The constant copper wire resistance and the manganese copper wire resistance are two common resistances. Due to their characteristics, these two kinds of resistors can be widely used in many fields. If the current sampling circuit and the voltage sampling resistor are more suitable, which one is more suitable? Let's take a closer look at these two resistors!
 
First, the constant copper wire resistance
So, what is the constantan wire resistance? Simply put, the constant copper wire resistance is made of high-precision alloy wire and processed by special process. It has low resistance, high precision, low temperature coefficient, non-inductance and high overload capability. It is precisely because of the excellent electrical characteristics of the above, it is widely used in communication systems, electronic whole machines, automatic control of power supply and other circuits for current limiting, current sharing or sampling and detection circuit connection. 
 
In addition, there is a new constantan resistance alloy, which is a copper-iron-based alloy, which has the same electrical resistivity as the constant copper, a substantially similar temperature coefficient of resistance, and the same operating temperature. Compared with the constantan resistance alloy, new constantan has the advantage of low price because it does not contain high-priced nickel, but its oxidation resistance is worse than that of constantan. In many aspects, it can replace the constantan wire resistance alloy. At the same time, it has also been widely used in the design of regulated power supply. His role in the design of regulated power supply is overcurrent protection and test load current. 

 
Second, manganese copper wire resistance
 
The manganese copper wire resistance is the same as the constant copper wire resistance. The same precision alloy wire is used for special processing, which has low resistance, high precision, low temperature coefficient and good stability. It has no inductance and high overload capability. Manganese copper wire resistance is also widely used in communication systems, electronic whole machines, automatic control of power supply and other circuits for current limiting, current sharing or sampling and detection circuit connection.
 
Which resistor does the sampling resistor choose?
 
There is no essential difference between the performance uses of the two resistors, but if the sampling resistor is more oriented to the manganese copper wire resistance, its stability is better. The temperature coefficient of resistance of Constantan is more than 4 times that of manganese copper; the thermoelectric potential of Constantan to copper is 20-40 times larger than that of manganese copper; in addition, because of the high nickel content of Constantan, during soldering, In the case of ordinary flux, Constantan is not as easy to weld as manganese bronze.