Shu Guang
Shu Guang
Premium electrical components manufactured strictly under ISO9001 and verified by world-leading high-power laboratories.
Wenzhou Shuguang Fuse Co., Ltd. is located in Yueqing, Zhejiang Province, the electrical capital of China. We are a premier power technology enterprise integrating intensive research, precision development, high-capacity production, global sales, and engineering support services. The predecessor of Wenzhou Shuguang Fuse Co., Ltd. was the Yueqing Shuguang Fuse Factory, established in 1992.
Over the past three decades, we have evolved from a localized manufacturing facility into a key global technical supplier of high-voltage and medium-voltage circuit protection devices. Guided by the philosophy of "Development by science and technology, and survival by quality," we continue to introduce innovations in silver element design, sand-filling mechanics, and pressure-sealed ceramic structures.
We work in close cooperation with provincial power utilities across China, and maintain active distribution channels across Southeast Asia, the Middle East, Africa, Europe, and South America, placing our production volume and technical capacity at the forefront of the modern fuse industry.
A deep dive into design principles, metallurgy, thermal-stress management, and arc-quenching kinematics.
Custom Medium Voltage Fuses (CMVFs) protect distribution systems from catastrophic overcurrent events. Our proprietary design features high-purity silver ribbons (99.99% purity) with precise geometric notches to define current flow and melting points. Standard fuses fail under high cyclic loading, but our custom elements utilize the metallurgical 'M-effect' (tin/lead alloy deposits) to induce low-temperature melting during persistent overload conditions, preventing overheating of the surrounding housing.
When an overcurrent activates the silver link, it melts, igniting a high-temperature arc. Our design relies on chemically purified, grain-size-controlled quartz sand ($SiO_2$). During arc extinction, the heat fuses the quartz sand into a solid hollow cylinder called a fulgurite. This process absorbs thermal energy and blocks arc paths in milliseconds. High compaction density prevents internal air voids, protecting against mechanical rupture from high peak-fault pressures.
Our medium voltage fuse bodies are constructed using high-strength glazed alumina porcelain or fiberglass-reinforced epoxy tubes. End caps are joined via premium compression-fit and silver-plated copper contacts, preventing oxidation and moisture ingress. Our hermetic seals protect inner elements from environmental breakdown, maintaining long-term reliability in harsh climates like coastal salt spray, industrial chemical environments, or high-humidity regions.
| Fuse Class/Type | Rated Voltage Range (kV) | Rated Breaking Capacity ($I_1$) | Standards Conformity | Primary Industrial Application |
|---|---|---|---|---|
| DIN Standard Back-Up Fuse-Links | 3.6 kV - 40.5 kV | Up to 63 kA | DIN 43625, IEC 60282-1 | Transformers, Ring Main Units (RMU) |
| Capacitor Protection Fuses (Tail Wire) | 6 kV - 12 kV | Up to 50 kA | IEC 60871-4, GB 15166.5 | Power Capacitor Bank Arrays |
| Motor Protection Fuses (Super-speed) | 3.6 kV - 7.2 kV | Up to 50 kA | IEC 60644, IEC 60470 | Medium Voltage Motors & Starters |
| XRNP Voltage Transformer Protection | 10 kV - 40.5 kV | Up to 100 kA | IEC 60282-1, GB 15166.2 | VT Protection & Switchgear Auxiliary |
Tailored power protection engineered for demanding field conditions and diverse global environments.
Scenario: Offshore Wind Nacelles and Utility-Scale Solar PV Farms.
Inverter systems require fuses with high cyclic load tolerance to withstand power fluctuations. Our custom 12kV and 36kV current-limiting fuses prevent transient faults from damaging valuable switchgear. Additionally, our polymeric insulators offer high resistance to salt spray and UV degradation.
Scenario: Alpine Substations & Nordic Power Distribution Networks.
Standard drop-out fuses can suffer mechanical stress and structural cracks under freezing conditions. Wenzhou Shuguang's custom components are engineered using special ceramic materials and low-temperature grease to ensure reliable mechanical drop-out operation down to -40°C.
Scenario: Low-Noise, Sealed Indoor Switchgear Complexes.
Urban utilities require protective devices that operate without venting hot gases. Our DIN-standard back-up fuses are sealed to contain arc energy within the tube, eliminating toxic gas emissions and loud reports during clearing operations, making them ideal for urban environments.
Anticipating the demands of smart grids, high-power DC distribution, and green energy structures by 2030.
Developing medium voltage fuses with integrated thermal and optical fibers. Real-time temperature and leakage current tracking will allow operators to identify degradation before a fault occurs, reducing unplanned downtime.
With mega-watt chargers for electric trucks and heavy vehicles operating at higher voltages, we are designing high-speed current-limiting fuses tailored to DC systems up to 1500V DC with high breaking capacities.
Transitioning our manufacturing lines to lead-free silver alloy formulations and highly recyclable composite casings. Our goals align with zero-carbon grid development, helping to minimize the environmental footprint of our products.
Our facility is located in Yueqing, Zhejiang, the electrical capital of China. This placement provides a robust ecosystem that helps streamline our manufacturing and shipping processes:
Every fuse we manufacture undergoes testing to verify compliance with major international utility standards.
Wenzhou Shuguang Fuse Co., Ltd. is authorized by the Ministry of Electric Power Industry to manufacture high-voltage protective systems, current-limiting fuses, capacitor protection fuses, and drop-out switches. Our products are fully tested and certified by recognized testing centers, including:
Our quality system is certified under ISO 9001:2000, ensuring full documentation, materials traceability, and rigorous final electrical checks for every production batch.
Our high-performance fuses are designed to meet or exceed the following specifications:
Providing robust circuit protection solutions across diverse industrial environments worldwide.
Expert answers to common engineering questions regarding the selection, customization, and application of MV fuses.
A comprehensive range of high-voltage switches, miniature fuse-links, and polymer components for sub-transmission and distribution grids.
Get in touch with our engineering team to design custom current-limiting fuses and high-voltage circuit protection components tailored to your system specs and environmental conditions.
Contact Our Engineering Team
