Current-limiting fuse suppliers teach you to understand Current Limiting Fuse in ten minutes

What is current limiting fuse? 
Current-limiting fuse suppliers tell you that fuses can safely interrupt all possible currents within their rated current and current limit. It limits the fusing time at rated voltage to be equal to or less than the period of the first main or symmetrical current wave, while limiting the passing current to less than the peak current. 

How to install current limiting fuse?
The installation and use environment of the fuse not only affects the performance of the fuse, but also affects the ability to safely break the fault, so it must be considered. A common installation method is to install the fuse in a three-phase closed box. At this time, the rated current of the fuse must be reduced by 15%. However, when the rated current of the fuse is less than 20A, derating may not be considered. This is because the fuse with small rated current itself generates less heat, the temperature rise is low, and the closed environment has little effect on it. Another installation method is to enclose a single fuse in an insulating resin cast. In this case, the rated current of the fuse should be reduced by 25% to ensure that the fuse is not overheated and damaged. For the rated current Fuse below 20A can still ignore derating. 

What is the main function of current limiting fuse
(1) Protection of wires and cables High-voltage current-limiting fuses are used as short-circuit protection for wires and cables. At this time, the rated current of the fuse must match the continuous carrying capacity of the cross-sectional area of ​​the cable used. 
(2) Protect the transformer This is the most commonly used case of high-voltage current-limiting fuses. The fuse manufacturer stipulates the matching table of the rated current of the fuse and the capacity of the transformer. 
(3) Protective capacitor When protecting capacitors in compensation equipment, consider short-circuit transient currents during operation. The magnitude of the inrush current is related to many factors, such as the capacitor capacity, the natural frequency and inductance of the power grid, and the time of input. 
(4) Protect the motor High-voltage current-limiting fuses can also be used to protect the motor, and the lower limit of the protection depends on the starting current of the respective motor. In addition, when selecting fuses. The starting duration and starting frequency are also closely related to avoid fuse breaking due to heat generation.