This article will introduce the definition, classification, material selection, and comparison of copper-manganese wire resistors and copper-nickel wire resistors.

Sampling resistors are components used for current and voltage sampling in circuits and are generally divided into plug-in resistors and chip resistors. Current sampling requires a resistor with a small resistance value in series, while voltage sampling requires a resistor with a larger resistance value in parallel.

The classification of sampling resistors depends on the specific requirements of the circuit board. Under the requirement of resistance accuracy within ±1%, sampling resistors with low resistance values and high precision are sometimes used, and 0.01% precision resistors are used. Most of the sampling resistors produced by domestic factories are plug-in resistors made of copper and manganese copper, but to meet the automation needs of small-scale product production, users need high-precision chip resistors to achieve sampling functions.

Copper-manganese wire resistors are high-precision alloy wires processed by special processes, with low resistance values, high accuracy, low temperature coefficients, no inductance, high overload capacity, and other excellent electrical characteristics. Therefore, copper-manganese wire resistors are widely used in communication systems, electronic equipment, and automatic control power circuits for current limiting, current equalization, or sampling detection circuit connections. Copper-manganese wire resistors have a lower resistance temperature coefficient, a wider range of use temperature (below 500℃), good processing performance, and good welding performance. However, due to the high nickel content of copper, when using ordinary soldering flux during tin soldering, copper is not as easy to weld as manganese copper.

Like copper-manganese wire resistors, copper-nickel wire resistors are made of precision alloy wires processed by special processes, with low resistance values, high accuracy, low temperature coefficients, good stability, no inductance, high overload capacity, and other excellent electrical characteristics. Copper-nickel wire resistors are also widely used in communication systems, electronic equipment, and automatic control power circuits for current limiting, current equalization, or sampling detection circuit connections. The resistance range of copper-nickel wire resistors is 2 milliohms to 1 ohm, and the power range is 1 watt to 10 watts. The accuracy can be selected as 1% or 5%. The stability of copper-nickel wire resistors is better and more suitable for use as sampling resistors.

In summary, there is no essential difference in the performance and uses of copper-manganese wire resistors and copper-nickel wire resistors, but the stability of copper-nickel wire resistors is better and more suitable for use as sampling resistors. The resistance temperature coefficient of copper-manganese wire resistors is more than four times that of copper-nickel wire resistors, and the thermal electromotive force of copper is 20-40 times larger than that of copper-nickel wire resistors. Both can be used to manufacture precision resistors, but the precision level of copper-nickel wire resistors is higher, while copper-manganese wire resistors are more suitable for manufacturing high-power resistors with a certain accuracy.

We hope this article will help you choose the right sampling resistor for yourself.