We often find that in the process of installing and using copper wire cable, there will be a conductor copper wire oxidation discoloration (black) problem. Many people think that copper wire black is poor quality; why black? What causes the blackness? Here are some of the most overlooked causes of blackness.

The main reasons for black copper wire cable

General copper wire cable's copper conductor oxidation discoloration (black) because the product production, transportation, storage, laying, and use processes are wet environments or rain immersed in the cable conductor, so that the copper conductor and oxygen, water, and chemicals react and discolor (black).

The blackened parts and conditions of the copper conductor of the copper wire and cable are also different: the end of the cable conductor is black, or the two ends are intact, and the middle is black.

In short, there are generally three reasons for the oxidation discoloration (black) of the copper conductor of the copper wire: "water, moisture, and air immersion."

Several conditions that cause copper wire blackening

1. Improper sealing of cable joints

The cable connector seal is not packed properly, causing air to invade the copper conductor and cause blackening. When packing the cable head, most of the masters will use insulation tape to directly seal; in fact, the insulation tape is not waterproof and there is a layer of glue on it, which will make the cable black for a long time.

2. The insulation is damp

This situation is very common and usually occurs at the cable junction in the directly buried or row pipe. If the cable joint is not qualified and the joint is made in humid climate conditions, it will make the joint watery or mixed with water vapor, and the cable will become black over time. This phenomenon is more common in hot summers because the humidity in the air is relatively high, and the temperature will accelerate the oxidation reaction of copper conductors.

3. Use is not standard

During the installation process for the customer, cutting the cable does not seal the cable head, or non-standard construction operations lead to oxygen in the water, which will also easily cause the cable to black.

 Severial situation of middle black couple wire

1. Transportation environment

The finished product is bumpy in the transportation process; the cable insulation layer is damaged by extrusion, bumps, scratching, etc. When the local damage place of the cable copper conductor is in contact with oxygen and moisture in the air for a long time, it may be oxidized and discolored (black).

2. Copper rod drawing process

Copper rods are made into various specifications of copper wire through the wire drawing process. For large drawing machines, medium drawing machines, and fine wire machine processes, you need to add wire drawing emulsion (lubricant). If the emulsion (lubricant) remains on the surface of the copper wire and is not handled well, long-term contact with the air copper surface will cause oxidized discoloration (black).

3. Construction and installation

Some users do not standardize the construction when laying and installing cables, which is easy to cause mechanical damage. Civil construction on the directly buried cable is also very easy to damage in operation. If the local damage place of the copper wire is exposed to underground moisture or the bare surface for a long time, oxidation discoloration (black) will occur.