{"schemaVersion":1,"slug":"three-phase-star-autotransformer","name":"Three-phase star autotransformer","kind":"symbol","abbreviation":"AT 3PH Y","aliases":["HXF1T19","VXF1T19"],"category":"power-distribution","drawingTypes":["SLD","Schematic"],"referenceFamilies":["IEC","Manufacturer"],"summary":"A three-phase star-connected autotransformer has electrically shared winding portions arranged in a three-phase star connection.","description":["A three-phase star-connected autotransformer has electrically shared winding portions arranged in a three-phase star connection. Its neutral and tap connections need explicit identification."],"readingNotes":["Determine how the common star point and any accessible neutral are used by the design.","The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation."],"drawingChecklist":["Show star point","State winding voltage ratios","Reference tap terminals"],"distinction":"A star autotransformer is electrically different from a star-star two-winding transformer.","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":"HXF1T19, VXF1T19 (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."}],"related":["power-transformer","voltage-transformer"],"artwork":"edu-three-phase-star-autotransformer","publishedOn":"2026-10-13","updatedOn":"2026-10-13","provenance":"independent-public-research","url":"https://eloragrid.ai/symbols/three-phase-star-autotransformer","illustration":{"url":"https://eloragrid.ai/library/illustrations/three-phase-star-autotransformer.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."}]}