{"schemaVersion":1,"slug":"star-star-transformer","name":"Star-star transformer","kind":"symbol","abbreviation":"TX Y-Y","aliases":["HXF1T7","VXF1T7"],"category":"power-distribution","drawingTypes":["SLD","Schematic"],"referenceFamilies":["IEC","Manufacturer"],"summary":"A star-star transformer has star-connected windings on both sides.","description":["A star-star transformer has star-connected windings on both sides. Neutral accessibility and system earthing must be shown independently for each winding."],"readingNotes":["Check whether one, both or neither star point is brought to terminals.","The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation."],"drawingChecklist":["Identify neutral terminals","State vector group","Show earthing connections"],"distinction":"The Y-Y label does not by itself establish neutral availability.","facts":[{"label":"Drawing role","value":"Winding connection"},{"label":"Representation scope","value":"Functional concept; not an official standard graphic or a product footprint"},{"label":"Public vendor block reference","value":"HXF1T7, VXF1T7 (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":"autodesk-transformers","relevance":"Public documentation of this equipment function or named vendor variant; the illustration is independently authored and is not the source graphic."},{"sourceId":"pub-symbol-three-phase-transformers","relevance":"Public documentation of this equipment function or named vendor variant; the illustration is independently authored and is not the source graphic."}],"related":["power-transformer","voltage-transformer"],"artwork":"edu-star-star-transformer","publishedOn":"2026-10-13","updatedOn":"2026-10-13","provenance":"independent-public-research","url":"https://eloragrid.ai/symbols/star-star-transformer","illustration":{"url":"https://eloragrid.ai/library/illustrations/star-star-transformer.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"autodesk-transformers","title":"Power, potential and autotransformer symbols","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-C1FE1690-DBF4-4F69-85C4-28E41F0A6392.htm","type":"cad-reference","scope":"Power transformers, voltage transformers, winding counts, screens and autotransformers.","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":"pub-symbol-three-phase-transformers","title":"AutoCAD Electrical: Three-phase transformer connections","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-EB13DB13-01EE-4541-BED7-19B9001BE8FC.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."}]}