Drag symbols onto the canvas, connect them, label them, then export as PNG or PDF — free, no login required.
Saved! Shareable link:
What Is a Single Line Diagram?
A single line diagram (SLD), also called a one-line diagram, represents a three-phase power system using a single line and standardized symbols instead of drawing every phase conductor. Engineers use SLDs to show how power flows from a utility or generator source, through transformers, buses, circuit breakers and protection devices, down to individual loads — without the clutter of a full multi-line schematic.
How to Use This SLD Generator
Drag a symbol from the left palette (generator, transformer, breaker, bus, load, etc.) onto the canvas to place it — or tap it to drop it into the visible area.
Drag any placed component to reposition it. Tap it without dragging to rename its label in the properties panel.
Click a small connector dot on one component, then a connector dot on another, to draw a wire between them.
When your diagram is ready, export it instantly as a PNG image or a print-ready PDF.
Use "Save & Share" to generate a link you can send to colleagues or come back to later.
Frequently Asked Questions
Is this SLD generator free? Yes, it's completely free with no sign-up required.
Can I edit a saved diagram later? Yes — open your shareable link and continue editing; saving again updates the same diagram.
What symbols are supported? Utility source, generator, transformer, bus bar, circuit breaker, fuse, isolator, protection relay, motor, load, capacitor bank, energy meter, earth/ground and switch.