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

IEC

Smoke detector plan symbol

Point smoke detectors are drawn on fire alarm layouts as a square or circle with a smoke mark inside, such as wavy lines or the letter S, at their ceiling position. Each symbol is usually tagged with its loop and device address so the plan doubles as the commissioning record.

Drawing use: GA
Application: Installation & communications
Reference family: IEC
Form evidence: Smoke detector. IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier.

A distinction that matters

A heat detector responds to temperature, not smoke; it uses a different internal mark.

Full reference

IEC

Fixed-temperature heat detector plan symbol

Fixed-temperature heat detectors alarm when the surrounding air reaches a set point, commonly around 57 to 90 degrees Celsius depending on class. Plans draw the detector box with a temperature mark or the letter H, often with a class tag.

Drawing use: GA
Application: Installation & communications
Reference family: IEC
Form evidence: Heat detector, fixed temperature. IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier.

A distinction that matters

A rate-of-rise detector responds to a fast temperature increase; this one only to an absolute threshold.

Full reference

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