point ISO 2719 Min. 135 °C Min. 100 °C
PCA content IP 346 Max. 3 %
PCB content IEC 61619
Not detectable (<2 mg/kg)
NOTE 1 Particle content in drums at delivery of oil is agreed between supplier and customer, based on a

statistical reference at delivery.

NOTE 2 In Canada and USA, where requirements for oxidation resistance are lower for some applications, test
durations can be reduced to: (T) trace inhibited oil: 164 h; (I) inhibited oil: 332 h. These requirements are of a

permanent nature.
NOTE 3 Alternative values can be agreed upon between users and suppliers for maintenance purposes as
follows:
Acidity: IEC 62021-1 or IEC 62021-2: <0,02 mg KOH/g;
PCB: IEC 61619: <5 mg/kg;
2-Furfural and related compounds content: IEC 61198: <0,1mg/kg for each individual compound.

a
This is the standard lowest cold start energizing temperature (LCSET) for a transformer oil (see 6.1 of
IEC 60296:2012) and can be modified depending on the climatic condition of each country. Pour point should
be minimum 10 K below LCSET.
b
Standard LCSET for low temperature switchgear oil.
c
For bulk supply.
d
For delivery in drums and IBC.
e
After laboratory treatment (see 6.4 of IEC 60296:2012).
f
Where it is used as a general requirement, a limit of minimum 40 mN/m is recommended.
g The supplier shall declare the generic type of all additives, and their concentrations in the case of antioxidant
additives.
h To be agreed upon between supplier and purchaser.
i At the end of oxidation stability tests.
j A DDF of max. 0,020 after 2 h of oxidation (see IEC 61125, Method C) is recommended for application in EHV
instrument transformers and bushings.

– 14 – IEC 62701:2014  IEC 2014

Bibliography
[1] IEC 60867, Insulating liquids – Specifications for unused liquids based on synthetic

aromatic hydrocarbons
[2] Council Directive 96/59/EC, Disposal of polychlorinated biphenyls and polychlorinated

terphenyls (PCB/PCT), 16 September 1996

[3] CIGRE Technical Brochure 378, Copper sulphide in transformer insulation, 2009

[4] ASTM D7150, Standard Test Method for the Determination of Gassing Characteristics of
Insulating Liquids Under Thermal Stress at Low temperature
Additional non cited references
CIGRE Technical Brochure 413, Insulating oil reclamation and dechlorination, 2010

_____________
– 16 – IEC 62701:2014  IEC 2014

SOMMAIRE
AVANT-PROPOS . 17

INTRODUCTION . 17

1 Domaine d'application . 20

2 Références normatives . 20

3 Termes et définitions . 22

4 Propriétés de l'huile – Raffinage et stabilité . 23

5 Classification, identification, exigences générales de livraison . 23
5.1 Classification . 23
5.2 Exigences . 23
5.3 Miscibilité . 23
5.4 Exigences générales et d'identification à la livraison . 23
6 Propriétés, leur signification et méthodes d’essai . 24
6.1 Teneur en eau . 24
6.2 Acidité . 24
6.3 Additifs antioxydants . 24
6.4 Tendance au gassing . 24
6.5 Teneur en hydrocarbures aromatiques polycycliques (HAP) . 25
6.6 Teneur en polychlorobiphényles (PCB) . 25
6.7 Teneur en 2-Furfural (2-FAL) et ses dérivés . 25
6.8 Teneur en particules . 25
6.9 Teneur en DBDS . 25
6.10 Stray gassing de l'huile . 25
Bibliographie . 28

Tableau 1 – Spécifications générales . 26

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE

____________
FLUIDES POUR APPLICATIONS ÉLECTROTECHNIQUES –

HUILES MINÉRALES ISOLANTES RECYCLÉES POUR

TRANSFORMATEURS ET APPAREILLAGES DE CONNEXION

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (CEI) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a
pour objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les
domaines de l'électricité et de l'électronique. A cet effet, la CEI – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
public (PAS) et des Guides (ci-après dénommés "Publication(s) de la CEI"). Leur élaboration est confiée à des
comités d'études, aux travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les
organisations internationales, gouvernementales et non gouvernementales, en liaison avec la CEI, participent
également aux travaux. La CEI collabore étroitement avec l'Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de la CEI concernant les questions techniques représentent, dans la mesure
du possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de la CEI
intéressés sont représentés dans chaque comité d’études.
3) Les Publications de la CEI se présentent sous la forme de recommandations internationales et sont agréées
comme telles par les Comités nationaux de la CEI. Tous les efforts raisonnables sont entrepris afin que la CEI
s'assure de l'exactitude du contenu technique de ses publications; la CEI ne peut pas être tenue responsable
de l'éventuelle mauvaise utilisation ou interprétation qui en est faite par un quelconque utilisateur final.
4) Dans le but d'encourager l'uniformité internationale, les Comités nationaux de la CEI s'engagent, dans toute la
mesure possible, à appliquer de façon transparente les Publications de la CEI dans leurs publications
nationales et régionales. Toutes divergences entre toutes Publications de la CEI et toutes publications
nationales ou régionales correspondantes doivent être indiquées en termes clairs dans ces dernières.
5) La CEI elle-même ne fournit aucune attestation de conformité. Des organismes de certification indépendants
fournissent des services d'évaluation de conformité et, dans certains secteurs, accèdent aux marques de
conformité de la CEI. La CEI n'est responsable d'aucun des services effectués par les organismes de
certification indépendants.
6) Tous les utilisateurs doivent s'assurer qu'ils sont en possession de la dernière édition de cette publication.
7) Aucune responsabilité ne doit être imputée à la CEI, à ses administrateurs, employés, auxiliaires ou
mandataires, y compris ses experts particuliers et les membres de ses comités d'études et des Comités
nationaux de la CEI, pour tout préjudice causé en cas de dommages corporels et matériels, ou de tout autre
dommage de quelque nature que ce soit, directe ou indirecte, ou pour supporter les coûts (y compris les frais
de justice) et les dépenses découlant de la publication ou de l'utilisation de cette Publication de la CEI ou de
toute autre Publication de la CEI, ou au crédit qui lui est accordé.
8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L’attention est attirée sur le fait que certains des éléments de la présente Publication de la CEI peuvent faire
l’objet de droits de brevet. La CEI ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits

de brevets et de ne pas avoir signalé leur existence.
La Norme internationale CEI 62701 a été établie par le comité d'études 10 de la CEI: Fluides
pour applications électrotechniques.
La présente Norme internationale est conforme à la CEI 60296 et à la CEI 60422.
Le texte de cette norme est issu des documents suivants:
FDIS Rapport de vote
10/908/FDIS 10/910/RVD
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à l'approbation de cette norme.
Cette publication a été rédigée selon les Directives ISO/CEI, Partie 2.

– 18 – IEC 62701:2014  IEC 2014

Le comité a décidé que le contenu de cette publication ne sera pas modifié avant la date de

stabilité indiquée sur le site web de la CEI sous "http://webstore.iec.ch" dans les données

relatives à la publication recherchée. A cette date, la publication sera

• reconduite,
• supprimée,
• remplacée par une édition révisée, ou

• amendée.
INTRODUCTION
Santé et sécurité
La présente Norme internationale ne vise pas à répondre à tous les problèmes de sécurité

liés à son utilisation. Il est de la responsabilité de l'utilisateur de cette norme de mettre en

place les pratiques sanitaires et de sécurité adéquates, et de déterminer avant utilisation si

des contraintes réglementaires s'appliquent.

Il convient que les huiles minérales isolantes dont traite cette norme soient manipulées en

respectant l'hygiène personnelle. Le contact direct avec les yeux peut provoquer une

irritation. En cas de contact oculaire, il est recommandé de laver abondamment à l'eau
courante propre, et de demander un avis médical. Certains des essais spécifiés dans cette
norme impliquent des opérations pouvant conduire à une situation dangereuse. Les lignes
directri
...