{"schemaVersion":1,"slug":"67n-directional-neutral-overcurrent","name":"Directional neutral-overcurrent","kind":"function","abbreviation":"67N","aliases":["directional residual current","neutral directional earth fault","ANSI 67N","IEEE 67N"],"category":"measurement-protection","drawingTypes":["SLD","Schematic"],"referenceFamilies":["IEEE / ANSI","Manufacturer"],"summary":"Supervises neutral or residual overcurrent with a documented directional criterion.","description":["Supervises neutral or residual overcurrent with a documented directional criterion.","The drafting record should connect this function to the residual/neutral CT source and the selected polarising quantity, then trace the directional earth-fault element and feeder trip path. Keep the complete designation and equipment tag together so that the SLD, relay logic and terminal schedule describe the same implementation.","The cited mapping is a public manufacturer example (SEL public device-number table). Suffixes are not universal equivalences across products, and this reference supplies neither a protection setting nor certification of the selected scheme."],"readingNotes":["Identify the residual/neutral CT source and the selected polarising quantity.","Trace the directional earth-fault element and feeder trip path."],"drawingChecklist":["Label the residual/neutral CT source and the selected polarising quantity.","Cross-reference the directional earth-fault element and feeder trip path.","Retain the complete suffix, selected device tag and manufacturer manual revision."],"distinction":"67N requires both a current criterion and direction information; a neutral current magnitude alone does not provide direction.","facts":[{"label":"Function designation","value":"67N"},{"label":"Base function","value":"67 — Directional overcurrent"},{"label":"Published mapping","value":"SEL public device-number table"},{"label":"Suffix scope","value":"Application or manufacturer specific; check the complete drawing legend and selected device manual."}],"references":[{"sourceId":"pub-function-sel-numbers","relevance":"Public primary-source function or application mapping used to identify this designation; wording and drafting notes are original."},{"sourceId":"ieee-functions","relevance":"Device-number and suffix convention. This page is not a reproduction of the full licensed standard."}],"related":["67-directional-overcurrent","current-transformer"],"artwork":"pub-function-box","publishedOn":"2026-10-13","updatedOn":"2026-10-13","provenance":"independent-public-research","url":"https://eloragrid.ai/protection-functions/67n-directional-neutral-overcurrent","illustration":{"url":"https://eloragrid.ai/library/illustrations/67n-directional-neutral-overcurrent.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 primary-source function or application mapping used to identify this designation; wording and drafting notes are original."},{"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":"Device-number and suffix convention. This page is not a reproduction of the full licensed standard."}]}