Understanding The Number on Ceramic Disc Capacitor’s
What does the capacitor number mean?
Ceramic disc capacitors come with a 3 digit number printed on them, this number is used to determine the capacitance of the capacitor. As the ceramic disc type capacitors are small, they are measured in picoFarads (pF).
Calculating the capacitance from a ceramic capacitor’s number
The way in which we calculate the capacitance is by breaking the number down into 2 parts, The first part is the first 2 digits give us the first part of the value, followed by the last number which indicates how many zeros we add to give us the capacitance value.
For example, a ceramic disc capacitor with the number, 223 would indicate the capacitance is: 22,000pF and so on…
Converting picofarad (pF) to nanofarad (nF)
With ceramic disc capacitors being such low capacitance, the unit of measurement they use can lead to quite large numbers when recording their values, sometimes you will find it useful to convert their value from picofarad to nanofarad.
A nanofarad is made up of 1,000,000 picofarads, so the calculation requires you to divide the pF value by 1,000,000 to get the nF value.
For example, the pF value we worked out in the previous example of 22,000pF would be: 22,000 / 1,000,000 which gives us: 0.022nF.
Common ceramic disc capacitor values
|Capacitor Number||Capacitance (pF) Picofarad||Capacitance (nF) Nanofarad|