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Teach you how to distinguish good and bad wires and cables?

2 years ago 1697 0 News

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Distinguish the Advantages and Disadvantages of Wire and Cable


1 Wires with good weight and quality are generally within the specified weight range.


2 See if there is a quality system certificate, anti-counterfeiting mark, and whether the packaging is in good condition.


See if the certificate is standardized.


Look at the name of the factory, the site, the inspection chapter, the date of production.

See if the trademark, specifications, voltage, etc. are printed on the wire. 

Look at the cross section of the copper core of the wire. The copper color of the superior product is bright and the color is soft. 

The copper core yellow is reddish, indicating that the copper used is of good quality, while the yellowish white is the reaction of low quality copper. 

The copper core of the qualified copper core wire is purple, shiny and soft to the touch. 

The copper core of the inferior copper core wire is purple-black, yellowish or white, with many impurities, poor mechanical strength, poor toughness, and will break when a little force is applied, and the wire is often broken.


When inspecting, just peel off the wire by 2cm, then use a piece of white paper to rub it slightly on the copper core. 

If there is black material on the white paper, it means there are more impurities in the copper core. 

In addition, counterfeit and shoddy wires are often “three no products”, but there are also ambiguous indications such as manufacturing in China, manufacturing in a certain province or city in China, which is actually equal to the unproduced production.


3 It can take a wire head repeatedly bent by hand, any soft touch, good fatigue resistance, plastic and rubber feel elastic and no crack on the wire insulation is superior.


4 Take a section of the insulation layer and see if its core is in the middle of the insulation layer. 

If the power is not high, the eccentricity caused by the process is not high. If the power is small, it can be safe. 

If the power consumption is large, the thinner side is likely to be broken by the current.


The outer plastic skin of the regular product wire is bright and shiny, and the texture is fine. 

There should be no open flame when ignited with a lighter. Non-regular products use recycled plastics, with a dull color and loose texture, which can ignite open flames. 

The shoddy wire insulation layer seems to be very thick, and in fact it is mostly made of recycled plastic. Over time, the insulation layer will age and leak.


5 It is necessary to see its length and core thickness have no hands and feet. 

According to the relevant standards, the error of wire length measurement should not exceed ±0.5%, the cross-sectional diameter should not exceed ±0.1%.

The length of each roll of the mark is 100m, the error does not exceed ±2cm, and the length of non-standard products ranges from 60~80m.


6 The price, because the production cost of counterfeit and shoddy wires is low, therefore, when the sellers sell, they often sell at low prices with low prices and good quality, which makes them fooled.


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