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

SEL 4 HOLD Four-position maintained selector: original educational illustration

Symbols

Four-position maintained selector

A four-position maintained selector provides four stable operating choices. Each contact's state across those choices is recorded in a schedule instead of trying to express the complete logic in one contact outline.

Drawing use: Schematic
Application: Control circuits
Reference family: IEC / Manufacturer

A distinction that matters

Four positions do not imply four independent contact poles.

Full reference

Symbols

Selector switch

A selector switch provides a choice between operating positions such as local and remote or manual and automatic. Its contacts may be shown separately from the operator symbol. The contact truth table or switching schedule defines which contacts operate in each position.

Drawing use: Schematic
Application: Control circuits
Reference family: IEC / IEEE / ANSI

A distinction that matters

A changeover contact describes connections; a selector switch also includes an operator and its position behaviour.

Full reference

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