Product Overview
The LW3-12 series outdoor high-voltage sulfur hexafluoride (SF6) circuit breakers are engineered for reliable operation in 12kV power distribution systems. Designed specifically for outdoor use, they utilize SF6 gas as both the arc-extinguishing and insulating medium, ensuring high performance with minimal maintenance. Featuring a compact modular design, the LW3 series delivers superior arc-quenching capability, excellent dielectric strength and low operational effort; its robust construction ensures an extended service life, reduced fire hazard and a smaller installation footprint compared to conventional 10kV outdoor breakers, significantly enhancing system safety and reliability in demanding environments.
Product Display
Model Designation
Model format: LW3-12 I/II/III 400/630 – 6.3/8/12.5/16
- L: Uses SF6 Gas as the Arc-Extinguishing and Insulating Medium
- W: Outdoor Type, Suitable for Outdoor Installations
- 3: Series Design Number
- 12: Rated Voltage (kV)
- I / II / III: Operating Mechanism – I Manual Spring, II Motorized Spring (AC), III Magnetic (DC)
- 400 / 630: Rated Current (A)
- 6.3 / 8 / 12.5 / 16: Rated Short-Circuit Breaking Current (kA)
Service Conditions
- Ambient temperature range: -30 degC to +40 degC
- Altitude:
- Installation environment: Outdoor, standard atmospheric conditions per IEC 60265-1 and GB 3804-1990
Construction
The breaker’s pole unit contains sealed SF6 gas chambers housing fixed and moving contacts; terminal markings follow standard conventions with primary terminals labeled P1 and P2 and secondary current transformer terminals marked S1 and S2 where applicable. All units are factory-filled, hermetically sealed and rigorously tested per IEC 60265-1 (1988) and GB 3804-1990.
The enclosure is constructed from 304L stainless steel for exceptional corrosion resistance in harsh outdoor conditions, giving a compact modular breaker with low operational effort and a reduced installation footprint.
Technical Data
| Parameter | Value |
|---|---|
| Rated voltage | 12 kV |
| Rated frequency | 50 Hz |
| Rated current | 400 A / 630 A |
| Rated short-circuit breaking current | 6.3 kA / 8 kA / 12.5 kA / 16 kA |
| Rated short-circuit making current (peak) | 16 kA / 20 kA / 31.5 kA / 40 kA |
| Rated short-time withstand current (3s) | 6.3 kA / 8 kA / 12.5 kA / 16 kA |
| Power frequency withstand voltage (1 min) | 42 kV (between phases and earth); 48 kV (across open contacts) |
| Lightning impulse withstand voltage | 75 kV (between phases and earth); 85 kV (across open contacts) |
| Mechanical endurance | >=3000 operations |
| SF6 gas pressure (at 20 degC, gauge) | 0.04 MPa |
Standards
The LW3-12 complies with IEC 60265-1 (1988) and GB 3804-1990 for high-voltage switches; performance values meet these requirements for 12kV outdoor applications and factory test reports are provided upon request.
Installation & Dimensions
Installation Diagram
The LW3-12 SF6 circuit breaker features a standardized mounting footprint for easy integration into existing 12kV outdoor switchgear structures. Ensure adequate clearance for safe operation and maintenance access.
| Dimension | Value (mm) |
|---|---|
| Total height | 1850 |
| Width (per pole) | 320 |
| Depth | 580 |
| Pole center distance | 340 |
| Mounting hole pattern | 200 x 200 |
| Primary terminal height | 1650 |