1. Screw-Type Fuse (RL Series)

This type of fuse adopts a quartz sand filled fuse cylinder with the fuse element embedded inside. When the fuse element blows under fault current, the generated electric arc contacts the surrounding quartz sand and gaps, achieving rapid cooling and arc extinction. A color-coded indicator is installed at one end for operational monitoring, with different colors corresponding to different rated current specifications. The indicator pops out once the fuse operates, providing a clear visual blow signal. With a rated current range of 5A to 200A, screw-type fuses are widely used for branch circuits with high short-circuit current and working environments containing flammable gases.

2. Filled Cartridge Fuse (RT Series)

Belonging to the current-limiting fuse category, this product consists of a quartz sand filled ceramic fuse tube, contact components and silver-plated copper grid fuse elements. It is matched with a special mounting base, such as a base equipped with an isolation disconnector or an integrated fuse isolation knife base, and operated through a manual mechanical structure. Its rated current covers 50A to 1000A, making it suitable for circuit scenarios with high short-circuit current as well as industrial sites with flammable gas hazards.

3. Non-Filled Cartridge Fuse (RM Series)

This fuse features a fiber-made fuse tube and adopts variable cross-section zinc alloy sheets as the fuse element. When the fuse element melts under overcurrent or short-circuit conditions, the high temperature generated decomposes part of the fiber tube to produce high-pressure gas, which quickly extinguishes the electric arc. Thanks to its simple structure, reliable protection performance and convenient installation and use, this type of fuse is generally applied in combination with knife switches.

4. Filled Enclosed High-Speed Fuse (RS Series)

It is a fast-response protective fuse composed of a fuse tube, fixed contact base, operation indicator and special fuse element. The fuse element adopts a special cross-section or mesh structure and is disposable without replaceable parts. Relying on its extremely fast breaking response speed, it is mainly applied to protect semiconductor rectifier components from current damage.

5. Classification by Different Criteria

By operating voltage, fuses are divided into high-voltage fuses and low-voltage fuses.

By protection objects, they can be classified into fuses for transformers and general electrical equipment, voltage transformer dedicated fuses, power capacitor protection fuses, semiconductor component protection fuses, motor protection fuses and household electrical appliance protection fuses.

By structural form, they are categorized into open-type, semi-enclosed, cartridge-type and expulsion-type fuses.

6. Open-Type Fuse

With an ultra-simple structural design, its fuse element is completely exposed to the air and fixed by porcelain supports without closed protective structures. It is applicable to low-voltage outdoor working conditions. Obvious sound and light phenomena will be generated in the air when the fuse cuts off fault current.

7. Semi-Enclosed Fuse

The fuse element is mounted on a porcelain frame and integrally inserted into a porcelain box with metal sockets at both ends. It is designed for low-voltage indoor environments. The outer porcelain box can effectively block the sound and light generated during current breaking, reducing on-site interference and safety risks.

8. Cartridge-Type Fuse

The fuse element is sealed inside an insulating fuse tube, which is then installed on a fixed support or directly connected to the circuit. The fuse tube is a fully closed insulating structure with metal end caps or contact knives at both ends.

Cartridge fuses filled with quartz sand have excellent current-limiting capability during breaking, greatly improving circuit breaking performance, hence named high-breaking-capacity fuses. Vacuum-filled types are defined as vacuum fuses, while SF6 gas-filled types are SF6 fuses, optimized for enhanced arc extinction performance.

Benefiting from the excellent insulation characteristics of quartz sand, vacuum and SF6 gas, cartridge-type fuses are applicable to both low-voltage and high-voltage power systems.

9. Expulsion-Type Fuse

Its fuse element is installed inside an insulating tube made of solid gas-generating materials such as electrical insulating cardboard or organic glass. When short-circuit current passes through the fuse element, instantaneous fusing produces a high-temperature electric arc. The arc rapidly decomposes the solid gas-generating material to produce a large amount of high-pressure gas, which sprays ionized gas and electric arc out from both ends of the tube, accompanied by obvious sound and light effects. The arc extinguishes at the zero-crossing point of alternating current to complete circuit breaking.

The insulating tube is fixed on an insulating support to form a complete fuse assembly. Most products adopt a movable upper-end structure, and the fuse tube will automatically fall off after fault breaking. This type of expulsion fuse is commonly known as a drop-out fuse.