High voltage ceramic capacitor with the same specifications, why are the prices of different materials so different?

Why do high-voltage capacitors of the same specification differ in price by about 10 times due to different materials? The customer told me that a supplier’s quotation for this high-voltage ceramic capacitor is 3.8 yuan. But what you quoted is a high-voltage capacitor made of N4700 material, the price is 42 yuan, why?

It turned out that the high-voltage ceramic capacitors used by the guests are used as the capacitor components 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, let’s compare the performance of high-voltage ceramic capacitors in terms of insulation resistance, loss angle, temperature characteristics, etc.:

Temp

Characteristics

Temp. Range

(℃)

Insulation Resistance

(≥MΩ)

Dissipation Factor

Temp. Coefficient

UJ

-25~+85

100000

6×10 -4

+/-520PPM

SL

-25~+85

100000

6×10

+/-650PPM

X5F(B)

-40~+125

100000

1%

+/-5%

X7R(B)

-40~+125

100000

1.5%

+/-10%

N4700

(DL)

-25~+85

200000

0.2%

+/-28%

-40~+105

200000

0.2%

+/-33%

Y5T(D)

-25~+85

100000

1%

+22/-33%

Y5U(E)

-25~+85

10000

2%

+22-56%

Y5V(F)

-25~+85

10000

2%

+22-80%

It can be seen from the above table that the highest insulation resistance is the high-voltage capacitor made of N4700 material, and the worst performance should be Y5U or Y5V. The insulation resistance differs by a factor of 20. The greater the insulation resistance, the greater the overcurrent capability. Therefore, in terms of current, N4700 is obviously the best material.

Furthermore, it can be seen from the above table that in terms of dielectric loss, the loss of high-voltage ceramic capacitors made of N4700 is 10 times smaller than that of Y5V or Y5U. This shows that the stability of the N4700 is much better.

In addition, in terms of temperature characteristics, the maximum change rate of Y5V or Y5U can reach -55~-80%, which is quite scary data compared to about 20% of N4700. Such a large rate of change, in fact, when working in the line, there will be a failure.

Finally, let’s analyze the size aspect. The customer said that the supplier provided Y5V before, and the diameter was within 16~MM. And our product is N4700, the diameter is 32MM. Double the size.

According to the above analysis, it is recommended that guests use N4700 material. If the cost must be considered, then consider Y5T, which is not very different.