Color Code On Resistors

Resistors are a fundamental component in electronic circuits, controlling the flow of electrical current by offering resistance. Their bodies are often marked with a series of colored bands that represent their resistance values, tolerance, and sometimes their temperature coefficient.

Deciphering these colors is crucial for anyone working with electronics, from hobbyists to professional engineers. This article breaks down the meaning of these colors and how to interpret them effectively.

The Basics of Resistor Color Codes

What Are Resistor Color Codes?

Resistor color codes are a system of colored bands painted on the bodies of resistors. These colors are not arbitrary; each color corresponds to a specific number or value, which, when read together, indicates the resistor’s electrical resistance.

The standard color code system uses four, five, or six bands to denote resistance value, tolerance, and, in some cases, temperature coefficient.

Decoding the Colors

The most common system uses four bands:

• The first two bands represent the first two significant digits of the resistance value.
• The third band is the multiplier, indicating the power of ten to multiply the first two digits.
• The fourth band shows the tolerance, or how much the resistance can vary from its specified value.

A five-band system adds a third significant digit for more precise resistance values, while a six-band system includes a temperature coefficient band, indicating how the resistance value changes with temperature.

Color Coding Chart and Interpretation

4-Band Resistor Color Code

• First Band (First Digit)
• Second Band (Second Digit)
• Third Band (Multiplier)
• Fourth Band (Tolerance)

5-Band Resistor Color Code

• First Band (First Digit)
• Second Band (Second Digit)
• Third Band (Third Digit)
• Fourth Band (Multiplier)
• Fifth Band (Tolerance)

Color	Digit	Multiplier (Ω)	Tolerance (%)
Black	0	1
Brown	1	10	±1
Red	2	100	±2
Orange	3	1k
Yellow	4	10k
Green	5	100k	±0.5
Blue	6	1M	±0.25
Violet	7	10M	±0.1
Gray	8	100M	±0.05
White	9	1G
Gold		0.1	±5
Silver		0.01	±10

How to Read

• 4-Band Resistor: Read the first two bands for the significant figures, the third for the multiplier, and the fourth for tolerance. For example, a resistor with bands of yellow, violet, red, and gold has a resistance of 47×100 (4700 Ohms or 4.7k Ohms) with a tolerance of ±5%.
• 5-Band Resistor: Read the first three bands for the significant figures, the fourth band for the multiplier, and the fifth for tolerance. This allows for more precise resistance values, such as a resistor with bands of green, blue, black, red, and brown, which has a resistance of 560×100 (56k Ohms) with a tolerance of ±1%.

This chart and explanation should help you understand and use the resistor color coding system. Remember, the color code is read from left to right, with the tolerance band (if present) being the last band on the right.

Practical Example

Let’s take a resistor with the color bands brown, black, red, and gold. Using our chart:

• Brown (1) and Black (0) are the significant digits, making 10.
• Red indicates a multiplier of 102102 or 100.
• Therefore, the resistance value is 10 * 100 = 1000 ohms or 1kΩ.
• Gold signifies a tolerance of ±5%.

Tips for Reading Resistor Color Codes

• Read from left to right, with the tolerance band (if it’s gold or silver) on the right.
• If there’s a gap between bands, the wider gap usually indicates the direction to start reading from, with the gap on the right.
• Practice with various resistors to become familiar with quickly identifying values.

What is the rhyme for the color code of a resistor?

“Bad Beer Rots Our Young Guts But Vodka Goes Well“

This corresponds to the sequence of colors and their associated numerical values, which are:

• Bad – Black (0)
• Beer – Brown (1)
• Rots – Red (2)
• Our – Orange (3)
• Young – Yellow (4)
• Guts – Green (5)
• But – Blue (6)
• Vodka – Violet (7)
• Goes – Gray (8)
• Well – White (9)

For tolerance, gold (±5%) and silver (±10%) are often remembered separately, as they do not fit directly into the color sequence of the mnemonic.

This mnemonic is a helpful tool for quickly recalling the order of colors on a resistor, representing the resistor’s value in ohms as part of the electronic color code.

Conclusion

Understanding resistor color codes is an essential skill in electronics, allowing for quick identification and verification of component values. Reading these colors can become second nature with practice, facilitating the design, repair, or modification of electronic circuits.

As technology evolves, the basics of electronic components like resistors remain a constant foundation of knowledge for enthusiasts and professionals alike.

Frequently Asked Questions