Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

35kV Outdoor Wind-Resistant High-Voltage Disconnector— Suitable for wind farms, overhead line pole-mounted applications, and substation installations.Model series: GW5-40.5 outdoor high-voltage disconnector (hereinafter referred to as “disconnector”).This disconnector is designed for use in 50Hz, 35kV power systems to open or close circuits under no-load voltage conditions. The pollution-resistant variant meets the requirements of users in heavily polluted areas and effectively mitigates polluti

Interlocking the disconnector (isolator) control wiring with its associated circuit breaker can effectively prevent the inadvertent opening or closing of the disconnector under load. However, during operations involving bus-side and line-side disconnectors, human error may lead to an incorrect sequence of operations—an action strictly prohibited by switching principles and a known cause of power system accidents.To prevent such sequence errors, for substations and power plants that do not employ

IEEE Std C37.20.9™ defines the design, testing, and installation requirements for metal-enclosed gas-insulated switchgear (MEGIS) using gas at pressures above ambient as the primary insulation medium for alternating current systems rated from 1 kV to 52 kV. This includes, but is not limited to, circuit breakers, switches, bushings, busbars, instrument transformers, cable terminations, meters, and control/protection relays. In these switchgear assemblies, vertical compartments—some or all of the

"Faults of catenary isolating switches" are common failures in current traction power supply operations. These faults frequently result from mechanical failures of the switch itself, control circuit malfunctions, or remote control function failures, leading to refusal-to-operate or unintended operation of the isolating switch. Therefore, this paper discusses common faults of catenary isolating switches during current operations and the corresponding handling methods after fault occurrence.1.Comm

The GW8 isolating switch is a critical piece of equipment in power systems and is primarily used in the following applications:Applications in Power Systems:The GW8 isolating switch is widely employed in power plants, substations, and transmission and distribution lines. In power plants, it isolates the connection between generators and busbars or transformers, facilitating generator startup, shutdown, and maintenance. In substations, it isolates busbars or transformers operating at different vo

Installation Requirements for Isolating SwitchesBefore installing an isolating switch, a thorough visual inspection must be carried out. The main items to check include:(1) Verify that the model and specifications of the isolating switch match the design requirements.(2) Inspect all components for damage and check whether the blade or contacts are deformed. If deformation is found, it should be corrected.(3) Examine the contact condition between the movable blade and the contacts. Any copper oxi

Transformer Neutral Grounding Disconnector: Function, Principle, Structure, Operation, and MaintenanceA transformer neutral grounding disconnector is an electrical device used to isolate the neutral point of a power transformer. Its primary purpose is to protect both the transformer and the overall power system, ensuring safe and stable operation.I. Functions of the Transformer Neutral Grounding DisconnectorTransformer ProtectionOne of the key roles of the neutral grounding disconnector is to sa

The following are methods for handling accidents and abnormalities related to isolating switches:(1) If an isolating switch fails to operate (refuses to open or close), take the following steps:① For mechanically operated isolating switches that fail to open or close, check whether the circuit breaker is open, whether the mechanical interlock of the isolating switch has been released, whether the transmission mechanism is jammed, and whether the contacts are rusted or welded. Gently wiggle the o

When performing switching operations, operating personnel must carefully verify that the circuit breaker is indeed in the open position. For three-pole interlocked isolating switches, all three phases must move simultaneously, with a maximum allowable vertical discrepancy of no more than 3 mm, before any opening or closing operation of the isolating switch is permitted.1. Key Points for Closing an Isolating SwitchFor manual operation, operating personnel should first remove the interlock pin bef

In substations, the number of isolating switches is generally 2 to 4 times that of circuit breakers. Due to their large quantity, the workload for installation and commissioning is considerable. For voltage levels below 110 kV, the GW4-type isolating switch serves as the dominant equipment. If the installation workmanship and mechanical dimensional adjustments of the isolating switch do not meet requirements, issues such as incomplete opening/closing, overheated contacts, or even porcelain insul