What are the precautions for using patch fuse

时间:2019-07-23 丨 预览:196 人次

Matters needing attention in the use of chip fuses:


1. Maintain the current for normal operation of the circuit. When selecting a model, you need to determine the normal current of the circuit to select the corresponding type of chip fuse. The operating current through the fuse should not exceed 75% of the additional current of the fuse.


2. Pulse, surge current, surge current, starting current and circuit transient value. Due to the technical reasons brought by the small size of the chip fuse, the impact resistance of the chip fuse is much smaller than the glass tube fuse or other larger fuse with the same extra current.


3. The size of the overload current of the circuit and the shortest and longest time that the overload current exists. The basic requirements for the fuse can not be broken when the time should not be broken, and the broken time must be broken within the appropriate time.


4. The resistance of the chip fuse has a certain effect on some circuits: if a fuse with an internal resistance that is too large is installed in some circuits, it will affect the number of systems in the circuit, making the circuit unable to operate normally.


5. Operating environment temperature of the fuse: When the chip fuse is used in portable equipment, the temperature rise of the fuse should be properly considered, that is, the reduction of the extra current of the fuse. The ambient temperature during fuse operation should be within the specified operating temperature range. When the ambient temperature around the fuse exceeds 25 ° C, the temperature reduction curve should be used to degrade it.


6. The applied voltage applied to the fuse. Generally, chip fuses are used in portable equipment, and the circuit operating voltage is generally not high. As long as the additional voltage of the chip fuse is higher than the circuit operating voltage, you can safely choose it.


7. Product size. Since chip fuses are generally used in more highly integrated products, it is generally necessary to pay attention to whether the corresponding package can be properly installed on the protected circuit at the time of type selection.


8. Product certification. For example, export to North America, must have UL or CSA certification. Now products exported to Europe also need to comply with the EU ’s RoHs directive, which is generally referred to as SGS and other environmental certifications.