The Difference between Fast Blow Fuse and Slow Blow Fuse

Both types of fuses are double caps; so for the product characteristics and safety performance of the fuse; gG ", that is, a combination of contact caps and contacts; that is, the so-called double cap (inner/outer cover). And Ordinary small or underground processing plants, to cut corners and reduce costs, will use single-cap pressure riveting "single cap and double cap": mainly cylindrical cap-shaped fuses are more common, and the impact on reliability is very large.

"External welding and internal welding": From the point of view of the fuse manufacturing process, this statement should refer to the spot welding process of different types of fuses. In general, these are two common fuses, and there are other types of fuses, such as "aM". From the appearance of the fuse, it can be seen that the solder joints are externally welded, and the solder joints are internal. The solder joints cannot be seen from the outside, which is what you call internal soldering.

There are fast-blow and slow-blow fuses, mainly due to different response times. In essence, the two are different in I2t indicators, and fast-blow fuses are generally used to protect sensitive products from damage. If a slow-blow fuse is selected by mistake, It may cause damage to the equipment and fail to protect the device, so the selection of the fuse depends on the requirements of the protected circuit.

The Performance Difference between Fast Blow Fuse and Slow Blow Fuse

People think that when a fault current is encountered in the circuit, the faster the action of the fuse, the better, and the stronger its protective function. In this sense, the protection performance of the slow-blow fuse is not as good as that of the fast-blow fuse, so is this statement correct? It is true that under the same overcurrent load conditions, the action speed of the slow-blow fuse is slower than that of the fast-blow fuse, but this is not because its response speed is slow, but because it requires more energy to blow, and it can be said that it not only can respond to overcurrent, and also can judge the type of overcurrent or the amount of energy. The delay time during the activation process can be regarded as the time for the slow-blowing fuse to judge the overcurrent.

Generally speaking, over-current can be divided into two categories: surge and fault. Surge overcurrent is mostly caused by charging and discharging during circuit switching or the influence of surrounding circuits. The pulse peak value is large and the duration is short, and the energy released is often not large. Slow blow fuses can withstand such overcurrent shocks without causing a fuse action. The fault overcurrent is continuous. Even if the peak value is not necessarily high, its energy will greatly exceed the surge overcurrent. The slightly slower action speed not only does not affect its protection function, but enhances its protection function, avoids the chance of misoperation, and can be used on a wider range of occasions to protect a variety of circuits. On the contrary, the fast-blowing fuse can make its action blown due to smaller energy. Although the action speed is fast, the reason for this is limited.