Large-current and voltage monitoring device and method

A large-current and voltage monitoring device disclosed by the present invention comprises an upper cover and a lower cover, the upper cover and the lower cover define a cavity, and a shunt is arranged outside the cavity. A monitoring circuit board is arranged inside the cavity, the shunt and the monitoring circuit board are connected electrically via the metal conducting wires, a thermistor is arranged on the surface of the shunt and is connected with the monitoring circuit board electrically, and the monitoring circuit board is connected with a chip electrically. A method of using the device to test comprises the steps of using the shunt to obtain a voltage signal; using the thermistor to obtain a temperature signal of the shunt real-timely; using a single-chip microcomputer to receive, filter and amplify the voltage signal transmitted by the shunt and the temperature signal transmitted by the thermistor; outputting the signals to the chip via a CAN bus transceiver; obtaining the relation of the resistance