Do drop-out fuses need to be tested?

Drop-out fuse does not need to be tested, but the size of the fuse should be determined according to the actual load, and the manufacturer's product approved by the power department should be selected. For safety reasons, European-style cable joints should not be too large. Choose the nearest gear above the rated load. Less than or equal to the maximum rated current of the power sector H.

To be on the safe side, check the safety regulations or shipping regulations.

How to select the drop-out fuse

According to the voltage level and capacity of the distribution transformer, the rated voltage of the fuse RW7-10/100A should be greater than or equal to the highest voltage in actual work. The three-phase short-circuit capacity of the distribution transformer must be less than the upper limit of the rated breaking capacity of the drop-out fuse, but must be greater than the lower limit of the rated breaking capacity. High-voltage drop-out fuses are generally suitable for outdoor places where there is no conductive dust, corrosive gas, flammable, explosive and other dangerous substances in the surrounding air, and the annual temperature changes to not more than 40 degrees Celsius and not less than minus 30 degrees Celsius. All parts of the drop-out fuse should be complete, the rotating shaft should be smooth and flexible, the castings should be free of cracks, sand holes and rust, and the porcelain body should be good. Bend phenomenon.

Installation of drop-out fuse:

The installation position of the fuse should meet the requirements, and it should be installed on an iron cross arm (frame) with a vertical distance of no less than 2.5 meters from the ground. If it is installed above the distribution transformer, it should be kept at least 0.5 meters from the outermost contour boundary of the distribution transformer. The horizontal distance is as high as possible, just in case the molten pipe falls down and causes other accidents. When the 10kV drop-out fuse is installed outdoors, the phase-to-phase distance shall not be less than 0.7 meters, and when installed indoors, it shall not be less than 0.5 meters.

The drop-out fuse should be installed firmly (the melt can withstand a pulling force of about 24.5 Newtons), the European-style cable connectors are arranged neatly, and the height is the same. The vertical angle between the axis of the fuse tube and the ground should be 15 degrees to 30 degrees. The operation is flexible and reliable, and the contact is tight. The contact knife-shaped contact RTOHDLRT0-600 600A on the fuse tube should have a certain compression stroke. Misoperation of spontaneous falling occurs during operation, but the fusion tube must not be dead on the duckbill to prevent the fusion tube from falling down in time after the melt is melted. The upper and lower leads should be pressed tightly, and the connection with the circuit wires should be tight and reliable.