| Brand | ROCKWILL |
| Model NO. | 12kV indoor high-voltage load break switch |
| Rated voltage | 12kV |
| Rated normal current | 400A |
| Rated frequency | 50/60Hz |
| Series | FN |
Product Overview
The FN5 - 12 indoor AC high - voltage load break switch (hereinafter referred to as the load break switch) is suitable for AC 50Hz, 12kV networks. It is used for breaking load current and closing short - circuit current. The load break switch with a fuse can cut off short - circuit current and be used as a protection switch.
This load break switch can be equipped with the CS6 - 1 manual operating mechanism and the special CS manual operating mechanism for this product.
Key Features
Precise Current Control：Suitable for 12kV, 50Hz AC systems. It can stably break load current and close short - circuit current, ensuring normal operation and maintenance of the power grid as well as emergency operations during faults.
Extended Protection Function：When paired with a fuse, it can cut off short - circuit current and act as a protection switch, providing overload and short - circuit dual protection for power equipment and simplifying the protection levels of the distribution network.
Wide Scene Adaptability：Focused on indoor 12kV AC networks. It is suitable for typical indoor power distribution scenarios such as ring main units and box - type substations, meeting the needs of distribution network construction.
Flexible Mechanism Configuration：Supports the CS6 - 1 general manual operating mechanism and can also be adapted to the special CS mechanism, compatible with different operating habits and equipment matching requirements.
Mature Technical Architecture：Iterated based on the classic FN5 - 12 model. It has a compact structure, stable arc - extinguishing performance, high long - term operation reliability, and reduces operation and maintenance costs.
Technical Parameters
Name |
Unit |
Value |
Rated Voltage |
kV |
12 |
Maximum Operating Voltage |
kV |
12 |
Rated Frequency |
Hz |
50 |
Name |
Unit |
Value |
|
Rated Current |
A |
400 |
630 |
Rated Short - time Withstand Current (Thermal Stable Current) |
kA/S |
12.5/4 |
20/2 |
Rated Peak Withstand Current (Dynamic Stable Current) |
kA |
31.5 |
50 |
Rated Closed - loop Breaking Current |
A |
400 |
630 |
Rated Active Load Breaking Current |
A |
400 |
630 |
5% Rated Active Load Breaking Current |
A |
20 |
31.5 |
Rated Cable Charging Breaking Current |
A |
10 |
|
Rated No - load Transformer Breaking Current |
No - load Current of 1250kVA Transformer |
||
Rated Short - circuit Making Current |
kA |
31.5 |
50 |
Load Current Breaking Times |
Load/Time |
100%/20 |
30%/75 |
1min Power Frequency Withstand Voltage (Effective Value, to Ground, Phase - to - Phase/Isolation Break) |
kV |
42/48 |
|
Power Frequency Withstand Voltage, Between Isolation Breaks |
kV |
53 |
|
Lightning Impulse Withstand Voltage (Peak Value, to Ground, Phase - to - Phase/Isolation Break) |
kV |
75/85 |
|
Opening and Closing Operating Torque (Force) |
N·m (N) |
90(80) |
100(200) |
Technical Parameters of Fuse
Model |
Rated Voltage (kV) |
Rated Current of Fuse (A) |
Rated Breaking Current (kA) |
Rated Current of Fuse Element (A) |
RN3
|
12
|
50 |
12.5 |
2, 3, 5, 7.5, 12, 15, 20, 30, 40, 50 |
75 |
12.5 |
75 |
||
100 |
12.5 |
100 |
||
200 |
12.5 |
150, 200 |
||
SDL*J |
12 |
40 |
50 |
6.3, 10, 16, 20, 25, 31.5, 40 |
SFL*J |
12 |
100 |
50 |
50, 63, 71, 80, 100 |
SKL*J |
12 |
126 |
50 |
125 |
Operating Environmental Conditions
Altitude: Not exceeding 1000m;
Ambient Air Temperature: Upper limit +40°C, Lower limit -25°C (Not lower than -5°C for motor - operated mechanisms);
Relative Humidity: Daily average not greater than 95%, Monthly average not greater than 90% (+25°C);
Ambient air should be free from obvious pollution by corrosive or flammable gases, water vapor, etc.;
No frequent severe vibration.
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