请注意:此版本的所有临时修订版将在您购买时提供。绝缘配合，包括电气设备的间隙和爬电距离。1这些要求涵盖了通过使用绝缘协调原则来指定电气设备的空气和表面间距的替代方法。1.2绝缘协调的完整原则包括考虑间隙、爬电距离和用于构成绝缘系统的固体绝缘特性的组合。迄今为止收集的经验数据已用于制定本标准中提出的电气间隙和爬电距离要求。开发固体绝缘评估程序所需的数据仍在收集中。如果可用，本评估程序将添加到本标准中，预计不会影响间隙和爬电距离的要求。 1.3这些要求可作为最终产品标准中规定的所需间距水平的替代品。最终产品标准间距要求可能基于未控制过电压的用途和系统，或者如果控制过电压，则控制水平未知。1.4如果涵盖产品类别的标准特别参考UL 840或其中的任何要求，则这些替代要求适用于特定的产品类别。1.5这些要求的用户可能需要指定过电压水平和将使用的控制方法，并确定产品绝缘系统预计会受到的污染程度。1.6本标准中的测试值不适用于生产线测试。然而，这些要求的用户需要建立一种方法，以确保在产品制造过程中，用于允许间距减小的生产控制仍然有效。 这可能包括样品测试、物理测量或其他等效方法。1.7这些要求的用户还需要确保本标准中未提及的影响因素，如机械运动、导电材料的现场放置和产品损坏，不会影响绝缘协调系统。例如外壳变形、导管或铠装电缆配件移动或现场接线安装不当。必须根据第节“间隙和爬电距离的测量”通过物理测量验证这些位置的间隙和爬电距离是否符合要求。1.8对于包含新特性、特性、组件、材料或系统的产品，或与本标准要求所涵盖的特性、特性、组件、材料或系统不同的产品，以及涉及火灾、触电或人身伤害风险的产品，应使用适当的附加组件和终端进行评估- 保持本标准意图最初预期的安全水平的产品要求。如果产品的特征、特性、组件、材料或系统与本标准的特定要求或规定相冲突，则该产品不符合本标准。应按照制定、修订和实施本标准所采用的方法，提出并采用要求的修订。1.8 2000年9月7日修订

Please note: All interim revisions for this edition available at time of your purchase will be included.Insulation Coordination Including Clearances and Creepage Distances for Electrical EquipmentUL 840Scope1.1 These requirements cover an alternate approach to specifying through air and over surface spacings for electrical equipment through the use of the principles of insulation coordination.1.2 The complete principles of insulation coordination involve the consideration of the combination of clearances, creepage distances, and the properties of solid insulation used to constitute the insulation system. The empirical data gathered thus far has been used to develop the requirements for clearances and creepage distances as presented in this standard. The data needed to develop the evaluation procedure for solid insulation is still being gathered. When available, this evaluation procedure will be added to this standard and is not expected to affect the requirements for clearances and creepage distances.1.3 These requirements may be used as an alternate to required spacing levels specified in end-product standards. The end product standard spacing requirements may be based on use and systems where overvoltages are not controlled, or if controlled, the level of control is unknown.1.4 These alternate requirements are intended to be applied to a particular product category if the standard covering the product category specifically references UL 840 or any of the requirements therein.1.5 Users of these requirements may need to specify the overvoltage levels and the methods of control which will be utilized, and establish the pollution degree to which the product insulation system will be expected to be subjected.1.6 It is not intended that the test values in this standard be employed for production line testing. However, users of these requirements will need to establish a means to ensure that production controls applied to permit the spacing reduction remain in effect during the manufacture of the product. This could include sample testing or physical measurements or another equivalent means.1.7 Users of these requirements will additionally need to ensure that influencing factors not addressed in this standard, such as mechanical movement, field placement of conductive material, and product damage, will not affect the system for insulation coordination. Examples are the deformation of the enclosure, movement of the fittings for conduit or armored cable, or the improper installation of field wiring. Clearances and creepage distances at those locations must be verified for compliance by physical measurement in accordance with Section, Measurement of Clearance and Creepage Distances.1.8 A product that contains features, characteristics, components, materials, or systems new or different from those covered by the requirements in this standard, and that involves a risk of fire or of electric shock or injury to persons shall be evaluated using appropriate additional component and end-product requirements to maintain the level of safety as originally anticipated by the intent of this standard. A product whose features, characteristics, components, materials, or systems conflict with specific requirements or provisions of this standard does not comply with this standard. Revision of requirements shall be proposed and adopted in conformance with the methods employed for development, revision, and implementation of this standard.1.8 revised September 7, 2000