company news about Temperature rise and power consumption of fast fuse

        Power consumption of fast fuse W= Δ UIw； Δ U=f (Iw), where: Iw --- working current; Δ U -- voltage drop of fast fuse.

        The power consumption of the fast fuse has a great relationship with the cold resistance. Selecting a fast fuse with a small cold resistance is beneficial to reducing the temperature rise. The current capacity is mainly limited by the temperature rise. As mentioned earlier, the connection condition of the quick fuse connector also affects the temperature rise of the quick fuse. It is required that the temperature rise of the quick fuse connector should not affect the operation of its adjacent components. The experiment shows that the fast fuse can operate for a long time when the temperature rise is lower than 80 Degree, and the products with stable manufacturing process can still operate for a long time when the temperature rise is 100 Degree. The temperature rise of 120 Degree is the critical point of current capacity. If the temperature rise reaches 140 Degree, the fast fuse cannot operate for a long time.

        At present, the chemical industry generally uses water-cooled busbar and air cooling to reduce the temperature rise of fast fuse. Water-cooled busbar is more effective for low-voltage fast fuse, such as 400-600V. The temperature difference between the quick fuse terminal and the connection end of the water-cooled busbar is generally 1.0~2.0 Degree. Many high-power fast fuses are designed according to water cooling conditions. Users should consult the manufacturer before use. Air cooling is also an effective method to reduce the temperature rise. The wind speed capacity curve determines the impact of wind speed on the temperature rise of the quick fuse. When the wind speed is about 5m/s, it can generally improve the flow capacity by 25%. If the wind speed increases again, it will have no obvious effect.

        The manufacturer provides the voltage drop curve of the fast fuse and the power consumption under the rated current. Measuring the voltage drop between the two terminals of the fast fuse can quickly calculate the actual current of the branch.

        In addition, under the same current condition, the temperature rise is also related to whether the quick fuse adopts single or double connection. High-power rectifier devices manufactured in advanced industrial countries mostly use fast fuses in series with semiconductor devices, such as 700A × 2、1400A × 2、2500A × 2. Double-parallel structure quick fuse terminal can be thinned as far as possible to reduce resistance. One type of double-parallel fast fuse is connected by bolts and connecting plates, and the other type is welded by connecting plates (terminals) and two melts (terminals) as an integrated structure, which is relatively advanced. The high voltage fast fuse has a large internal resistance, especially for products above 800V. The shell porcelain sleeve has a certain length and a large surface area, and the heat generated by the melt is transmitted and dissipated through the filler and shell. Therefore, the high voltage fast fuse has a remarkable air cooling effect.