If you are stepping in the world of Electronics ,you need to have knowledge of reading Components value through their Codes.One such Coding is used in Resistor that is “Colour Coding “.
This System was developed by Radio Manufactures Association to Read the Value of Resistance from the strip of colours Printed on it. This system carries a advantage that if we are not having multimeter or any kind of meter than we can still find the value of Resistance. As every thing Carries Adavantage and disadvantages in parrallel, the problem with it is that when the component is overheated, it becomes difficult to Read the value of Resistance. Although it is minute issue which can be ignored.
The Resistors which we people commonly use come with 4 Colours Printed on it, Although there are various kind of Resistors which come with 5 or 6 colours Printed on it. There is Separate method to Calculate the Resistance for Each type of Resistor. I will be Dealing with all of those Step by Step.
4 Band Colour Code Resistor
This is the Resistor with Band of 4 Colours. For Calculating the Resistance of the Resistor You need to Look at the Chart First and then Follow the Below Mentioned Procedure:
- See the First Colour and Write the Digit Corresponding to that Colour.
- Now, See the Colour Second the Colour and write the digit Corresponding to that colour.
- These digits form a no and write that No aside.
- For third colour, write Corresponding to it.
- Now Multiply the No formed after the 3rd Step with digit formed after4th Step.
- Congrats! You have got the Resistance.
- The fourth colour represents the Tolerance value which means how much you resistor can go beyond or below of the theoretical value.
Now Lets take an Example:
Suppose the Resistor has Colours like ”Black Brown Red Silver”.
Now Corresponding to Black: – 0
For Colour Brown: – 1
Digit Formed is: 10 ( Ten)
For Red Colour Multiplier is 10^2 = 100 (Hundred)
So theoretical Value is: 10*100 = 1000 ohms ( Thousand )
And for Tolerance of Silver Colour it is: 10%
Now the Complete Answer is: 1000 ± 10%
You Might be Wondering that you have to carry the List of all thes with you every Time. But you can Remember this all by ”Black Brown Rodes Of Your Gate Became Very Good When Given Silver Colour”.
5 Band Colour Code Resistor
You might not find 5 Band Resistor in daily Use but they exist. These are used in Military or for High Accuracy Purposes. If you Know how to find the Resistance of the 4 Band Resistor then it is easy for you. For military Purposes the Fifth Band represents the Component Failure Rate.
Let us consider the color code for the resistors with the bands ”YELLOW-VIOLET-BLACK-BROWN-GREY“. Yellow corresponds to the value ‘4’ in the color chart. Violet represents ‘7’ and Black represents the value ‘0’. Brown represents the multiplier ‘10’. Thus the value of the resistance to the corresponding color code is 470*10 = 4700 ohms or 4.7 kilo ohm with the tolerance band being Grey which represents a tolerance of +/- 0.05%.
6 Band Resistor Colour Coding
The 6 band in these Resistor Represents the Change in their Resistance with Respect to Temperature that is what we call Temperature Coefficient. We can consider the same color code used for the 5-band, with an additional temperature coefficient band with a blue color. This shows that the resistor has a value of 4.7 kilo ohms, with tolerance +/- 0.05% and with a temperature coefficient of 10 ppm/K.