CO
Changeover contact
A contact arrangement switching a common connection between two contact paths.
Schematic
Symbols · SS
Selector switch
An operator switch selecting between documented control positions.
Schematic · SS
What it represents
A selector switch provides a choice between operating positions such as local and remote or manual and automatic. Its contacts may be shown separately from the operator symbol. The contact truth table or switching schedule defines which contacts operate in each position.
Maintained positions and spring-return positions behave differently. Labels, detents and return direction should be made explicit. A contact mark alone cannot describe the full switching sequence of a multi-position selector.
How to read it
- Read the position labels and any contact schedule together.
- Identify maintained positions and returning positions from documented operator data.
Information to show or reference
- Name each position.
- Reference the associated contact blocks and terminals.
- Show the return behaviour and switching schedule.
A distinction that matters
A changeover contact describes connections; a selector switch also includes an operator and its position behaviour.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
Selector-switch contact and operating variants
Public selector-switch positions and contact variants.
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.
Explore related references
PB NO
Normally open pushbutton
A pushbutton contact normally shown open before actuation.
Schematic
NO
Normally open contact
A contact shown open in the normal state defined for its device.
Schematic
Control GA
Control / marshalling cabinet
A generic cabinet organising control equipment, terminals and field interfaces.
GA objects
Put the reference into a drawing workflow.
Elora Grid helps electrical teams work with drawings, specifications and equipment information. Explore the drafting workflow or join the early-access waitlist.