T/JSEE 007-2018 The calibration specification for DC demagnetization instrument for power transformers
T/JSEE 007-2018 The calibration specification for DC demagnetization instrument for power transformers
Basic Information
Scope
Main technical content: This standard specifies the general technical requirements, metrological characteristics, calibration conditions, calibration items and methods, calibration result expression, and recalibration time intervals for DC demagnetizers used in power transformers. This standard applies to the calibration of DC demagnetizers for power transformers. The standard consists of 9 chapters. **Chapter 1: Scope** **Chapter 2: Normative References** **Chapter 3: Terms and Definitions** **Chapter 4: General Technical Requirements for DC Demagnetizers**: Specifies general technical requirements for DC demagnetizers, including their appearance, insulation resistance, dielectric strength, mechanical performance, power frequency and voltage tests. **Chapter 5: Metrological Characteristics**: Specifies measurement range parameters such as initial current, completion current, current stepdown ratio, and current segment steady-state time for DC demagnetizers. It also standardizes current error, time error, and proportional error for DC demagnetizers. **Chapter 6: Calibration Conditions**: Specifies the calibration environment and devices used for DC demagnetizers. **Chapter 7: Calibration Items and Methods**: Standardizes technical performance parameters such as appearance, insulation resistance, dielectric strength, initial current, completion current, current stepdown ratio, and current segment steady-state time for DC demagnetizers. **Chapter 8: Calibration Results**: Specifies the content and format of calibration certificates. **Chapter 9: Recalibration Time Intervals**: Specifies the recalibration time intervals for DC demagnetizers. **Appendix A (Informative):** Provides a schematic diagram of magnetic flux changes in the transformer core during the demagnetization process. **Appendix B (Informative):** Introduces the evaluation of measurement uncertainty. **Appendix C (Informative):** Standardizes the format of the original calibrati