{"schemaVersion":1,"slug":"microgrid-source-to-island-assignment","name":"Microgrid source-to-island assignment","kind":"symbol","abbreviation":"MSA","aliases":["Microgrid topology and earthing coordination","microgrids Microgrid topology and earthing coordination","microgrids","Microgrids","Source and switching states","Source island allocation"],"category":"microgrid-systems","drawingTypes":["Schematic"],"referenceFamilies":["Manufacturer"],"summary":"Maps each available connected resource to the island it presently supplies or follows.","description":["Maps each available connected resource to the island it presently supplies or follows. Microgrid topology control tracks which sources and load sections are electrically connected. The same physical installation can form several islands, so source roles, measurement boundaries and earthing interfaces must follow the established configuration.","In a microgrid with sectionalized buses, the controller can associate each connected source and load group with its current island. A mode-dependent neutral or protection interface needs its own independently validated design. For this reference, the drawing identifies “Source and switching states” at the input and “Source island allocation” at the output. A disconnected source cannot establish an island reference.","Keep measured switch positions, logical island assignment and any earthing command separate. A conceptual topology block cannot establish a safe neutral-switching arrangement or prove that a circuit is de-energized. 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: Source and switching states. Identify its source device or document and the state represented on the drawing.","Follow the named output: Source island allocation. Cross-reference its destination and separate the command from confirmation that the equipment responded.","A disconnected source cannot establish an island reference.","Keep measured switch positions, logical island assignment and any earthing command separate. A conceptual topology block cannot establish a safe neutral-switching arrangement or prove that a circuit is de-energized."],"drawingChecklist":["Label the source and connection reference for source and switching states.","Identify the destination and defined state of source island allocation.","Record the equipment or control-document revision supporting this functional block.","Check this application limit in the project design: A disconnected source cannot establish an island reference."],"distinction":"A disconnected source cannot establish an island reference. 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":"Microgrids"},{"label":"Input / boundary","value":"Source and switching states"},{"label":"Output / connection","value":"Source island allocation"},{"label":"Lookup label","value":"MSA is a library lookup label, not a standard device designation."}],"references":[{"sourceId":"pi26-mg-modes","relevance":"Public technical context for microgrid topology and earthing coordination. Grid-connected and island modes, transitions, topology and authority. The application text and educational graphic are independently authored; the publisher does not certify this representation."}],"related":["microgrid-interconnection-switch","neutral-earthing-resistor","microgrid-load-to-island-assignment"],"artwork":"pi26-microgrid-source-to-island-assignment","publishedOn":"2026-11-03","updatedOn":"2026-11-03","provenance":"independent-public-research","representation":{"type":"functional-block","focus":"microgrids","family":"microgrid-topology","input":"Source and switching states","output":"Source island allocation"},"plainEnglish":{"title":"What this block does","introduction":"Maps each available connected resource to the island it presently supplies or follows.","example":"In a microgrid with sectionalized buses, the controller can associate each connected source and load group with its current island. A mode-dependent neutral or protection interface needs its own independently validated design. For this reference, the drawing identifies “Source and switching states” at the input and “Source island allocation” at the output. A disconnected source cannot establish an island reference.","drawings":"Start at the named input: Source and switching states. Identify its source device or document and the state represented on the drawing. Follow the named output: Source island allocation. Cross-reference its destination and separate the command from confirmation that the equipment responded.","terms":[{"name":"Input","meaning":"Source and switching states"},{"name":"Output","meaning":"Source island allocation"},{"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":["Source and switching states","MSA","Source island allocation"],"caption":"A reading guide. The entry's original illustration and input/output facts describe this application.","sources":[{"label":"Microgrid operating modes and transitions management","url":"https://productinfo.se.com/emol_functional_specifications/doca0371_emol_functionalspecifications/EN/DOCA0371_EMOL_Functional_Specifications_DD00894746.xml/%24/EMOL_OperatingModesandTransitionsManagement_DD00895904"}],"profileId":"power-installation-microgrid-topology"},"url":"https://eloragrid.ai/symbols/microgrid-source-to-island-assignment","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/microgrid-source-to-island-assignment.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pi26-mg-modes","publisher":"Schneider Electric","title":"Microgrid operating modes and transitions management","url":"https://productinfo.se.com/emol_functional_specifications/doca0371_emol_functionalspecifications/EN/DOCA0371_EMOL_Functional_Specifications_DD00894746.xml/%24/EMOL_OperatingModesandTransitionsManagement_DD00895904","scope":"Grid-connected and island modes, transitions, topology and authority.","type":"manufacturer","checkedOn":"2026-11-03","reuse":"link-only","relevance":"Public technical context for microgrid topology and earthing coordination. Grid-connected and island modes, transitions, topology and authority. The application text and educational graphic are independently authored; the publisher does not certify this representation."}]}