CO
Changeover contact
A contact arrangement switching a common connection between two contact paths.
Schematic
IEEE / ANSI · CO
ANSI/IEEE changeover contact symbol
IEEE-oriented graphical reference for changeover contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI · Autodesk IEEE-oriented Relays and Contacts functional form
Autodesk explicitly publishes this block under IEEE Symbol Preview. The counterpart is the matching functional concept; no equivalence of every detailed standard graphic is asserted.
Shown as an independently authored educational illustration. Use the cited publication and drawing legend to verify the required drafting form.
Schematic · CO
What it represents
The Form C relay contact representation links a common connection to alternative contact paths. The reader must identify common, normally closed and normally open terminals, with transition timing specified separately where overlap matters.
This is a convention-specific lookup based on the publisher's IEEE-labelled preview. The geometry here is independently drawn to explain the connection or operation; it is not a certified reproduction of the standard graphic.
How to read it
- Trace the common terminal to each throw using the stated reference state.
- Read the selected library and the project legend together. A vendor block identifier is meaningful within its named library and is not a universal standard-symbol code.
Information to show or reference
- Label common/NO/NC
- Identify parent relay
- Reference transfer sequence
A distinction that matters
Form C identifies a changeover contact arrangement; it does not by itself establish make-before-break behaviour.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
Autodesk IEEE Symbol Preview — Relays and Contacts
Exact public IEEE-oriented category page verifying the component name and vendor block identifier.
IEEE/ANSI 315-1975: graphic symbols for electrical and electronics diagrams
Graphic-symbol standards context and official status; not a source of reproduced artwork.
About this graphic
This illustration was authored independently by Elora Grid to explain the concept. It is not reproduced from a customer drawing, an official standard graphic or a manufacturer CAD file. Its correspondence to an exact IEC or IEEE symbol identifier has not been certified.
SVG and DXF downloads contain this original artwork. DXF uses unscaled drawing units; a GA envelope supplies no product dimensions, clearances or fabrication information. Original artwork is available under CC BY 4.0. Third-party references retain their own terms.
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