Overview
OverviewWhat is a drop out fuse cutout?
Drop-out fuse cutout and load-drop out fuses are outdoor high voltage protective devices.They are installed on the high-voltage side of distribution transformers or branch lines of distribution lines, used for short-circuit and overload protection as well as load current switching for transformers and lines.
The fuse cutout consists of an insulating base, a fixed contact, a moving contact, and afuse tube. The fixed contact is installed at both ends of the insulating support,and the moving contact is installed at both ends of the fuse tube. The fuse tube is composed of an inner arc extinguishing tube and an outer layer of phenolic paper tube or epoxy glass cloth tube.
The load-drop-out fuse incorporates a spring-loaded auxiliary contact and an arc-extinguishing hood to enable the switching of load currents.
How do high voltage fuse cutout work?
The high voltage fuse cutout operates normally with the fuse tube closing position formed by the tension of the fuse wire.
When a fault occurs in the system, the fault current rapidly melts the fuse wire, forming an electric arc. The arc-extinguishing tube is heated by the arc, releasing a large amount of gas, which creates high pressure inside the tube and forms a longitudinal blowout along the tube. The electric arc is rapidly elongated and extinguished.
After the fuse wire melts, the lower moving contact loses tension and flips down, releasing the fuse tube from the lock, causing the fuse tube to drop and form a clear open position.When disconnecting the load, the insulated rod is used to pull the moving contact.
At this point,the moving and static contacts are still in contact. Continuing to pull the moving contact with the insulated rod, the auxiliary contact rapidly separates, generating an electric arc between the auxiliary contacts. The electric arc is elongated in the arc extinguishing cover slot, while the arc extinguishing cover generates gas. When the current reaches zero, the electric arc is extinguished.
Selling points
1.High mechanical intensity,reliable stucture,
provides a guarantee for the safe operation of the line.
2、Good pollution resistance performance
Strong anti-pollution ability,wide range of application
it does not require annual cleaning and maintenance in
polluted Areas.
3、Acid and alkalis resistance
heat-proof aging and electricity resistance;
Seal well to ensure internal insulation without damping.
4、Good brittle resistance
Strong earthquake resistance,Avoid fracture accidents
5、Easy to install
Large diameter ring pull design.installation and operation more Convenient
Technical information High-Voltage fuse cutout
The Application of High-Voltage fuse cutout
Protection of Transformers: Transformers are vital for adjusting voltage levels between high-voltage transmission lines and lower-voltage distribution lines. High-voltage fuse cutout protect these transformers from currents exceeding their capacity, which can cause overheating and failure.
Line Protection: High-voltage fuse cutout safeguard distribution lines from overcurrents caused by faults like line-to-ground contacts or short circuits, ensuring a stable and reliable power supply.
Equipment Safety: Beyond transformers and lines, high voltage fuse cutout are integral to protecting a variety of electrical equipment from overcurrent damage, thus ensuring longevity and reducing maintenance costs.
Precautions for HV fuse cutout
Proper Sizing and Selection: fuse cutout must be correctly sized according to the system’s normal operating current and the specific equipment they are protecting. Over or under-sized fuses can lead to unnecessary service interruptions or fail to provide adequate protection.
Regular Inspections: Fuse cutouts should be inspected regularly for signs of wear, damage, or contamination. Inspections help identify issues before they lead to failures, ensuring the system’s integrity.
Safe Handling Practices: Due to the high voltages involved, only qualified personnel should handle fuse cutouts and high-voltage fuses. Proper safety equipment, tools, and procedures must be used to prevent electrical shock or accidents.
Environmental Considerations: The performance of high-voltage fuse cutouts can be affected by environmental conditions, such as temperature extremes and moisture. Installations should account for local environmental factors to ensure reliable operation.
Fuse Normal Operating Conditions
1、Ambient temperature: -40℃ ~+40℃ ;
2、Relative humidity: the daily average value is not biggerthan 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.
Ordering instruction
1、tem No；
2、Rated Voltage;
3、Rated Current;
4、Whether with arc extinguishing chamber;
5、Whether with mounting bracket ;
6、Please inform us with your special requirements.
