# ANSI/IEEE Make-before-break changeover contact form Canonical URL: https://eloragrid.ai/symbols/ansi-make-before-break-changeover-contact Publisher: Elora Grid Updated: 2026-10-28 Lookup label: MBB Drawing use: Schematic Reference families: IEEE / ANSI, Manufacturer ## Symbol convention Convention: IEEE / ANSI Form: Transfer Make Before Break Contact Autodesk IEEE Symbol Preview: Miscellaneous Switches, block HSW1SC7_F. Matching functional counterpart linked separately. Independently drawn educational geometry; not a certified IEEE glyph or database identifier. Related representation: [Make-before-break changeover contact](https://eloragrid.ai/symbols/make-before-break-changeover-contact) IEEE-library reference for make-before-break changeover contact, with its operating meaning, connection notes and public vendor block identity. ## In plain English ### What does ANSI/IEEE Make-before-break changeover contact form mean? This reference locates make-before-break changeover contact in Autodesk's IEEE-oriented miscellaneous switches family. A make-before-break changeover contact establishes the next path before releasing the previous path during its documented transfer. The temporary overlap must be understood for the connected circuits. The public library uses HSW1SC7_F for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number. ### A simple example Read the operating mechanism and the contact reference state together. Cross-reference every associated contact to the same device and show which movement, signal or reset changes its condition; the symbol alone does not establish the complete switching sequence. ### What the drawings help you do Identify any circuits that would be interconnected during the overlap. A break-before-make transfer opens the previous path before establishing the next. The linked functional counterpart explains the same operating role in its own drawing context; agreement of every detailed convention mark is not asserted. ### This particular reference IEEE-library reference for make-before-break changeover contact, with its operating meaning, connection notes and public vendor block identity. A break-before-make transfer opens the previous path before establishing the next. ### Terms - Normally open / normally closed: The contact state in the normal condition defined for the drawing. - Signal: Electrical information passed between devices, rather than necessarily the main power supply. - Rating: A value stating the conditions for which equipment is specified. Concept diagram: Identify the device and form → Read the connections and state → Check the equipment reference A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram. - [Autodesk IEEE Symbol Preview — Miscellaneous Switches](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-278F6C21-B1A6-4EA1-A535-E78D53BBD10D.htm) ## What it represents This reference locates make-before-break changeover contact in Autodesk's IEEE-oriented miscellaneous switches family. A make-before-break changeover contact establishes the next path before releasing the previous path during its documented transfer. The temporary overlap must be understood for the connected circuits. The public library uses HSW1SC7_F for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number. Read the operating mechanism and the contact reference state together. Cross-reference every associated contact to the same device and show which movement, signal or reset changes its condition; the symbol alone does not establish the complete switching sequence. Identify any circuits that would be interconnected during the overlap. A break-before-make transfer opens the previous path before establishing the next. The linked functional counterpart explains the same operating role in its own drawing context; agreement of every detailed convention mark is not asserted. ## How to read it - Identify any circuits that would be interconnected during the overlap. - The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation. ## Information to show or reference - Label common and throw terminals - State overlap sequence - Reference connected-circuit compatibility ## Important distinction A break-before-make transfer opens the previous path before establishing the next. ## Facts - Convention evidence: Autodesk IEEE Symbol Preview: Miscellaneous Switches; published form: Transfer Make Before Break Contact. - Public vendor block: HSW1SC7_F. Vendor library token, not an IEEE symbol number. - Drawing role: Contact state - Identifier status: The short label is a functional lookup label, not an assigned IEC or IEEE symbol number. Any separately listed Autodesk code is a verified vendor block name. - Artwork scope: Original educational geometry. Exact standard graphics, product ratings and terminal pinouts are not certified. ## Public references - [Autodesk IEEE Symbol Preview — Miscellaneous Switches](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-278F6C21-B1A6-4EA1-A535-E78D53BBD10D.htm) — Autodesk. Public IEEE-oriented Miscellaneous Switches table explicitly lists HSW1SC7_F as Transfer Make Before Break Contact. This supports the vendor convention context, not reproduction of the publisher graphic. ## Graphic scope Independent original educational concept illustration by Elora Grid. Not a certified standards graphic or manufacturer footprint. Unitless; not to scale. Original artwork licence: https://creativecommons.org/licenses/by/4.0/. Publisher material is linked only.