Axial Ceramic Capacitor Markings

Early on capacitors were expensive and the parameters were printed on the case sometimes partly by hand.

Axial ceramic capacitor markings. The smallest capacitors made from ceramic film or tantalum use units of picofarads pf equal to 10 12 farads. Over the years people have used a bewildering number of ways of marking capacitors. Two of the most common are shown here. The top 683 marking indicates the capacitance value which is 68 000 picofarads pf.

To get this value you multiply the leading digits 68 in this case by 10 raised to the power of the last digit 3 and the result is the capacitance in picofarads in this case we get 68x10 3 pf. Ceramic capacitors are generally smaller than types like electrolytic capacitors and therefore the markings need to be more concise. Capacitors it is marked as np on the capacitor for example npa or npr where np stands for non polarized a stand for axial and r stands for radial. This indicates a 22µf capacitor with a maximum voltage of 6v.

Markings made on the capacitors help identify the polarity. High voltage ceramic dc disc capacitors with axial leads 10 kvdc to 30 kvdc. A variety of schemes may be used. In addition to the capacitance value and possibly the working voltage or breakdown voltage the capacitor may be marked by its tolerance.

Offered in radial axial sip and 2 pin dip configurations avx leaded mlccs offer excellent mechanical shock and vibration resistance in harsh environment applications. With a wide range of dielectric materials capacitance values voltage ratings and lead styles avx leaded ceramics are available in molded or. Typically the markings on a capacitor may give the figures like 22 and 6v. Larger capacitors the cylindrical aluminum electrolyte type or the double layer type use units of microfarads uf or µf equal to 10 6 farads.

The stripe marking on a capacitor can also be accompanied by the symbol of an arrow pointing towards the negative side of the lead. Axial style capacitors are not used very often but are interesting in how they are marked. The first is used with small ceramic capacitors and appears as a single letter. A negative or cathode band runs down the side of them similarly to the radial style but there is an arrow in the marking that indicates which side is negative or the cathode.

With the commercialization of small cheap capacitors some people switched to use color. These are the most widely preferred capacitors because of its small sizes. 7 is not. The positive lead of a leaded titanium capacitor is denoted by the polarity markings on the capacitor.

Pth axial electrolytic capacitor. Some of the earliest even had some parameters molded on the case. The above image shows a mylar film capacitor.