Notice how the step size increases as the value increases. The E6 series (6 values for each multiple of ten, for resistors with 20% tolerance)ġ0, 15, 22, 33, 47, 68. The standard resistor values are based on this idea and they formĪ series which follows the same pattern for every multiple of ten. To produce a sensible range of resistor values you need to increase the size of the 'step'Īs the value increases. Would be difficult to make resistors sufficiently accurate. It would be pointless to make 1000, 1010, 1020, 1030 and so on because for these valuesġ0 is a very small difference, too small to be noticeable in most circuits. That seems fine, but what happens when you reach 1000? Why is this? Imagine that you decided to make resistors everyĤ0, 50 and so on.

You may have noticed that resistors are not available with every possible value, Real resistor values (the E6 and E12 series) Value by 1000 if the letter was K, or 1000000 if the letter was M. To read the code: replace the letter with a decimal point, then multiply the Instead the letters R, K and M are used in place of the decimal point. Which avoids using a decimal point because it is easy to miss the small dot. Resistor values are often written on circuit diagrams using a code system Tolerance may be ignored for almost all circuits because precise resistor values If no fourth band is shown the tolerance is ☒0%. Resistor with a tolerance of ☑0% will have a value within 10% ofĪ special colour code is used for the fourth band tolerance: Tolerance is the precision of the resistor and it is given as a percentage. The tolerance of a resistor is shown by the fourth band of the colour code. Tolerance of resistors (fourth band of colour code)

The first and second bands represent the digits as normal. To show these small values two special colours are used for the third band: The standard colour code cannot show values of less than Is usually omitted and the value is written 270K.įind out how to make your own Resistor Colour Code Calculator This resistor has red (2), violet (7), yellow (4 zeros) and gold bands. This may be ignored for almost all circuits but further details are given The fourth band is used to shows the tolerance (precision) of the resistor,.The third band indicates the number of zeros.The second band gives the second digit.Resistor values are normally shown using coloured bands.Įach colour represents a number as shown in the table. Is quite small so resistor values are often given in Resistance is measured in ohms, the symbol for ohm is an omega Resistor values - the resistor colour code They are not damaged by heat when soldering. Resistors may be connected either way round. Resistors restrict the flow of electric current, for example a resistor is placed in series withĪ light-emitting diode (LED) to limit the current passing through the LED. Real Values (E6 & E12 series) | Power Rating

1000 ohm resistor color code