{"schemaVersion":1,"slug":"ansi-main-bonding-jumper","name":"ANSI/IEEE main bonding jumper symbol","kind":"symbol","abbreviation":"MBJ","aliases":["main bonding jumper","service bonding jumper","neutral to ground bond US"],"category":"connections-wiring","drawingTypes":["SLD","Schematic"],"referenceFamilies":["IEEE / ANSI"],"summary":"US-practice bonding jumper between the grounded neutral and the equipment grounding system at the service.","description":["In North American practice the main bonding jumper connects the grounded conductor, the neutral, to the equipment grounding conductor and enclosure at the service equipment. Its function corresponds to the neutral-to-earth link in TN-C-S systems. Single-line diagrams show it at the service disconnect, and separately derived systems have a corresponding system bonding jumper.","This illustration is an independent explanation and not an IEEE graphic. Only one bond should exist per service or separately derived system. Sizing rules come from the applicable electrical code, and the drawing should state the conductor or strap size."],"readingNotes":["Locate the bond at the service or derived system source only.","Check for unwanted downstream neutral to ground bonds."],"drawingChecklist":["Show the jumper at the service equipment.","State jumper size.","Show system bonding jumpers on separately derived systems."],"distinction":"A main bonding jumper bonds neutral and ground at the service; an equipment bonding jumper bonds metal parts together.","facts":[{"label":"Convention evidence","value":"IEEE 315 graphic conventions for ground and bonding (standards context only)"},{"label":"Equivalent concept","value":"Neutral to earth link in TN-C-S practice"},{"label":"Standards context","value":"IEEE/ANSI 315-1975 covers diagram graphics; IEEE lists this edition as Inactive-Reserved."},{"label":"Preview","value":"Original educational illustration; consult the publisher and applicable standard for the exact graphic"}],"references":[{"sourceId":"ieee-315","relevance":"Graphic-symbol standards context and official status; not a source of reproduced artwork."},{"sourceId":"ansi-autodesk-34282bfd-7b8e-48f3-a6ed-93adbdddfbd3","relevance":"Public IEEE-oriented earth and bonding forms."}],"related":["iec-men-link","ansi-protective-earth","ansi-protective-equipotential-bonding"],"artwork":"s28-ansi-main-bonding-jumper","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","symbolVariant":{"convention":"IEEE / ANSI","form":"Main bonding jumper form","reference":"Independent illustration in IEEE drafting context; no equivalence of every detailed standard graphic is asserted."},"plainEnglish":{"title":"What does ANSI/IEEE main bonding jumper mean?","introduction":"In North American practice the main bonding jumper connects the grounded conductor, the neutral, to the equipment grounding conductor and enclosure at the service equipment. Its function corresponds to the neutral-to-earth link in TN-C-S systems. Single-line diagrams show it at the service disconnect, and separately derived systems have a corresponding system bonding jumper.","example":"This illustration is an independent explanation and not an IEEE graphic. Only one bond should exist per service or separately derived system. Sizing rules come from the applicable electrical code, and the drawing should state the conductor or strap size.","drawings":"Locate the bond at the service or derived system source only. Check for unwanted downstream neutral to ground bonds. A main bonding jumper bonds neutral and ground at the service; an equipment bonding jumper bonds metal parts together.","terms":[{"name":"Schematic","meaning":"A drawing showing function and connections rather than physical appearance."}],"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":"IEEE/ANSI 315-1975: graphic symbols for electrical and electronics diagrams","url":"https://standards.ieee.org/ieee/315/515/"},{"label":"Autodesk IEEE Symbol Preview — Miscellaneous","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-34282BFD-7B8E-48F3-A6ED-93ADBDDDFBD3.htm"}],"detail":"US-practice bonding jumper between the grounded neutral and the equipment grounding system at the service. A main bonding jumper bonds neutral and ground at the service; an equipment bonding jumper bonds metal parts together.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/ansi-main-bonding-jumper","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/ansi-main-bonding-jumper.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"ieee-315","title":"IEEE/ANSI 315-1975: graphic symbols for electrical and electronics diagrams","publisher":"IEEE Standards Association","url":"https://standards.ieee.org/ieee/315/515/","type":"standard","scope":"Graphic symbols and designation letters. IEEE lists this edition as Inactive-Reserved; it is a historical reference, not a claim of current compliance.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Graphic-symbol standards context and official status; not a source of reproduced artwork."},{"id":"ansi-autodesk-34282bfd-7b8e-48f3-a6ed-93adbdddfbd3","title":"Autodesk IEEE Symbol Preview — Miscellaneous","publisher":"Autodesk","url":"https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-34282BFD-7B8E-48F3-A6ED-93ADBDDDFBD3.htm","type":"cad-reference","scope":"Verified public IEEE-oriented vendor catalogue. Block names identify vendor symbols, not IEEE standard symbol numbers. Linked only; graphics and CAD files are not redistributed. IEEE/ANSI 315-1975 is a historical graphics reference with Inactive-Reserved status; this page does not certify current standards compliance.","checkedOn":"2026-10-14","reuse":"link-only","relevance":"Public IEEE-oriented earth and bonding forms."}]}