guest response: why do high-capacity high-voltage ceramic capacitors have various problems in use? for example, 30kv20nf capacitors often only reach 20kv, which is easy to cause problems. is the voltage not up to standard? actually, this is not the case, different the use environment will cause use problems.
for example: after a foreign trader purchased a high-voltage ceramic capacitor of 30kv20nf, it was soon told that this 30kv capacitor has a problem with the withstand voltage and will be broken after working for two minutes at 24kv.
this is impossible! we must know that after repeated testing inside our company, the maximum withstand voltage of this capacitor can reach 60kvdc. where is the problem with good luck? we let the customer give us a detailed description of the use and find several problem:
first of all, the frequency is wrong. the capacitor required by the guest is used in the high-frequency pulse circuit, and the frequency exceeds 300khz. our product can only be used in circuits below 50khz. so high frequency, it is called the problem without problems. this is related to the first choice when the customer chooses the product: the choice of materials. we can not only look at the surface data of the capacitor: voltage and capacity. the more important data is frequency, temperature, partial discharge, ac and dc voltage, current. there is a problem with the selection of the guest. according to his frequency requirements, he should choose at least y5t material, or better n4700 material. of course, these better porcelain can not achieve such a large capacity. it doesn't matter, we would advise guests to use more than one parallel.
secondly, the current is not right. the working voltage is 24kv, which is achievable. the problem is that the working current is large during the use of the guest, which is beyond the range of the capacitor.
in addition to the above reasons, we also remind our customers that the choice of capacitors should be considered from the overall scheme of the circuit, rather than from a component. pay attention to the environment when using it, for example, in transformer oil, in the ring. oxygen resin. frequency, ac and dc voltage, current, temperature, partial discharge, leakage current requirements, etc., should be considered comprehensive, to be sure: is this large-capacity capacitor i used suitable?