{"schemaVersion":1,"slug":"ansi-unidirectional-semiconductor-power-switch","name":"ANSI/IEEE Unidirectional semiconductor power switch form","kind":"symbol","abbreviation":"SSW UNI","aliases":["HCB11Q57","VCB11Q57","IEEE 1P with Semiconductors - unidirectional","ANSI Unidirectional semiconductor power switch"],"category":"power-distribution","drawingTypes":["SLD","Schematic"],"referenceFamilies":["IEEE / ANSI","Manufacturer"],"summary":"IEEE-library form of unidirectional semiconductor power switch: a unidirectional semiconductor switch has a specified direction for its power conduction or control behaviour.","description":["This reference locates unidirectional semiconductor power switch in Autodesk's IEEE-oriented power switches family. 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. The public library uses HCB11Q57 for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number.","Read the operating mechanism and the contact reference state together. Cross-reference every associated contact to the same device and show which movement, signal or reset changes its condition; the symbol alone does not establish the complete switching sequence.","Use terminal polarity and the product circuit rather than page orientation to determine direction. Unidirectional operation concerns the circuit path; it does not describe the direction of all system power flows. The linked functional counterpart explains the same operating role in its own drawing context; agreement of every detailed convention mark is not asserted."],"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":"Convention evidence","value":"Autodesk IEEE Symbol Preview: Power Switches; published form: 1P with Semiconductors - unidirectional."},{"label":"Public vendor block","value":"HCB11Q57. Vendor library token, not an IEEE symbol number."},{"label":"Drawing role","value":"Switching path"},{"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."},{"label":"Artwork scope","value":"Original educational geometry. Exact standard graphics, product ratings and terminal pinouts are not certified."}],"references":[{"sourceId":"s28-ieee-power-switches","relevance":"Public IEEE-oriented Power Switches table explicitly lists HCB11Q57 as 1P with Semiconductors - unidirectional. This supports the vendor convention context, not reproduction of the publisher graphic."}],"related":["unidirectional-semiconductor-power-switch","disconnector","circuit-breaker"],"artwork":"s28-ansi-unidirectional-semiconductor-power-switch","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","symbolVariant":{"convention":"IEEE / ANSI","form":"1P with Semiconductors - unidirectional","reference":"Autodesk IEEE Symbol Preview: Power Switches, block HCB11Q57. Matching functional counterpart linked separately. Independently drawn educational geometry; not a certified IEEE glyph or database identifier.","counterpart":"unidirectional-semiconductor-power-switch"},"plainEnglish":{"title":"What does ANSI/IEEE Unidirectional semiconductor power switch form mean?","introduction":"This reference locates unidirectional semiconductor power switch in Autodesk's IEEE-oriented power switches family. 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. The public library uses HCB11Q57 for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number.","example":"Read the operating mechanism and the contact reference state together. Cross-reference every associated contact to the same device and show which movement, signal or reset changes its condition; the symbol alone does not establish the complete switching sequence.","drawings":"Use terminal polarity and the product circuit rather than page orientation to determine direction. Unidirectional operation concerns the circuit path; it does not describe the direction of all system power flows. The linked functional counterpart explains the same operating role in its own drawing context; agreement of every detailed convention mark is not asserted.","terms":[{"name":"Normally open / normally closed","meaning":"The contact state in the normal condition defined for the drawing."},{"name":"Terminal","meaning":"An identified point where a conductor connects."},{"name":"Signal","meaning":"Electrical information passed between devices, rather than necessarily the main power supply."}],"diagram":"flow","steps":["Identify the device and form","Read the connections and state","Check the equipment reference"],"caption":"A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.","sources":[{"label":"Autodesk IEEE Symbol Preview: Power Switches","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-E57D79F6-E6C4-4B78-95DC-62F16642C95B.htm"}],"detail":"IEEE-library form of unidirectional semiconductor power switch: a unidirectional semiconductor switch has a specified direction for its power conduction or control behaviour. Unidirectional operation concerns the circuit path; it does not describe the direction of all system power flows.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/ansi-unidirectional-semiconductor-power-switch","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/ansi-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":"s28-ieee-power-switches","title":"Autodesk IEEE Symbol Preview: Power Switches","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-E57D79F6-E6C4-4B78-95DC-62F16642C95B.htm","type":"cad-reference","scope":"Public power switches family names and vendor block tokens. Horizontal, vertical and rotated placements are not separate engineering functions. Exact standard geometry is not reproduced.","checkedOn":"2026-10-28","reuse":"link-only","relevance":"Public IEEE-oriented Power Switches table explicitly lists HCB11Q57 as 1P with Semiconductors - unidirectional. This supports the vendor convention context, not reproduction of the publisher graphic."}]}