1.1 本试验方法描述了新的电气绝缘液体以及电缆、变压器、油断路器和其他电气设备中使用或随后使用的液体的试验。 1.2 本试验方法提供了在45至65 Hz的商业频率下进行仲裁试验的程序。 1.3 如果需要进行精度要求较低的常规测定，则允许对本试验方法进行某些修改，如第节所述 16 到 24 . 1.4 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 具体警告见 11.3.3 . 1.6 环保局和许多国家机构已将汞指定为一种有害物质，可导致神经系统、肾脏和肝脏损害。汞或其蒸汽可能对健康有害，并对材料具有腐蚀性。处理汞和含汞产品时应小心。有关详细信息，请参阅适用的产品材料安全数据表（MSDS）和美国环保局网站:http://www.epa.gov/mercury/faq.htm了解更多信息。 用户应意识到，州法律可能禁止向您所在州销售汞和/或含汞产品。 ====意义和用途====== 4.1 损耗因数（或功率因数）- 这是一种测量电绝缘液体在交变电场中使用时的介电损耗和作为热量耗散的能量的方法。低损耗因数或功率因数表示交流介质损耗低。损耗因数或功率因数可作为质量控制的一种手段，并可作为因服务中的污染和劣化或搬运导致的质量变化的指示。 4.1.1 损耗特性通常根据损耗因数（损耗角的正切）或功率因数（损耗角的正弦）进行测量，可以表示为十进制值或百分比。 对于小于等于0.05的十进制值，耗散因子和功率因子值在大约千分之一的范围内彼此相等。一般来说，由于状况良好的绝缘油的损耗因数或功率因数的十进制值低于0.005，因此可以认为这两个测量值（项）可以互换。 4.1.2 耗散因子之间的精确关系( D )和功率因数( PF )由以下等式得出: 的报告值 D 或 PF 可以表示为十进制值或百分比。例如: 4.2 相对介电常数（介电常数）- 绝缘液体通常单独或与固体绝缘材料结合使用，用于将电网的组件彼此绝缘和与地面绝缘，或用作电容器的电介质。 对于首次使用，通常需要较低的相对介电常数值，以便使电容尽可能小，与可接受的化学和传热特性一致。然而，相对介电常数的中间值有时可能有利于在液体可与之串联的液体和固体绝缘材料之间实现更好的交流电场电压分布。当用作电容器中的电介质时，希望具有较高的相对介电常数值，以便电容器的物理尺寸尽可能小。 4.3 测试方法中给出了与介电测量技术和介电损耗源相关的理论 D150型 .

1.1 This test method describes testing of new electrical insulating liquids as well as liquids in service or subsequent to service in cables, transformers, oil circuit breakers, and other electrical apparatus. 1.2 This test method provides a procedure for making referee tests at a commercial frequency of between 45 and 65 Hz. 1.3 Where it is desired to make routine determinations requiring less accuracy, certain modifications to this test method are permitted as described in Sections 16 to 24 . 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. Specific warnings are given in 11.3.3 . 1.6 Mercury has been designated by the EPA and many state agencies as a hazardous material that can cause nervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and the EPA's website: http://www.epa.gov/mercury/faq.htm for additional information. Users should be aware that selling mercury and/or mercury containing products into your state may be prohibited by state law. ====== Significance And Use ====== 4.1 Dissipation Factor (or Power Factor)— This is a measure of the dielectric losses in an electrical insulating liquid when used in an alternating electric field and of the energy dissipated as heat. A low dissipation factor or power factor indicates low ac dielectric losses. Dissipation factor or power factor may be useful as a means of quality control, and as an indication of changes in quality resulting from contamination and deterioration in service or as a result of handling. 4.1.1 The loss characteristic is commonly measured in terms of dissipation factor (tangent of the loss angle) or of power factor (sine of the loss angle) and may be expressed as a decimal value or as a percentage. For decimal values up to 0.05, dissipation factor and power factor values are equal to each other within about one part in one thousand. In general, since the dissipation factor or power factor of insulating oils in good condition have decimal values below 0.005, the two measurements (terms) may be considered interchangeable. 4.1.2 The exact relationship between dissipation factor ( D ) and power factor ( PF ) is given by the following equations: The reported value of D or PF may be expressed as a decimal value or as a percentage. For example: 4.2 Relative Permittivity (Dielectric Constant)— Insulating liquids are used in general either to insulate components of an electrical network from each other and from ground, alone or in combination with solid insulating materials, or to function as the dielectric of a capacitor. For the first use, a low value of relative permittivity is often desirable in order to have the capacitance be as small as possible, consistent with acceptable chemical and heat transfer properties. However, an intermediate value of relative permittivity may sometimes be advantageous in achieving a better voltage distribution of ac electric fields between the liquid and solid insulating materials with which the liquid may be in series. When used as the dielectric in a capacitor, it is desirable to have a higher value of relative permittivity so the physical size of the capacitor may be as small as possible. 4.3 Theory relating to dielectric measurement techniques and to sources of dielectric loss is given in Test Methods D150 .