High-voltage ceramic capacitors have the same spec

Everything is the same, different materials, different prices, everyone knows this. However, the high-voltage capacitors of the same specification, depending on the material, when the price difference is about 10 times, how to treat it? The customer told me: Laohe, the price quoted by the supplier for this high-voltage ceramic capacitor is 3.8 yuan. But you reported that the high-voltage capacitor of N4700 material, the price is 42 yuan, the gap is too big, please help me explain!
Originally, the high-voltage ceramic capacitor used by the guest was used as a capacitor component of the high-voltage generator, with a nominal capacity of 2200PF2500PF, a rated voltage of 35KV, and a diameter of 16~25MM. The price is only 3.8 yuan. The material is Y5V. After use, it is found that the capacitor will fail within one month.
According to different product materials, we compare the insulation resistance, loss angle, temperature characteristics of high-voltage ceramic capacitors:

As can be seen from the above table, the highest insulation resistance is the high voltage capacitor of N4700 material, and the worst performance should be Y5U or Y5V. The insulation resistance differs by a factor of 20. The larger the insulation resistance, the greater the overcurrent capability. Therefore, in terms of current, it is obvious that the N4700 material is good.
Furthermore, as can be seen from the above table, in terms of dielectric loss, the high-voltage ceramic capacitor of N4700 material has a loss 10 times smaller than Y5V or Y5U. This shows that the stability of the N4700 is much better.
In addition, the temperature characteristics, Y5V or Y5U change rate can be up to -55 ~ -80%, compared to about 20% of the N4700, this is a rather scary data. With such a large rate of change, when it actually works in the line, it will fail.
Finally, let's analyze the dimensions. The guest said that the supplier provided the Y5V with a diameter of 16~MM. And our product is N4700, the diameter is 32MM. Double the size.
Choosing a capacitor to judge whether it is suitable for your own product, you must be like the old one, carefully compare the above parameters, and carefully analyze and analyze. The price is nothing, the key is whether it can be used. Take the N4700 high-voltage ceramic capacitor and Y5V's price comparison, not at the same level, more importantly, take a product that is completely out of the requirements of your own use to compare the N4700, this is not comparable, if you must compare, please take All can be compared to products that are normally used.
According to the above analysis, it is recommended that guests use the material of N4700. If you must consider the cost, then consider the difference is not very big Y5T, the parameters of the two aspects are relatively close, and the price of Y5T is still acceptable. For 35KV2200PF, the price should be around 30 yuan, so this price is still acceptable.