In the use environment of resistance materials, choosing and choosing the right material resistance alloys not only saves costs in production, but also can play the greatest role of resistance alloys. How to choose high-quality resistance alloy wires in our real-life procurement process (Kang Copper wire, manganese copper wire)?
I think that when purchasing resistance alloy wires (constantan wire, manganese copper wire), we need to be certain of some of the conditions we use:
1. Working voltage: (V)
2. Use power: (W)
3. Operating temperature: (℃)
4. Resistivity at 20°C:
5. Wiring mode: star or delta
How to distinguish the selection of constantan wire and manganese copper wire:
1. Operating temperature: Constantan wire has a temperature range of 0-400°C; manganin wire has a temperature range of 5-50°C.
2. Resistivity: the resistivity of constantan wire at 20°C is 0.48±0.03; the resistivity of manganin wire at 20°C is 0.47±0.03.
3. Main components: Constantan wire contains 39%-41% of nickel content, while the manganese content is less than 1%-2%; on the contrary, manganese copper wire contains more manganese, which accounts for 11%-13%. The nickel content is 2%-3%.
4. Price: Since constantan wire contains more nickel, the price is much more expensive than manganese copper wire.
Summary: For the constantan wire and the manganese copper wire, the resistivity of the two is not much different, so it is more economical to use the manganese copper wire when the temperature is not very high.
The difference between Constantan, Manganin and New Constantan:
Constantan wire: grade 6J40. The copper-based type of resistance alloy is a resistance alloy with copper and nickel as the main component. It is often used for sampling in current measurement and plays an important role in the stability of current. Now the domestic constantan wire temperature technology is very mature, and the temperature coefficient can achieve ±40PPM.
Features: The temperature drift is very small, and it has a wide operating temperature range (below 480 degrees). Strong oxidation resistance and excellent welding performance.
Manganese copper wire: a resistance alloy with copper, manganese and nickel as the main components. Low resistance, high accuracy, low temperature coefficient and good stability.
Features: 1. Positive temperature coefficient 2. Small temperature coefficient 3. Small thermoelectric potential when connected with copper wire
New Constantan: The alloy grade is 6J11, the copper-iron-based alloy, the raw material price is 1/3 of the constantan wire, and the temperature drift is large compared with the constantan. It cannot be soldered and needs to be electroplated with nickel or tin.
How to distinguish constantan wire, manganese copper wire and new Kangtai:
The white color is constantan, the copper color is manganin, and the new constantan is also white, which is much lighter than constantan and manganese.
We suggest that buyers need to pay attention to three aspects when purchasing:
1. For sampling, it is best to use constantan wire
2. For shunting, manganese copper wire must be used
3. Constantan wire has strong oxidation resistance and is easy to store. The oxidation resistance of manganese-copper wire is slightly poor, and the time of purchase and storage is not easy to be too long.
