GRL 11kV fuse cutout high voltage suppliers excellent fuse
42×37×13.5cm

Overview of drop out fuse cutout

What is a drop out fuse cutout?

A drop-out fuse cutout is an outdoor high-voltage protective device used primarily on the high-voltage side of distribution transformers or branch lines. It serves to short-circuit and overload protection and load current switching for transformers and lines.

The fuse cutout consists of an insulating base, a fixed contact, a moving contact, and a fuse tube.

How do drop out fuse cutout work?

Drop out fuse cutouts operate with the fuse tube in a closed position maintained by the tension of the fuse wire.

When a fault occurs, the fault current rapidly melts the fuse wire, forming an electric arc. The arc-extinguishing tube heats up and releases gas, creating high pressure inside the tube, which forces the arc to elongate and extinguish rapidly.

Upon melting, the fuse wire releases tension, causing the lower moving contact to flip down and the fuse tube to drop, creating a visible open position.

For load disconnection, an insulated rod pulls the moving contact, which separates the auxiliary contact, generating an arc that is extinguished as the current reaches zero.

Selling points of drop out fuse cutout

1、High Mechanical Intensity and Reliable Structure: Ensures safe operation of the line.

2、Good Pollution Resistance: Requires minimal maintenance in polluted areas.

3、Acid and Alkalis Resistance: Offers excellent heat-proof aging and electrical resistance.

4、Good Brittle Resistance: Strong earthquake resistance to avoid fracture accidents.

5、Easy Installation: Large diameter ring pull design for convenient installation and operation.

Technical information of drop out fuse cutout

The application of drop out fuse cutout

1、Protection of Transformers

Transformers are vital for adjusting voltage levels between high-voltage transmission lines and lower-voltage distribution lines. drop-out fuse cutout protect these transformers from currents exceeding their capacity, which can cause overheating and failure.

2、Line Protection

drop-out fuse cutouts safeguard distribution lines from overcurrents caused by faults like line-to-ground contacts or short circuits, ensuring a stable and reliable power supply.

3、Equipment Safety

Beyond transformers and lines, drop-out fuse cutouts are integral to protecting a variety of electrical equipment from overcurrent damage, thus ensuring longevity and reducing maintenance costs.

Precautions for drop out fuse cutout

1、Proper Sizing and Selection: Ensure correct sizing to match the system’s operating current and specific equipment protection needs.

2、Regular Inspections: Periodic checks for wear, damage, or contamination to maintain system integrity.

3、Safe Handling Practices: Only qualified personnel should handle high voltage fuses, using proper safety equipment and procedures.

4、Environmental Considerations: Installations should account for local conditions like temperature extremes and moisture to ensure reliable operation.

Operating conditions of drop out fuse cutout

1、Ambient temperature: -40℃ ~+40℃ ;

2、Relative humidity: the daily average value is not bigger than 95%, and the monthly average value is not bigger than 90%;

3、Installation location: the altitude does not exceed 1000m;

4、Wind speed: no more than 35m/s;

5、Ice coating thickness: no more than 10mm;

6、Installation location: There should be no risk of fire, explosion, chemical corrosion and severe vibration;

7、Earthquake intensity: no more than magnitude 8;

8、Not suitable for places with burning or explosion hazards, places with severe vibration or impact, conductive and chemical gas, and areas with severe pollution and salt spray.