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

HSW1S92

IEC

Combined line and phase voltmeter selector

This representation identifies a selector covering phase-to-phase and phase-to-neutral voltage measurements. One selector covers both line-to-line and line-to-neutral measurements. The measurement function changes with position even though the meter and its physical terminals remain the same.

Drawing use: Schematic
Application: Metering & protection
Reference family: IEC / Manufacturer
Form evidence: Combined line and phase voltmeter selector. Autodesk IEC-60617 Symbol Preview — Measurement-selection and mechanically operated switch forms; vendor family reference, not certified IEC geometry or database identifier.

A distinction that matters

The symbol cannot replace the actual switch contact programme.

Full reference

Symbols

Current transformer

A current transformer produces a secondary current related to the current in its primary conductor. A drawing uses the CT representation to show where current is measured and which metering or protection circuit receives that measurement. It does not, by itself, specify the CT ratio, accuracy class, burden or secondary connection.

Drawing use: SLD / Schematic
Application: Metering & protection
Reference family: IEC / IEEE / ANSI

A distinction that matters

A CT measures current. A VT measures voltage. Their secondary circuits and isolation/testing arrangements are different.

Full reference

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