Manganin is copper and manganese as the main component of the resistance alloy. Depending on the components to get a different performance, precision manganin and manganin shunt. Because of temperature coefficient of resistance is small, a small copper thermal emf, long-term stability, and therefore suitable for standard resistors, high-grade measuring instruments and shunt resistor. Manganese copper resistance temperature curve of parabola, temperature coefficient of resistance in the vicinity of room temperature is very small, but there is a greater temperature deviation, the resistance also vary widely, with the deviation from the temperature, so that the measuring instruments produced large error, so their optimal operating temperature is: Precision manganin 5 ~ 45 ℃, manganese, copper shunt 10 ~ 80 ℃.