BS 1852

The British standard BS 1852^[1] and its replacement, BS EN 60062,^[2][3] comprises a colour code for fixed resistors; letter and digit code for resistance (R for ohms, K for kilohms and M for megohms) and capacitance values.

Codes

Letter code for resistance and capacitance tolerances and a date code for capacitors and resistors:

coding:

BB - 1/8 WATTS,

CB - 1/4 ″ ,

EB - 1/2 ″ ,

GB - 1/1 ″ ,

5 - ±5% tolerance,

2 - ±20% ″,

1 - ±10% ″,

Steps to find out the resistance or capacitance values:

1. 1st 2 letters gives the power dissipation capacity.
2. next 3 digits gives the resistance value.
   1. 1st 2 digits are the significant values
   2. 3rd digit is the multiplier.
3. final digit gives the tolerance.

Examples

If a resistor is coded :

• EB1041: power dissipation capacity = 1/2 watts, resistance value = 10×10^4±10% = between 9×10^4 ohms and 11×10^4 ohms.
• CB3932: power dissipation capacity = 1/4 watts, resistance value = 39×10^3±20% = between 46.8×10^3 ohms and 31.2×10^3 ohms.

Examples of resistance values
R47	0.47 ohm
4R7	4.7 ohm
470R	470 ohm
4K7	4.7 kilohm
47K	47 kilohm
47K3	47.3 kilohm
470K	470 kilohm
4M7	4.7 megohm

References

1. BS 1852:1975, IEC 60062:1974
2. BS EN 60062:1994
3. BS EN 60062:2005