Important indicators of wire and cable testing equipment

Wire and cable Testing Equipment is an important part of the national standard wire and cable. The more advanced the quality inspection department within a wire and cable company, the better and more trustworthy the wire and cable produced by the company. The stricter the third-party quality inspection department, the more conducive to the development of this industry.

The following are several important indicators of wire and Cable Testing Equipment, which are the most critical indicators for measuring wire and cable.

①Measurement of wire DC resistance:

The conductive core of wire and cable mainly transmits electrical energy or electrical signal. The resistance of the wire is the main indicator of its electrical performance. The core resistance of the wire is larger than that of the DC voltage due to the skin effect and the proximity effect surface when the AC voltage is applied, but the difference between the two is very small when the electric eye frequency is 50Hz. Now the standard stipulates all of them can only be required to detect whether the DC resistance or resistivity of the wire core exceeds the value specified in the standard. Through this inspection, some defects in the production process can be found: such as wire breakage or part of the single wire breakage; Conforms to standards; incorrect length of product, etc. For power cables, it can also be checked whether it will affect the allowable current carrying capacity of wire and cable products in operation. There are single-arm DC resistance method and double-arm DC bridge method for the measurement of conductor DC resistance, and the accuracy of the latter is higher than that of the former. The testing steps are also more complicated than the former.

②Insulation resistance test:

Insulation resistance is an important indicator that reflects the insulation characteristics of wire and cable Testing Equipment products. It is closely related to the electrical strength of the product, dielectric loss, and the gradual deterioration of insulating materials under working conditions. For communication cables, if the insulation resistance between lines is too low, it will also increase loop attenuation, crosstalk between loops, and long-distance power supply leakage on the conductive core. Therefore, the insulation resistance should be higher than the specified value. Determination of insulation resistance can find defects in the process, such as insulation dry and impervious or sheath damaged and damp; insulation is polluted and mixed with conductive impurities; insulation layer cracking caused by various reasons, etc. In the operation of wires and cables, it is often necessary to detect insulation resistance and leakage current as the main basis for continued safe operation. At present, in addition to the ohmmeter (shake meter), the commonly used galvanometer comparison method is the high resistance meter method (voltage-current method) to measure the insulation resistance of wires and cables.

③Aging and stability test:

The aging test is a stability test that can maintain stable performance under the action of stress (mechanical, electrical, thermal). Thermal aging test: The simple thermal aging test is to test the aging characteristics of the sample under the action of heat. The sample is placed in an environment with a temperature higher than the rated working temperature, and after a specified time, some sensitive properties are measured. The change before and after aging was used to assess the aging characteristics. It is also possible to accelerate the aging of the test sample by increasing the temperature, and add thermal, mechanical, and electrical stresses such as moisture, vibration, and electric fields to form an aging cycle. After each aging cycle, certain selected sensitive performance parameters are determined. until the performance drops to the value of the indicated life. In this way, at a higher temperature T, a shorter lifetime L (the time for the sample to be heated) is obtained. Thermal stability test: The thermal stability test is that the cable is heated by current and also bears a certain voltage. After a certain period of heating, some sensitive performance parameters are measured to evaluate the stability of the insulation. Insulation stability test is divided into long-term stability test or short-term accelerated aging test. Responsible enterprises think about how to improve the product quality of their own enterprises to improve the market competitiveness of their own products. Product quality is the foundation of enterprise production and development, especially in the wire and cable industry.

    The information about wires and cables is introduced here. I hope this article will be helpful to you. For more information, please pay attention to the official website www.testingfire.com