Appearance standard, certification mark, manufacturer, wire diameter, etc. On the conductor, the yellow-green insulation layer is used for grounding wire; Mechanical strength; Sheath insulation (generally greater than 100 mω) and compressive strength (below 500V,1500 V); Conductor resistance (no more than a certain resistance under a certain wire diameter, conductivity and length) 5. When the high temperature impact is 150 degrees, the conductor should not crack at the low temperature of -30 degrees.
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High quality welding wire is usually within the specified weight range. For example, the common plastic insulated single-stranded copper core wire with cross-sectional area of1.5 mm 2, per 100 m weight1.8 ~1.9 kg; 2.5 mm^2 plastic insulated copper core wire, with a weight of 3 ~ 3 per 100 m1kg; The weight of 4.0 mm^2 plastic insulated single copper core wire is 4.4 ~ 4.6 kg per100m, etc. The wires with poor quality have insufficient weight or length, or the copper core of the wires has too many impurities.
When checking, just peel off one end of the wire by 2 cm, and then gently rub it on the copper core with a piece of white paper. If there is a black substance on the white paper, it means that there are many impurities in the copper core. In addition, the insulation of fake and inferior wires seems to be very thick. In fact, most of them are made of recycled plastics. Over time, the insulation layer will age and leak electricity.
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