The purchase of electric fuse

What should I pay attention to when buying a electric fuse? Today we will briefly understand what to pay attention to when buying a electric fuse and how to choose the right electric fuse.

Element

Before buying a electric fuse, let's first understand the components of the electric fuse. They are: the melt part, which is the core of the electric fuse ; the electrode part, usually two, is an important part of the melt in the circuit; the last one is the bracket part. The whole of the electric fuse is generally slender and soft, and the function of the bracket is to fix the melt, so that the three parts become a rigid whole, which is easy to install and use.

purchase

1. Safety certification: Choose one that meets the electric fuse safety certification, such as UL or IEC specifications.
2. Structure size: Determine the size of the electric fuse according to the space in the circuit design, such as length, diameter, and whether there are leads.
3. Rated voltage: must be greater than or equal to the actual application voltage, generally 24V, 32V, 63V, 125V, 250V, etc.
4. Breaking capacity: should be greater than the maximum fault current in the circuit.
5. Rated current: Refer to the following items:
    (1) Normal working current, 25℃ operation; UL specification electric fuse rated current ≥ normal working current/0.75; IEC specification electric fuse rated current ≥ normal working current/0.9.
    (2) Ambient temperature: The current carrying capacity test of the electric fuse is carried out at an ambient temperature of 25°C. The higher the ambient temperature, the shorter the life of the electric fuse and the lower the carrying capacity. Therefore, the ambient temperature should be considered when selecting the electric fuse .
    (3) Pulse: Pulse will generate thermal cycles, produce mechanical fatigue, and affect the life of the electric fuse. The pulse I2T should be designed to be smaller than the nominal melting heat I2T of the electric fuse under the premise of considering the pulse factor, and the rated I2T of the fuse>actual pulse I2T/Pf (Pf: pulse factor, with the number of pulses that can be withstood)

6. Test: The samples selected through the above procedures need to be tested in the actual circuit to verify whether the selected electric electric fuse is suitable. This verification should include tests under normal conditions and fault conditions to ensure that the selected electric fuse plays a protective role in the protected circuit.
The above is what we need to pay attention to when buying electric fuse at Sophie Electronics. If you don't know anything during the purchase process, you can contact us directly, you only need to explain some parameters, and we will find the most suitable model.