S1
One-way light switch plan mark
Installation plan mark for a single-pole one-way switch that turns a lighting circuit on and off from one place.
IEC
IEC · SD
Dimmer switch plan mark
Plan mark for a switch that varies lamp brightness, drawn as a switch with an added variability arrow.
In plain English
What does Dimmer switch plan mark mean?
A dimmer varies the power delivered to luminaires using phase-cut electronics or a control signal. IEC-style plans typically draw the switch mark with an oblique arrow or a small adjustment mark to show continuous variation, and the switching line links it to the dimmed group.
A simple example
Dimmer compatibility with LED drivers is a frequent site problem, so the symbol is usually backed by a schedule stating the dimming method: leading edge, trailing edge, 0-10 V or DALI. The reader should check that every luminaire on the dimmed group is dimmable by that method.
What the drawings help you do
The plan mark does not state the dimming technology or minimum load. A rotary or push dimmer looks the same on the plan.
This particular reference
Plan mark for a switch that varies lamp brightness, drawn as a switch with an added variability arrow. A one-way switch has no variability mark; the dimmer adds continuous control of light output.
- Phase
- One of the related AC waveforms in a power system.
- Signal
- Electrical information passed between devices, rather than necessarily the main power supply.
- Schematic
- A drawing showing function and connections rather than physical appearance.
Read the source: IEC graphical symbols for diagrams · Autodesk IEC-60617 preview: Operating-device and function qualifiers
IEC · Dimmer switch
IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier.
Shown as an independently authored educational illustration. Use the cited publication and drawing legend to verify the required drafting form.
GA · SD
What it represents
A dimmer varies the power delivered to luminaires using phase-cut electronics or a control signal. IEC-style plans typically draw the switch mark with an oblique arrow or a small adjustment mark to show continuous variation, and the switching line links it to the dimmed group.
Dimmer compatibility with LED drivers is a frequent site problem, so the symbol is usually backed by a schedule stating the dimming method: leading edge, trailing edge, 0-10 V or DALI. The reader should check that every luminaire on the dimmed group is dimmable by that method.
The plan mark does not state the dimming technology or minimum load. A rotary or push dimmer looks the same on the plan.
How to read it
- Check the dimming method in the schedule.
- Confirm every luminaire in the group is compatible.
Information to show or reference
- State dimming method and rated load.
- Link to the dimmed luminaire group.
- Note minimum load for LED circuits.
A distinction that matters
A one-way switch has no variability mark; the dimmer adds continuous control of light output.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
IEC graphical symbols for diagrams
IEC graphical symbol context; independently drawn here.
Autodesk IEC-60617 preview: Operating-device and function qualifiers
Public IEC-oriented qualifier family showing how adjustability is added to a base symbol.
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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