{"schemaVersion":1,"slug":"busbar-extension-isolation-arrangement","name":"Busbar extension isolation arrangement","kind":"symbol","abbreviation":"BEIA","aliases":["Switchyard busbar arrangements","switchyards Switchyard busbar arrangements","switchyards","Switchyards","Existing bus and extension boundary","Separated extension interface"],"category":"power-distribution","drawingTypes":["SLD","Schematic"],"referenceFamilies":["Manufacturer"],"summary":"Identifies the designed isolation boundary between an operating bus and its extension interface.","description":["Identifies the designed isolation boundary between an operating bus and its extension interface. A busbar arrangement defines the available paths between incoming circuits, outgoing circuits and bus sections. Its switching devices and measurement boundaries determine how a circuit can remain connected when part of the installation is unavailable.","In a switchyard, a single-line arrangement helps identify the bay connections, tie devices and possible alternate supply paths. Normal open points must remain separate from the equipment's physical ability to close. For this reference, the drawing identifies “Existing bus and extension boundary” at the input and “Separated extension interface” at the output. The illustration does not authorize construction access.","Name each bus, bay and switching device. The arrangement illustrates electrical connectivity; reliability, fault levels, permitted switching and protection coordination require the actual network design. The circuit arrangement 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: Existing bus and extension boundary. Identify its source device or document and the state represented on the drawing.","Follow the named output: Separated extension interface. Cross-reference its destination and separate the command from confirmation that the equipment responded.","The illustration does not authorize construction access.","Name each bus, bay and switching device. The arrangement illustrates electrical connectivity; reliability, fault levels, permitted switching and protection coordination require the actual network design."],"drawingChecklist":["Label the source and connection reference for existing bus and extension boundary.","Identify the destination and defined state of separated extension interface.","Record the equipment or control-document revision supporting this circuit arrangement.","Check this application limit in the project design: The illustration does not authorize construction access."],"distinction":"The illustration does not authorize construction access. 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":"Circuit arrangement"},{"label":"Installation focus","value":"Switchyards"},{"label":"Input / boundary","value":"Existing bus and extension boundary"},{"label":"Output / connection","value":"Separated extension interface"},{"label":"Lookup label","value":"BEIA is a library lookup label, not a standard device designation."}],"references":[{"sourceId":"pi26-bus-schemes","relevance":"Public technical context for switchyard busbar arrangements. Bus arrangements, breaker control and bay-level coordination. The application text and educational graphic are independently authored; the publisher does not certify this representation."}],"related":["busbar","disconnector","normally-split-busbar-operating-arrangement"],"artwork":"pi26-busbar-extension-isolation-arrangement","publishedOn":"2026-11-03","updatedOn":"2026-11-03","provenance":"independent-public-research","representation":{"type":"circuit-arrangement","focus":"switchyards","family":"yard-buses","input":"Existing bus and extension boundary","output":"Separated extension interface"},"plainEnglish":{"title":"What this arrangement shows","introduction":"Identifies the designed isolation boundary between an operating bus and its extension interface.","example":"In a switchyard, a single-line arrangement helps identify the bay connections, tie devices and possible alternate supply paths. Normal open points must remain separate from the equipment's physical ability to close. For this reference, the drawing identifies “Existing bus and extension boundary” at the input and “Separated extension interface” at the output. The illustration does not authorize construction access.","drawings":"Start at the named input: Existing bus and extension boundary. Identify its source device or document and the state represented on the drawing. Follow the named output: Separated extension interface. Cross-reference its destination and separate the command from confirmation that the equipment responded.","terms":[{"name":"Input","meaning":"Existing bus and extension boundary"},{"name":"Output","meaning":"Separated extension interface"},{"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":["Existing bus and extension boundary","BEIA","Separated extension interface"],"caption":"A reading guide. The entry's original illustration and input/output facts describe this application.","sources":[{"label":"SEL-451 protection, automation and bay control","url":"https://selinc.com/products/451/"}],"profileId":"power-installation-yard-buses"},"url":"https://eloragrid.ai/symbols/busbar-extension-isolation-arrangement","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/busbar-extension-isolation-arrangement.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pi26-bus-schemes","publisher":"SEL","title":"SEL-451 protection, automation and bay control","url":"https://selinc.com/products/451/","scope":"Bus arrangements, breaker control and bay-level coordination.","type":"manufacturer","checkedOn":"2026-11-03","reuse":"link-only","relevance":"Public technical context for switchyard busbar arrangements. Bus arrangements, breaker control and bay-level coordination. The application text and educational graphic are independently authored; the publisher does not certify this representation."}]}