For the terminal wire tester, the surface is not an easy task. The standard of the important surface test is not easy to grasp. If the same product is tested by different inspectors, different conclusions may be obtained. Even so, as long as we really learn to master the standard, continue to accumulate experience, and can use the standard sample for testing when necessary, we can do a good job in surface testing of products.

Conditionally test the roundness level to see if there are defects such as folding, rounding, cracks, inclusions, kinks, and major mechanical damage spots, pits, peeling, flash, corrosion black spots, etc.

Whether the surface is smooth and clean, and whether there are triangle, burr, crack, fold, inclusion, major scar, pitting, mechanical damage, corrosion black spots and other phenomena. It is worth mentioning that there is also the oxidation level of copper wire. Ordinary golden yellow is normal, light red is slight oxidation, and the surface is dark red and blue is major oxidation. Any phenomenon showing major oxidation should be judged as waste. The aluminum wire shows a lot of defects in the production process, so the overhead transmission line should be strictly controlled.

On the surface of aluminum wire, the wire shall be tightly and neatly twisted without looseness, kink, jump or protruding of single wire, and fracture of single wire. In addition, the joint welding of single line should be round and the welding has been qualified for anti-corrosion treatment. Most of the joints should not exceed twice the diameter tolerance. The spacing length between the two welding points of single line joint should also meet the standard. The spacing between the two welding points of single line should not be less than 15 meters. The spacing between the two welding points of single line should not be less than 5 meters in the inner layer and not less than 15 meters in the outer layer. When the copper core is a single copper wire, welding is not allowed. 4 Surface layout dimension of terminal wire

The test of the surface and layout size of the terminal wire is usually conducted alternately or at the same time. The quality of the product depends on whether its function is good or not, but the quality of its surface and layout size also accounts for a certain proportion. The surface and layout size of the product interfere with the function of the terminal wire.

1. Local thinning will cause local fever, increase resistance and accelerate the aging of insulation.

2. Oxidation rust black spots, interference with conductor joints, increased resistance, and easy aging of insulation.

3. Bump or scratch the mechanical strength of interference conductor.

The surface test of terminal wire is to test the surface phenomenon of products, semi-finished products or data, and the size test is to review each product according to the size of each part specified in the product standard. Layout test refers to the test of the layout of each component of the terminal wire. The surface test, such as the oxidation of copper wire, can interfere with the quality of the terminal wire, and the size can directly interfere with the function of the product. For example, the outer diameter of the conductor is related to its resistance; Insulation thickness and resistance are related to withstand voltage level; Strand pitch is related to the flexibility and firmness of the product.

The test can reveal the manufacturing quality of the terminal wire and feel the difficulties in the production process. Therefore, the energy-saving surface and layout size are the guarantee of the product function.