ResistorsResistors Resistors can be either fixed Resistors can be either fixed

or variable in valueor variable in value Fixed resistorsFixed resistors come in a come in a

variety of different shapes, variety of different shapes, sizes and formssizes and forms

Axial lead resistors have the Axial lead resistors have the value of resistance printed on value of resistance printed on them or as a colour codethem or as a colour code

Surface mount resistors have Surface mount resistors have a numerical code indicating a a numerical code indicating a valuevalue

All resistors have a tolerance All resistors have a tolerance valuevalue

ResistorsResistors Variable resistorsVariable resistors

are called are called potentiometerspotentiometers

There is a fixed There is a fixed value of resistance value of resistance between two between two terminalsterminals

The moving part of The moving part of the potentiometer the potentiometer is called the wiperis called the wiper

ResistorsResistors Four band resistor Four band resistor

colour codecolour code 1st band provides the 1st band provides the

first digit of the codefirst digit of the code 2nd band provides the 2nd band provides the

second digit of the second digit of the codecode

3rd band is the 3rd band is the multipliermultiplier

4th band indicates the 4th band indicates the tolerance valuetolerance value

ResistorsResistorsResistor colour code calculationResistor colour code calculation

The first band red has a value The first band red has a value of 2of 2

The second band purple has a The second band purple has a value of 7value of 7

The third band has a The third band has a multiplier of x 10multiplier of x 10

The last band indicates a The last band indicates a tolerance value of tolerance value of +/-5%+/-5%

Resistance value is 270Ω +/-Resistance value is 270Ω +/-5%5%

2

7

x10

+/-5%