In fact, it is just to install a fast 250mA fuse in the multimeter ..... so that once the current is too large, the fuse will be blown immediately to avoid the multimeter being burned out.

Pointer multimeter is a multifunctional and multi-range measuring instrument. General multimeter can measure DC current, DC voltage, AC current, AC voltage, resistance and audio level, and some can also measure some parameters of capacitance, inductance and semiconductor (such as β).