Resistor Color Code

In this era resistor color code reading can be very easy if you know how to use a multi-meter.  However if you are in an attic or anywhere without your meter there is a way to read an electrical resistor value by the bands and colors.  the following saying will help you remember the resistor color code:

Bad Boys Ravish Only Young Girls But Violet Gives Willingly.

Now use the first leter of each word in the setence above to associate a number value.

(0) Black   

(1) Brown  

(2) Red      

(3) Orange 

(4) Yellow

(5) Green   

(6) Blue     

(7) Violet  

(8) Grey     

(9) White  

Resistor Color Code

First find the tolerance band, it will typically be gold ( 5%) and sometimes silver (10%).

Starting from the other end of the resistor, identify the first band - write down the number associated with that color. Example: if it is Blue then the # is 6.

Now note the second color, Example: if it is Red then the # is 2. (you should have '62' so far.)

Now note the third or 'multiplier' band and write down that as the number of zeros. Example: if it is also Red then the # would be 2.

So far you should have '6200' or '6,200'. If the 'multiplier exponent' band is Black (for zero) don't write any zeros down.

If the 'multiplier exponent' band is Gold move the decimal point one to the left. If the 'multiplier exponent' band is Silver move the decimal point two places to the left. If the resistor has one more band past the tolerance band it is a quality band.

Read the number as the '% Failure rate per 1000 hour' This is rated assuming full wattage being applied to the resistors. (To get better failure rates, resistors are typically specified to have twice the needed wattage dissipation that the circuit produces). Some resistors use this band for temco information. 1% resistors have three bands to read digits to the left of the multiplier. They have a different temperature coefficient in order to provide the 1% tolerance.

At 1% the temperature coefficient starts to become an important factor. at +/-200 ppm a change in temperature of 25 Deg C causes a value change of up to 1%