{"schemaVersion":1,"slug":"unidirectional-semiconductor-power-switch","name":"Unidirectional semiconductor power switch","kind":"symbol","abbreviation":"SSW UNI","aliases":["HCB11Q57","VCB11Q57"],"category":"power-distribution","drawingTypes":["SLD","Schematic"],"referenceFamilies":["IEC","Manufacturer"],"summary":"A unidirectional semiconductor switch has a specified direction for its power conduction or control behaviour.","description":["A unidirectional semiconductor switch has a specified direction for its power conduction or control behaviour. The functional direction must be identified so reversing a schematic orientation does not reverse the intended meaning."],"readingNotes":["Use terminal polarity and the product circuit rather than page orientation to determine direction.","The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation."],"drawingChecklist":["Show permitted conduction direction","Identify control polarity","Reference reverse-voltage capability"],"distinction":"Unidirectional operation concerns the circuit path; it does not describe the direction of all system power flows.","facts":[{"label":"Drawing role","value":"Switching path"},{"label":"Representation scope","value":"Functional concept; not an official standard graphic or a product footprint"},{"label":"Public vendor block reference","value":"HCB11Q57, VCB11Q57 (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-power-switches","relevance":"Public documentation of this equipment function or named vendor variant; the illustration is independently authored and is not the source graphic."}],"related":["disconnector","circuit-breaker"],"artwork":"edu-unidirectional-semiconductor-power-switch","publishedOn":"2026-10-13","updatedOn":"2026-10-13","provenance":"independent-public-research","url":"https://eloragrid.ai/symbols/unidirectional-semiconductor-power-switch","illustration":{"url":"https://eloragrid.ai/library/illustrations/unidirectional-semiconductor-power-switch.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-power-switches","title":"AutoCAD Electrical: Power semiconductor switches","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-54E4231E-F794-4527-9104-C2D7BA312077.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."}]}