Claire
Mr.Fu
Claire
High Voltage Air Load Breaker Fuse Switch FK(R)N12-12 for 12kV Systems | China Suppliers & Factory
Type & Meaning
| 1 | Rated short-time withstand current (kA) |
| 2 | Rated current (A) |
| 3 | Spring mechanism |
| 4 | Earthing switch (optional) |
| 5 | Rated voltage (kV) |
| 6 | Design No. |
| 7 | Indoor |
| 8 | Air medium |
| 9 | Load switch |
| 1 | Rated short-circuit breaking current (kA) |
| 2 | Rated current of the maximum fuse equipped (A) |
| 3 | Spring mechanism |
| 4 | Earthing switch (optional) |
| 5 | Rated voltage (kV) |
| 6 | Design No. |
| 7 | Indoor |
| 8 | With fuse holder |
| 9 | Air medium |
| 10 | Load switch |
Ambient Conditions
1) Ambient temperature: within -25℃~+40℃;
2) Altitude: ≤ 2000m;
3) Ambient humidity: daily mean relative humidity ≤ 95% and monthly mean ≤ 90%;
4) Seismic intensity: ≤ Ms8;
5) Anti-fouling level: Class Ⅱ;
6) The operation site should be free of flammable or explosive danger, no water vapor or chemical corrosive gas, no violent vibration.
Note: Please negotiate with the manufacturer if beyond the above-mentioned environmental conditions.
Product Display
Technical Parameters
Technical parameters of FKN12-12D series switch and FKRN12-12D series switch-fuse combinations are shown in Table 1
| No. | Item | Unit | FKN12-12D | FKRN12-12D | ||
| 1 | Rated voltage | kV | 12 | 12 | ||
| 2 | Rated frequency | Hz | 50 | 50 | ||
| 3 | Rated current | A | 630 | 125 | ||
| 4 | Rated insulation level | 1min power-frequency withstand voltage | To-ground, phase-to-phase | kV | 42 | 42 |
| Isolating distance | 48 | 48 | ||||
| Lightning impulse withstand voltage (peak) | To-ground, phase-to-phase | 75 | 75 | |||
| Isolating distance | 85 | 85 | ||||
| 5 | Rated short-time withstand current (kA) | Load switch | kA | 25 | ||
| Earthing switch | 20 | |||||
| 6 | Rated short-circuit duration (short-time withstand time) | Load switch | S | 4 | ||
| Earthing switch | 2 | |||||
| 7 | Rated short-circuit making current (peak) | 50 | ||||
| 8 | Rated breaking current | Active load breaking current | A | 630 | ||
| Closed loop breaking current | 630 | |||||
| Cable charging current | 10 | |||||
| Breaking capacity of no-load transformer | kVA | 1250 | ||||
| 9 | Rated short-circuit breaking current (current-limit fuse) | kA | 31.5 | |||
| 10 | Rated transfer current | A | 1200 | |||
| 11 | Mechanical endurance | time | 2000 | 2000 | ||
Mechanical properties are shown in Table 2
| No. | Item | Unit | Parameter |
| 1 | Isolating distance | mm | ≥175 |
| 2 | Phase-to-phase central distance | 210±2 | |
| 3 | Phase-to-phase air clearance | ≥125 | |
| 4 | Travel | 210±4 | |
| 5 | Overtravel | ≥40 | |
| 6 | Out of simultaneity of three-phase closing | ms | ≤10 |
| 7 | Out of simultaneity of three-phase opening | ≤15 | |
| 8 | Inherent opening time of shunt release | 40~65 | |
| 9 | Main circuit resistance | μΩ | ≤130 |
For the current-limiting fuse in the switch-fuse combinations, the rated current of the fuse-link is selected based on the transformer capacity, and the reference parameters for selection are shown in Table 3
| Transformer capacity (kVA) | 100 | 125 | 160 | 200 | 250 | 315 | 400 | 500 | 630 | 750/800 | 1000 | 1250 |
| Rated current of fuse (A) | 10 | 12.5 | 16 | 20 | 25 | 31.5 | 40 | 50 | 63 | 80 | 100 | 125 |
Outline and Installation Dimension
Frequently Asked Questions
Q1: What is the rated voltage of the FKN12-12D and FKRN12-12D series?
Both the FKN12-12D load switch and the FKRN12-12D switch-fuse combination are rated at 12 kV, making them suitable for medium-voltage indoor distribution systems.
Q2: What is the difference between FKN12-12D and FKRN12-12D?
The FKN12-12D is a standard air-insulated indoor load switch with a rated current of 630A, while the FKRN12-12D is a switch-fuse combination equipped with a fuse holder, rated at 125A, and is used for transformer protection circuits.
Q3: What are the ambient temperature and altitude requirements for installation?
The switch should be installed in environments with ambient temperatures between -25℃ and +40℃ and at altitudes not exceeding 2000m. Humidity requirements are a daily mean relative humidity of ≤95% and a monthly mean of ≤90%.
Q4: How is the rated current of the fuse selected for the FKRN12-12D switch-fuse combination?
The fuse-link rated current is selected based on the transformer capacity. For example, a 100 kVA transformer uses a 10A fuse, a 630 kVA transformer uses a 63A fuse, and a 1250 kVA transformer uses a 125A fuse. Refer to Table 3 for the complete selection guide.
Q5: What is the mechanical endurance of these switches?
Both the FKN12-12D and FKRN12-12D series are designed for a mechanical endurance of 2000 operations, ensuring long-term reliability in demanding switching applications.
Q6: Can these switches be used in environments with corrosive gases or explosive materials?
No. The operation site must be free of flammable or explosive hazards, chemical corrosive gases, and water vapor. For special environmental conditions beyond the standard specifications, users should consult with the manufacturer for customized solutions.