| Brand | ROCKWILL |
| Model NO. | Indoor high-voltage load break switch with fuse |
| Rated voltage | 6kV |
| Rated normal current | 400A |
| Rated frequency | 50/60Hz |
| Series | FN |
Product Overview
The FN3 - 12, FN3 - 12R, and FN3 - 12R/S load break switches are high - voltage electrical appliances installed indoors. They are suitable for AC 50Hz, 6kV or 10kV networks to break and close load and overload currents. They can also be used as switches for breaking and closing no - load long lines, no - load transformers, and capacitors. The load break switches with RN3 - type fuses (FN3 - 12R, FN3 - 12R/S) can cut off short circuits and be used as protection switches.This load break switch can be operated with CS3 - type and CS2 - type manual operating mechanisms.
Key Features
Multi - scenario Current Control：Suitable for 50Hz, 6kV/10kV AC networks. It can stably break and close load and overload currents, and also support the switching operations of no - load long lines, no - load transformers, and capacitors, covering multiple operation and maintenance scenarios of the distribution network.
Extended Short - circuit Protection：After being equipped with an RN3 - type fuse (such as the FN3 - 12R series), it has the ability to cut off short - circuit currents. It can be used as a protection switch to provide short - circuit fault protection for equipment and lines, simplifying the protection configuration of the distribution network.
Installation Scenario Adaptation：With an indoor installation design and a compact structure, it is suitable for typical indoor power distribution facilities such as ring main units and box - type substations, meeting the construction and renovation needs of indoor power distribution systems in urban distribution networks, industrial and mining enterprises, etc.
Operating Mechanism Compatibility：It supports CS3 and CS2 - type manual operating mechanisms, adapts to different operating habits and existing equipment support systems, reduces the cost of renovation and replacement, and improves the flexibility of on - site operation and maintenance.
Mature Technical Architecture：Iterated based on the classic FN3 series, it has stable arc - extinguishing performance, a long mechanical service life, and high long - term operation reliability, reducing the frequency of equipment failures and operation and maintenance workload.
Technical Parameters
Operating Environmental Conditions
Altitude: Not exceeding 1000 meters;
Ambient air temperature: Not higher than +40°C and not lower than -10°C;
Indoor places with air relative humidity not exceeding 90% (when the temperature is +25°C);
Environments free from conductive dust;
Environments free from corrosive gases that damage metals and insulation;
Places without severe vibration and impact;
Environments without fire and explosion hazards.
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