Resistance Color Code is expressed using colored bands to easily define the resistance value and percentage tolerance of resistors.
From the link here you can access the application where you can calculate the color calculation and the resistance from the color from the resistance value.
There are many different types of resistance that can be used in both electrical and electronic circuits to control current flow or produce voltage drop in many different ways.But to do this, the actual resistance must have some kind of "resistance" value.Resistances are available in different resistance values, from the factions of an Ohm (Ω) to millions of Ohms.
Obviously, it would be impractical to have existing resistances at every possible value, such as 1Ω , 2Ω , 3Ω, 4Ω, etc., for example, because literally tens of thousands, even tens of millions of different resistances need to be present.Instead, resistors are produced as "most preferred values" with resistance values printed on their bodies in colored ink.
When the resistance value, tolerance and wattage value, resistance body, such as large power resistors, are large enough to read the pressure, they are usually printed in numbers or letters on the body of the resistance.However, when resistance is small, such as 1/4 watt of carbon or film type, these properties should be shown differently, since the print is too small to read.
To overcome this, small resistors use colored painted tapes to indicate both resistance values and tolerances with the physical size of the resistance indicating the wattage value.These colored painted tapes produce a identification system commonly known as the Resistance Color Code.
An internationally and universally accepted resistance color code scheme was developed years ago as a simple and fast way to determine the omic value of a resistance, regardless of size or condition.It consists of a series of separate colored rings or bands in spectral order, representing each digit of the resistance value.
Resistance color code marks always start from left to right, one band at a time is read, the wider width tolerance band is directed to the right and shows tolerance.By matching the color of the first band with the associated number of the color table in the digit column, the number below the first digit is determined and represents the first digit of this resistance value.
Again, we get the second digit of the resistance value by matching the color of the second band to the associated number of the color table in the digit column.Then the resistance color code is read from left to right, as shown below:
Standard Resistance Color Code Table
Resistance Color Code Table
It is necessary to calculate the different weighted positions of each color band that makes up the above resistance color code according to the following table:
Number of Colored Bands
|3 Color Band |
|4 Color Band |
|5 Color Band |
|6 Color Band |
|1 Band||1. Residence||1. Residence||1. Residence||1. Residence|
|6 Tape||–||–||–||Temperature |
Calculation of Resistance Values
Now that we understand the Resistance Color Code system, we can start the calculation process. To get the right value of resistance, we start reading from the left side, so how do we understand the left side? There are many methods in this regard, the most prominent household is generally considered the left side, or the closest digit to the cable is considered left.
ResidenceDigit, Multiplier = Color, Color x 10 Color in Ohms (Ω)
For example, suppose a resistance has the following colored markings;
Yellow Purple Red = 4 7 2 = 4 7 x 102 = 4700Ω or 4k7 Ohm
The fourth and fifth bands are used to determine the percentage tolerance of resistance.Resistance tolerance is a measure of resistance change from the specified resistance value and is a result of the production process and is expressed as "nominal" or a percentage of its preferred value.
Typical resistance tolerances for film resistors range from 1% to 10%, while carbon resistance tolerances have tolerances of up to 20%.Resistances with tolerances less than 2%, or lower tolerance resistances are called precision resistors that are more expensive.
Most five-band resistors are precision resistors with a tolerance of 1% or 2%, while most four-band resistors have tolerances of 5%, 10% and 20%.The color code used to indicate the degree of tolerance of a resistance is given as follows:
Brown = 1%, Red = 2%, Gold = 5%, Silver = 10%
If the resistance does not have a fourth tolerance band, the default tolerance will be 20%.
It is sometimes easier to remember the resistance color code using short, easily remembered sentences in the form of named phrases, rhymes, and phrases that have a separate word in the sentence to represent each of the ten colors.
The resulting reminder matches the first letter of each word that forms the color code of the resistors in order of increments of magnitude, and there are many different groups of reminders that can be used.However, these words are often meaningless, but never less effective for remembering the colors of resistance:
LIKE I CAN'T COUNT ON THE STREET
Siyah – 0
Kahverengi – 1
Kweir – 2
Tproducts – 3
Sbee – 4
Ythreshold – 5 AM
Mor – 7
Gri – 8
Beyaz – 9
British Standard (BS 1852) Code
In general, in larger power resistors, resistance color code systems are not required as the resistance value, tolerance and even the degree of power (watts) are printed on the actual body of the resistance instead of the resistance color code system.Because it is very easy to "misread" the position of the deprecation point or comma, especially when the component color is faded or dirty.An easier system has been developed for writing and printing the resistance values of individual resistors.
This system complies with the British Standard BS 1852 Standard and its replacement BS EN 60062 encoding method, the dex should be replaced by the letter "K" for bin or kilohm, and the letter "M" for millions or megaohms. Refers to the multiplier value with the letter "R" used in cases where the multiplier is less than one, and the arrival of any number after these letters means that it corresponds to the decimal place.
|BS 1852 Codes for Resistance Values|
|0.47Ω = R47 or 0R47|
|1.0Ω = 1R0|
|4.7Ω = 4R7|
|47Ω = 47R|
|470Ω = 470R or 0K47|
|1.0KΩ = 1K0|
|4.7KΩ = 4K7|
|47KΩ = 47K|
|470KΩ = 470K or 0M47|
|1MΩ = 1M0|
Sometimes, depending on the manufacturer, there is an additional letter representing the resistance tolerance value, such as 4k7 J, after the typed resistance value, and these last additional letters are given as follows:
|Tolerance Codes for Resistors (±)|
|B = 0.1%|
|C = 0.25%|
|D = 0.5%|
|F = %1|
|G = %2|
|J = 5%|
|K = 10%|
|M = 20%|
In addition, be careful not to confuse these written codes with resistance values, where K and M refer to the tolerance value, and these tolerance codes are written with or without spaces after the resistance value.
Resistance Tolerance, E-series and Preferred Values
In order to have a resistance from every possible resistance value, it is necessary to produce literally hundreds of thousands of different resistances, even if there are not millions of resistance SKs.Instead, resistors are produced in values commonly known as preferred values.
Instead of sequential resistance values of 1Ω and above, certain resistance values are available within certain tolerance limits.The tolerance of a resistance is the maximum difference between its actual value and the required value, and is usually expressed as a plus or minus percentage value.For example, a tolerance of 1kΩ ± 20% can have a maximum and minimum resistance value:
Maximum Resistance Value
1kΩ or 1000Ω + 20% = 1,200Ω
Minimum Resistance Value
1kΩ or 1000Ω – 20% = 800Ω
Then, using our example above, the maximum value of the 1kΩ ± 20% tolerance resistance can be 1200Ω and the minimum value can be 800Ω, resulting in a difference of 400Ω.
In most electrical or electronic circuits, this large 20% tolerance of the same resistance is usually not a problem, but when close tolerance resistance is specified for high-accuracy circuits such as filters, oscillators or amplifiers, etc., the correct tolerance resistance should be used. 20% tolerance resistance is usually not used to replace tolerance type 2 or %1.
The five- and six-band resistance color code is mostly associated with high-precision 1% and 2% film types, while 5% and 10% general purpose types tend to use the four-band resistance color code.Resistors have a number of tolerances, but the two most common are the E12 and E24 series.
Resistance Tolerance and E-series Table
|± 20% Tolerance E6 Series – Resistance values in Ω|
|1.0, 1.5, 2.2, 3.3, 4.7, 6.8|
|± 10% Tolerance E12 Series – Resistance values in Ω|
|1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2|
|± 5% Tolerance E24 Series – Resistance values in Ω|
|1.0, 1.1, 1.2, 1.3, 1.5, 1.6, 1.8, 2.0, 2.2, 2.4, 2.7, 3.0, |
3.3, 3.6, 3.9, 4.3, 4.7, 5.1, 5.6, 6.2, 6.8, 7.2, 8.2, 9.1
|±%1 Tolerance E96 Series – Resistance values in Ω|
|1.00, 1.02, 1.05, 1.07, 1.10, 1.13, 1.15, 1.18, 1.21, 1.24, 1.27, 1.30, 1.33, 1.37, 1.40, 1.43, 1.47, 1.50, 1.54, 1.58, 1.62, 1.65, 1.69, 1.74, 1.78, 1.82, 1.87, 1.91, 1.96, 2.00, 2.05, 2.10, 2.15, 2.21, 2.26, 2.32, 2.37, 2.43, 2.49, 2.55, 2.61, 2.67, 2.74, 2.80, 2.87, 2.94, 3.01, 3.09, 3.16, 3.24, 3.32, 3.40, 3.48, 3.57, 3.65, 3.74, 3.83, 3.92, 4.02, 4.12, 4.22, 4.32, 4.42, 4.53, 4.64, 4.75, 4.87, 4.99, 5.11, 5.23, 5.36, 5.49, 5.62, 5.76, 5.90, 6.04, 6.19, 6.34, 6.49, 6.65, 6.81, 6.98, 7.15, 7.32, 7.50, 7.68, 7.87, 8.06, 8.25, 8.45, 8.66, 8.87, 9.09, 9.31, 9.53, 9.76|
Then, using the appropriate E-series value for the percentage tolerance required for resistance, a multiplication factor can be added to it, and any omic resistance value within that series can be found.For example, the calculated value for a 10% tolerance E-12 series resistance with a preferred value of 3.3:
Value x Multiplier = Resistance
3.3 x 1 = 3.3Ω
3.3 x 10 = 33Ω
3.3 x 100 = 330Ω
3.3 x 1000 = 3.3kΩ
3.3 x 10,000 = 33kΩ
3.3 x 100.000 = 330kΩ
3.3 x 1,000,000 = 3.3MΩ
The mathematical basis for these preferred values comes from the square root value of the actual series used.For example, there are six separate resistances or steps (1.0 to 6.8) for the E6 20% series and are given as the sixth root of ten (6√ 10), so there are twelve separate resistances or steps for the E12 10% series. (1.0 to 8.2) and therefore the twelfth root of ten ( 12√ 10 ) and continues for the remaining E-series values.
The tolerance series of Preferred Values shown above is manufactured to comply with the British Standard BS 2488 and are ranges of resistance values selected to match the neighboring value of any resistance at maximum or minimum tolerance.For example, take the 5% tolerance E24 resistance series.Neighbor resistance values are 47 and 51Ω, respectively.
47Ω + 5% = 49.35Ω and 51Ω – 5% = 48.45Ω , only 0.9Ω overlap occurs.
Surface Mounting Resistance (SMD Resistance)
Surface Mounting Resistance, or SMD Resistance, are very small rectangular shaped metal oxide film resistors designed to be soldered directly to the surface of a circuit board.Surface mounting resistors usually have a ceramic substrate body on which a thick layer of metal oxide resistance is placed.
The resistance value of the resistance is controlled by increasing the desired thickness, length or type of coated film used and low tolerance resistors can be produced with high precision of up to 0.1%.There are also metal terminals or covers at both ends of the body that allow them to be soldered to direct printed circuit boards.
Surface Mounted Resistors are printed with a 3- or 4-digit numeric code similar to that used in more common axial type resistors to indicate resistance values.Standard SMD resistors are marked with a three-digit code in which the resistance value of the first two digits represents the first two digits, and the third digit is the multiplier x1, x10, x100, etc. Eg:
"103" = 10 ×1.000 ohm = 10× 103 = 10 kiloΩ
"392" = 39 × 100 ohm = 39× 102 = 3.9 kiloΩ
"563" = 56 ×1.000 ohm = 56× 103 = 56 kiloΩ
"105" = 10 × 100,000 ohms =10× 105 = 1 MegaΩ
Surface mounting resistors with a value less than 100Ω are usually written as: "390", "470", "560", and the last zero represents 10 x o multiplier, this is equal to 1. Eg:
"390" = 39× 100 = 39 × 1Ω = 39Ω or 39RΩ
"470" = 47×10 0 = 47 × 1Ω = 47Ω or 47RΩ
The resistance values below it have the letter " R " to indicate the position of the decimal point, as previously seen in the form BS1852, so that it is 4R7 = 4.7Ω.
Surface mounting resistors with the mark "000" or "0000" are zero-Ohm (0Ω) resistors, or, in other words, short-circuit connections because these components have zero resistance.
In the next content about resistors , we will examine the resistors in a series of connections and prove that the total resistance is the sum of all the resistors added together, and that the current is common for a series of circuits.