EO has conducted a wide range of life cycle tests on many kinds of electrical devices and wiring equipment.
EO recommended, from the diameter of 0.015 inches (0.38mm) and the following single wire twisted into the conductor, should be silver or nickel-plated copper single line, to prevent copper single surface oxidation. UL found that very thin copper wire is more likely to be damaged by oxidation corrosion.
Choosing nickel as coating material has obvious advantages. In many metallic materials, nickel is considered to be a better resistance to accelerated oxidation in high-temperature environments. Nickel's melting point is also very high (about twice times the copper), so it can be plated conductor for effective high temperature protection. The copper conductor is plated with nickel, but the resistivity is slightly higher, but it is soft and anti-fatigue.
At 250 ℃ temperature, the use of nickel plated copper conductor is very important, nickel coating weight than 2% is enough. When the temperature is 450 ℃ and above, it is recommended to increase the thickness of nickel coating, in the United States, the weight ratio of nickel coating is usually 27%.
Pure nickel conductor should be used when the temperature exceeds 600 ℃, especially when the high and low temperature change continuously.
The carrying capacity of the nickel plated conductor is larger than that of the equal specification copper conductor. If all wire and cable in a pipe, trough, or cable tray transmit the same large current at the same insulating temperature, the outer diameter and space occupied by the nickel plated conductor wire and cable can be significantly reduced. For permissible carrying capacity of nickel-plated copper conductor and copper conductor, refer to NEC procedures.