{"schemaVersion":1,"slug":"on-delay-normally-closed-contact","name":"On-delay normally-closed contact","kind":"symbol","abbreviation":"TON NC","aliases":[],"category":"control-circuits","drawingTypes":["Schematic"],"referenceFamilies":["IEC","Manufacturer"],"summary":"An on-delay NC contact opens after the associated timing condition has persisted for its documented interval.","description":["An on-delay NC contact opens after the associated timing condition has persisted for its documented interval. Its unoperated closed state is read separately from the timing annotation."],"readingNotes":["Trace what happens to the downstream permissive while the delay is running.","The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation."],"drawingChecklist":["Match timing device","Label delayed opening","State contact terminal numbers"],"distinction":"An on-delay NC contact is not an off-delay NO contact even if a sequence produces similar output timing.","facts":[{"label":"Drawing role","value":"Timed operation"},{"label":"Representation scope","value":"Functional concept; not an official standard graphic or a product footprint"},{"label":"Identifier status","value":"The short label is a functional lookup label, not an assigned IEC or IEEE symbol number. Any separately listed Autodesk code is a verified vendor block name."}],"references":[{"sourceId":"pub-symbol-timers","relevance":"Public documentation of this equipment function or named vendor variant; the illustration is independently authored and is not the source graphic."}],"related":["relay-coil","normally-closed-contact"],"artwork":"edu-on-delay-normally-closed-contact","publishedOn":"2026-10-13","updatedOn":"2026-10-13","provenance":"independent-public-research","url":"https://eloragrid.ai/symbols/on-delay-normally-closed-contact","illustration":{"url":"https://eloragrid.ai/library/illustrations/on-delay-normally-closed-contact.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pub-symbol-timers","title":"AutoCAD Electrical: Time-delay relays","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-DA927086-EEAF-48CB-B9B1-634A4B48C8C7.htm","type":"cad-reference","scope":"Public vendor catalogue naming and functional variants. Vendor block names are not IEC identifiers. Linked for reference; no graphics or CAD files are redistributed.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Public documentation of this equipment function or named vendor variant; the illustration is independently authored and is not the source graphic."}]}