Basic knowledge of Fuse Blade Contact

In many electronic devices, fuses are indispensable protection components. Since Edison invented the first plug-type fuse in the 1890s, the types and applications of copper contactors have continued to expand. The ratings and performance indicators of fuses are usually measured based on laboratory conditions and acceptance specifications. The main international certification systems include UL in the United States, CSA in Canada, MTTI in Japan, and IEC standards of the International Electrotechnical Commission.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The correct selection of Copper Knife depends on a comprehensive evaluation of several factors: Normal operating current: Derating due to ambient temperature should be considered. For example, in an environment of 25°C, it is recommended that the continuous operating current of the fuse contact should not exceed 75% of its nominal value to prevent accidental blowing.

Operating voltage: The voltage rating of the fuse needs to be no less than the circuit voltage. For high-voltage scenarios, such as electric vehicle applications, the voltage level selection of EV fuse copper contacts is particularly important. Breaking capacity and abnormal current: It is necessary to clarify the size and duration of the fault current that needs to be disconnected. The copper blade of the fast-acting fuse must have sufficient breaking capacity to safely cut off the large short-circuit current without bursting.

Environment and pulse conditions: Ambient temperature directly affects current-carrying capacity and life. At the same time, the pulse current (I²t value) existing in the circuit such as surge and start-up is the key to selection. It is necessary to ensure that the melting heat energy I²t value of the fuse is greater than the pulse energy. Structural and installation requirements: Installation space and connection methods need to be considered. Different forms of fuse terminals, such as cylindrical contact blades or Blade Contact, correspond to different mounting clamps and structural dimensions.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cold Resistance: Although negligible in most circuits, the resistance of small current-rated (<1A) fuses can reach several ohms and needs to be evaluated in low voltage applications, especially those with brass/copper contacts. Fusing characteristics: According to the response speed to overload, it can be divided into multiple types such as fast breaking, slow breaking, time delay, etc. The selection of blade fuse contacts needs to match the impact resistance characteristics of the circuit. Thermal energy of melting (I²t): represents the energy required for fusing and is a key parameter to measure the ability to withstand pulse current. When selecting, you must ensure that the pulse I²t value in the circuit is less than 20% of the nominal value of the fuse to ensure reliability.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

High-quality fuse components, such as fuse copper components manufactured using a hot forging process, have higher mechanical strength and current-carrying consistency. When welding and assembling, attention should be paid to controlling the heat to avoid overheating, causing the solder inside the fuse blade contact point to reflow, thus changing its electrical characteristics.

 

 

We focus on the manufacturing of high-precision, high-conductivity circuit protection components, especially Fuse Blade Contact solutions for new energy vehicles and industrial fields. Our products can meet stringent electrical standards. If you are looking for a reliable Blade Fuse Terminal or a customized Fuse Terminal, please contact us for detailed technical support and a product catalog.