How to read Resistor Color Codes
First the code
Black  Brown  Red  Orange  Yellow  Green  Blue  Violet  Grey  White 
0  1  2  3  4  5  6  7  8  9 
The mnemonic
Bad Boys Ravish Only Young Girls But Violet Gives Willingly PC_fascists
Black is also easy to remember as zero because of the nothingness common to both.
(Please don't add or change the mnemonic  it will only get reverted admin)
How to read the code

 First find the tolerance band, it will typically be gold ( 5%) and sometimes silver (10%).
 Starting from the other end, identify the first band  write down the number associated with that color; in this case Blue is 6.
 Now 'read' the next color, here it is red so write down a '2' next to the six. (you should have '62' so far.)
 Now read the third or 'multiplier exponent' band and write down that as the number of zeros.
 In this example it is two so we get '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%

BS 1852 Coding for resistor values
BS 1852(British Standard 1852). The letter R is used for Ohms and K for Kohms M for Megohms and placed where the decimal point would go.
At the end is a letter that represents tolerance Where M=20%, K=10%, J=5%, G=2%, and F=1% D=.5% C=.25 B=.1%
BS 1852 coding examples 
R33  0.33 ohms 
2R2  2.2 ohms 
470R  470 Ohms 
1K2  1.2K ohms 
22K  22K ohms 
22K2  22.2K ohms 
4M7  4.7M ohms 
5K6G  5.6K ohms 2% 
33KK  33k Ohms 10% 
47K3F  47.3 K Ohms 1% 
Common surface mount coding
The third or forth digit is the multiplier
Thus 103 is a 10K resistor
475 is a 4.7M resistor
Measure resistors with Volt Ohm meter.
We now have a program that calculates the minimum error on resistor dividers of up to 4 values.
3 comments:
brod, pwede bang maglagay ka ng java script na automatic na nag ccalculate ng value ng resistor? sana bukas meron na!
brod, pwede bang maglagay ka ng java script na automatic na nag ccalculate ng value ng resistor? sana bukas meron na!
meron na bro dun sa page right side link lang yun..
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