Understand the difference.

Compare the meaning, drawing context and source references of two entries. A similar graphic or shared abbreviation does not establish equivalence.

CB

Symbols

Circuit breaker

A circuit-breaker representation identifies a device capable of interrupting its circuit under the operating conditions for which it is rated. The drawing should connect that device to its equipment identification, protection arrangement and control information. The graphical mark alone does not establish the current rating, breaking capacity or trip settings.

Drawing use

SLD / Schematic

Application

Power distribution

Reference family

IEC / IEEE / ANSI

A distinction that matters

A disconnector provides isolation; it is not automatically a fault-interrupting circuit breaker. Check published device capabilities.

Full referenceAdd to legend

Isolator

Symbols

Disconnector

A disconnector, often called an isolator, provides an isolation function in an electrical circuit. Its representation should be read with the drawing legend and the selected device specification. Do not infer load-breaking or fault-interruption capability simply because a drawing contains a switch-like mark.

Drawing use

SLD / Schematic

Application

Power distribution

Reference family

IEC / IEEE / ANSI

A distinction that matters

A load-break switch has a specified load-switching capability. A disconnector designation alone does not establish that capability.

Full referenceAdd to legend

Original educational previews. Follow the source references on each full entry for the appropriate standard or selected product.