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

Maintenance Procedure for Low-Voltage Power Distribution FacilitiesLow-voltage power distr ibution facilities refer to the infrastructure that delivers electrical power from a power supply room to end-user equipment, typically including distribution cabinets, cables, and wiring. To ensure the normal operation of these facilities and guarantee user safety and power supply quality, regular maintenance and servicing are essential. This article provides a detailed introduction to the maintenance pro

Low-Voltage Electrician Safety Operating Procedures1. Safety Preparation Before performing any low-voltage electrical work, personnel must wear approved protective equipment, including insulating gloves, insulating boots, and insulating workwear. Carefully inspect all tools and equipment for proper operation. Report any damage or malfunction immediately for repair or replacement. Ensure adequate ventilation at the worksite. Avoid prolonged work in confined spaces to prevent fire hazards or poiso

1. Ring Main Unit (RMU) and Transformer SubstationThe ring main unit (RMU) and transformer substation is a critical terminal in a distribution ring network system. The operational status of this terminal is directly affected by the performance of the distribution ring network system. Therefore, this section discusses the advantages, system composition, and key characteristics of the distribution ring network.1.1 Advantages of RMU and Transformer SubstationDue to technological limitations, radial

Differences Between Ring Main Units (RMUs) and SwitchgearIn power systems, both ring main units (RMUs) and switchgear are common distribution equipment, but they differ significantly in function and structure. RMUs are primarily used in ring-fed networks, responsible for power distribution and line protection, with the key feature being multi-source interconnection through a closed-loop ring network. Switchgear, as a more general-purpose distribution device, handles power reception, distribution

Currently, China's medium-voltage distribution networks predominantly operate at 10kV. With rapid economic development, power loads have surged, increasingly exposing the limitations of the existing power supply methods. Due to the outstanding advantages of 24kV high-voltage switchgear in meeting higher load capacity demands, it has quietly gained traction within the industry. Following the State Grid Corporation's "Notice on Promoting the 20kV Voltage Level," the 20kV voltage class has seen a r

Solid-State Transformers (SST): Enabling Intelligent, Efficient, and Flexible Power SystemsThe solid-state transformer (SST), also known as an Electronic Power Transformer (EPT), is a static power conversion device that integrates power electronic circuitry with high-frequency energy transfer based on electromagnetic induction. It enables the transformation of electrical energy from one set of voltage, current, and frequency characteristics to another—while offering far greater control and funct

Solid-state transformers (SST) offer high efficiency, reliability, and flexibility, making them suitable for a wide range of applications: Power Systems: In the upgrade and replacement of traditional transformers, solid-state transformers show significant development potential and market prospects. SSTs enable efficient, stable power conversion along with intelligent control and management, helping to enhance the reliability, adaptability, and intelligence of power systems. Electric Vehicle (EV)

I. Fuse Structure and Root Cause AnalysisSlow Fuse Blowing:From the design principle of fuses, when a large fault current passes through the fuse element, due to the metal effect (certain refractory metals become fusible under specific alloy conditions), the fuse first melts at the soldered tin ball. The arc then rapidly vaporizes the entire fuse element. The resulting arc is quickly extinguished by quartz sand.However, due to harsh operating environments, the fuse element may age under the comb

Common Causes of Fuse BlowingCommon reasons for fuse blowing include voltage fluctuations, short circuits, lightning strikes during storms, and current overloads. These conditions can easily cause the fuse element to melt.A fuse is an electrical device that interrupts the circuit by melting its fusible element due to heat generated when current exceeds a specified value. It operates on the principle that, after an overcurrent persists for a certain period, the heat produced by the current melts

1. Fuse MaintenanceFuses in service should be regularly inspected. The inspection includes the following items: Load current should be compatible with the rated current of the fuse element. For fuses equipped with a fuse blown indicator, check whether the indicator has actuated. Check the conductors, connection points, and the fuse itself for overheating; ensure connections are tight and making good contact. Inspect the fuse exterior for cracks, contamination, or signs of arcing/discharge. Liste