{"schemaVersion":1,"slug":"relay-coil-with-diode-suppression","name":"Relay coil with diode suppression","kind":"symbol","abbreviation":"K DIODE","aliases":["HCR1K33","VCR1K33"],"category":"control-circuits","drawingTypes":["Schematic"],"referenceFamilies":["IEC","Manufacturer"],"summary":"A relay with diode suppression includes a diode associated with its coil to limit the transient on de-energisation.","description":["A relay with diode suppression includes a diode associated with its coil to limit the transient on de-energisation. The diode's documented connection makes control polarity important."],"readingNotes":["Verify the coil and diode polarity using the chosen relay or socket diagram.","The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation."],"drawingChecklist":["Mark coil polarity","Identify integrated suppression","Reference release-time behaviour"],"distinction":"A suppression diode protects the control circuit; it is not a contact-side arc suppressor.","facts":[{"label":"Drawing role","value":"Relay operation"},{"label":"Representation scope","value":"Functional concept; not an official standard graphic or a product footprint"},{"label":"Public vendor block reference","value":"HCR1K33, VCR1K33 (Autodesk identifiers; not IEC symbol numbers)"},{"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-relay-suppression","relevance":"Public documentation of this equipment function or named vendor variant; the illustration is independently authored and is not the source graphic."},{"sourceId":"autodesk-contacts","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-open-contact"],"artwork":"edu-relay-coil-with-diode-suppression","publishedOn":"2026-10-13","updatedOn":"2026-10-13","provenance":"independent-public-research","url":"https://eloragrid.ai/symbols/relay-coil-with-diode-suppression","illustration":{"url":"https://eloragrid.ai/library/illustrations/relay-coil-with-diode-suppression.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-relay-suppression","title":"AutoCAD Electrical: Relay suppression components","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-AF7C83A4-33F4-4144-94BE-4C5F2F448FB8.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."},{"id":"autodesk-contacts","title":"Relays and contacts: public symbol reference","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-011C62B8-9EC8-485C-B47D-B22A3F7B7574.htm","type":"cad-reference","scope":"Normally open, normally closed and changeover contacts, relay coils and latching relay variants.","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."}]}