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

IEEE / ANSI

ANSI/IEEE Earth-fault current relay form

This reference locates earth-fault current relay in Autodesk's IEEE-oriented current protection relays family. The earth-fault current relay form identifies a relay whose operating quantity is current flowing to earth. It may be fed from a core-balance CT around all live conductors, from the residual connection of three phase CTs, or from a CT in the star-point earth lead, and the source changes its achievable sensitivity. The public library uses HCR1F37 for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number.

Drawing use: Schematic / SLD
Application: Metering & protection
Reference family: IEEE / ANSI / Manufacturer
Form evidence: Ground Failure Current Protection. Autodesk IEEE Symbol Preview: Current Protection Relays, block HCR1F37. Matching functional counterpart linked separately. Independently drawn educational geometry; not a certified IEEE glyph or database identifier.

A distinction that matters

An earth-fault current relay measures current to earth; an earth-fault voltage relay measures neutral displacement voltage.

Full reference

Symbols

Earth-fault current relay

The earth-fault current relay form identifies a relay whose operating quantity is current flowing to earth. It may be fed from a core-balance CT around all live conductors, from the residual connection of three phase CTs, or from a CT in the star-point earth lead, and the source changes its achievable sensitivity.

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

A distinction that matters

An earth-fault current relay measures current to earth; an earth-fault voltage relay measures neutral displacement voltage.

Full reference

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