# Resistors

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Resistors
Resistors are electronic components that oppose the flow of current. Manufactured in various types and ranges they have a wide application to electronics.

The relationship between voltage and current in a resistor is given by Ohm's Law:

## Identification and Values

### Colour Code

When inspecting resistors, the given value is either printed on the body is can be determined from the resistor colour code.

Resistor Colour Code
Example

Red(2)Blue(6)Green(5)
=2600000
=2.6 MΩ

The first two bands are the value and the third band is a decimal multiplier (10x).

Black Brown Red Orange Yellow Green Blue Violet Grey White

0

1

2

3

4

5

6

7

8

9

The fourth band give the tolerance:

Gold Silver None

5%

10%

20%

For precision resistors, sometimes a five band colour coding is used – first three bands are the value, fourth band is the multiplier and the fifth band is the tolerance.

## Preferred Values

Resistors are manufactured and specified in a range of preferred values.

The table shows the range of preferred values:

 10 12 15 18 22 27 33 39 47 56 68 82

Note: to obtain full range, multiply table by 10X

## Circuit Arrangements

For more information on circuit arrangements and how to work these out, please see the following note:

More interesting Notes:

Steven has over twenty five years experience working on some of the largest construction projects. He has a deep technical understanding of electrical engineering and is keen to share this knowledge. About the author

myElectrical Engineering

#### View 2 Comments (old system)

1. resistor says:
8/7/2012 7:58 PM

There also exist 6 band resistors, where the 6th band often refers to the thermal coefficient. for more information on resistor color codes http://www.resistorguide.com/resistor-color-code

• Steven says:
8/8/2012 12:59 PM

Thanks for the information on the sixth band. Your site all about resistors is interesting; good luck with it.

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