The methods to improve the accuracy of resistance measurement by voltammetry are: 1, adding wires to reduce the influence of wire resistance on the measured value; 2, reducing the contact resistance; 3. Adopt high-precision instruments; 4. Use as high a voltage or current as possible.

The function of sliding resistance is to adjust the voltage and current in the line (draw a series variable resistance circuit and a parallel variable resistance circuit, which is used to adjust the voltage in parallel and the current in series).