How does a digital multimeter measure the good and bad of resistance
(1) First, measure the resistance of the resistance, if it is infinite, the resistance is internally broken. Then calculate the resistance value through the color ring on the resistance (the one that is marked directly can be read directly), and compare it with the measured value. If the error is small (should be less than the allowable error marked on the resistance), the resistance is normal. If the error is large, the resistor is damaged and cannot be used.
(2) black, brown, red, orange, yellow, green, blue, purple, gray, white, gold, silver
0, 1, .2, .3, 4, .5, 6, .7, 8, .9, . 5%, 10%
The penultimate ring indicates the number of zeros. The last digit represents the error.
There is a clever formula for this rule: brown, red, two oranges are three, four yellows, five greens, six blues, seven purples, eight grays, nine pairs of whites, blacks are zeros, and gold, five silvers, and ten errors.
For example, red, yellow, brown, gold means 240 euros.
Color ring resistance is divided into four rings and five rings, usually four rings are used.
The penultimate ring can be gold (representing ×0.1) and silver (representing ×0.01), and the last ring error can be colorless (20%).
The five-ring resistors are precision resistors, the first three rings are numerical values, and the last ring is the error color ring, usually gold, silver and brown. The error of gold is 5%, the error of silver is 10%, and the error of brown is 1%, the error of colorless is 20%, and occasionally there are errors represented by green, and the error of green is 0.5%. Precision resistors are usually used in military, aerospace and other aspects.
The color ring is actually a standard set in the early days to help people distinguish different resistance values. Now it is still widely used, such as household appliances, electronic instruments, and electronic equipment.
However, due to the relatively large color ring resistance, it is not suitable for modern highly integrated performance requirements.
