Appendix G: Standard Values of Resistors, Capacitors, and Inductors

Abstract

Except for wire-wound/cermet/high-power/precision resistors, most common resistors do not have their resistance value printed on them, but rather have a color code representing their resistance value as illustrated in Figure G.1. Table G.1 shows the numerical value or tolerance (manufacturer's reliability rating) represented by each color. For example, the resistance value of a resistor with the four-color band of yellow-violet-red-silver is R = 10a + b × 10 m ± = 10 × 4 + 7 × 10 2 ± 10 = 4700 ± 470 Ω (G.1) and that of a resistor with the five-color band of orange-black-white-gold-gold is R = 100a + 10b + c × 10 m ± = 100 × 3 + 10 × 0 + 1 × 10 − 1 ± 5 = 30 1 ± 0 15 Ω (G.2) (cf.) Visit the web site http://xtronics.com/kits/rcode.htm for more details about the color code.