How to Read a 5-Band Resistor
Five-band resistors are commonly used in precision electronic circuits where greater accuracy is required. Unlike the standard four-band resistor, a 5-band resistor uses three significant digits instead of two, allowing many more resistance values to be represented. These resistors are widely used in laboratory equipment, industrial control systems, measurement instruments, communication equipment and high-quality audio electronics.
Band Functions
| Band | Purpose |
|---|---|
| Band 1 | First significant digit. |
| Band 2 | Second significant digit. |
| Band 3 | Third significant digit. |
| Band 4 | Multiplier. |
| Band 5 | Tolerance. |
Colour Code Table
| Colour | Digit | Multiplier | Tolerance |
|---|---|---|---|
| Black | 0 | ×1 | — |
| Brown | 1 | ×10 | ±1% |
| Red | 2 | ×100 | ±2% |
| Orange | 3 | ×1,000 | — |
| Yellow | 4 | ×10,000 | — |
| Green | 5 | ×100,000 | ±0.5% |
| Blue | 6 | ×1,000,000 | ±0.25% |
| Violet | 7 | ×10,000,000 | ±0.1% |
| Grey | 8 | ×100,000,000 | ±0.05% |
| White | 9 | ×1,000,000,000 | — |
| Gold | — | ×0.1 | ±5% |
| Silver | — | ×0.01 | ±10% |
How to Read a 5-Band Resistor
- Read the first three colour bands as digits.
- Read the fourth band as the multiplier.
- Read the fifth band as the tolerance.
- Multiply the three-digit number by the multiplier.
Worked Examples
Example 1
Brown Black Black Red Brown 1 0 0 ×100 ±1% 100 × 100 = 10,000 Ω = 10 kΩ ±1%
Example 2
Red Red Black Brown Brown 2 2 0 ×10 ±1% 220 × 10 = 2,200 Ω = 2.2 kΩ ±1%
Example 3
Orange Orange Black Brown Brown 3 3 0 ×10 ±1% 330 × 10 = 3,300 Ω = 3.3 kΩ ±1%
Common 5-Band Resistor Values
| Colours | Resistance |
|---|---|
| Brown • Black • Black • Brown • Brown | 1 kΩ ±1% |
| Red • Red • Black • Brown • Brown | 2.2 kΩ ±1% |
| Orange • Orange • Black • Brown • Brown | 3.3 kΩ ±1% |
| Yellow • Violet • Black • Brown • Brown | 4.7 kΩ ±1% |
| Brown • Black • Black • Red • Brown | 10 kΩ ±1% |
| Brown • Black • Black • Orange • Brown | 100 kΩ ±1% |
| Brown • Black • Black • Yellow • Brown | 1 MΩ ±1% |
Where Are 5-Band Resistors Used?
- Precision analogue circuits.
- Operational amplifiers.
- Audio preamplifiers.
- Laboratory equipment.
- Medical electronics.
- Industrial automation.
- Measurement instruments.
- Communication equipment.
- Power supply feedback circuits.
- Calibration equipment.
Reading Tips
- The tolerance band is usually separated slightly from the others.
- Most 5-band resistors have a brown (±1%) tolerance band.
- Always begin reading from the end opposite the tolerance band.
- If uncertain, verify the value using a digital multimeter.
Common Mistakes
| Mistake | Solution |
|---|---|
| Reading from the wrong end. | Locate the separated tolerance band first. |
| Ignoring the third digit. | Remember that 5-band resistors use three significant digits. |
| Confusing multiplier and tolerance bands. | The fourth band is always the multiplier. |
| Misidentifying faded colours. | Use a multimeter to confirm the value. |
Testing a 5-Band Resistor
- Read the colour bands.
- Calculate the expected resistance.
- Disconnect the circuit power.
- Measure the resistor with a digital multimeter.
- Confirm the reading is within the stated tolerance.
Key Points
- 5-band resistors use three significant digits.
- They are commonly used where higher precision is required.
- The fifth band indicates tolerance.
- Most precision resistors have ±1% tolerance.
- Learning the 5-band code makes identifying precision resistors quick and accurate.