Surge Arrester Disconnector
Product Overview
Disconnector for lightning arrester is a dedicated safety protection device for surge arresters, installed in series with the arrester. Its primary function is to rapidly isolate a faulty arrester (e.g., internal breakdown or short circuit) from the power grid when a fault occurs, preventing fault escalation. A clearly visible disconnection indicator alerts maintenance personnel to replace the faulty unit. During normal operation, the disconnector remains in a low-impedance state, imposing no effect on the protective performance of the arrester. This device enables maintenance-free, safe operation of surge arresters and is an indispensable component in distribution system lightning protection.
Product Features
2.1 Protection and Operating Performance
Employing a novel thermal-explosive actuation design, the disconnector offers fast response with no risk of spurious operation. It reliably actuates the instant an arrester fault occurs, removing the faulty arrester from the grid and preventing fault escalation that could cause line short circuits or trip events.
Upon actuation, a clearly visible disconnection indicator is formed, enabling operations and maintenance personnel to rapidly identify the fault location without inspecting each arrester individually, significantly improving O&M efficiency.
During normal operation, the disconnector remains in a low-impedance state, imposing no effect on the volt-ampere characteristics or protective performance of the arrester, and does not interfere with the arrester’s discharge process for lightning overvoltages or switching overvoltages.
2.2 Structural and Safety Features
The integrated sealed construction features a housing made of high-strength insulating material with excellent moisture-proof, waterproof, and anti-pollution performance, effectively preventing internal components from moisture ingress and corrosion to extend service life.
The flameless, non-spatter actuation design produces no flammable or explosive hazard during operation, making it suitable for outdoor, indoor, coal mine, chemical plant, and other varied environments with a high level of safety.
Strong compatibility — can be used with all distribution-type, station-type, and line-type surge arresters rated 3 kV and above, requiring no additional modification and allowing convenient installation.
2.3 Environmental and Weather Resistance
Excellent weatherability, capable of operating across a wide temperature range of −40°C to +90°C with no degradation of housing insulation performance or internal component performance at extreme temperatures, and no risk of cracking or embrittlement.
Moisture-proof, waterproof, and salt-fog resistant, ensuring long-term stable operation in humid, dusty, and salt-fog environments. Resistant to rain and condensation erosion; the housing exhibits strong hydrophobicity to effectively prevent surface flashover.
Anti-aging, UV-resistant, and ozone-corrosion resistant, with a service life exceeding 20 years. Maintenance-free operation reduces long-term O&M costs.
Typical Ampere-Second (A·s) Characteristic Parameters
| Current (A) | 800 | 200 | 20 | 5 | 0.5 | 0.05 |
|---|---|---|---|---|---|---|
| Operating Time (s) | 0.01~0.02 | 0.02~0.05 | 0.1~0.2 | 0.5~1.0 | 20~50 | 200~500 |
Scope of Application
Applicable voltage levels: All AC distribution systems rated 3 kV and above, covering low-voltage, medium-voltage, and high-voltage arrester applications.
Applicable scenarios:
Safety protection for distribution-type, station-type, and line-type surge arresters;
Arrester installation applications including outdoor overhead lines, distribution transformers, switchgear cabinets, and cable terminations;
Urban distribution networks, industrial and mining enterprises, new energy (photovoltaic/wind power) step-up substations, and underground coal mine arrester applications;
Surge arrester applications for power grid operation in Europe, the Americas, Japan, and other countries and regions.
Functional purpose: Rapid actuation upon arrester fault to isolate the faulty arrester from the grid, preventing fault escalation; provision of a clearly visible fault indicator for rapid identification and replacement by O&M personnel; no effect on arrester protective performance during normal operation, enabling safe maintenance-free arrester operation.
Operating Conditions
5.1 Standard Operating Conditions
Altitude: ≤2000 m;
Ambient temperature: −40°C to +90°C; equipment operating temperature complies with relevant standards;
Relative humidity: ≤100% (non-condensing);
Environmental conditions: free from corrosive gases, flammable or explosive media, and severe vibration or shock;
Installation method: installed in series with the surge arrester, compatible with arrester installation configurations; installation space must satisfy insulation clearance requirements.
5.2 Special Operating Conditions (Custom Order Required)
Altitude exceeding 2000 m;
Ambient temperature outside the −40°C to +90°C range;
Severely polluted, salt-fog, or chemically corrosive environments;
High-vibration or high-impact operating conditions;
Non-standard current ratings or operating time requirements.
Installation and Maintenance
6.1 Installation Requirements
Before installation, inspect the product appearance: the housing must be free from cracks, damage, and air bubbles; terminal connectors must be intact with no corrosion or deformation.
Clean the surface of the terminal connectors to remove grease, dust, and foreign matter, ensuring the terminals are dry and clean. Install the disconnector in series with the surge arrester in accordance with the arrester manufacturer’s requirements, and torque the terminal connectors to the specified value to ensure a reliable connection.
After installation, verify the mounting orientation of the disconnector and the direction of the disconnection indicator to ensure the indicator is clearly visible and unobstructed after actuation.
6.2 Maintenance Requirements
Periodically inspect the product appearance: the housing must be free from cracks, damage, discharge marks, and contamination accumulation; terminal connections must be firm and secure.
Periodically check the status of the disconnection indicator to confirm the absence of spurious operation or abnormal disconnection. If disconnector actuation is detected, replace the faulty arrester and disconnector promptly.
Clean the product surface to remove accumulated dust and contamination, keeping the housing dry and clean. Avoid exposure to grease and chemical substances that may cause corrosion.
After disconnector actuation, both the arrester and the disconnector must be replaced simultaneously. Reuse of an actuated disconnector is strictly prohibited.
Precautions
The product must be installed, commissioned, and maintained by qualified electrical professionals with distribution work credentials. Operation by non-qualified personnel is strictly prohibited.
The product must be used with surge arresters of the corresponding model and voltage rating. Mismatching with arresters of different specifications is strictly prohibited, as this will result in protection failure and safety incidents.
Unauthorized disassembly or modification of the product is prohibited and will void the warranty and safety certification. Use of non-specified tools to forcibly install or remove terminal connectors is strictly prohibited.
Housing damage during installation is strictly prohibited. Terminal connectors must be torqued to the specified value to prevent poor contact leading to overheating or discharge.
For storage, place in a dry, ventilated, and cool environment away from direct sunlight, high temperatures, humidity, and compression. Contact with sharp objects that may damage the housing is strictly prohibited.
After disconnector actuation, the arrester and disconnector must be replaced immediately. Continued use of a faulty arrester or an actuated disconnector is strictly prohibited.
Applicable Standards and Certifications
International standards: IEC 60099-4 Metal-oxide surge arresters without gaps for a.c. systems; IEC 60099-5 Surge arresters — Disconnectors;
National standards: GB 11032 Metal-oxide surge arresters without gaps for a.c. systems; DL/T 804 Guide for application of metal-oxide surge arresters for AC power systems;
The product has passed type testing by the National High-Voltage Electrical Apparatus Quality Supervision and Inspection Center and complies with national power industry standards.
After-Sales Service
Product warranty period: 18 months from the date of manufacture, or 12 months from the date of commissioning, whichever comes first;
Free repair or replacement for product quality issues occurring within the warranty period;
Technical support, installation guidance, and customization services (special specifications and special operating condition adaptations) are provided.
Document Notes
The technical parameters in this manual are based on standard operating conditions. Special operating conditions require customization to actual requirements. The product technical agreement and type test report shall prevail as the final reference.
Appendix: Product Dimensional Diagram
