The fourth band represents the multiplier. The fifth band represents the tolerance. In a six-band resistor, the first five bands have the same representation as a five-band resistor followed by one extra sixth band that represents the temperature coefficient of resistance TCR.
Tolerance is the percentage of error between the actual measured resistive value and the stated value. This is due to the manufacturing process and it is expressed as a percentage of its preferred value.
To calculate the resistance value, you need to group the values of the significant digits bands — i. Then you need to multiply that value by the multiplier to get the resistance value of the resistor.
Let's take for example a four-band resistor with the following band colors: Violet Green Yellow Gold. Since it is a four-band resistor, the first two bands violet and green will indicate the significant digits which are, according to the table above; A zero-ohm resistor is a resistor having a single black band.
Its resistance is approximately zero and it is used to connect two traces on a printed circuit board PCB. Is it used in automated PCB assembly where using the same equipment used to mount other resistors is easier than using a separate machine to install a wire jumper.
Resistors manufactured for military use, may include an additional band indicating the failure rate. Generally, the larger the resistor package, the more power it can dissipate. Resistors of different power ratings are produced, most commonly from 0. Carbon resistors are commonly produced in power ratings of 0. Although it is possible to produce resistors of any value, it is more useful to make a limited number of components, especially considering that any manufactured resistor is subject to a certain tolerance.
More precision resistor's costs are much higher than their less precise counterparts. Common logic dictates to choose a logarithmic scale of values so that all values are equally spaced on a logarithmic scale and match the tolerance of the range. These values are called preferred values and are standardized as E series of preferred numbers, which are used not only for resistors, but also for capacitors, inductors, and Zener diodes.
Note that the E3 series is obsolete and is almost not used anymore. Large resistors, as shown in the picture, are usually marked with numbers and letters and their reading is easy. However, the value cannot be easily printed even using modern printing technology on small resistors and other electronic components , especially if they are cylindrical.
Therefore, during the past years color bands were used for marking components. The electronic color code for this purpose was introduced in early Color codes are used not only for resistors but also for capacitors, diodes, inductors, and other electronic components.
Up to six color bands are used for resistors. The most common is a four-band color code, in which the first and second bands represent the first and second significant digit of the resistance value, the third band is the decimal multiplier and the fourth band indicates the tolerance. There is a small, sometimes poorly distinguishable gap between the third and fourth band that helps distinguish the left and right side of the symmetrical component.
Their bands mean digit, digit, multiplier. The picture above represents the color marking principle. Bands are read from left to right. They are usually grouped together close to the left end. If there is a visible gap between the last color band and other bands, then it shows the right side of the resistor.
Also, silver or gold bands if any are always on the right side. When you determined the value from the color bands, compare it to the preferred value charts. If it is not there, then try to read from another end. Note that in this calculator color marking is made according to the international standard IEC Numerical values are printed on the surface mount resistors SMT — surface-mount technology or SMD — surface-mount device of larger sizes and on larger axial-lead resistors. Because the space for marking is very small, it is sometimes not easy to read and understand the resistor value.
The marking is mostly used for servicing because during production the resistors are fed into the surface mounting machines in tapes that are suitably marked. Many, especially small SMD resistors are not marked at all and once they are dropped from tapes, the only way to find their resistance is measurement.
Several systems are used for marking: three or four digits, two digits with a letter, three digits with a letter, the RKM code, and other systems. If you see only three digits, they represent the significant figures and the third is a multiplier. The four-digit system is used for high-tolerance resistors, for example for E96 or E series resistors. For smaller resistors, another system can be used.
For example, for E96 series two digits plus one letter is used. This system can save one character comparing to the four-digit system.
That is because E96 contains less than values, which can be represented by two numbers if they are numbered sequentially, that is 01 — , 02 — , 03 — , etc.
A letter represents the multiplier. Note that manufacturers often use their own systems. Therefore, the best way to determine the resistance is always measuring with a multimeter. Google will use this information for the purpose of evaluating your use of the website, compiling reports on website activity for website operators and providing other services relating to website activity and internet usage. Google may also transfer this information to third parties where required to do so by law, or where such third parties process the information on Google's behalf.
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Switch to 5 band. What are resistor color codes used for?
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