GB/T 7252-2001

📋 Scope / 适用范围 ai_extracted

This standard recommends methods for assessing the condition of oil-filled electrical equipment through the analysis of dissolved gases in oil and free gas concentrations, along with suggested further actions to be taken. This standard applies to electrical equipment filled with mineral insulating oil and using paper or laminated pressboard as solid insulating materials, including transformers, reactors, current transformers, voltage transformers, and oil-paper bushings, among others. The conclusions drawn from the analysis results shall be comprehensively evaluated in conjunction with the equipment's structure, maintenance, electrical tests, operating conditions, as well as the prevailing local environmental conditions at the time.

📝 Foreword / 前言 ai_extracted

Analyzing the composition and content of gases dissolved in oil is one of the most effective measures for monitoring the safe operation of oil-filled electrical equipment. The use of gas chromatography to analyze dissolved gases in oil for monitoring the safe operation of oil-filled electrical equipment has over 30 years of practical experience in China. The standard GB/T 7252-1987 "Guide to the Analysis and Diagnosis of Gases Dissolved in Transformer Oil," issued by the former National Bureau of Standards in 1987, has played a significant role in the safe production of electric power and has accumulated rich practical experience. With the development of electric power production and the advancement of science and technology, the analytical methods used, as well as the judgment and interpretation of analytical results, require supplementation and revision. This standard is revised with reference to IEC 60599:1999, but is not equivalent to it, and serves as a revision of GB/T 7252-1987. Main revisions include: 1. In accordance with new regulations on the format of national standard compilation, two chapters, "Normative References" and "Definitions," have been added, and necessary modifications have been made to the chapter structure in line with the content of this standard. 2. The explanation of fault gas generation principles and the analysis of non-fault gas sources have been revised to be more systematic and clear. 3. Different detection intervals have been specified for various types of equipment, which is one of the major new additions in this standard. 4. The "Fault Diagnosis" section has been divided into two chapters: first, determining whether a fault exists—recommending attention values for dissolved gas content and gas generation rates for different equipment; second, further determining the nature and severity of the fault—recommending the most effective domestic judgment methods and the latest methods recommended by IEC 60599:1999. 5. In line with technological developments, the analytical methods have been revised, and relevant content such as estimation of test errors has been added. 6. In the appendices, the latest methods and examples for judging fault types from IEC 60599:1999 and other foreign literature have been added for reference. Appendices A and B of this standard are normative appendices. Appendices C, D, E, and F of this standard are informative appendices. This standard replaces the former national standard GB/T 7252-1987 "Guide to the Analysis and Diagnosis of Gases Dissolved in Transformer Oil" from the date of implementation. This standard was proposed by the former Ministry of Electric Power Industry. This standard was drafted by: China Electric Power Research Institute. Main drafters of this standard: Jia Ruijun, Xue Chendong. This standard is entrusted to China Electric Power Research Institute for interpretation. National Standard of the People's Republic of China Guide to the Analysis and Diagnosis of Gases Dissolved in Transformer Oil GB/T 7252-2001 neq IEC 60599:1999 Replaces GB/T 7252-1987

📚 References & Relations / 引用与关联

🔗 Related Standards / 同类标准