{"schemaVersion":1,"slug":"15-speed-or-frequency-matching-device","name":"Speed or frequency matching device","kind":"function","abbreviation":"15","aliases":["speed matching","frequency matching","ANSI 15","IEEE device 15"],"category":"measurement-protection","drawingTypes":["SLD","Schematic"],"referenceFamilies":["IEEE / ANSI"],"summary":"Adjusts or supervises the difference between two speed or frequency references.","description":["Adjusts or supervises the difference between two speed or frequency references.","In a drafting package, connect this reference to the two references being compared. The associated drawing should trace the governor or matching command; the number identifies the role and does not specify the terminal arrangement, ratings or operating settings."],"readingNotes":["Identify the two references being compared.","Trace the governor or matching command."],"drawingChecklist":["Label the two references being compared.","Cross-reference the governor or matching command.","Identify the device tag, manual revision and logic drawing that define this implementation."],"distinction":"Matching speed or frequency is one aspect of synchronisation and does not replace the complete synchronism check.","facts":[{"label":"ANSI / IEEE function number","value":"15"},{"label":"Drawing context","value":"The two references being compared"},{"label":"Application scope","value":"Protection or apparatus-control role; exact implementation is defined by the equipment documentation."}],"references":[{"sourceId":"pub-function-sel-numbers","relevance":"Public manufacturer number/name association. Drafting explanations are independently written."},{"sourceId":"ieee-functions","relevance":"Normative device-number publication; exact edition wording and compliance require the licensed standard."}],"related":["25-synchronism-check","52-ac-circuit-breaker"],"artwork":"pub-function-box","publishedOn":"2026-10-13","updatedOn":"2026-10-13","provenance":"independent-public-research","url":"https://eloragrid.ai/protection-functions/15-speed-or-frequency-matching-device","illustration":{"url":"https://eloragrid.ai/library/illustrations/15-speed-or-frequency-matching-device.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pub-function-sel-numbers","title":"ANSI device-number and suffix reference table","publisher":"Schweitzer Engineering Laboratories","url":"https://selinc.com/pt/products/tables/ansi/","type":"manufacturer","scope":"Public Portuguese-language base-number and application-suffix table. Used to cross-check public number associations. Application-specific and historical labels need the selected drawing legend; this table is not a substitute for the licensed IEEE standard.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Public manufacturer number/name association. Drafting explanations are independently written."},{"id":"ieee-functions","title":"IEEE C37.2-2022: power-system device function numbers","publisher":"IEEE","url":"https://ieeexplore.ieee.org/document/9984140","type":"standard","scope":"Device function numbers, acronyms and contact designations. The full publication may require access through IEEE.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Normative device-number publication; exact edition wording and compliance require the licensed standard."}]}