Types of capacitor

Very Simple Method to Read Value of Capacitor

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ceramic capacitor e1585551073916

Method of Finding the value/Meaning of codes of capacitor

Click Here For Resistor Color Code And SMD Resistor Code 

•  Ceramic disc capacitors have two to three digits code printed on them.

•  The first two numbers describe the value of the capacitor and the third number is the number of zeros in the multiplier.

•   When the first two numbers are multiplied with the multiplier, the resulting value is the value of the capacitor in picofarads.

•  If there is only two number,  it means there is no multiplier, Then you just read the value of the first two numbers in picofarads.

•  If any capacitor has 10 printed on it- Then its value is 10 PF

•  When Any capacitor has 104 printed- It has a multiplier of 4 (Third number of code ). 10 is multiplied by 10×104 =10000.  Then its value is 10×10000= 100000PF

Here is a Table of Mostly Used Codes of Ceramic Capacitor and their unit conversion in Micro, Nano, and Picofarad

how to read capacitor code value

The last number is the power of 10 and multiply with the first two no.

If a capacitor has 682 code – first check the last no, here the last no is 2. Now  the multiplier is 102

For example—

  • 204 = 20×104 = 200000 PF
  • 472 = 47×102 = 4700 PF
  • 502 = 50×102 = 5000 PF
  • 330 = 33×100 = 33 PF   [100 = 1]

 

UNITS—

  • 1000 nanofarad(nF) = 1 microfarad(µF)
  • 1 picofarad = 10-12farads.
  • Nano= 10-9
  • Micro= 10-6
  • 1 Nano Farad= 10-9 Farad
  • 1 Microfarad (µF)= 10-6 Farad

1 nF = 1000 pF
1 pF = 0.001 nF

Example: 

convert 15 nF to pF:
15 nF = 15 × 1000 pF = 15000 pF

Codes of Polyester Film and Metallized Film Capacitor

If a capacitor is marked with 2A474J, the capacitance is decoded as described above, the two first signs is the voltage rating and can be decoded from the table given below here. 2A is a 100VDC rating according to the EIA (Electronic Industries Alliance) standard.

A second letter will be a temperature coefficient if it’s present.

Some capacitors are only marked as 0.1 or 0.01, mostly in these cases the values are given in uF.

Some small capacitance capacitors can be marked with an R between numbers. If code is 3R9 then R is an indicator of values Less than 10pF and has nothing to do with resistance. 3R9 would be 3.9pF.



 Capacitor code table tolerance and voltage

Metalized film Capacitor code



105j400v capacitor

105J=10×105 =1000000pf=1000nf=1.0uf

j= +/- 5% Tolerance

polyester film capacitor 

104= 10×104= 100000pf=100nf=0.1uf

j=+-5% tolerance

2A= 100VDC voltage rating

 

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10 thoughts on “Very Simple Method to Read Value of Capacitor”

  1. What would the capacitance be for a small through-hole ceramic cap with the code B21 and a horizontal under the code?

    1. B21 (CBB21) is not capacitor value, this is material specification of capacitor given by manufacturer.
      CBB21 denoted Metalized Polypropylene Film capacitor, This is also a type ceramic capacitor

  2. Hi, I have a polyester film capacitor like the one you are showing here in green colour but mine is red and same shape.
    Marking is:
    104K
    100N 100V? N?

    104K I know now but the 100N under I can’t decipher. Is it 100V? but the N is still puzzling me. I can’t find on the web any cross for the bottom code.
    The top of the cap shows darker edge of the coiled film through the red paint (not cracked) and I don’t see it on any others.
    Thanks in advance.

  3. Hi, Thanks for the content. There is an error on the ceramic capacitors code table.
    5.6nF should be 0.0056uF instead of 0.056uF.

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