{"schemaVersion":1,"slug":"breaker-open-earthing-interlock","name":"Breaker-open earthing interlock","kind":"symbol","abbreviation":"BEI","aliases":["Switchgear interlocking functions","switchgear Switchgear interlocking functions","switchgear","Switchgear","Breaker open indication","Earthing operation condition"],"category":"control-circuits","drawingTypes":["Schematic"],"referenceFamilies":["Manufacturer"],"summary":"Uses the assigned breaker state as one condition of earthing-switch operation.","description":["Uses the assigned breaker state as one condition of earthing-switch operation. An interlocking function permits or blocks an operation according to the positions and conditions of related equipment. Electrical, mechanical and trapped-key interlocks implement different parts of a coordinated operating philosophy.","In a switchgear feeder panel, a control diagram can prevent an incompatible combination of breaker, disconnector and earthing-switch positions. The physical equipment documents determine which restrictions are mechanically enforced. For this reference, the drawing identifies “Breaker open indication” at the input and “Earthing operation condition” at the output. Breaker opening alone does not establish isolation.","Identify each initiating position, the action being blocked and the consequence of missing feedback. An illustrative logic diagram must not be treated as an operating procedure or proof of a complete safety system. 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: Breaker open indication. Identify its source device or document and the state represented on the drawing.","Follow the named output: Earthing operation condition. Cross-reference its destination and separate the command from confirmation that the equipment responded.","Breaker opening alone does not establish isolation.","Identify each initiating position, the action being blocked and the consequence of missing feedback. An illustrative logic diagram must not be treated as an operating procedure or proof of a complete safety system."],"drawingChecklist":["Label the source and connection reference for breaker open indication.","Identify the destination and defined state of earthing operation condition.","Record the equipment or control-document revision supporting this functional block.","Check this application limit in the project design: Breaker opening alone does not establish isolation."],"distinction":"Breaker opening alone does not establish isolation. 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":"Switchgear"},{"label":"Input / boundary","value":"Breaker open indication"},{"label":"Output / connection","value":"Earthing operation condition"},{"label":"Lookup label","value":"BEI is a library lookup label, not a standard device designation."}],"references":[{"sourceId":"pi26-masterclad","relevance":"Public technical context for switchgear interlocking functions. Breaker control, mechanism, position contacts, racking interlocks and test interfaces. The application text and educational graphic are independently authored; the publisher does not certify this representation."}],"related":["iec-mechanical-interlock-between-devices","earthing-switch","truck-position-racking-interlock"],"artwork":"pi26-breaker-open-earthing-interlock","publishedOn":"2026-11-03","updatedOn":"2026-11-03","provenance":"independent-public-research","representation":{"type":"functional-block","focus":"switchgear","family":"interlocks","input":"Breaker open indication","output":"Earthing operation condition"},"plainEnglish":{"title":"What this block does","introduction":"Uses the assigned breaker state as one condition of earthing-switch operation.","example":"In a switchgear feeder panel, a control diagram can prevent an incompatible combination of breaker, disconnector and earthing-switch positions. The physical equipment documents determine which restrictions are mechanically enforced. For this reference, the drawing identifies “Breaker open indication” at the input and “Earthing operation condition” at the output. Breaker opening alone does not establish isolation.","drawings":"Start at the named input: Breaker open indication. Identify its source device or document and the state represented on the drawing. Follow the named output: Earthing operation condition. Cross-reference its destination and separate the command from confirmation that the equipment responded.","terms":[{"name":"Input","meaning":"Breaker open indication"},{"name":"Output","meaning":"Earthing operation condition"},{"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":["Breaker open indication","BEI","Earthing operation condition"],"caption":"A reading guide. The entry's original illustration and input/output facts describe this application.","sources":[{"label":"Masterclad medium-voltage switchgear: circuit-breaker section interlocks","url":"https://productinfo.se.com/masterclad_mv_switchgear_ib/6055-30-masterclad-15kv-mv-switchgear-ib/English/6055-30%20Masterclad%20MV%20Switchgear%20Indoor%20%28bookmap%29_DD00646805.xml/%24/Section6-CircuitBreakerSectionInter-58DD6EC7"}],"profileId":"power-installation-interlocks"},"url":"https://eloragrid.ai/symbols/breaker-open-earthing-interlock","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/breaker-open-earthing-interlock.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pi26-masterclad","publisher":"Schneider Electric","title":"Masterclad medium-voltage switchgear: circuit-breaker section interlocks","url":"https://productinfo.se.com/masterclad_mv_switchgear_ib/6055-30-masterclad-15kv-mv-switchgear-ib/English/6055-30%20Masterclad%20MV%20Switchgear%20Indoor%20%28bookmap%29_DD00646805.xml/%24/Section6-CircuitBreakerSectionInter-58DD6EC7","scope":"Breaker control, mechanism, position contacts, racking interlocks and test interfaces.","type":"manufacturer","checkedOn":"2026-11-03","reuse":"link-only","relevance":"Public technical context for switchgear interlocking functions. Breaker control, mechanism, position contacts, racking interlocks and test interfaces. The application text and educational graphic are independently authored; the publisher does not certify this representation."}]}