IEC 60062

IEC 60062 establishes a common language for identifying selected electrical characteristics of resistors and capacitors. The standard is intended for situations in which a full printed value is impractical, especially on small components, while manufacturers, assemblers, inspectors, and repair technicians still need to interpret the marking consistently.¹

The system covers alphanumeric and colour conventions rather than prescribing a component’s electrical design. A marking can communicate a resistance or capacitance value, a multiplier, and a tolerance; additional conventions address temperature coefficients or other characteristics where applicable. The exact marking method depends on the component family and the physical form of the part.

IEC 60062 should therefore be distinguished from standards that define preferred values, safety requirements, measurement methods, or performance tests. It tells users how specified information is represented, not whether a particular resistor or capacitor is suitable for a circuit.

The central principle is positional compression: letters, digits, colour bands, and symbols represent significant figures and powers of ten in a short sequence. For example, a three-character alphanumeric notation may use two significant figures followed by a multiplier; a letter can also serve as a decimal marker when that avoids ambiguity. Tolerance is commonly represented by a separate letter or colour convention.

Resistor colour bands are the most familiar application. Bands encode significant digits, a multiplier, and tolerance, with the reading direction established by band spacing or a distinguishing tolerance band. Capacitor markings often use digit-and-multiplier arrangements, but interpretation also depends on the unit convention and on whether the marking expresses capacitance, tolerance, rated voltage, or a temperature characteristic.

Readers should consult the applicable edition and component documentation before decoding an unfamiliar part. Similar-looking markings can have different meanings across component classes, and omitted markings are not automatically evidence of a zero value or a particular tolerance.

IEC 60062 supports interchange of component information across international supply chains by reducing dependence on manufacturer-specific shorthand. A printed code can remain legible when a component is too small for a complete value, while bills of materials and service documents can state the corresponding value and tolerance explicitly.¹

In automated assembly, the marking is only one identification layer. Production systems normally rely on part numbers, package codes, machine-readable labels, or supplier data, because surface markings may be abbreviated, obscured, orientation-dependent, or absent on very small parts. Quality control can compare the visible code with the purchasing specification and electrical measurements.

The standard also helps clarify the boundary between nominal value and tolerance. A code identifying a nominal 10-kilohm resistor does not by itself establish its power rating, voltage limit, temperature coefficient, stability, or safety classification. Those properties come from the component specification and relevant product standards.

IEC 60062 includes conventions that extend beyond the colour code commonly taught to beginners. Its subject includes marking practices for both resistors and capacitors, and the broader coding problem includes tolerance letters, decimal-point substitutions, and temperature-related designations. These details matter particularly when reading older equipment, miniature components, and parts whose markings are designed for automated or high-volume production.

Historical components can also create interpretive traps. Older national practices, house codes, faded paint, reversed band order, and printing errors may resemble an IEC notation without conforming to the current edition. A code should consequently be checked against the component’s era, package, manufacturer data, and measured value rather than decoded in isolation.

Revisions are significant because standards evolve with component technology and marking practice. The IEC catalogue is the authoritative place to identify the current edition and its status; laboratories and manufacturers should use the edition named by the applicable contract, drawing, or regulatory requirement.¹

Significant figure

A digit that contributes directly to the stated nominal value.

Multiplier

A factor, commonly a power of ten, applied to the significant figures.

Tolerance

The permitted deviation of a component’s actual value from its nominal value.

Temperature coefficient

The change in a component’s value associated with temperature, usually expressed relative to temperature change.

Preferred value

A standardized series of nominal component values; it is distinct from the marking code used to represent a value.