Side-by-side reference

Understand the difference.

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

First referenceCompare with

CB TH

IEEE / ANSI

ANSI/IEEE thermal circuit breaker symbol

The thermal breaker form adds a temperature-responsive protection concept to the circuit-interruption path. Reading it requires both the overload characteristic and the device's short-circuit rating; the small protection modifier is not a complete time-current curve.

Drawing use: SLD / Schematic
Application: Power distribution
Reference family: IEEE / ANSI / Manufacturer
Form evidence: Autodesk IEEE-oriented 1 Pole Circuit Breakers functional form. Autodesk explicitly publishes this block under IEEE Symbol Preview. The counterpart is the matching functional concept; no equivalence of every detailed standard graphic is asserted.

A distinction that matters

A thermal qualifier describes protection response, while a trip-contact symbol describes a separate control connection.

Full reference

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 reference

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