Product Overview
The LW9-72.5 is an outdoor high-voltage SF6 circuit breaker engineered for 72.5kV systems with a lightning impulse withstand voltage of 350kV to earth and 350+60kV across the fracture. This insulation rating makes it suitable for substations exposed to lightning surges on overhead lines, where the breaker must withstand impulse voltages from switching and lightning events while maintaining reliable fault clearing capability.
Key Features
- 350kV lightning impulse withstand: Rated lightning impulse withstand voltage of 350kV to earth and 350+60kV across the fracture provides insulation coordination for overhead line entry points and exposed substation installations.
- 160kV power frequency withstand: One-minute power frequency withstand of 160kV to earth and 160+42kV across the fracture ensures insulation integrity under steady-state and switching overvoltage conditions.
- 40kA short-circuit breaking current: Clears fault currents up to 40kA with high-speed operation, protecting equipment from the thermal and mechanical effects of short-circuit faults.
- SF6 gas arc extinguishing: Sulfur hexafluoride gas delivers fast arc quenching and dielectric recovery, maintaining performance across repeated switching operations in outdoor conditions.
- 100kA peak withstand current: Withstands peak short-circuit currents of 100kA, ensuring structural and thermal stability during the initial fault current peak before breaker operation.
- Spring operating mechanism: Spring-charged mechanism provides consistent high-speed contact separation, critical for minimizing arc duration and fault damage during breaker operation.
- ISO9001-2000 certified: Manufactured under ISO9001-2000 quality management. Documentation includes English manuals, test reports, certificates, and wiring diagrams for customs clearance and site commissioning.
Basic Info.
| Model NO. | LW9-72.5 |
| Arc-extinguishing Medium | SF6 |
| Structure | Other |
| Type | Circuit Breaker |
| Certification | ISO9001-2000 |
| Service | OEM/ODM |
| Warranty | 12 Months |
| Rated Voltage | 72.5kv |
| Rated Short-Time Withstand Current | 40ka(3s) |
| Rated Peak Withstand Current | 100ka |
| Cut Back-to-Back Capacitor Bank Curr | 4000A |
| Rated 1 Min Power Frequency Withstand Vo | Fracture:160+42kv to Earth:160kv |
| Specification | Custom |
| Origin | Zhejiang,China |
| Speed | High-Speed Circuit Breaker |
| nstallation | Outdoor Installation |
| Poles Number | Other |
| Function | Circuit-Breaker Failure Protection |
| Product Name | Hv Sulfur Hexafluoride Circuit Breakers |
| MOQ | 1PCS |
| Customize | Yes |
| Rated Current | 4000A |
| Rated Short-Circuit Breaking Current | 40ka |
| Rated Lightning Impulse Withstand Voltag | Fracture:350+60kv to Eath:350kv |
| Cut Combined Reactor Current | 3150A |
| Transport Package | Wood Box |
| Trademark | HaiRui |
Packaging & Delivery
| Package Size | 1.00cm*1.00cm*1.00cm |
| Package Gross Weight | 1.000kg |
Applications
Suitable for 72.5kV outdoor substations at overhead line terminals, particularly where lightning surge protection is a design priority. The 350kV lightning impulse withstand rating supports insulation coordination for lines entering substations through exposed routes. Buyers should verify the system’s basic insulation level (BIL), surge arrester placement, and protection relay coordination before selecting the breaker.
Frequently Asked Questions
What is the lightning impulse withstand voltage of the LW9-72.5?
The rated lightning impulse withstand voltage is 350kV to earth and 350+60kV across the fracture, providing insulation coordination for 72.5kV systems exposed to lightning surges.
What is the power frequency withstand voltage?
The 1-minute power frequency withstand voltage is 160kV to earth and 160+42kV across the fracture.
What is the rated short-circuit breaking current?
The rated short-circuit breaking current is 40kA, with a peak withstand current of 100kA and a short-time withstand current of 40kA for 3 seconds.
Is the breaker suitable for areas with high lightning activity?
The 350kV lightning impulse withstand rating is designed for overhead line installations where lightning surges are a concern. However, proper surge arrester coordination and grounding design should be verified by the project engineer.
What certification does the product carry?
The breaker is manufactured under ISO9001-2000 quality management standards. Factory test reports and certificates are provided with each unit.
Get a Quote
To request a quotation or discuss customization for the LW9-72.5 SF6 circuit breaker, contact HaiRui with your project specifications including rated voltage, current requirements, fault current levels, installation environment, and quantity needed.






FAQ
What is the lightning impulse withstand voltage of the LW9-72.5?
The rated lightning impulse withstand voltage is 350kV to earth and 350+60kV across the fracture, providing insulation coordination for 72.5kV systems exposed to lightning surges.
What is the power frequency withstand voltage?
The 1-minute power frequency withstand voltage is 160kV to earth and 160+42kV across the fracture.
What is the rated short-circuit breaking current?
The rated short-circuit breaking current is 40kA, with a peak withstand current of 100kA and a short-time withstand current of 40kA for 3 seconds.
Is the breaker suitable for areas with high lightning activity?
The 350kV lightning impulse withstand rating is designed for overhead line installations where lightning surges are a concern. However, proper surge arrester coordination and grounding design should be verified by the project engineer.
What certification does the product carry?
The breaker is manufactured under ISO9001-2000 quality management standards. Factory test reports and certificates are provided with each unit.
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