Single-line busbar symbol

A heavy line carrying connections.

Also known as: Busbar symbol, Distribution bus symbol

Engineering & technicalStandard profile

Meanings

The single-line diagram symbol for a busbar, the common conductor from which circuits are taken.

Officially standardisedVerified fact
Marks a busbar, the common conductor from which circuits are taken, on a single-line diagram.
Contexts: Technical drawing
Officially standardisedVerified fact
Anchors the whole diagram, so a single-line drawing is organised around its busbars in the way a services plan is organised around the building.
Contexts: Technical drawing

A heavy horizontal line drawn across the diagram with connections dropping from it at intervals.

IdentityHigh confidence: High confidence because the identity is defined by a current official standard, but only a single source has been found so far.
Historical originLow confidence: Low confidence because the historical origin is documented in encyclopedic references, but only a single source has been found so far, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is defined by a current official standard, but only a single source has been found so far.
Visual matchModerate confidence: Moderate confidence because the visual match is documented in encyclopedic references, but only a single source has been found so far.

IEC 60617, Graphical symbols for diagrams, single-line representation
International Electrotechnical Commission · retrieved 2026-08-25
The international standard for electrical diagram symbols, including the single-line forms used on power distribution drawings. Cited for a symbol's identity and meaning; the standard's own drawings are not reproduced and no record is an installation instruction.

Last reviewed 2026-08-25

Meanings

The single-line diagram symbol for a busbar, the common conductor from which circuits are taken.

Officially standardisedVerified fact

Marks a busbar, the common conductor from which circuits are taken, on a single-line diagram.

Officially standardisedVerified fact

Anchors the whole diagram, so a single-line drawing is organised around its busbars in the way a services plan is organised around the building.

Confidence

IdentityHigh confidence: High confidence because the identity is defined by a current official standard, but only a single source has been found so far.
Historical originLow confidence: Low confidence because the historical origin is documented in encyclopedic references, but only a single source has been found so far, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is defined by a current official standard, but only a single source has been found so far.
Visual matchModerate confidence: Moderate confidence because the visual match is documented in encyclopedic references, but only a single source has been found so far.

Sources

IEC 60617, Graphical symbols for diagrams, single-line representation
International Electrotechnical Commission · retrieved 2026-08-25
The international standard for electrical diagram symbols, including the single-line forms used on power distribution drawings. Cited for a symbol's identity and meaning; the standard's own drawings are not reproduced and no record is an installation instruction.

Last reviewed 2026-08-25