{"schemaVersion":1,"slug":"static-frequency-converter","name":"Static frequency converter","kind":"symbol","abbreviation":"SFC","aliases":["frequency converter","50/60 Hz converter","AC-to-AC converter"],"category":"microgrid-systems","drawingTypes":["SLD"],"referenceFamilies":["IEC","IEEE / ANSI"],"summary":"A rectifier and inverter in one unit that converts AC at one frequency to AC at another, such as 50 Hz to 60 Hz.","description":["A static frequency converter rectifies the incoming AC to DC and inverts it back to AC at a different frequency and often a different voltage. It is used to supply 60 Hz equipment from a 50 Hz network, to provide shore power to ships, to feed 400 Hz aircraft supplies and to link microgrids or networks running at different frequencies.","Drawings show a converter box with AC marks on both sides and the frequencies noted, or two converter boxes back to back with a DC link between them. Input and output transformers are often drawn to provide isolation and voltage matching.","The output is converter-sourced, so fault current is limited and selective protection downstream must be checked. The symbol does not show overload capability or whether the output can supply motor starting current."],"readingNotes":["Read both the input and output frequency labels.","Check output short-circuit capability for downstream protection."],"drawingChecklist":["State input and output voltage and frequency.","Show isolation transformers.","Reference overload and fault capability."],"distinction":"A static frequency converter changes frequency electronically; a motor-generator set does the same with rotating machines.","facts":[{"label":"Conversion","value":"AC to DC to AC"},{"label":"Typical use","value":"50/60 Hz and 400 Hz supplies"},{"label":"Fault current","value":"Converter-limited"},{"label":"Preview","value":"Independent educational illustration; consult the applicable standard and project legend for the exact graphic"}],"references":[{"sourceId":"iec-diagrams","relevance":"IEC graphical symbol context for converters."},{"sourceId":"pub-electronics-infineon-inverter","relevance":"Public AC/DC and inverter stage context."}],"related":["motor-generator-set","power-converter","dc-to-ac-inverter","active-front-end-rectifier"],"artwork":"s28-static-frequency-converter","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","plainEnglish":{"title":"What does Static frequency converter mean?","introduction":"A static frequency converter rectifies the incoming AC to DC and inverts it back to AC at a different frequency and often a different voltage. It is used to supply 60 Hz equipment from a 50 Hz network, to provide shore power to ships, to feed 400 Hz aircraft supplies and to link microgrids or networks running at different frequencies.","example":"Drawings show a converter box with AC marks on both sides and the frequencies noted, or two converter boxes back to back with a DC link between them. Input and output transformers are often drawn to provide isolation and voltage matching.","drawings":"The output is converter-sourced, so fault current is limited and selective protection downstream must be checked. The symbol does not show overload capability or whether the output can supply motor starting current.","terms":[{"name":"DC","meaning":"Direct current: electricity flowing in one direction."},{"name":"AC","meaning":"Alternating current: electricity whose direction changes periodically."},{"name":"Winding","meaning":"A coil of conductor inside an electrical machine or transformer."}],"diagram":"flow","steps":["Identify the device and form","Read the connections and state","Check the equipment reference"],"caption":"A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.","sources":[{"label":"IEC graphical symbols for diagrams","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/"},{"label":"Bidirectional three-/single-phase AC/DC PFC and inverter application note","url":"https://www.infineon.com/assets/row/public/documents/24/42/infineon-ac-dc-pfc-11-kw-high-efficiency-high-density-bidirectional-three-single-phase-inverter-applicationnotes-en.pdf"}],"detail":"A rectifier and inverter in one unit that converts AC at one frequency to AC at another, such as 50 Hz to 60 Hz. A static frequency converter changes frequency electronically; a motor-generator set does the same with rotating machines.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/static-frequency-converter","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/static-frequency-converter.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"iec-diagrams","title":"IEC graphical symbols for diagrams","publisher":"IEC","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/","type":"standard","scope":"IEC 60617 and related symbol-design publications. Full database access requires a subscription.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"IEC graphical symbol context for converters."},{"id":"pub-electronics-infineon-inverter","title":"Bidirectional three-/single-phase AC/DC PFC and inverter application note","publisher":"Infineon Technologies","url":"https://www.infineon.com/assets/row/public/documents/24/42/infineon-ac-dc-pfc-11-kw-high-efficiency-high-density-bidirectional-three-single-phase-inverter-applicationnotes-en.pdf","type":"manufacturer","scope":"Public application context for actively switched AC/DC and inverter stages. Independent miniature topology illustrations have no copied product-specific values, wiring layouts or control implementation.","checkedOn":"2026-10-14","reuse":"link-only","relevance":"Public AC/DC and inverter stage context."}]}