Capacitor Markings

Capacitor Markings

Capacitors are often marked with codes to show the value, tolerance and
material. This is particularly true for small types such as ceramic disc or
polystyrene where there is little space for full markings.

Value Codes:

The capacitance value is often marked using a 3 digit code. This works in the
same way as resistor coding but using numbers instead of colours. The first 2
numbers give the value and the last number is the multiplier.

These give the
value in Picofarads (pF), e.g. code 103 = 1 0 000pF (=0.01uF – see Capacitance
Conversion Table). Alternatively the value may be marked directly, for
example 2n2 is 2.2 Nanofarads (nF).

Tolerance Code:

A single letter is often used to indicate the tolerance of the component.
These can be translated using the following table:

Material Code:

The dielectric material is often marked in abbreviated form. The table below
shows the meaning of these abbreviations.