Resistors and Capacitors are types of passive electronic components. The basic unit of resistance is the ohm (Ω) and capacitance is Farad.

Standard base resistor values are given in the following tables for the most commonly used tolerances (1%, 2%, 5%, 10%), along with typically available resistance ranges.

In 1952 the IEC (International Electrotechnical Commission) decided to define the resistance and tolerance values into a norm, to ease the mass manufacturing of resistors. These are referred to as preferred values or E-series, and they are published in standard IEC 60063:1963. These standard values are also valid for other components like capacitors, inductors and Zener diodes. The preferred values for resistors were established in 1952, but the concept of the geometric series was already introduced by army engineer Renard in the 1870s. Continue reading Standard Resistor Values →