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Recently, three IEC standards on insulators, led by China for the first time, have been officially published. These standards primarily address the coupling markings, dimensions, and tests of insulator end fittings, specifically including IEC 60120:2020, IEC 60372:2020, and IEC 60471:2020. These three standards were jointly completed under the leadership and coordination of numerous experts from the National Technical Committee on Insulators of China (SAC/TC80). The publication of these standard

There is extensive literature on the analysis of overvoltage at transformer neutral points under lightning surge conditions. However, due to the complexity and randomness of lightning waves, an accurate theoretical description remains elusive. In engineering practice, protective measures are typically determined based on power system codes by selecting appropriate lightning protection devices, with abundant supporting documentation available.Transmission lines or substations are susceptible to l

Standards for Surge Arresters Used in Cable Auxiliary Equipment GB/T 2900.12-2008 Electrotechnical Terminology – Surge Arresters, Low-Voltage Surge Protective Devices, and ComponentsThis standard defines specialized terminology for surge arresters, low-voltage surge protective devices, and their functional components. It is primarily intended for use in drafting standards, writing technical documents, translating professional manuals, textbooks, journals, and publications. GB/T 11032-2020 Metal-

IntroductionAtmospheric lightning strikes on overhead lines, bare conductors, or metallic structures in outdoor substations, as well as overvoltages caused by switching operations of equipment and networks (switching overvoltages), pose significant hazards to electrical equipment. To protect equipment and facilitate insulation coordination,surge arresters(also known as "lightning arresters") must be installed at the incoming/outgoing points of overhead lines and in close proximity to transformer

Characteristics and Materials of Fuse ElementsThe materials selected for fuse elements must possess a specific set of properties. They need to have a low melting point, ensuring that the fuse will melt quickly when an excessive current flows through it, thereby interrupting the circuit and protecting the electrical system. Additionally, these materials should exhibit low ohmic loss to minimize energy dissipation during normal operation. High electrical conductivity (equivalent to low resistivity

What is Valve Type Lightning Arrester?DefinitionA lightning arrester that comprises single or multiple gaps connected in series with a current - controlling element is referred to as a lightning arrester. The gap between the electrodes blocks the flow of current through the arrester, except when the voltage across the gap exceeds the critical gap flashover voltage. The valve - type arrester is also called a gap surge diverter or a silicon - carbide surge diverter with a series gap.Construction o

Acoustic Emission: This method can be effectively employed to detect hazardous cracks in support insulators on - site in an offline mode. It is well - suited for identifying damages caused by mechanical stress, such as fatigue - related cracks. However, it is ineffective for detecting defects like pores. Non - destructive Ultrasound: Relying on the ultrasound impulse method, this technique works offline by exciting the insulator and its defects through the injection of short acoustic impulses.

An AC surge protector (also known as a surge protection device or SPD) may frequently blow for several reasons, which can be related to design, installation, maintenance, and external environmental factors. Below are some common causes and explanations:1. Poor Quality of the Surge Protector Insufficient Voltage Rating: If the surge protector's rated voltage or maximum continuous operating voltage (UC) is lower than the actual system voltage or the highest possible fault voltage, it may be subjec

Composition of Composite InsulatorsComposite insulators (also known as synthetic insulators) are modern electrical insulation devices widely used in high-voltage transmission lines and substations. They combine the advantages of traditional porcelain and glass insulators while overcoming some of their limitations. A composite insulator primarily consists of the following components:1. Core Rod Material: Typically made from glass fiber-reinforced plastic (FRP, Fiber Reinforced Plastic), or someti

The criteria for replacing insulator strings on high-voltage towers is not solely based on the number of broken pieces nor determined by a single calculation. Instead, it involves a comprehensive consideration of multiple factors. Below are the main considerations that determine whether an insulator should be replaced: Physical Damage: If there is evident physical damage to the insulator, such as fractures, cracks, surface spalling, or skirt damage, then even if the predefined number of broken p