There are direct numbering method and color ring method for resistance value. I don't need to tell you the direct number. The following mainly introduces the identification of color ring resistance?

At present, color ring resistors are widely used in electronic products. Its advantage is that in the process of assembly, debugging and maintenance, the color ring can be seen clearly from any angle, and the resistance value can be read out, which is convenient to use. A resistance color ring consists of four parts [excluding precision resistance]?

The first and second rings of the four color rings respectively represent the first two digits of the resistance value; The third ring represents the magnification; The fourth ring represents an error. ?

The following are some key points to master this method:

(1) Remember the numbers represented by each color of the first and second rings. Can you remember this:

Brown = 1?

Red =2,

Orange =3,

Yellow =4,

Green =5,

Blue =6,

Purple =7,

Gray =8,?

White =9,

Black =0. ?

This is a basic skill, repeat it many times, and you must remember it! ! ! ! ! ! ! ?

Do you remember what the color of the third ring stands for? Resistance range, this is the key. The specific method is:

Gold: What time is it? Ω?

Black: Dozens? Ω?

Brown: How many hundreds? Ω?

Rhett: What time is it? kω？

Oranges: Dozens? kω？

Yellow: How many hundreds? kω？

Green: What time is it? mω？

Blue: Dozens? mω？

From the order of magnitude, they can be divided into three grades, namely: gold, black and brown are ohmic; Red is an orange of 1000 euros, and yellow is an orange of 10 euros. Green is megohm, and blue is 10 megohm. This division is for the convenience of memory. ?

(3) When the second ring is black, the color of the third ring represents an integer, that is, how many, dozens or hundreds? K ω, etc. This is a special case when studying, so pay attention to it. For example, if the third ring is red, its resistance is an integer of several kω. ?

(4) Remember the error represented by the color of the fourth ring, that is, gold is 5%; Silver is10%; Colorless is 20%. ?

Here is an example:

Example 1 When the four color rings are yellow, orange, red and gold in turn, what is the range of resistance because the third ring is red?

Display, yellow and orange represent the numbers "4" and "3" respectively, and its reading is 4.3kΩ. The first ring is gold, indicating an error of 5%. ?

Example 2 When the four color rings are brown, black, orange and gold in turn, since the third ring is orange and the second ring is black, the resistance value should be several tens of kω. If the number "1" represented by brown is substituted, the reading is 10? Kω. The fourth ring is gold, with an error of 5%. ?

How to identify the order of color ring resistance?

Color ring resistance is the most common type of resistance in various electronic devices. No matter how it is installed, maintenance personnel can easily read its resistance value, which is convenient for detection and replacement. However, in practice, it is found that the arrangement order of some color ring resistors is not clear, and it is often easy to read wrong. When identifying, the following skills can be used to judge:

Skills 1:? Find the wrong color ring first, so as to arrange the color ring order. The most commonly used colors to indicate the resistance error are: gold, silver and brown, especially gold rings and silver rings, which are rarely used as the first ring of the resistance color ring, so as long as there are gold rings and silver rings in the resistance, it can basically be regarded as the last ring of the color ring resistance. ?

Tip 2:? Discrimination of whether the brown ring is an error symbol. Brownian rings are often used as error rings and effective digital rings at the same time, and often appear in the first ring and the last ring at the same time, making it difficult to identify who is the first ring. In practice, it can be judged according to the interval between the color rings: for example, for the resistance of a five-channel color ring, the interval between the fifth ring and the fourth ring is wider than the interval between the first ring and the second ring, and the arrangement order of the color rings can be judged accordingly. ?

Tip 3:? In the case that the color ring sequence cannot be determined by the color ring spacing alone, it can also be determined by the production sequence value of the resistor. For example, the color ring reading sequence of a resistor is brown, black, black, yellow and brown, and its value is:100×104Ω =1mΩ, which belongs to the normal series resistance value. If read in reverse order, it is: brown, yellow and black 0%. Obviously, the resistance values read in the latter order are not available in the production series, so the latter color ring order is wrong.