company news about How to select the appropriate fuse?

When selecting a fuse, several factors must be considered:

1. Dimension appearance:
The size of the fuse selected depends mainly on the space of the circuit and the installation method of the fuse.

2. Safety regulation demonstration:
The choice of fuse for safety certification depends mainly on the region to which the finished product is to be exported, and then the selection of the fuse corresponding to the safety specification is sufficient. For products in North America, American standard fuses (UL248-1&14) are selected. For products in 51 member countries of the CB system such as the European Union, Australia, Japan, South Korea, Singapore, Malaysia, and Brazil, European standard fuses (IEC60127-1/2/3, etc.) are used.

3. Time/current characteristics:
The time/current characteristics, namely the fusing characteristics, are divided into two types: fast break and slow break. The choice of a model depends on the protective effect of the fuse on the circuit. If it is required to withstand both the impact of large pulse currents and the protective effect during overcurrent, a slow breaking fuse should be selected for this situation. If the circuit is sensitive to current pulses, which may damage other components of the circuit, a quick break fuse should be selected.

4. Rated voltage:
The voltage of the circuit must be less than or equal to the rated voltage of the fuse. That is to say, if the voltage of the circuit is 125V, then the selected fuse rated voltage of 125V and 250V can be used. If the circuit voltage is 250V, only 250V fuses can be used, not 125V fuses.

5. Maximum normal working current of the complete machine (IN):
This is the main condition for determining the specification of a fuse. Based on this condition, the specification of the fuse can be preliminarily determined. Considering the differences between actual use and laboratory conditions, the rated current of the selected fuse should be calculated according to the following formula under the operating ambient temperature of 25 ℃: American standard: Rated current of the fuse (IRATED)=IN/0.75 European standard: Rated current of the fuse (IRATED)=IN

6. Ambient temperature:
The rated current of a fuse is tested and confirmed under an ambient temperature of 25 degrees Celsius, and the ambient temperature has a significant impact on the rated current of the fuse. When the ambient temperature is higher than 25 degrees Celsius, the rated current of the fuse will be subject to certain attenuation, and when the ambient temperature is lower than 25 degrees Celsius, the rated current will "increase in value.".