Covers specifications and test methods for unused silicone liquid intended for use in transformers and other electrotechnical equipment. The specified characteristics of silicone transformer liquid Type 1 are described in Table 1. Other specifications will be added when required.

NOTE Maintenance of used silicone liquid in electrotechnical equipment is covered in a separate publication IEC 60944.

This edition includes the following major technical changes with regard to the first edition:

a) the title has been modified;

b) the scope has been adapted to meet the changes in the title;

c) health, safety and environmental requirements have been revised in order to follow the environmental practice carried out for other insulating liquids. Isopropyl alcohol now replaces chlorinated dissolvents for cleaning test equipment;

d) Clause 8 replaces Section 2 of the first edition. In line with other TC10 documents, ISO 2592 is now the only method specified for measuring fire point and IEC 60814 for water content. Breakdown voltage measurement has now been transferred to IEC 60156;

e) Table 1 replaces Sheet 1 of the first edition. Two technical changes have been made: - the minimum fire point is increased from 330 C to 340 C (in conformity with ASTM D4652) and recognizes also that the test values registered for production are even higher. - neutralization values have been reduced from 0,02 to 0,01 mg KOH/g, in line with production test data.

f) Annex A has been deleted.