Latest Articles

Colour code of carbon resistors

Colour code of carbon resistors

Commercially resistors of different type and values are available in the market but in electronic circuits carbon resistors are more frequently used
In carbon resistors value of resistance is indicated by four coloured bands marked on its surface as shown below in figure
The first three bands a,b.c determine the value of the resistance and fourth band d gives the tolerance of the resistance
The colour of the first and second band respectively gives the first and second significant figure of the resistance and third band c gives the power of the ten by which two significant digits are multiplied for obtaining the value of the resistance

value of different colurs for making bands in carbon resistors are given below in the table

For example in a given resistor let first strip be brown ,second strip be red and third be orange and fourth be gold then resistance of the resistor would be
12X 10³ +/- 5%