Use And Maintenance Of Fuses

1. When a fuse blows, the cause of the fuse failure must be carefully analyzed. Possible reasons include:
1) Short circuit fault or overload operation causing normal fuse failure;
2) The fuse has been in use for too long, and its characteristics have changed due to oxidation or high operating temperature, leading to premature failure;
3) Mechanical damage during fuse installation reduces its cross-sectional area, causing premature failure during operation.
2. When replacing a fuse, the following requirements must be met:
1) Before installing a new fuse, the cause of the fuse failure must be determined. Do not replace the fuse and attempt to re-energize the circuit without determining the cause of the failure;
2) When replacing a new fuse, check whether the fuse's rating matches the protected equipment;
3) When replacing a new fuse, check the internal burning condition of the fuse tube. If there is serious burning, the fuse tube should be replaced at the same time. When the porcelain fuse tube is damaged, it is not allowed to replace it with a tube made of other materials. When replacing the fuse in a filled fuse, pay attention to filling the filler material.
3. Maintenance work on fuses drop out fuse should be carried out simultaneously with the power distribution equipment:

1) Clean dust and check the contact points;

2) Check the appearance of the fuse (remove the fuse tube) for damage or deformation, and for any signs of discharge flashing on the ceramic parts;

3) Check whether the fuse and its fuse element are compatible with the protected circuit or equipment. If any problems are found, investigate them promptly;

4) Pay attention to checking the N line in a TN grounding system and the grounding protection line of the equipment. Fuses are not allowed to be used on these lines;
5) When maintaining and inspecting fuses, the power supply must be disconnected according to safety regulations. It is not allowed to remove the fuse tube while it is energized.