Capacitor Codes and associated Markings
voltage and tolerance along with their values is represented by different types
of markings and codes. Some of these markings and codes include capacitor
polarity marking; capacity colour code; and ceramic capacitor code
done on the capacitors. The markings’ format is dependent upon what type of
capacitor is given.
types of the codes used. The component deciding the coding can be surface
mount, technology, traditional lead, or capacitor dielectric component.
factor which plays a role in deciding the marking is the size of the capacitor
as it impacts the space which is available for capacitor’s marking.
a crucial role in providing standardized systems of marking the capacitors
which can be followed as a standard in the industry.
Basics of Capacitor Markings
which are followed while marking the capacitors.
The various manufacturers
manufacturing specific types of capacitors follow both basic or standard
marking systems depending on the type of capacitor being manufactured and what
is the best fit for it.
on many occasions.
MFD is not used for denoting “MegaFarad” as is the general
capacitors if the person has a general knowledge of the marking and coding
systems used for the capacitors.
followed for marking the capacitors are:
processes adopted to mark the parameters of a capacitor is to create a marking
on the case of the capacitor or encapsulating them in some manner.
feasible and suitable for capacitors of large size as it enables to provide
enough space for creating the marks.
which are small in size does not provide space required for clear markings and
only few figures can be accommodated in the given space in order to mark it and
provide a code for their various parameters.
used in such cases wherein three characters are used to mark the code of the
capacitor. There is a similarity between this marking system and the resistor’s color codes system which can be observed here, except for the “color” which
is used in the coding system.
system, the first two characters represent figures which are significant and
the third character is representative of a multiplier.
are tantalum, ceramic, or film capacitors, “Picofarads’ is used to denote the
capacitor’s value; while in case the capacitor is of aluminium electrolytes,
“Microfarads” is used to denote the capacitor’s value.
In case, small values
with decimal points needs to be represented, then the alphabetical letter “R”
is used such as 0.5 is represented as 0R5, 1.0 as 1R0, and 2.2 as 2R2
the surface mount capacitors where there is very limited space available.
old. In the present times, industry rarely use colour code system except seldom
on some of the components.
capacitors. The tolerance codes used in the capacitors are similar to the codes
used in the resistors.
capacitor is one of its key parameter. This coding is used widely in various
types of capacitors, especially for the capacitors which have enough space to
write alphanumeric codes.
space available for alphanumeric coding, there is absence of voltage coding and
thus any person handling such capacitors must take extra care when he/she
observes that any kind of marking is absent on the storage container or the
electrolytic capacitor use a code consisting of one single character.
coding system is similar to that of the standard system followed by EIA and
also requires very small amount of space.
marked or coded in a manner which denotes the capacitor’s temperature
are in most of the cases the standard codes given by the EIA.
temperature coefficient codes which are used in the industry by different
manufacturers, especially for capacitors including film and ceramic type of
(parts per million per degree C).
Polarity Markings of a capacitor
their polarity. In case the polarity markings are not provided to the
capacitors, it may result in severe damage being caused to the component along
with the entire circuit board.
that there are polarity markings on the capacitors when the latter is inserted
into the circuits.
are made of tantalum and aluminium electrolytes. A capacitor’s polarity can be
easily determined if they are marked with signs such as “+” and “-“. Most of
the capacitors which are circulating in the industry recently possess such
capacitors, especially electrolytic capacitor is the by marking the components
A stripe marking denotes a “negative lead” in an electrolytic
the symbol of an arrow pointing towards the negative side of the lead. This is
done when axial version capacitor is present where both ends of the capacitor
consist of lead.
by the polarity markings on the capacitor.
The polarity marking is marked near
the positive lead with a “+” sign indicating the marking. In case of a new
capacitor, an additional polarity marking is placed on the capacitor to denote
that the negative lead is shorter than the positive lead.
it on the capacitor. This is true for capacitors which provide enough space for
marking to be printed and include film capacitors, disc ceramics, and
These large capacitors provide sufficient space to
print markings which shows the tolerance, ripple voltage, value, working
voltage, and any other parameter associated with the capacitor.
between the markings and codes of the various types of lead capacitors are very
minimal or marginal; but nevertheless these differences are many in number.
manufactured in both large and small sizes. But the large leaded capacitors are
and others can be provided in detail instead of giving in abbreviated form. On
the other hand, for the smaller capacitors due to lack of sufficient space the parameters
are provided in the form of abbreviated codes.
a capacitor is “22µF 50V”. Here, 22µF is the value of the capacitor while 50V
denotes the working voltage. The marking of a bar is used to denote the
polarity of the capacitor indicating the negative terminal.
(µF)” is used to mark the values in the leaded tantalum capacitors. An example
of a typical marking observed on a capacitor is “22 and 6V”. These figures
indicate that the capacitor is of 22µF and 6V is its maximum voltage.
capacitor are more concise in nature since it is smaller in size as compared to
of schemes or solutions are adopted. The value of the capacitor is indicated in
denotes that the capacitor is of 10nF. In a similar way, 0.51nF is indicated by
the marking n51.
surface mount capacitor do not have sufficient space available for markings due
to their small size.
manner that any type of marking is not required. These capacitors are loaded in
a machine called pick and place which eliminates any marking need.
capacitors, there is absence of markings which are observed in some of the
capacitors only consist of the polarity markings. This is present in order to
ensure the correct insertion of the capacitor in the circuit board.
used for the capacitors which has sufficient space available such as is evident
in the ceramic capacitors.
capacitors across their one end denoting the capacitor’s polarity.
for polarity is important in order to identify and check the capacitor’s
polarity since the destruction of the capacitor can occur if the polarity is
not known and a person places it in reverse biasing, especially in the case of
check a capacitor’s value.
Since there are a range of capacitors available and
their different coding and marking systems, it is quintessential that a basic
understanding of these marking and coding is there to an individual in order to
apply it appropriately to respective capacitors.
the capacitor’s value with practice and experience and just going through few
examples mentioned here would not suffice.