Brief introduction of cable variable frequency series resonant AC withstand voltage test device

At present, there are more and more XLPE XLPE insulated power cables in the world and domestic to replace the original oil-filled paper-insulated power cables. However, the test method before the cross-linked cable was put into operation was still based on the test method of DC withstand voltage due to the large capacity of the test and the test equipment. In recent years, the research results of many international and domestic research institutions have shown that DC test has different degrees of damage to XLPE XLPE cable. The XLPE insulated cable will cause serious damage to the insulation even if it does not break through the DC test. Second, the applied DC voltage field strength distribution is different from the operating AC voltage field strength distribution. The DC test can not truly simulate the overvoltage of the cable under running conditions, and effectively find the defects of the cable and cable joint itself and the construction process. Therefore, the use of non-DC method for the voltage test of cross-linked cables has received more and more attention. For this reason, our company has developed and produced cable variable-frequency series resonant AC withstand voltage test device.

Education Projector

Educational projectors are mainly aimed at classroom teaching by school teachers; traditional projectors are not easy to carry. Due to the naughty students in school classrooms, projectors are not safe to place in classrooms and are easily damaged by students. The portability of educational micro-projectors makes up for teaching Vacancy, it is convenient for teachers to give lectures and only need to store the materials in the projector and show them to students for teaching, saving the trouble of textbooks and handwriting with pens and chalks. Its general weight will not exceed 0.2Kg, and some do not even need fan cooling or ultra-small silent fan cooling.

Educational projectors need to have:

1. Clear handwriting Educational projectors most often display text and images, at least a resolution of 1024*768 or more, and a contrast ratio of more than 3000 lumens, so that students in the back row can see the projection clearly

2. Short-focus large screen;

3. Accurate color;

4. Easy operation;

5. Features such as multiple connection methods.

education projector,education use projector,smart education projector,best education projectors,projector for education

Shenzhen Happybate Trading Co.,LTD , https://www.szhappybateprojector.com