How to avoid the failure of fuse cutout?

It’s important to purchase qualified products.

The capacity of the configured fuse should be selected according to the relevant regulations:

1. The primary side fuse of the transformer is used as the backup protection for the transformer itself and the secondary side outgoing fault. It is matched with the action time of the outgoing switch relay protection of the substation and must be less than the breaking time of the outlet circuit breaker of the substation. The fuse is blown and the outlet circuit breaker does not operate. The transformer capacity is 100kV. Below A, the primary side fuse can be selected at 2 to 3 times the rated current; at 100kV. For distribution transformers of A and above, the primary fuse can be selected at 1.5 to 2 times the rated current.

2. The main fuse of the branch line is mainly used as overload protection. Generally, the rated current of the fuse is selected according to the maximum load current of the branch line. The fusing time should be less than the setting time of the current protection device of the outlet switch of the substation.

3. We can stablish an operating and maintenance account and system for fuse cutout. We should  replace the fuse cutouts which have been in operation for more than 5 years.

4. Improving the technical quality and maintenancing technology of electricians. When installing or replacing the fuse, it must be properly stressed to avoid too loose or too tight.

5. For the uneven casting defects at both ends of the fuse tube, the manufacturer should “chamfer” or make other improvements.