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

SSW UNI

Symbols

Unidirectional semiconductor power switch

A unidirectional semiconductor switch has a specified direction for its power conduction or control behaviour. The functional direction must be identified so reversing a schematic orientation does not reverse the intended meaning.

Drawing use: SLD / Schematic
Application: Power distribution
Reference family: IEC / Manufacturer

A distinction that matters

Unidirectional operation concerns the circuit path; it does not describe the direction of all system power flows.

Full reference

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 reference

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