IEC 60836-2005 pdf – Specifications for unused silicone insulating liquids for electrotechnical purposes.
1 Scope This International Standard 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. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 601 56, 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 60475, Method of sampling liquid dielectrics IEC 60628, Gassing of insulating liquids under electrical stress and ionization IEC 6081 4, Insulating liquids – Oil-impregnated paper and pressboard – Determination of water by automatic coulometric Karl Fischer titration IEC 60944, Guide for the maintenance of silicone transformer liquids ISO 221 1 , Liquid chemical products – Measurement of colour in Hazen units (platinum-cobalt scale) ISO 2592, Determination of flash and fire points – Cleveland open cup method ISO 271 9, Determination of of flash point – Pensky Martens closed cup method ISO 301 6, Petroleum products – Determination of pour point (available in English only) !SO 31 04, 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
3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 silicone insulating liquids liquid organopolysiloxanes whose molecular structure consists mainly of linear chains of alternating silicon and oxygen atoms, with hydrocarbon groups attached to the silicon atoms 3.2 silicone transformer liquid Type T1 polydimethyl siloxane, without additives, primarily for use in transformers NOTE 1 When tested in accordance with the methods specified in Clause 8, silicone Type T1 transformer liquid should comply with the requirements given in Table 1 of this standard. NOTE 2 According to IEC 61 039, silicone Type T1 is classified as L-60836-1 and according to IEC 61 1 00 as Class K3. 4 Properties 4.1 General properties Silicone liquid for transformers (Type T1 ) has high flash and fire points and is therefore difficult to ignite. If combustion occurs, heat release rate is much lower than that of hydrocarbon oils. In addition to use at similar working temperatures to those of transformers containing mineral transformer oil, silicone insulating liquid (Type T1 ) may also be used in appropriately designed electrotechnical equipment operating at higher temperatures. The solubility of water in silicone liquids is greater than in mineral oils. Other physical characteristics which are important for the design of electrotechnical equipment, e.g heat transfer, may also be different from those of mineral transformer oil and will need to be taken fully into account by the designer. 4.2 Properties relating to health, safety and environment (HSE) 4.2.1 Handling Silicone liquids degrade in nature to simple, naturally occurring substances. Their handling is not hazardous to health. Direct contact with the eyes may cause slight irritation. Safety glasses should be worn to avoid splashing the eyes. In the case of eye contact, irrigation with large quantities of clean running water should relieve any irritation. If irritation persists, seek medical advice.
5 General delivery requirements and identification Transport of silicone insulating liquid shall be in clean hermetically sealed containers whose lining does not interact with the contents. Each container shall display the following information: – number of this standard; – supplier’s designation; – batch number; – any notices required by local regulatory authorities. NOTE Electrotechnical equipment filled with silicone insulating liquid should be labelled in accordance with the requirements of the electrotechnical equipment standard in respect of the insulating liquid. 6 Storage and maintenance Storage should preferably be indoors and must be in sealed containers to prevent ingress of moisture and dirt. If accidentally contaminated by water and/or solid particles during storage, the liquid can usually be restored to acceptable quality by the procedures described in IEC 60944.