High-Capacity NU-FH-12-1250-25 Load Switch for Gas-Insulated Switchgear Systems
Product Description
The NU-FH-12-1250-25 Load Switch is a robust and versatile switching solution engineered specifically for 12kV/1250A gas-insulated switchgear (GIS) and high-voltage ring main units. Designed for effortless installation and long-term mechanical stability, this load break switch (LBS) efficiently manages the power distribution needs of heavy-duty industrial and utility environments. It fully complies with international and domestic safety standards, including GB 3804-2017 and GB 16926-2009, making it a critical core component for AC high-voltage load switch-fuse combination units.
Applications
- Main control and protection switch for 12kV gas-insulated switchgear and modular substations.
- Core component for load switch-fuse combination units in secondary distribution networks.
- Reliable power control for urban grids, renewable energy plants, and large-scale industrial facilities.
Environmental Conditions
- Altitude not exceeding 2000 m; seismic intensity not exceeding 8 degrees;
- Pollution degree: II;
- Ambient temperature range: -40°C to +40°C; relative humidity: daily average not exceeding 90%, monthly average not exceeding 90%;
- Not suitable for installation in locations subject to frequent severe vibration, or where water vapor, gases, chemically corrosive deposits, salt fog, dust, or dirt significantly affect the performance of the mechanism, or where there is a risk of fire or explosion.
Technical Parameters
| No. | Item | Unit | Value |
| 1 | Rated voltage | kV | 12 |
| 2 | Rated current | A | 1250 |
| 3 | Rated short-time withstand current | kA/S | 25/3 |
| 4 | Rated peak withstand current | kA | 50/63 |
| 5 | Rated short-circuit closing current | kA | 50/63 |
| 6 | Rated frequency | HZ | 50 |
| 7 | Theoretical operation | time | 5000 |
Drawing

FAQ for Gas-Insulated Load Break Switches
- Q: Why is the 1250A rating important for this GIS Load Switch?
A: The 1250A rating ensures the switch can handle higher power loads without overheating, providing a significant safety margin for main circuit applications in a gas-insulated switchgear.
- Q: Can this mechanism withstand harsh environmental conditions?
A: Yes. The device is tested for stable performance in temperatures from -40°C to +40°C. For the external cable terminations connected to this switch, consider using our Industrial Cable Clamp for secure fixation.
- Q: Is it compatible with circuit breaker configurations in the same project?
A: Absolutely. For the vacuum protection sections of your GIS project, this switch works seamlessly alongside our GIS Vacuum Circuit Breaker.
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