Chart

Allowable deviation (%) ±10±5—±1±2—±0.5±0.25±0.1±0.05—±20 temperature relationship/(×10 /°C)—1005015
25—105—1—
In addition, there is a resistor with only one black color ring in the middle, and its resistance is zero.

Identification point

(1) Remember the number represented by each color of the first and second rings. Can be remembered like this: brown 1, red 2, orange 3, yellow 4, green 5, blue 6, purple 7, gray 8, white 9, black 0. This way you can read it together and remember it a few times.

It is the key to quick knowledge to remember the range of resistance values ​​represented by the third ring color. specifically is:

Gold: What time is Ω?
Black: dozens of ohms
Brown: a few hundred tens of ohms
Red: What time is a few kΩ
Orange: tens of kΩ
Yellow: a few hundred tens of kΩ
Green: What time is MΩ?
Blue: tens of MΩ

(2) From the order of magnitude, they can be divided into three major grades, namely: gold, black, and brown are ohmic; red, orange, and yellow are thousands of ohms; green and blue are It is a mega class. This is to divide it for easy memory.

(3) When the second ring is black, the color of the third ring represents an integer, that is, several, tens, hundreds of kΩ, etc. This is a special case when reading, so be careful. For example, if the third ring is red, its resistance is a few kΩ.

(The fourth ring of the 4-ring resistance of the multiple or the fourth ring of the 5-ring resistance is a few increments after the effective number. If it is a negative number, it is a few, and the decimal point of the significant digit is shifted to the left by a few digits.)

(4) Remember the error represented by the color of the fourth ring, namely: gold is 5%; silver is 10%; colorless is 20%.

for example

Example 1 When the four color rings are yellow, orange, red, and gold, the third ring is red, and the resistance range is a few kΩ. The number represented by yellow and orange is "4" and " 3" substitution, then its reading is 4.3 kΩ. The fourth ring is gold and the error is 5%.

Example 2 When the four color rings are brown, black, orange, and gold, the third ring is orange, the second ring is black, and the resistance should be tens of kΩ. The number represented by brown is "1". Substitute, the reading is 10 kΩ. The fourth ring is gold with an error of 5%.

In some cases where it is not easy to distinguish, you can also compare the colors of the two starting ends, because the first part of the calculation, the first color, will not be gold, silver or black. If these three colors are near the edge, you need to calculate it in reverse.

There are two ways to color the color ring resistance. One is to use the 4-color ring and the other is to use the 5-color ring. The difference between the two is that the first two digits of the four color ring represent the effective number of the resistor, and the five color ring resistors use the first three digits to indicate the effective number of the resistor, and the second digit of the reciprocal of the two represents the effective number of the resistor. The multiplier, the last bit indicates the error of the resistor.

For the 4-color ring resistance, the resistance calculation method is:

Resistance = (1st color circle value * 10 + 2nd color ring value) * The 3rd color ring represents the multiplier

For the 5-color ring resistance, the resistance calculation method is:

Resistance = (1st color circle value * 100 + 2nd color ring value * 10 + 3rd color ring value) * The 4th color ring represents the multiplier

Example 1: The color identification of a 4-color ring resistor is as follows:

The nominal resistance of the resistor = 26 * 100 = 260,000,000 Ω = 260 MΩ, error range ± 5%

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