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 TH

Symbols

Thermal circuit breaker

A thermal circuit breaker uses a temperature-responsive trip mechanism to detect sustained overload. Thermal operation and short-circuit interruption capability are separate aspects of the selected device.

Drawing use

SLD / Schematic

Application

Power distribution

Reference family

IEC / Manufacturer

A distinction that matters

Thermal tripping does not imply the same instantaneous response as magnetic tripping.

Full referenceAdd to legend

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

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