Surge arrester disconnector

A surge arrester disconnector is a device that is designed to disconnect an arrester from the system in the event of a failure of the arrester. Its purpose is to prevent a permanent fault in the system and to provide a visual indication of the failed arrester. The thermal explosive disconnector complies with the IEC 60099-4 standard. The Thermal Explosive Disconnector only operates when a power frequency fault current flows through the device during a fault. It is not activated by surge currents.

Product description

Product introduction:

The overvoltage disconnecting device is a critical safety device integrated with overvoltage arresters to ensure reliable isolation of an overloaded arrester from the electrical system. This device acts as a fail-safe mechanism designed to disconnect the earth lead from the base of the arrester in the event of a fault, thereby preventing further damage and maintaining system integrity.

The disconnector is designed to automatically disconnect at the fault current, while the surge arrester fails under the abnormal conditions and the failed lightning arrester is disconnected.

Note: The last ‘L’ in the designation indicates the load break switch.

L:With disconnector

No L:Without disconnector.

Construction features:

Heat-activated disconnection: Equipped with a heat-activated mechanism that triggers the disconnection when the temperature threshold is reached due to fault current.

Safety and reliability: Ensures that the disconnector operates only under fault conditions and not during normal surge arrester operation.

Durable construction: Built to withstand the mechanical and thermal stresses associated with electrical fault currents.

Easy integration: Designed for compatibility with various surge arrester models, allowing for easy installation and integration.

How it works:

The arrester disconnector is a special device used to protect the arrester in the power system.

Its main function is to isolate the arrester from the system after the arrester has failed and to maintain the normal operating condition of the system.

The operating principle of the arrester disconnector can be summarised as follows

1. Arc extinguishing effect: When the arrester fails, an arc is generated inside the arrester, and then the disconnector extinguishes the arc by its own electrical and mechanical action. This prevents damage to the system due to hysteresis or prolonged arcing.
2. Automatic disconnection: the disconnector is equipped with an internal disconnection switch. When the arrester fails, the disconnector will automatically disconnect from the system, isolating the arrester from the system and protecting the safe and stable operation of the system.
3. Anti-reclosing action: After the disconnector is disconnected, it can not only prevent the arrester from continuing to operate, but also prevent the system from being reconnected. As the failure of the arrester often leads to the instantaneous short circuit of the system, if the system is closed again before the arrester has returned to normal, it will cause greater damage to the system.
4. Energy saving effect: After the disconnector is released, the arrester returns to its normal operating state. This saves energy and improves the efficiency of the system.

In summary, the role of the arrester disconnector is to ensure the safety and stability of the power system, its working principle is to isolate the arrester and the system by electrical and mechanical action, and to prevent the system from reconnecting, so as to protect the safe and stable operation of the system and equipment.

Applicable environmental conditions:

Temperature range: Capable of operating in a wide range of ambient temperatures, typically from -40°C to +60°C, suitable for different climates.

UV and weather resistance: Designed to withstand ultraviolet radiation and other weather-related factors to ensure long-term outdoor performance.

Chemical exposure: Resistant to common environmental chemicals that could affect disconnect performance.

Humidity tolerance: Designed to operate effectively in high humidity conditions, important for high humidity regions.

Applications

Power distribution networks: Surge arrester disconnectors are used in power distribution networks to protect equipment from overvoltage transients caused by lightning strikes or switching operations. They ensure that the surge arrester can be safely disconnected from the system at the end of its life or when maintenance is required, preventing damage to the network.

Transmission lines: In high-voltage transmission systems, surge arrestor disconnectors are critical for protecting transformers, circuit breakers and other critical equipment from voltage surges. They help maintain the stability and reliability of the transmission network by ensuring that overvoltage conditions do not cause equipment failure.

Renewable energy installations: Surge arresters are essential in renewable energy systems such as solar and wind farms, where they protect inverters, transformers and other sensitive equipment from voltage transients. This helps to ensure the continuous and efficient operation of renewable energy sources.

Industrial facilities: Industrial plants and facilities use surge arrestors to protect machinery and electrical equipment from transient surges. This protection is essential to maintain the smooth operation of industrial processes and avoid costly downtime due to equipment damage.

Substations: In electrical substations, surge arrestor disconnectors provide critical protection for transformers and other high-voltage equipment. They help to isolate faulty surge arresters from the system, ensuring that the rest of the substation equipment remains operational and protected.