{"schemaVersion":1,"slug":"semi-pantograph-disconnector-reference","name":"Semi-pantograph disconnector reference","kind":"symbol","abbreviation":"SDR","aliases":["Disconnector and earthing applications","switchyards Disconnector and earthing applications","switchyards","Switchyards","Bay primary terminal","Semi-pantograph bus connection"],"category":"power-distribution","drawingTypes":["Schematic"],"referenceFamilies":["Manufacturer"],"summary":"Identifies the documented semi-pantograph construction at its assigned yard connection.","description":["Identifies the documented semi-pantograph construction at its assigned yard connection. Disconnector and earthing references identify different mechanical constructions and connection duties within a yard. The primary diagram shows which conductors are joined or earthed; the equipment drawing explains how its contacts and supports move.","In a switchyard bay, a bus selector can use a different physical construction from a line disconnector. Each device still needs an identified operating mechanism, position indication and interlocking interface. For this reference, the drawing identifies “Bay primary terminal” at the input and “Semi-pantograph bus connection” at the output. Its operating envelope differs from other constructions.","The construction name does not establish load-breaking capability, short-circuit making duty or operating permission. Verify these properties in the selected equipment data and the station interlocking scheme. The functional block is an independent explanation of this named application. Equipment-specific ratings, terminal connections and operating conditions must be established in the project documentation."],"readingNotes":["Start at the named input: Bay primary terminal. Identify its source device or document and the state represented on the drawing.","Follow the named output: Semi-pantograph bus connection. Cross-reference its destination and separate the command from confirmation that the equipment responded.","Its operating envelope differs from other constructions.","The construction name does not establish load-breaking capability, short-circuit making duty or operating permission. Verify these properties in the selected equipment data and the station interlocking scheme."],"drawingChecklist":["Label the source and connection reference for bay primary terminal.","Identify the destination and defined state of semi-pantograph bus connection.","Record the equipment or control-document revision supporting this functional block.","Check this application limit in the project design: Its operating envelope differs from other constructions."],"distinction":"Its operating envelope differs from other constructions. This reference describes the named application; it does not establish a new IEC graphical symbol, an ANSI device-function number or an exact manufacturer connection diagram.","facts":[{"label":"Representation","value":"Functional block"},{"label":"Installation focus","value":"Switchyards"},{"label":"Input / boundary","value":"Bay primary terminal"},{"label":"Output / connection","value":"Semi-pantograph bus connection"},{"label":"Lookup label","value":"SDR is a library lookup label, not a standard device designation."}],"references":[{"sourceId":"pi26-disconnectors","relevance":"Public technical context for disconnector and earthing applications. Disconnector construction, earthing switches and operating mechanisms. The application text and educational graphic are independently authored; the publisher does not certify this representation."}],"related":["disconnector","earthing-switch","knee-type-disconnector-application-reference"],"artwork":"pi26-semi-pantograph-disconnector-reference","publishedOn":"2026-11-03","updatedOn":"2026-11-03","provenance":"independent-public-research","representation":{"type":"functional-block","focus":"switchyards","family":"yard-disconnectors","input":"Bay primary terminal","output":"Semi-pantograph bus connection"},"plainEnglish":{"title":"What this block does","introduction":"Identifies the documented semi-pantograph construction at its assigned yard connection.","example":"In a switchyard bay, a bus selector can use a different physical construction from a line disconnector. Each device still needs an identified operating mechanism, position indication and interlocking interface. For this reference, the drawing identifies “Bay primary terminal” at the input and “Semi-pantograph bus connection” at the output. Its operating envelope differs from other constructions.","drawings":"Start at the named input: Bay primary terminal. Identify its source device or document and the state represented on the drawing. Follow the named output: Semi-pantograph bus connection. Cross-reference its destination and separate the command from confirmation that the equipment responded.","terms":[{"name":"Input","meaning":"Bay primary terminal"},{"name":"Output","meaning":"Semi-pantograph bus connection"},{"name":"Application reference","meaning":"An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections."}],"diagram":"flow","steps":["Bay primary terminal","SDR","Semi-pantograph bus connection"],"caption":"A reading guide. The entry's original illustration and input/output facts describe this application.","sources":[{"label":"Disconnectors and earthing switches","url":"https://www.siemens-energy.com/global/en/home/products-services/product-offerings/disconnectors-earthing-switches.html"}],"profileId":"power-installation-yard-disconnectors"},"url":"https://eloragrid.ai/symbols/semi-pantograph-disconnector-reference","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/semi-pantograph-disconnector-reference.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pi26-disconnectors","publisher":"Siemens Energy","title":"Disconnectors and earthing switches","url":"https://www.siemens-energy.com/global/en/home/products-services/product-offerings/disconnectors-earthing-switches.html","scope":"Disconnector construction, earthing switches and operating mechanisms.","type":"manufacturer","checkedOn":"2026-11-03","reuse":"link-only","relevance":"Public technical context for disconnector and earthing applications. Disconnector construction, earthing switches and operating mechanisms. The application text and educational graphic are independently authored; the publisher does not certify this representation."}]}