Drop out fuse

Product introduction

Drop out fuse is the most commonly used short circuit protection switch for branch lines of 10kV distribution lines and distribution transformers. It has the characteristics of economy, convenient operation and strong adaptability to outdoor environment. It is widely used in 10kV distribution lines and the primary side of distribution transformers for protection and equipment switching. It is installed on the branch line of 10kV distribution line, which can reduce the scope of power failure. Because it has an obvious disconnection point of high-voltage drop fuse, it has the function of disconnecting switch, creating a safe working environment for lines and equipment in the maintenance section, and increasing the sense of safety of maintenance personnel.

Working principle

    The moving contacts at both ends of the fuse tube are fastened by the fuse (melt). After the upper moving contact is pushed into the protruding part of the "duck beak", the upper static contact made of phosphor copper sheet is against the upper moving contact, so the fuse tube is firmly stuck in the "duck beak". When the short circuit current is fused through the fuse, an arc is generated. The steel paper tube lined with the fuse tube generates a large amount of gas under the action of the arc. Because the upper end of the fuse tube is sealed, the gas is ejected to the lower end to blow out the arc. As the fuse is blown, the upper and lower moving contacts of the fuse tube lose the binding force of the fuse. Under the action of the gravity of the fuse tube itself and the spring sheets of the upper and lower stationary contacts, the fuse tube drops rapidly, breaking the circuit and cutting off the line or equipment in the fault section.

    The fuse on the actual 10kV line system and the distribution transformer can not operate correctly. One of the reasons is that the electrician's quality is poor, and his sense of responsibility is not strong. He does not carry out the maintenance and overhaul of the drop out fuse all the year round; The second reason is that the product quality of drop out fuse is poor and it cannot be flexibly pulled and closed. Two reasons reduce the function of drop out fuse. In reality, there are often cases of lack of melt pipe, lack of melt, or using copper wire, aluminum wire or even iron wire to hook up to replace the melt. The tripping rate of the line and the fault rate of the distribution transformer remain high.