IEC 62770:2013

IEC 62770 ®
Edition 1.0 2013-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fluids for electrotechnical applications – Unused natural esters for transformers
and similar electrical equipment

Fluides pour applications électrotechniques – Esters naturels neufs pour
transformateurs et matériels électriques analogues

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IEC 62770 ®
Edition 1.0 2013-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fluids for electrotechnical applications – Unused natural esters for transformers

and similar electrical equipment

Fluides pour applications électrotechniques – Esters naturels neufs pour

transformateurs et matériels électriques analogues

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX Q
ICS 29.040 ISBN 978-2-8322-1191-5

– 2 – 62770  IEC:2013
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 9
4 Properties, their significance and test methods . 9
4.1 General . 9
4.2 Physical properties . 9
4.2.1 Appearance . 9
4.2.2 Viscosity . 10
4.2.3 Pour point . 10
4.2.4 Water content . 10
4.2.5 Density . 10
4.3 Electrical properties . 10
4.3.1 Breakdown voltage . 10
4.3.2 Dielectric dissipation factor (DDF) . 10
4.3.3 Relative permittivity (dielectric constant) . 11
4.4 Chemical properties . 11
4.4.1 Acidity . 11
4.4.2 Corrosive sulfur . 11
4.4.3 Additive content . 11
4.4.4 Furfural content . 11
4.5 Performance . 11
4.5.1 Oxidation stability . 11
4.5.2 Total acidity . 12
4.5.3 Viscosity . 12
4.5.4 Dielectric dissipation factor (DDF) . 12
4.6 Health, safety and environmental (HSE) properties . 12
4.6.1 Fire point and flash point . 12
4.6.2 Polychlorinated biphenyls (PCBs) . 12
4.6.3 Biodegradation . 12
4.6.4 Toxicity . 12
5 Classification, identification, general delivery requirements and sampling . 12
5.1 Classification . 12
5.2 Identification and general delivery requirements . 13
5.3 Sampling . 13
Annex A (normative) Summary of the test method for evaluating oxidation stability of
unused natural esters . 15
A.1 Introductory remark . 15
A.2 Test conditions . 15
A.3 Precision . 15
A.4 Relative repeatability (r) . 15
A.5 Relative reproducibility (R) . 15
Annex B (informative) Specifications of low-viscosity insulating fluids derived from
natural esters . 16
Bibliography . 17

62770  IEC:2013 – 3 –
Table 1 – General specifications . 14
Table A.1 – Relative repeatability and relative reproducibility obtained for different
parameters during RRT . 15
Table B.1 – Specifications for low-viscosity of monoesters derived from natural esters . 16

– 4 – 62770  IEC:2013
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FLUIDS FOR ELECTROTECHNICAL APPLICATIONS –
UNUSED NATURAL ESTERS FOR TRANSFORMERS
AND SIMILAR ELECTRICAL EQUIPMENT

FOREWORD
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