electroSome

Capacitor Codes

Manoj Shenoy

Electronics deals with circuits and the one who deals with it should be aware about each and every component used. Not only the component but also its values matters the most. Slight change in value will lead to terrible errors, so to avoid that problem one must be aware of selecting the component values and to check whether it is right or not.

Most of us is aware about resistor color code but only few know to identify the capacitance values. So here I’m going to discuss how capacitor codes are identified.

Generally for large capacitors, the actual values of Capacitance, Voltage or Tolerance are marked in the body of the capacitors in the form of alphanumeric characters.

But for smaller disk capacitor (ceramic capacitor) along with plastic film capacitors usually comes with very small values ranging in Pico and Nano farads. We usually see 3 numbers along with an alphabet along with it.

We usually got confused about how to understand the values of such capacitors. 

Types of Capacitor Codes

The capacitor manufactures uses two methods of coding :

  1. Color coding
  2. Number coding

Color Coding

The unpolarised mica and polyester molded capacitors are color coded, similar to the color coding of resistor. The color is noted from Top to Bottom. The first color is considered as 1st digit, second color obviously 2nd digit, the third one is multiplier, the 4th one is tolerance and the fifth one is voltage rating.

Capacitor Color Code Table

Color Digit 1 Digit 2 Multiplier Tolerance Tolerance* Voltage
Black 0 0 1 ±20% ±2.0pF 100
Brown 1 1 10 ±1% <±0.1pF 200
Red 2 2 100 ±2% ±0.25pF 300
Orange 3 3 1000 ±3% – 400
Yellow 4 4 10000 ±4% – 500/td>
Green 5 5 100000 ±5% ±0.5pF 600
Blue 6 6 Not Used – – 700
Violet 7 7 Not Used – – 800
Grey 8 8 0.01/td> +80%,-20% – 900
White 9 9 0.1 ±10% ±1pF 1000

 

You can see the chart has two tolerance values in it. When the calculated value of capacitance is larger than 10 pF the first tolerance column should be considered. If the calculated value is less than 10 pF the second tolerance column should be taken. There is a significant difference between the two methods, so don’t miss them while decoding the capacitor.
Capacitor Value = [Digit1 Digit 2 * multiplier] ± Tolerance
Let see a small example for this,
Here we have color coded polyester capacitor. Noting the colors we can formulate the codes and finally we can find out the capacitance value.
Digit 1 Orange 3
Digit 2 Yellow 4
Multiplier White 0.1
Tolerance Red ±0.25pF
There fore Capacitor Value as per equation(1)  = 34*0.1 ± 0.25 pF = 3.4 ± 0.25 pF

Capacitor Voltage Color Code Table

Color Voltage Rating
Type J Type K Type L Type M Type N
Black 4 100 10 10
Brown 6 200 100 1.6
Red 10 300 250 4 35
Orange 15 400 40
Yellow 20 500 400 6.3>/td> 6
Green 25 600 16 15
Blue 35 700 630 20
Violet 50 800
Grey 900 25 25
White 3 1000 2.5 3
  • Type J  : Diped Tantalum Capacitors
  • Type K : Mica Capacitors
  • Type L  : Polyester/Polystyrene Capacitors
  • Type M :Electrolytic 4 Band Capacitors
  • Type N : Electrolytic 3 Band Capacitors

Number Coding

The ceramic capacitors have number coding. The important one to be noted is that usually capacitor values range is Pico farads (10-12F). Most of them have 3 numbers. The 3 numbers are having unique significance. The 1st and 2nd numbers are significant digits and 3rd one is a multiplier. Mostly the last digit signifies how many zeroes to be added after the first two digits.

The multiplier table is given below.

Third Digit Multiplier Value
0 1
1 10
2 100
3 1000
4 10000
5 100000
6 Not Used
7 Not Used
8 0.01
9 0.1

So 104K  means 10+4 zeroes in pF which is also same as 0.1uF or 100nF.Same procedure in the case of  capacitor marked as 103,102 etc.

The alphabet represents the tolerance. Here K means it is having a tolerance of  +/- 10%

Various letters are used for corresponding tolerances.

The tolerance table is given below

Code Tolerance Code Tolerance
A ±0.05pF K ±10%
B ±0.1pF L ±15%
C ±0.25pF M ±20%
D ±0.5pF N ±30%
E ±0.5% P 0 to 100%
F ±1% S -20 to 50%
G ±2% W 0 to 200%
H ±3% X -20 to 40%
J ±5% Z -20 to 80%

The only difference between the color coding and number coding is, the numbers are directly printed to represent the significant digits and the other parameters.