绝缘液.使用过和未使用过绝缘油中潜在腐蚀硫的探测用试验方法

[中文适用范围]： 此国际标准规定了一种检测新和旧矿物绝缘油中潜在腐蚀性硫的测试方法。最近的因腐蚀性硫导致的故障大多与绕组纤维素纸内部和表面形成硫化铜沉积物有关。该测试方法使用一根包裹一层纸的铜导体，浸入油中并加热，以评估油产生硫化铜并将其转移到纸层的能力。裸露铜上硫化铜的生长可能导致油中存在导电颗粒，这些颗粒可作为电晕放电的核心，并可能导致故障。其他测试方法包括将裸露铜条浸入油中加热以检测油对铜的腐蚀行为。ASTM D1275方法B也用于此测试，Annex A中包含了一种使用低油体积的修改程序。有纸和无纸的测试被认为是互补的，可能会导致不同的结果。 [外文原描述]： IEC 62535:2008 specifies a test method for detection of potentially corrosive sulphur in used and unused mineral insulating oil. Most recent failures due to corrosive sulphur are related to the formation of copper sulphide deposits in and on the surface of winding cellulosic paper. The test method uses a copper conductor, wrapped with one layer of paper, immersed in the oil and heated to evaluate the capability of the oil to yield copper sulphide and transfer it to paper layers. The growth of copper sulphide on bare copper may cause the presence of conductive particulates in the oil, which can act as nuclei for electrical discharge and may lead to a fault. Other test methods exist using a bare copper strip immersed in oil and heated to detect the corrosive behaviour of oil against copper. ASTM D1275 Method B is also used for this test and a modified procedure using low oil volumes is included in Annex A. Tests with and without paper are considered as complementary and may lead to different results.