Low Frequency Transformer Heat Resistance Grade
Low Frequency Transformer Heat resistance grade
EI-type transformer is the most commonly used components in the industry, is the isolation transformer, control transformer and PCB transformer often selected structure, by the skeleton, iron core, wire and fixed bracket structure, simple structure, suitable for mass production, now Let's talk about the EI-type transformer prone to failure and the reasons.
1: Transformer power on vibration and abnormal sound, possible reasons: a transformer is not dipped paint or dipping is not complete; b. Transformer iron chip is not tight.
2: Transformer no-load current and loss become larger, the possible reasons: a. Is the transformer core interchated in place, the gap is too large; b.EI chip grades are too low, the quality of the chip.
3: transformer voltage test failed, may be the transformer skeleton damage or creepage distance is not enough.
4: Transformer heat or short circuit, the possible reason is that the coil in the winding process is not tight to debug the most appropriate, resulting in enameled wire damage.
There are many reasons for the failure of the EI transformer, and it is complicated. To accurately determine the abnormal and fault, you need a dedicated transformer test equipment to a comprehensive analysis in order to accurately find the reasons, test engineers work experience is also very important. Enameled wire is one of the most important raw materials for transformer manufacturing. In the actual production, it is necessary to paint the paint layer for easy welding. Today, give you talk about the transformer enameled wire to paint the method
There are three main ways to paint:
1, the use of chemical reagents (paint agent), Disadvantages: corrosive.
2, mechanical paint, shortcomings: low efficiency, labor intensity.
3, laser burning, shortcomings: investment, low efficiency.
The insulation grade of the toroidal transformer is determined by the heat-resistant grade of the insulating material. The heat-resistant grade is divided into A, E, B, F and H. Insulation class is divided into A grade E grade B grade F grade H, corresponding to the maximum allowable temperature (℃) were: 105 120 130 155 180. In the transformer work, the insulation level is the most fragile link, it is most vulnerable to high temperature and reduce the service life.
So how does a transformer life verify? Transformer work failure is often due to the failure of the transformer insulation system, in the transformer design has a "8 degrees experience" for reference to measure the life of the transformer, the same transformer when the working temperature for every 8 degrees rise in half the principle of life, with This method in the laboratory can be roughly tested the life of the transformer.