Technical Education Department

The Harris-Tech Zone

 

Resistors

Resistors are passive components that restrict current flow. They are used in virtually all electronic circuits. Resistor categories include foil, thin film, thick film, metal oxide film, carbon film, and wirewound.

 

Variable Resistor:

A resistor with a sliding contact that permits changing the resistance value.

 

Electronic Color Codes: Are used on electronic components, such as resistors, to indicate values or ratings.

 

Resistor Example:

Resistor Example

 

Band A is first significant figure of resistance value in ohms

Band B is the second significant figure

Band C is the decimal multiplier

Band D if present, indicates tolerance of value in percent (no color means 20%)

 

Electronic Color Codes Color Code Number Percents
Black 0 10^0
Brown 1 10^1 1%
Red 2 10^2 2%
Orange 3 10^3 3%
Yellow 4 10^4 4%
Green 5 10^5
Blue 6 10^6
Violet 7 10^7
Gray 8 10^8
White 9 10^9
Gold 0.1 5%
Silver 0.01 10%
No color 20%

Resistors are measured in ohm, so yellow violet red brown means 4700 ohms, 1% tolerance.