Identification of Color-coded Resistor

Resistors with color bands are a convenient way for users to determine their resistance value simply by identifying the colored bands, without the need for any measuring tools. This type of marking is commonly found on cylindrical resistors such as carbon film, metal film, metal oxide film, fuse, and wire-wound resistors. These components typically have four, five, or six color bands that represent their resistance value and other specifications.

Color-coded resistors are among the most frequently used electronic components in circuits. They feature colored bands painted on their surface to indicate their resistance value. The units commonly used include ohms (Ω), kilo-ohms (KΩ), and mega-ohms (MΩ). For reference, 1 MΩ equals 1,000 KΩ or 1,000,000 Ω.

Most color-coded resistors come in either four-band or five-band configurations, with the four-band version being more common. In a four-band resistor, the first two bands represent the significant digits, the third band indicates the multiplier, and the fourth band shows the tolerance. For five-band resistors, the first three bands are the significant digits, the fourth is the multiplier, and the fifth is the tolerance. Tolerance is usually indicated by gold (5%), silver (10%), or brown (1%). A missing band means a 20% tolerance, while green occasionally represents a 0.5% tolerance.

Identifying Four-Band Resistors

A four-band resistor uses four colored bands to show its resistance value. Starting from the left, the first band is the first digit, the second is the second digit, the third is the multiplier, and the fourth is the tolerance. If you're unsure which band is the first one, look for the fourth band, which is often gold or silver, as it's rarely another color. This method only applies to four-band resistors.

Examples:

• Red, Yellow, Brown, Gold: 24 × 10 = 240 Ω, Tolerance: 5%
• Green, Red, Yellow, Silver: 52 × 10,000 = 520 KΩ, Tolerance: 10%

Identifying Five-Band Resistors

Five-band resistors use five colored bands to represent their resistance value. From left to right, the first three bands are the significant digits, the fourth is the multiplier, and the fifth is the tolerance. For example, Red, Red, Black, Black, Brown would be interpreted as 220 × 1 = 220 Ω, with a 1% tolerance.

Identifying Six-Band Resistors

Six-band resistors are less common and are used in precision applications. The first five bands follow the same pattern as a five-band resistor, but the sixth band indicates the temperature coefficient. These resistors are typically found in high-precision electronic systems where stability over temperature is critical.

Understanding how to read these color bands is essential for anyone working with electronics, whether they are hobbyists or professionals. It allows for quick identification of component values without the need for additional testing equipment.