Standard color codes

Resistor Color Code Chart

A handy reference perfect for students and anyone learning electronics. Capacitor Identification Codes There are no international agreements in place to standardise capacitor identification. Most plastic film types (Figure1) have printed values and are normally in microfarads or if the symbol is n, nanofarads. Working voltage is easily identified. Tolerances are upper case letters: M = 20%, K = 10%, J = 5%, H = 2.5% and F = ± 1pF. Figure 1 A more difficult scheme is shown in Figure 2 with examples. The unit is picofarads and the third number is a multiplier. A capacitor coded 474K63 means 47 × 10000 pF which is equivalent to 470000 pF or 0.47 microfarads. K indicates 10% tolerance. 50, 63 and 100 are working volts. Figure 2 Ceramic disk capacitors have many marking schemes. Capacitance, tolerance, working voltage and temperature coefficient may be found. See Figure 3. Capacitance values are given as number without any identification as to units. (uF, nF, pF) Whole numbers usually indicate pF and decimal numbers such as 0.1 or 0.47 are microfarads. Odd looking numbers such as 473 is the previously explained system and means 47 nF. Figure 3 Figure 4 shows some other miscelaneous schemes. Figure 4

STANDARD WIRING COLOR CODES

Electronic applications (as established by the Electronic Industries Association – EIA):
Insulation Color . . . . . . .Circuit type
Black . . . . . . . . . . . . . . .Chassis grounds, returns, primary leads
Blue . . . . . . . . . . . . . . . .Plate leads, transistor collectors, FET drain
Brown . . . . . . . . . . . . . .Filaments, plate start lead
Gray . . . . . . . . . . . . . . . .AC main power leads
Green . . . . . . . . . . . . . . .Transistor base, finish grid, diodes, FET gate
Orange . . . . . . . . . . . . . .Transistor base 2, screen grid
Red . . . . . . . . . . . . . . . .B plus dc power supply
Violet . . . . . . . . . . . . . . .Power supply minus
White . . . . . . . . . . . . . . .B – C minus of bias supply, AVC – AGC return
Yellow . . . . . . . . . . . . . .Emitters-cathode and transistor, FET source

Stereo Audio Channels

Insulation Color . . . . . . .Circuit type
White . . . . . . . . . . . . . . .Left channel high side
Blue . . . . . . . . . . . . . . . .Left channel low side
Red . . . . . . . . . . . . . . . .Right channel high side
Green . . . . . . . . . . . . . . .Right channel low side

AF Transformers (audio)

Insulation Color . . . . . . .Circuit type
Black . . . . . . . . . . . . . . .Ground line
Blue . . . . . . . . . . . . . . . .Plate, collector, or drain lead. End of primary winding.
Brown . . . . . . . . . . . . . .Start primary loop. Opposite to blue lead.
Green . . . . . . . . . . . . . . .High side, end secondary loop.
Red . . . . . . . . . . . . . . . .B plus, center tap push - pull loop.
Yellow . . . . . . . . . . . . . .Secondary center tap.

IF Transformers (Intermediate Frequency)

Insulation Color . . . . . . .Circuit type
Blue . . . . . . . . . . . . . . . .Primary high side of plate, collector, or drain lead.
Green . . . . . . . . . . . . . . .Secondary high side for output.
Red . . . . . . . . . . . . . . . .Low side of primary returning B plus.
Violet . . . . . . . . . . . . . . .Secondary outputs.
White . . . . . . . . . . . . . . .Secondary low side.

Posted in: Complete Reference,Tips