Understand the difference.

Compare the meaning, drawing context and source references of two entries. A similar graphic or shared abbreviation does not establish equivalence.

TOFF NO

IEEE / ANSI

ANSI/IEEE off-delay normally-open contact symbol

The off-delay NO contact form identifies instant closing on the documented operation and delayed opening on release. This sequence is distinct from merely marking a contact as normally open, and auxiliary-supply behaviour must be checked separately.

Drawing use

Schematic

Application

Control circuits

Reference family

IEEE / ANSI / Manufacturer

Form evidence

Autodesk IEEE-oriented Time Delay Relays functional form. Autodesk explicitly publishes this block under IEEE Symbol Preview. The counterpart is the matching functional concept; no equivalence of every detailed standard graphic is asserted.

A distinction that matters

Off-delay NO output is not equivalent to an on-delay NC output under every operating sequence.

Full referenceAdd to legend

TOFF NO

Symbols

Off-delay normally-open contact

An off-delay NO contact retains the documented operated state for an interval after the timer trigger is removed. The actual timer timing chart establishes the switching sequence.

Drawing use

Schematic

Application

Control circuits

Reference family

IEC / Manufacturer

A distinction that matters

Off-delay release requires a stated sequence; the NO label alone only identifies the reference contact state.

Full referenceAdd to legend

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