Common Faults And Prevention of PVC Insulated Wires: Analysis of Cracking, Aging, And Breakdown

In modern electrical systems, PVC insulated wires are widely used in building wiring, home appliances, automobiles, and industrial control fields due to their moderate cost, good flexibility, and good flame retardancy. Despite its excellent performance, if the selection or use is improper, the PVC insulation layer may still suffer from cracking, aging, breakdown, and other faults, which directly affect the safety of electricity use and the stability of equipment. This article will combine typical product cases to deeply analyze the causes of these common problems and propose effective preventive measures.

Common fault phenomena of PVC insulated wires

1.Cracking

Under the influence of mechanical stress or ambient temperature difference for a long time, the outer sheath of the PVC hook up wire may have longitudinal or annular cracks, which may affect the insulation performance at the least and expose the conductor at the worst.

2.Aging

In high temperature, ultraviolet rays, and chemical corrosion environments, the plasticizer in the flexible PVC wire will gradually volatilize, and the insulation layer will harden, discolor, and lose flexibility.

3.Electric breakdown

When the voltage exceeds the insulation tolerance range, or the insulation layer becomes thinner due to defects, short circuits and spark discharges may occur, which may cause fires in severe cases.

Understanding the above-mentioned causes of failure will help us avoid risks in advance during selection, installation, and maintenance.

Causes and preventive measures for cracking

1. Excessive installation tension

During the process of pipe threading or bending, if the insulated flexible wire cable is subjected to a force exceeding the specified tension, the outer layer is easily torn.

Prevention:

• Use reasonable traction tools during installation to avoid violent pulling.

• Select a pipe groove with a bending radius that meets the standard.

2. Low-temperature embrittlement

The construction environment temperature in winter is too low, the flexibility of the PVC material decreases, and it is easy to crack.

Prevention:

• Under low temperature conditions, first heat and soften the cable.

• Use a PVC sheath with a low-temperature flexible formula.

Causes and prevention of aging

1. Long-term high-temperature operation

Exceeding the rated insulation temperature (such as UL1571 is only 80°C) will accelerate aging.

2. Ultraviolet exposure

If there is no protection when laying outdoors, ultraviolet rays will decompose the PVC molecular chain.

Prevention:

• Choose high-temperature resistant multi-core copper wire (such as UL10070 with a temperature resistance of 105℃) according to the application scenario.

• Anti-UV sheaths or additional wire tubes are required for outdoor environments.

Analysis of the causes of electrical breakdown

1. Voltage overload

Using plastic coated electrical wire that does not meet the rated voltage level is very easy to break down. For example, using 30V grade wire for 220V line.

2. Installation damage

Insulation layer is cut during installation, or metal edge scratches the sheath.

3. Moisture erosion

Moisture or chemicals penetrate the insulation layer and reduce insulation resistance.

Prevention:

• Select the correct model according to voltage requirements.

• Check whether there are sharp objects in the construction environment.

• Moisture-proof technology is required in wet areas.

Comparison of typical PVC wires: UL10070 and UL1571

The following table compares the performance and application scenarios of two commonly used PVC insulated wires to help you accurately select the model during design:

Selection and maintenance points

To effectively reduce the risk of PVC insulated wire failure, it is necessary to start from the whole process of selection, installation and maintenance:

1.Accurately match the use conditions:

• Voltage, current, temperature and flexibility requirements should be checked one by one.

• Multi core copper wire and thick cross-section products are used in high current situations.

• When multi-core control wire is required, PVC 2 core wire or multi-core variants can be selected.

2.Reasonable layout and laying:

• Avoid excessive bending of cables.

• The installation should be away from heat sources, oil stains or highly corrosive chemicals.

3.Regular inspection:

• Regularly check the appearance of PVC insulated wire, and replace it in time if there are cracks or hardening.

• Use an insulation resistance tester to test performance.

4.Storage and transportation:

• PVC hook up wire is prohibited from heavy pressure and moisture during transportation and storage.

• Room temperature and dry environment can extend the service life.

Conclusion

PVC insulated wire is still one of the most common insulating materials in the world, and is widely used in various product forms such as flexible PVC wire, plastic coated electrical wire, and insulated flexible wire cable. However, it must be clear that high-quality wires also need scientific use and regular maintenance to give full play to their performance.

By deeply understanding the causes of cracking, aging, and breakdown, and rationally selecting different types of PVC wires (such as UL10070, UL1571), and coordinating standardized construction and inspections, enterprises and users can greatly reduce the failure rate and ensure the safety of equipment and personnel. In the future, with the promotion of new environmentally friendly flame-retardant PVC, these problems will gradually be further improved.

If you need more PVC insulated wire solutions or product technical information, please contact 3F, we will help you ensure that the project wiring is both safe and efficient.