1.1概述本标准分为七条，涵盖安装在普通位置和危险（分类）位置时的阻抗加热要求。第1条规定了范围、目的和典型应用。第2条列出了适用本标准所必需的其他标准的规范性参考。第3条提供了在其他标准中找不到的定义，或为与本标准一起使用而修改的定义。第4条规定了阻抗加热的一般系统要求。第5条规定了绝缘阻抗导体和其他阻抗系统组件的型式试验和常规试验要求。 第6条涵盖标记要求。第7条详细说明了额外的文件要求。本标准还包含附件。附件A提供了参考书目。附录B提供了爆炸性环境中使用区域分类法分类的装置的要求。附录C提供了使用区域分类法对爆炸性环境进行分类的附加要求。附录D涵盖了阻抗加热设计验证方法。附录E提供了与第5条中绝缘阻抗导体测试相关的参考表。附录F提供了计算绝缘电阻的公式。 附件G提供了其他国家标志。1.2范围本标准适用于钢或钢合金管道或设备阻抗加热系统的一般要求、测试、标记和文件要求，其额定值高达132 Vac。这些加热系统部件拟按照CSA C22进行安装。1，《加拿大电气规范》第一部分（CE规范）；NFPA 70，美国国家电气规范®（NEC®）；或任何其他国家电气安装规范（如适用）。本标准适用于拟安装在普通和危险场所的阻抗加热系统。本标准也适用于阻抗加热系统使用的电源连接点和控制方法。 注1:绝缘温度额定值高于105°C的绝缘阻抗导体的认证要求可由认证机构进行特殊调查。注2:有关隔离变压器、配电和控制部件的信息，请参见IEEE Std 844.4/CSA C293。1.3目的本标准规定了阻抗加热系统组件的测试、标记、设计和文件要求。符合此处概述的部件要求的阻抗加热系统旨在:a）保持设计温度；和b）提供电气、热和机械耐久性和可靠性。 1.4典型应用1。4.1通用阻抗加热系统为管道和设备提供加热，以便在以下典型应用中维持或提高温度。1.4.2防凝固系统可用于防止管道或设备中的液体凝固。其中包括水、水溶液、原油、沥青、沥青、金属、硫和其他化学品。加热系统补偿管道热损失，以保持内含物的温度高于凝固点。1.4.3粘度维持系统可用于维持管道或设备中流体的粘度。 稠油和原油等粘性材料通常会被加热，以达到最佳的泵效率和管道尺寸。通常，这些材料被预热到提供所需粘度的温度，并通过设计用于维持该温度的加热管道泵送至目的地。1.4.4工艺加热系统可用于在工艺参数要求时维持流体温度。系统也可用于提高管道或设备中流动的工艺流体的温度，但它们需要增加热输入容量。1.4.5防冷凝系统可用于防止气体材料冷凝。 有些气体在低温下冷凝，需要加热才能在运输过程中保持气态。如果在气体流动期间（例如通过阀门），压力显著降低，则可能还需要增加热输入容量。1.4.6可使用重熔固化液系统重熔固化液。一些加热应用在泵送过程中不需要加热，但只提供热量，以重新熔化管道内容物，并在泵送之前使其达到温度。一个典型的例子是不常使用的装载或卸载管道。

1.1 GeneralThis standard is divided into seven clauses that cover requirements for impedance heating when installed in ordinary locations as well as in hazardous (classified) locations.Clause 1 provides the scope, purpose, and typical applications.Clause 2 lists normative references to other standards that are indispensable in applying this standard.Clause 3 provides definitions that are not found in other standards or have been modified for use with this standard.Clause 4 establishes general system requirements for impedance heating.Clause 5 provides both type and routine testing requirements for insulated impedance conductors and other impedance system components.Clause 6 covers marking requirements.Clause 7 details additional documentation requirements.This standard also contains annexes.Annex A provides bibliographical references.Annex B provides requirements for installations that are in explosive atmospheres classified using the Division method of area classification.Annex C provides additional requirements in explosive atmospheres classified using the Zone method of area classification.Annex D covers impedance heating design verification methodologies.Annex E provides reference tables associated with insulated impedance conductor testing in Clause 5.Annex F provides the formula for calculating insulation resistance.Annex G provides alternative national markings.1.2 ScopeThis standard applies to general, testing, marking, and documentation requirements for impedance heating systems for steel or steel alloy pipe or equipment, rated up to and including 132 Vac. These heating system components are intended for installation in accordance with CSA C22.1, Canadian Electrical Code, Part I (CE Code); NFPA 70, National Electrical Code® (NEC®) in the USA; or with any other national electrical installation code, as applicable. This standard applies to impedance heating systems that are intended to be installed in ordinary and hazardous locations.This standard also applies to power connection points and control methods used with impedance heating systems.NOTE 1— Requirements for certification of insulated impedance conductors with insulation temperature ratings above 105 °C may be considered under a special investigation by an accredited certification body.NOTE 2— Information on isolation transformers, power distribution, and control components can be found in IEEE Std 844.4/CSA C293.1.3 PurposeThis standard provides testing, marking, design, and documentation requirements for impedance heating system components. Impedance heating systems that follow the component requirements as outlined here are intended to:a) Maintain design temperature; andb) Provide electrical, thermal, and mechanical durability and reliability.1.4Typical applications1.4.1General Impedance heating systems provide heating for pipes and equipment in order to maintain or raise the temperature in the following typical applications.1.4.2Solidification prevention Systems can be used to prevent the fluid in a pipe or equipment from solidifying. These include water, aqueous solutions, crude oil, pitch, asphalt, metals, sulfur, and other chemicals. The heating system compensates for pipe heat losses in order to maintain the temperature of the contents above the solidification point.1.4.3Viscosity maintenance Systems can be used to maintain viscosity of a fluid in a pipe or equipment. Viscous materials such as heavy fuel and crude oil are generally heated to achieve optimum pump efficiency and pipe sizes. Usually these materials are preheated to a temperature that provides the desired viscosity and pumped to their destination through heated pipes designed to maintain that temperature.1.4.4Process heating Systems can be used to maintain the temperature of fluids when process parameters require it. Systems can also be used to raise the temperature of process fluids flowing in the pipe or equipment, but they require increased heat input capacity.1.4.5Condensation prevention Systems can be used to prevent gaseous materials from condensing. Some gases condense at low temperature and require heating to maintain their gaseous state during transportation. If pressure is significantly reduced during gas flow, such as through a valve, increased heat input capacity might also be required.1.4.6Re-melting solidified fluids Systems can be used to re-melt solidified fluids. Some heating applications do not require heat during pumping, but only supply heat to re-melt pipe contents and bring them up to temperature prior to pumping. A typical example is an infrequently used loading or unloading pipeline.