The rated voltage of the electric vehicle fuse shall be greater than the maximum voltage of the electric vehicle power battery. The selection of electric vehicle fuse is mainly to select the rated current, and the model is determined by the rated current. When designing the high-voltage electrical schematic diagram, it is necessary to determine the insurance specifications required by the corresponding loads one by one according to different loads. Normally, the use of fuse will be derated. It cannot be said that the rated load current is 20A, so you can choose 20A for insurance.
The selection of insurance needs to pay attention to several coefficients, which also become derating coefficients:
1 Temperature coefficient
The temperature coefficient is determined according to the service environment of the fuse. Generally, the service environment temperature of electric vehicles will not exceed 60 degrees. The temperature coefficient can be taken as Kt=0.8
2 Connection coefficient
The connection mode between the fuse and the harness determines the percentage of the connection area in the energized sectional area of the conductor. The larger the contact area is, the closer the coefficient is to 1. The connection coefficient of the fuse connected by the copper lock bolt is Ke=0.8
3 Air cooling coefficient
The air cooling coefficient of electric vehicles is usually taken as: Kv=1
4 Altitude coefficient
At the altitude of electric vehicle below 4000m, the coefficient is Ka=1
5 Sealing factor
Under the requirements of electric vehicle IP67, the sealing coefficient is Kx=0.8
By multiplying the above factors, K=0.512, so the normal load of electric vehicle can be divided by the working current by the derating factor to select the appropriate fuse rated current.
Contact Person: Mr. CK Loh
Tel: +86 188 139 15908
Fax: 86--755-28397356
