IS 335 : 2018 New Insulating Oils — Specification
1. Scope
This standard covers specifications and test methods for unused mineral insulating oils. It applies to oil delivered to the agreed point and time of delivery, intended for use in transformers, switchgear and similar electrical equipment in which oil is required as an insulant and for heat transfer. These oils are obtained by distillation and refining of crude petroleum.
Oils with and without additives are both within the scope of this standard.
This standard is applicable only to unused mineral insulating oils.
Reclaimed oils are beyond the scope of this standard.
This standard does not apply to mineral oils used as impregnants in cables or capacitors.
NOTE - Mineral insulating oils complying with the requirements of this standard, of the same class and containing no additives ( see 3.4), are considered to be compatible with one another and can be mixed in any proportion. This does not apply to oils containing additives. Where the user wishes to mix such oils, a check is recommended to be made to ensure that the mixture meets the requirements of this standard.
2. References
The standards listed in Annex A contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards listed in Annex A.