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Capacitors

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Capacitors may be marked with 4 or more colored bands or dots. The colors encode the first and second most significant digits of the value in picofarads, and the third color the decimal multiplier. Additional bands have meanings which may vary from one type to another. Low-tolerance capacitors may begin with the first 3 (rather than 2) digits of the value. It is usually, but not always, possible to work out what scheme is used by the particular colors used. Cylindrical capacitors marked with bands may look like resistors. Color Significant digits Multiplier Tolerance % Characteristic DC working voltage V Operating temperature °C EIA/vibration Hz   Black 0 1 — — — −55 to +70 10 to 55 Brown 1 10 ±1 B 100 — — Red 2 100 ±2 C — −55 to +85 — Orange 3 1 000 — D 300 — — Yellow 4 10 000 — E — −55 to +125 10 to 2000 Green 5 100 000 ±0.5 F 500 — — Blue 6 1 000 000 — — — −55 to +150 — Violet 7 10 000 000 —...
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Resistors

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Color band system edit To distinguish left from right there is a gap between the C and D bands: In the above example, a resistor with bands of red, violet, green, and gold has first digit 2 (red; see table below), second digit 7 (violet), followed by 5 (green) zeroes: 2 700 000  ohms . Gold signifies that the tolerance is ±5%. Precision resistors may be marked with a five band system, to include three significant digits, a power of 10 multiplier, and a tolerance band. An extra-wide first band indicates a wire-wound resistor. Resistors manufactured for military use may also include a fifth band which indicates component failure rate (reliability); refer to MIL-HDBK-199 for further details. Tight tolerance resistors may have three bands for significant figures rather than two, or an additional band indicating temperature coefficient, in units of ppm/K. All coded components have at least two value bands and a multiplier; other bands are optional. The standard color code per IEC 60062:2...
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History

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Before industry standards were established, each manufacturer used their own unique system for color coding or marking their components. In the 1920s, citation needed the RMA resistor color code was developed by the Radio Manufacturers Association (RMA) as a fixed resistor coloring code marking. In 1930, the first radios with RMA color coded resistors were built. Over many decades, as the organization name changed (RMA, RTMA, RETMA, EIA) so was the name of the code. Though known most recently as EIA color code , the four name variations are found in books, magazines, catalogs, and other documents over more than 90 years. In 1952, it was standardized in IEC 62:1952 by the International Electrotechnical Commission (IEC) and since 1963 also published as EIA RS-279 . Originally only meant to be used for fixed resistors, the color code was extended to also cover capacitors with IEC 62:1968. The code was adopted by many national standards like DIN 40825 (1973), BS 1852 (1974) and IS 8186...
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