The GN27-40.5 series indoor high-voltage isolation switch is used in a three-phase power system with a rated voltage of 35kVand AC 50Hz, as a means of connecting and conveing lines when there is electricity but no load. is product is equipped with CS6-2 type manual operating mechanism, and when equipped with D, it is equipped with CS6-l type manual operating mechanism.

1.Model and meaning

2.Normal environmental conditions for use

Altitude not exceeding 1000m;

The ambient temperature should not exceed+40 ° C and should not be lower than -10 ° C;

Relative humidity: daily average not exceeding 95%, monthly average not exceeding 90%;

Water vapor pressure: daily average not exceeding 2.2x10-3Mpa, monthly average not exceeding 1.8x10-3Mpa;

A place without harmful gases such as re, explosion, metal corrosion, Insulation damage, and conductive dust;

No frequent and intense vibrations.

3.Main technical parameters

4.Structure and principle

This product is a three Pole common chassis switch with a veical rotating blade, consisting of a chassis, Insulators, and conductive pas. The chassis is formed from steel plates and welded with channel steel, and is equipped with a rotating shaft. Six post insulators or three post insulators and three sleeves are xed on the chassis, with each two forming a pole, with a center to center distance of 540mm and a phase to phase center to center distance of 460mm. ere are three pull rod insulators installed on the rotating shaft, which are used to operate the opening and closing movements of the three pole contact blades. The conductive pa consists of a contact, a contact blade, and a contact seat. The static contact on the fracture side is a swinging multi contact structure with contact ngers, which are compressed by spring steel wires and can swing up and down. Each pole has 2 contact blades mounted on the contact seat and compressed with springs.

When the switch is opened, the operating lever drives the rotating shaft to rotate, causing the pull rod insulator to push the contact blade upwards, separating the contact blade from the corner sole. e contact blade rotates around the contact seat, and the contact also rotates upwards to the opening position under the driving of the contact blade.

A switch with a grounding knife is equipped with a mechanical interlocking device between the main knife and the grounding knife to prevent accidental operation.

5.Installation and adjustment

This series of isolation switches can be installed horizontally, veically, or diagonally, but the installation position should be such that the contact blade tends downwards when opened.

Before installation, carefully clean the dust and di on the switch, inspect the contact suace and terminals, and apply a layer of industrial Vaseline.

The product is equipped with CS6-2 manual operating mechanism, and when equipped with D, it is equipped with CS6-I manual operating mechanism. When installing the toggle arm switch, the user should provide their own drill to x it.

Clean and apply industrial Vaseline to the grounding point during installation, and properly ground it.

Working principle of high-voltage isolation switch

Analysis of High Voltage Isolation Switch Materials

Materials Used in High Voltage Isolating Switches: An In-Depth Analysis

High-voltage isolating switches are essential components in electrical transmission and distribution systems, providing safe operation and maintenance by isolating specific sections of a power circuit. These switches work under extreme conditions, including high electrical stress, environmental challenges, and mechanical wear. The performance and durability of high-voltage isolating switches largely depend on the materials used in their construction. This article explores the various materials used in the fabrication of high-voltage isolating switches, highlighting their properties, functions, and why they are chosen for these critical applications.

The Role of Materials in High-Voltage Isolating Switches

The materials used in high-voltage isolating switches must withstand not only high mechanical and electrical stress but also environmental conditions such as humidity, temperature fluctuations, and corrosion. Each component of the isolating switch, including the contacts, Insulators, actuators, and enclosures, requires specific material properties to ensure efficient and safe operation.

High-voltage isolating switches perform a key role in disconnecting circuits without causing arcs or damaging the system. Therefore, understanding the materials that comprise these switches can help in the design of safer and more reliable electrical systems.

1. Contact Materials

The contacts of high-voltage isolating switches are crucial for their performance. These components are responsible for making or breaking the electrical connection. As high-voltage switches are often required to operate under load, the contacts need to be made of materials that offer both excellent electrical conductivity and durability. The following materials are commonly used:

• Copper (Cu):Copper is one of the most common materials used for electrical contacts due to its excellent electrical conductivity, corrosion resistance, and mechanical properties. Copper contacts ensure minimal electrical resistance when the switch is closed, allowing for efficient power transmission. However, copper can oxidize over time, which may increase the risk of arcing during operation.

• Copper Alloys:Pure copper can degrade due to high temperatures and oxidation. To overcome this, copper alloys such as copper-tungsten (Cu-W) or copper-silver (Cu-Ag) are used in some high-voltage switches. These alloys enhance the material’s hardness, thermal conductivity, and resistance to arcing. Copper alloys also offer better mechanical strength than pure copper, ensuring the longevity and reliability of the switch.

• Silver (Ag):Silver is another excellent material for contacts due to its superior electrical conductivity. Silver contacts are often used in high-voltage isolating switches where low contact resistance is required. However, silver is soft and can wear down over time under mechanical stress, so it is often used in conjunction with other materials to provide better durability.

• Tungsten (W):Tungsten is known for its ability to withstand high temperatures and resist wear. Tungsten contacts are often used in switches that need to handle high currents or switch under difficult conditions. Tungsten’s high melting point makes it an excellent material for preventing arcing when contacts are separated.

2. Insulating Materials

The insulators in high-voltage isolating switches are designed to prevent the flow of electricity between conductors and ensure that parts of the switch are safely isolated. Insulation is crucial to prevent electrical leakage and protect both operators and the equipment. Common materials used for insulators in these switches include:

• Porcelain:Porcelain is one of the most widely used insulating materials in high-voltage systems. It has excellent dielectric properties, allowing it to resist high voltages without breaking down. Additionally, porcelain is strong, durable, and resistant to environmental factors such as temperature fluctuations and UV radiation. However, porcelain can be brittle and may crack under mechanical stress, which is why it is often used in specific designs that provide adequate support.

• Glass:Glass insulators are commonly used for their transparency, ease of inspection, and high dielectric strength. Glass can withstand high mechanical stress and is particularly useful in outdoor applications where durability and environmental resistance are required. Although glass is resistant to corrosion, it can break under impact, which is a limitation in some applications.

• Polymer (Composite) Insulators:Polymer-based insulators are increasingly used in high-voltage isolating switches due to their lightweight, high mechanical strength, and excellent electrical insulating properties. Composite Insulators are made from a combination of materials such as fiberglass and silicone rubber. These insulators offer better resistance to cracking and contamination compared to traditional porcelain and glass insulators. They are particularly useful in environments where moisture or dust accumulation can degrade the performance of other insulators.

• Epoxy Resin:Epoxy resin is another material used for insulation in high-voltage isolating switches, particularly in the construction of certain internal components like bushings and insulating barriers. Epoxy resin is known for its high dielectric strength and ability to withstand chemical corrosion, making it ideal for switches in harsh environments.

3. Actuator and Mechanism Materials

The actuator and mechanical components of high-voltage isolating switches must be durable and capable of handling the mechanical stresses involved in opening and closing the switch. These components often operate in extreme environments, requiring materials that offer strength, durability, and resistance to wear.

• Steel:Steel is commonly used in the construction of the mechanical parts of the isolating switch, including the frame, levers, and actuators. Steel offers high tensile strength, making it capable of handling the mechanical loads placed on the switch. Stainless steel is often chosen for its corrosion resistance, ensuring that the switch can continue operating even in moist or corrosive environments.

• Aluminum Alloys:Aluminum alloys are used in the construction of certain components of the isolating switch due to their lightweight properties and corrosion resistance. Aluminum is often used for housings, covers, and other non-load-bearing components. Its ease of fabrication also makes it a popular choice for switch manufacturers.

• Bronze:Bronze, an alloy of copper, is sometimes used in the moving parts of high-voltage isolating switches because of its excellent resistance to wear and corrosion. Bronze is commonly used for components that will undergo frequent movement or require long service life.

4. Arc Suppression Materials

When a high-voltage isolating switch opens, there is always the risk of an electrical arc forming between the contacts. Arcing can lead to equipment damage and even pose a safety hazard. To mitigate this risk, arc suppression materials are often incorporated into the switch design.

• Arc Chutes:Arc chutes are often used to extinguish arcs by rapidly cooling the arc and guiding it away from the contacts. Materials like ceramic and composite resins are used in arc chutes for their ability to absorb and dissipate the heat generated by the arc.

• Silicone Rubber:Silicone rubber is often used in arc suppression due to its excellent dielectric strength, high resistance to heat, and durability. It can be used in combination with other materials to create arc extinguishing barriers.

5. Enclosure and Housing Materials

The enclosure or housing of high-voltage isolating switches must be robust enough to protect the internal components from environmental damage, such as moisture, dust, and temperature extremes. The materials used for housings need to provide insulation, durability, and mechanical protection.

• Polycarbonate:Polycarbonate is often used in the housings of isolating switches due to its high impact resistance, UV stability, and electrical insulating properties. It is transparent, allowing for easy visual inspection of the switch’s condition.

• Steel and Stainless Steel:The outer housing of the switch is frequently made from steel or stainless steel, both of which offer durability and protection against physical impacts. Stainless steel, in particular, is chosen for its resistance to corrosion, which ensures that the switch remains functional in harsh outdoor environments.

Conclusion

The materials used in high-voltage isolating switches are selected for their specific properties that ensure the efficient, safe, and reliable operation of the switch in demanding electrical environments. From the contact materials such as copper alloys and tungsten to the insulators made of porcelain, polymer, and epoxy resin, each material serves a critical purpose in ensuring the switch functions properly under high voltage and mechanical stress. The selection of appropriate materials is essential for the longevity and performance of isolating switches, which play a crucial role in the safety and maintenance of electrical power systems worldwide.