{"schemaVersion":1,"slug":"microgrid-grid-forming-reference-selection","name":"Microgrid grid-forming reference selection","kind":"symbol","abbreviation":"MGRS","aliases":["Microgrid operating-mode controls","microgrids Microgrid operating-mode controls","microgrids","Microgrids","Grid-forming resource availability","Selected island reference"],"category":"microgrid-systems","drawingTypes":["Schematic"],"referenceFamilies":["Manufacturer"],"summary":"Selects the available source assigned to establish the island voltage and frequency reference.","description":["Selects the available source assigned to establish the island voltage and frequency reference. A microgrid operating-mode function coordinates how local sources and loads relate to the utility connection. The selected mode, the measured electrical condition and the actual switching configuration can differ during a transition.","In a microgrid serving a switchroom and industrial loads, the controller can move between grid-connected and islanded operating states only through its defined transition logic. Each state needs identifiable source roles and feedback. For this reference, the drawing identifies “Grid-forming resource availability” at the input and “Selected island reference” at the output. Reference transfer requires a validated control scheme.","Show the requested mode, entry conditions, completion feedback and failure indication. These functional blocks explain control responsibilities and do not specify a ready-to-use operating sequence or grid-connection approval. 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: Grid-forming resource availability. Identify its source device or document and the state represented on the drawing.","Follow the named output: Selected island reference. Cross-reference its destination and separate the command from confirmation that the equipment responded.","Reference transfer requires a validated control scheme.","Show the requested mode, entry conditions, completion feedback and failure indication. These functional blocks explain control responsibilities and do not specify a ready-to-use operating sequence or grid-connection approval."],"drawingChecklist":["Label the source and connection reference for grid-forming resource availability.","Identify the destination and defined state of selected island reference.","Record the equipment or control-document revision supporting this functional block.","Check this application limit in the project design: Reference transfer requires a validated control scheme."],"distinction":"Reference transfer requires a validated control scheme. 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":"Grid-forming resource availability"},{"label":"Output / connection","value":"Selected island reference"},{"label":"Lookup label","value":"MGRS is a library lookup label, not a standard device designation."}],"references":[{"sourceId":"pi26-mg-modes","relevance":"Public technical context for microgrid operating-mode controls. 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-controller","grid-forming-inverter","microgrid-mode-change-rejection-indication"],"artwork":"pi26-microgrid-grid-forming-reference-selection","publishedOn":"2026-11-03","updatedOn":"2026-11-03","provenance":"independent-public-research","representation":{"type":"functional-block","focus":"microgrids","family":"microgrid-modes","input":"Grid-forming resource availability","output":"Selected island reference"},"plainEnglish":{"title":"What this block does","introduction":"Selects the available source assigned to establish the island voltage and frequency reference.","example":"In a microgrid serving a switchroom and industrial loads, the controller can move between grid-connected and islanded operating states only through its defined transition logic. Each state needs identifiable source roles and feedback. For this reference, the drawing identifies “Grid-forming resource availability” at the input and “Selected island reference” at the output. Reference transfer requires a validated control scheme.","drawings":"Start at the named input: Grid-forming resource availability. Identify its source device or document and the state represented on the drawing. Follow the named output: Selected island reference. Cross-reference its destination and separate the command from confirmation that the equipment responded.","terms":[{"name":"Input","meaning":"Grid-forming resource availability"},{"name":"Output","meaning":"Selected island reference"},{"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":["Grid-forming resource availability","MGRS","Selected island reference"],"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-modes"},"url":"https://eloragrid.ai/symbols/microgrid-grid-forming-reference-selection","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/microgrid-grid-forming-reference-selection.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 operating-mode controls. 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."}]}