Oil approval

Oil for use in transformers, switches and similar electrical equipment in which insulating oil is required must comply with a set of characteristics. These properties depend on the type of oil. For new mineral oil, the standard UNE EN 60296 applies. For new natural esters, the standard UNE-EN 62770 applies. For synthetic esters, the standard UNE-EN 61099 applies, and for silicone, the standard UNE-EN 60836 applies.

Tests and regulations:

Dissolved furanic compounds: UNE EN 61198:1996
Visual appearance and colour: ISO 2049:1996
Water content by coulometric Karl-Fischer titration assessment: UNE-EN 60814:99
Determination of dielectric rupture tension: UNE-EN 60156:97
Determination of the Dielectric Loss Factor (Tg δ): UNE-EN 60247:04
Determination of Neutralisation Index: PE ACE 04 Rev 06
Methods for counting and sizing particles. : UNE-EN 60970:2008
Neutralisation index, colourimetric acidity method: IEC 62021-2:2007
Determination of acidity. Test methods for non-mineral insulating oils: UNE-EN 62021-3:2015
Infrared spectrometry. : PT-QUI-27 REV01
Analysis of polychlorinated biphenyls (PCBs): UNE-EN 61619:04
Compatibility of insulating mineral oils: UNE EN 60422:2013
Corrosive sulphur compounds in new and used insulating liquids (DBDS): UNE EN 62697-1:2013
Detection of potentially corrosive sulphur: UNE-EN 62535:2009
Detection of corrosive sulphur: DIN 51353
Determination of specified additives content: UNE EN 60666:2011
Precipitable sediment and sludge: UNE EN 60422:2013
Determination of kinematic viscosity at 40ºC: UNE EN ISO 3104:1996
Determination of kinetic viscosity at -30ºC: UNE EN ISO 3104:1996
Viscosity index: ISO 2909:2002
Density: UNE EN ISO 3675:1999
Freezing point: ISO 3016:1994
Flashpoint. Pensky-Martens closed cup method: UNE EN ISO 2719:2003
Detection of specific oxidation inhibitor additives: UNE EN 60666:2011
Interfacial tension of solutions of surface agents. Stirrup or ring method: UNE EN 14210:2004
Oxidation stability of non-inhibited oils (Type U): UNE EN 61125:1996
Oxidation stability of inhibited oils (Type I): UNE EN 61125:1996
Oxidation stability of esters: UNE EN 61125:1997
Determination of the aromatic hydrocarbon content of new mineral insulating oils. IEC 60590: 1977
Determination of the carbon type percentage: Internal procedure
Determination of metals in dielectric oils: ASTM D5185-05
Stray Gassing: ASTM D7150-13
Stray Gassing: UNE 60296:2020
Electrical permittivity: UNE EN 60247:2004
ISO Cleaning Code: ISO 4406:1999
Continuous current resistivity: UNE EN 60247:2004 + ERRATUM: 2005