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

DELTA V

Symbols

Differential voltmeter

A differential voltmeter indicates a difference between documented voltage inputs. Its reference and compared circuits must be identifiable so the indicated difference has a defined meaning.

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

A distinction that matters

A differential voltage indicator is different from a transformer differential protection function.

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.