UBUElectricalBasic

A free, open-source teaching tool for undergraduate electrical engineering. Three modes in one app:

• Schematic — IEC 60617 motor-control diagrams (MCB, contactor, overload, push-button NO/NC, pilot lamps, 3-phase motors) with a live simulator: wires glow, lamps light, motors animate.
• Circuit Analysis — DC nodal/mesh/superposition/Thévenin walkthroughs with worked examples, AC mode with H(s) / Bode / phasor / step response / pole-zero / power, and balanced 3-phase analysis.
• Block Diagram — linear SISO control-system reduction with Mason's gain formula, root locus with the full RLocusGui-style rule walkthrough (asymptotes, real-axis segments, break points, ω-axis crossings, etc.), and a P/I/D + plant playground.

Every mode shows the moves, not just the result: step-by-step prose in Thai + technical English, with quantity-coloured math (V = blue, I = emerald, R = amber, G = sky, H = fuchsia, Δ = indigo, ω = cyan, …).

Built at the Faculty of Engineering, Ubon Ratchathani University for the 1306 211 Electrical Engineering Workshop and 1306 210 Electrical Engineering Laboratory I courses, plus the linear-control-systems course.

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Install

Windows

1. Download the latest UBUElectricalBasic-Setup-*.exe from the Releases page.
2. Double-click. SmartScreen may warn "publisher unknown" — click More info → Run anyway (the installer is unsigned for now).
3. Choose an install folder, pick whether to create Desktop / Start Menu shortcuts, and finish.
4. Launch from the shortcut. Fully offline.

Run in a browser (no install)

If you have Node.js 18+ installed:

git clone https://github.com/ThummarosR/ubu-electrical-basic.git
cd ubu-electrical-basic
npm install
npm run dev
# open http://localhost:5173

Or npm run build && npm run preview for a production build.

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Build the installer yourself

npm install
npm run dist
# output: release/UBUElectricalBasic-Setup-<version>-x64.exe

npm run dist re-generates the icon (scripts/build-icon.cjs from public/icon.svg), runs tsc -b && vite build, then packages with electron-builder --win nsis.

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Project structure

src/
  components/
    nodes/iec.tsx           ~70 IEC 60617 symbol descriptors + IECNode wrapper
    AnalysisPanel.tsx       Right-side DC/AC/3φ analysis panel
    BlockDiagramPanel.tsx   Right-side block-diagram panel (Mason + plots)
    RootLocusPlot.tsx       Zoomable root-locus + rule walkthrough
    FormattedStep.tsx       Quantity-coloured math renderer
  lib/
    analyze/                Polynomial algebra, MNA solver, root finder, units
    blockdiagram/           Mason's rule, s-poly parser, SymExpr CAS-lite, RLocus rules
    examples.ts             Catalogue of example diagrams (JSON-backed for hand-tuned ones)
electron/main.cjs           Electron main process
scripts/build-icon.cjs      SVG → multi-resolution ICO

Tech

Vite + React + TypeScript; React Flow for the canvas; Tailwind CSS; Zustand for app state; Electron + electron-builder for the Windows installer; Vitest for the tests.

No backend, no telemetry, no network calls.

Tests

npm test         # one-shot
npm run test:watch

Currently 62 tests covering the polynomial parser, the SymExpr arithmetic, Mason's rule (including non-touching loop topologies), and the root-locus rules.

License

Apache License 2.0 — see LICENSE.

Copyright © 2026 Faculty of Engineering, Ubon Ratchathani University.

Acknowledgements

• The root-locus rule walkthrough is modelled after Erik Cheever's RLocusGui (Swarthmore College, 2007) — a long-time favourite for learning the textbook rules visually.
• IEC 60617 symbol layouts follow the conventions used in the 1306 211 Electrical Engineering Workshop and 1306 210 Electrical Engineering Laboratory I lab manuals at UBU Faculty of Engineering.