Φ2.4×7, 3×7mm Bussmann series Ceramic Tube Slow Acting Small Fuse
- PRODUCT DETAIL
The fuse at that time was an ordinary glass tube fuse, and it was not very convenient to buy a fuse in the countryside. Sometimes I use the wire directly as a fuse (I believe many people have done this). The TV can also be used normally by connecting the circuit with iron wire, but it is very unsafe to use. Sometimes, other parts of the TV are damaged, and since then I have been impressed with this transparent glass tube fuse.
Fuses define it as a "fuse link" in international standards. It is an electrical component installed in a circuit to ensure the safe operation of the circuit. Electronic products are all-encompassing, and these products that require electricity must be equipped with the same small components and fuses that are responsible for safety. Not only are there fuses on 3C products, fuses must also be installed on ordinary cars or electric cars.
Now as the products become smaller and smaller, they are more and more integrated, and the shape and size of fuses are also very different from traditional fuses. For example, the fuse of the mobile phone must conform to the trend of fast charging. To withstand the instantaneous large current, to achieve its protective function, the requirements of fuses are getting higher and higher.
The glass tube fuses we usually see are not a single material. It is an alloy made of lead, antimony, and tin. This is to achieve the purpose of low melting point and these metals are added, copper caps at both ends, so that the conductivity will be better, the surface of the copper cap is nickel plated.
The chip fuse is composed of a plastic sheet and two metal sheets, which are commonly used in automobiles, and glass tubes are often used in electronic products.
Cylindrical fuses will directly solder the pins at both ends to the circuit board. The square fuse has the characteristics of insulation and space saving, and is often used in electronic products such as computers.
The function of the fuse is that when the circuit malfunctions or is abnormal, the current increases continuously, and the increased current may damage the components, burn the circuit or even cause a fire.
If a fuse is installed in the circuit, when the current abnormally rises to a certain level, the fuse is blown to cut off the current and protect the appliance.
Fuses were born in the 1880s. Edison invented a fuse equivalent to a safety valve in the circuit and applied for a patent. The fuse was invented at the time to protect incandescent lamps, because incandescent lamps were very expensive at the time when they were first invented.
With the development of society and the continuous increase of electrical appliances, the fuse industry has also developed rapidly. The fuse industry in China started relatively late, and it was not until the 1970s that TV sets were localized that they promoted the development of fuses in China.
The working principle of a fuse is that when a current passes through a conductor, the conductor will generate heat due to the resistance of the conductor. After the material and shape of the fuse are determined, its resistance is fixed. When current flows through it, it will heat up, and its heat generation will increase with time. The size of the current and resistance determines the rate of heat generation. The structure of the fuse and its installation condition determine the rate of heat consumption. If the rate of heat generation is less than the rate of heat dissipation, the fuse will not blow.
If the rate of heat generation is equal to the rate of heat dissipation, it will not melt for a long time. If the rate of heat generation is greater than the rate at which heat disappears, the amount of heat generated will increase and the increase in heat will cause the temperature to rise. When the temperature rises above the fuse's melting point, the fuse will blow.
Manufacture of common glass tube fuses. The silicon dioxide material is first drawn into a transparent glass tube with a diameter of 5 mm through high temperature, and then cut into a length of 20 mm. The two ends of the glass tube must be rounded with high temperature to avoid the sharp edges of the glass tube from scratching the fuse when passing through the fuse.
An alloy fuse is placed in the glass tube, and the printed top and bottom covers are welded together with the fuse by high frequency.
Some people may wonder why the common fuse is installed in a glass tube. First, the glass tube is insulated and difficult to ignite, ensuring that the fuse is the only conductive connection intermediary at both ends. The cheap price of glass tube is also the reason to use it. In addition, the glass tube can see whether the internal fuse is blown, it is relatively easy to judge the quality of the fuse, and the glass tube is not vacuum.
With the development of technology, more types of fuses have appeared. Such as the resettable fuse, this type of fuse is automatically deformed when the temperature exceeds a certain safe temperature, leading to power failure. After the temperature is restored, it can be automatically powered on to work normally without manual intervention.
Intentions to develop, to use technology to benefit society
|Breaking Capacity||Material||Operating Temperature||Soldering conditions|
|1500A at 250V AC(1A-10A)||
Fuse body –ceramic tube
End cap--nickel plated brass
Pigtail--tin plated copper on nickel plated brass cap
Hand solder: 360℃,≤1S
|Testing current||Blow Time|
Approvals（○ Pending ● Approvals）
|Current Rating||Voltage Rating||Norminal Melting I2T(A2sec)||Approvals|