What are the important indicators for the National Quality Supervision, Inspection and Quarantine Bureau to detect wires and cables?

The quality of wires and cables directly affects the user's electricity safety. For consumers, the quality control of wires and cables is the first priority. So what are the important indicators for testing wires and cables?

1. Cable insulation resistance:

Insulation resistance is closely related to the product's electrical strength, dielectric loss, and the gradual deterioration of the insulation material under working conditions. The insulation is dry and impermeable or damp, and contains pollution and impurities. During the operation of wires and cables, it is often necessary to detect the insulation resistance and leakage current as the main basis for whether they can continue to operate safely.

2. Cable capacitance and loss factor:

In the AC electric field, the insulator in the cable will form dielectric loss due to leakage current and various polarizations. It not only wastes electric energy, but also heats the medium (insulator) and accelerates insulation aging. Therefore, TAN is also one of the main parameters of the cable. . At the same time, through the measurement of capacitance and loss factor, various insulation degradation phenomena such as insulation moisture, insulation layer and shielding layer falling off can be found.

3. Cable partial discharge measurement:

For extruded cables, partial discharge also causes serious damage to plastic and rubber. Partial discharge is more likely to occur. As the working field strength increases, this problem becomes more serious. Therefore, high-voltage extruded cables must be tested during factory tests. Make partial discharge measurements. Generally, methods such as electrical measurement, acoustic measurement, and light measurement are used.