How to distinguish between ceramic capacitors and varistors

The ceramic capacitor and the varistor look very similar. They are all a small thing far away from blue. Some people do not know that the ceramic capacitor and the varistor are mixed, but the function is not normal, but it burns. Circuits, although they look like, but the function is completely different. The following small series takes you to distinguish between ceramic capacitors and varistors.

A varistor is a kind of resistance device with nonlinear volt-ampere characteristics. It is mainly used for voltage clamping when the circuit is subjected to overvoltage, and absorbs excess current to protect sensitive devices. The main function is to withstand abnormal overvoltage and protect the circuit. . The ceramic capacitor is a capacitor made of ceramic material as a medium, coated with a metal film on the surface of the ceramic, and then sintered as a high temperature. The main function is to block, couple and bypass in the low frequency circuit. And capacitors such as filters are used.

Generally, the varistor position mark on the circuit board, there are: VSR, VDR, RV and other words are varistor, and the ceramic capacitor is marked with "C". The varistor's appearance is generally blue. The size is generally 5D 7D 10D 14D 20D 25D, etc. Its surface lettering is based on XD and then followed by 10XK 2XXK 18XK and other marks, those marks indicate the withstand voltage of the varistor For example, if printed with 10D 471K, this means that it is a varistor, then the diameter is 10mm, the withstand voltage is 470V, and the error range is ten percent.

The appearance of the ceramic capacitor is also blue, and the appearance is similar to that of the varistor, but D is not used as the size. Generally, the printing is directly printed with 10X 1KV 22X 1KV, etc. For example, 102M 400V is printed, indicating that this porcelain The chip capacitance is 102. The withstand voltage is 400V and the error range is 20%.

In most cases, we can use the printing logo to identify whether it is a ceramic capacitor or a varistor, but there may be printing errors, unclear printing, no printing, etc. At this time, we must use the instrument to measure to use the business opportunity. So, in order to be guaranteed.

After reading the contents of this article, have you learned to distinguish between ceramic capacitors and varistors? If you have technical questions, please contact us and we will try our best to solve it for you.