Application environment of drop-out fuse cutout:

The 10kV drop-out fuse cutout is suitable for outdoor places where the ambient air has no conductive dust, no corrosive gas, flammable, explosive and other dangerous environments, and the annual temperature difference ratio is within ±40℃. The selection is based on the two parameters of rated voltage and rated current, that is, the rated voltage of the fuse must match the rated voltage of the protected equipment (line).

Environmental conditions for the use of drop-out fuse cutout:

1. The normal operating conditions of the product: the ambient temperature is not higher than +40 degrees and not lower than -40 degrees; the altitude does not exceed 1000m; the maximum wind speed does not exceed 35m/s; the earthquake intensity does not exceed 8 degrees.

2. The product is not suitable for the following places: places with burning or explosion hazards; places with severe vibration or impact; areas with conductive, chemical gas effects and severely polluted salt spray.

Installation points of drop-out fuse cutout:

(1) The melt should be tightened during installation (make the melt subject to a pulling force of about 24.5N), otherwise it is easy to cause contact hair heat.

(2) The fuse should be installed firmly and reliably on the cross arm (frame), and there should be no shaking or shaking.

(3) The fusion tube should have an inclination angle of 25°±2° downward, so that the fusion tube can quickly fall under its own weight when the melt is fused.

(4) The fuse should be installed on a cross arm (frame) with a vertical distance of not less than 4m from the ground. If it is installed above the distribution transformer, it should maintain a horizontal distance of 0.5m or more from the outermost contour boundary of the distribution transformer to prevent In case the molten tube falls and causes other accidents.

(5) The length of the fusion tube should be adjusted appropriately, and the duckbill tongue is required to hold more than two-thirds of the length of the contact after closing, so as to avoid the misoperation of self-falling during operation, and the fusion tube should not top the duckbill. , To prevent the fuse tube from falling down in time after the melt is blown.

(6) The melt used must be a standard product of a regular manufacturer and have a certain mechanical strength. Generally, the melt is required to withstand a pulling force of at least 147N.

(7) The 10kV drop-out fuse is installed outdoors, and the distance between phases must be greater than 70cm.

Points for attention when using drop-out fuse cutout:

Under normal circumstances, it is not allowed to operate the drop-out fuse with load, and only allow it to operate no-load equipment (line). However, branch lines of 10kV distribution lines in rural power grids and distribution transformers with rated capacity less than 200kVA are allowed to operate with load according to the following requirements:

(1) The operation is carried out by two persons (one person for supervision, one person for operation), but must wear insulated gloves that have passed the test, wear insulated boots, goggles, and use qualified insulated rods with matching voltage levels to operate. Operation is prohibited under heavy rain.

(2) When opening the gate, it is generally stipulated that the middle phase should be pulled off first, then the leeward side phase, and finally the windward side phase. This is because the distribution transformer is changed from three-phase operation to two-phase operation, and the arc spark generated when the middle phase is broken is the smallest, which will not cause a short circuit between phases. The second is to pull off the leeward side phase. Because the middle phase has been pulled apart, the distance between the leeward side and the windward side has doubled. Even if an overvoltage is generated, the possibility of a short circuit between the phases is very small. When the windward side phase is finally pulled off, only the capacitive current to the ground is generated, and the spark produced is already very slight.

(3) When closing, the operating sequence is reversed when opening the brake, first close the windward side phase, then close the leeward side phase, and finally close the middle phase.

(4) The operation of the fusion tube is a frequent item. If it is not noticed, it will cause contact burns and poor contact. The contacts will overheat and the spring will be annealed. This will make the contacts worse and form a vicious circle. Therefore, you must use moderate force when pulling and joining the fusion tube. After closing, carefully check that the duckbill tongue can tightly clasp the tongue for more than two-thirds of the length of the tongue. You can hook the upper duckbill with the pull lever and press it down a few times. Try to pull it again to check if it fits well. Failure to be in place or not securely closed when closing, and the static contact pressure on the fuse is insufficient, which can easily cause contact burns or the fuse tube to fall by itself.