|
|
Resistors, Resistor Color Codes, Resistor Color Code Calculator
Resistors, like diodes and
relays, are another of the electronic
parts that should have a section in the installer's parts bin. They
have become a necessity for the mobile electronics installer, whether it
be for door locks, praking lights, timing circuits, remote starts, LED's,
or just to discharge a stiffening capacitor.
Resistors "resist" the flow of electrical current.
The higher the value of resistance (measured in ohms)
the lower the current will be.
Resistors are color coded. To read the color code of a common 4 band
1K ohm resistor with a 5% tolerance,
start at the opposite side of the GOLD tolerance
band and read from left to right. Write down the corresponding number from the
color chart below for the 1st color band (BROWN).
To the right of that number, write the corresponding number for the 2nd band
(BLACK) . Now multiply that number (you should have 10) by the corresponding
multiplier number of the 3rd band (RED)(100). Your answer will be 1000 or 1K.
It's that easy.
* If a resistor has 5 color bands, write the corresponding number of the 3rd
band to the right of the 2nd before you multiply by the corresponding number of
the multiplier band. If you only have 4 color bands
that include a tolerance band, ignore this column and go straight to the multiplier.
The tolerance band is usually gold or silver, but some may have none.
Because resistors are not the exact value as indicated by the color bands, manufactures
have included a tolorance color band to indicate the accuracy of the resistor.
Gold band indicates the resistor is within 5% of what is indicated.
Silver = 10% and None = 20%. Others are shown in the chart below.
The 1K ohm resistor in the example (left), may have an actual measurement
any where from 950 ohms to 1050 ohms.
If a resistor does not have a tolerance band, start from the band
closest to a lead. This will be the 1st band. If you are unable to read the color bands, then you'll have to use your multimeter.
Be sure to zero it out first!
Resistor Color Codes |
|
| Band Color |
1st Band # |
2nd Band # |
*3rd Band # |
Multiplier x |
Tolerances ± % |
| White |
9 |
9 |
9 |
1,000,000,000 |
|
|
|
|
|
|
|
|
|
