1. You can observe with the naked eye, the color and texture of the selected material: as far as the silicon steel core is concerned, the oriented cold-rolled oriented silicon steel sheet is generally used, which is generally gray and has no orientation. High-quality silicon steel sheets are generally white, and the hot-rolled surface generally has grains.
2. Look at the thickness: the thinner the silicon steel sheet, the better the quality, because the eddy current loss generated is lower.
3. Look at the manufacturing process: whether the surface of the iron core is smooth and flat, whether the thickness is uniform, whether there are burrs in the cutout, etc.
4. Look at the parameters: Generally, different iron cores use the same power, and the smaller one is better.
5. Look at the quality of the insulation layer: this is very important, to reduce multi-point short circuits to a certain extent, you can also use special instruments (resistance measuring instrument, megohmmeter to shake Table) Check whether there is insulation between parts and silicon steel sheets.
6. To judge the quality of the iron core, you can also apply the iron core in the transformer for simulation test. According to the design plan of the transformer, wind a certain turn on the surface of the iron core The number of coils is passed through the corresponding alternating current, and judged by the magnitude of the measured current. The smaller the no-load current, the better the quality. In addition, you can also feel the temperature change during the operation of the transformer through the load test. If the temperature rises high, it means that the iron loss is large, and you can judge whether there is noise.
7. If conditions permit, the magnetic loss of the iron core can also be tested by a power consumption tester. The smaller the magnetic loss, the better the quality of the magnetic core. On the contrary, the quality worse.
