Several important indicators for wire and cable quality inspection

For the quality inspection department, testing whether the wire and cable is qualified may need to test more than two dozen items, and for a cable, the following 6 important measurement items play a key role in determining its quality
.

1.
Measurement of DC resistance of wires:

For wire and cable, the conductor part is its most important component
.
The conductive core of wire and cable mainly transmits electrical energy or electrical signals
.

The resistance of the wire is the main indicator of its electrical performance, and now the standard stipulates: detect whether the DC resistance or resistivity of the wire core exceeds the value
specified in the standard.

The main purpose of this inspection is to detect certain defects in the production process, such as broken wires or some of the single wire breaks; The wire section does not meet the standard; The length of the product is incorrect, etc
.

In addition, for power cables, this inspection can not only detect the condition of the conductor, but also detect whether the conductor has an effect
on the allowable ampacity of the wire and cable product operation.

2.
Test of insulation resistance:

Insulation resistance reflects the important indicators of the insulation characteristics of wire and cable products, which is closely related
to the electrical strength of the product, dielectric loss, and the gradual deterioration of the insulation material in the working state.

Measuring insulation resistance can find defects in the process: such as insulation drying and impermeable or sheath damage and moisture; Contamination of insulation and mixing of conductive impurities; Cracking of the insulation layer caused by various reasons, etc
.

For communication cables, too low insulation resistance between lines will also increase loop attenuation, crosstalk between loops, and long-distance power supply leakage on the conductive core, so the insulation resistance is required to be higher than the specified value
.
In the operation of wires and cables, it is often necessary to detect insulation resistance and leakage current as the main basis
for whether safe operation can continue.