Electrical Wiring Simulator & Trainer
Real Components • True Multicore Cables • SWG & Amp Sizing • Live Faults — Simulate • Explore • Practice • Quiz
Σ Live equations — from the current circuit
1 Overview
The Electrical Wiring Simulator is a hands-on domestic installation trainer. You place realistic components — a consumer unit with breakers, one-way and two-way wall switches, 13 A sockets, ceiling roses, lamp holders and household appliances — onto a workbench, then wire them together with true multicore cables. Each cable end fans out into its individual coloured conductor nodes (brown Line, blue Neutral, green-yellow Earth), exactly like stripping a real cable. Turn the power on and the circuit comes alive: lamps light, fans spin, breakers trip and overloaded cables overheat.
It is built for electrical trainees, vocational students and instructors who want to practise wiring safely before touching real conductors.
2 Getting Started
- Add a component: tap any item in the Components or Household Loads palette and it drops onto the board. Drag it to position.
- Add a cable: in the Cable Builder pick a core type (e.g. Twin & Earth) and a size, then press Add Cable. The cable appears with coloured conductor nodes at each end.
- Wire it up: drag a conductor node (the small coloured dot at a cable tip) onto a component terminal to make a connection.
- Join two wires: drag one conductor tip onto another conductor's tip — an insulator connector appears over the splice. Click that connector (or tap either connected conductor) to open the joint again.
- Energise: press Power ON. Toggle switches by tapping them.
- Edit tools (bottom of the canvas): Undo, Redo, Duplicate, Rotate cable, Delete and Clear.
- Left panel: Components, Household Loads, Cable Builder and the Selected-item inspector are grouped into collapsible sections — click a heading to fold it away.
- Keyboard: Ctrl+Z undo, Ctrl+Shift+Z (or Ctrl+Y) redo, Ctrl+D duplicate, R rotate a selected cable, Delete delete (Shift+Delete clears the board), P power, G generate.
- Shortcut: press Generate to auto-build a correct circuit you can study or modify — optionally with a hidden fault to diagnose.
3 Simulate Mode
Simulate is the wiring workbench. The toolbar gives you Power, Generate, a 230 V / 120 V supply toggle, Delete and Clear. The readout badges show supply voltage, total load current, how many loads are live, and overall status. The fault strip lists any wiring problems it detects:
- Overloaded cable — current exceeds the cable's rating; it heats up and, if the protective device is too big, catches fire.
- Breaker tripped — overload (thermal) or a Line-Neutral short (instant magnetic trip).
- Missing earth — a metal-bodied (Class I) appliance with no protective earth is a shock hazard.
- Switched neutral — the switch breaks the neutral instead of the line.
- Wrong plug fuse — a fuse bigger than the flex it protects.
4 Cable Builder & SWG Sizing
Real installations use multicore sheathed cable, not loose wires. The Cable Builder lets you choose:
- Core type: 2-core (Line + Neutral), Twin & Earth (+ bare earth), 3-core + earth (for two-way switching), and 2-core / 3-core flex for appliances.
- Size: metric mm² (1.0, 1.5, 2.5, 4, 6, 10) or the equivalent SWG number, each showing its current rating. Pick a size whose rating exceeds the load current from I = P / V.
The golden rule the simulator grades against is Iload ≤ Idevice ≤ Icable: the fuse or breaker must be bigger than the running current but smaller than the cable rating.
5 Explore Mode
Explore organises the theory into four categories: Wire & Cable (SWG, mm², ratings, core colours), Components (switches, sockets, consumer unit, FCU), Protection & Safety (MCB, RCD, earthing, fuses) and Circuits (one-way, two-way, ring/radial, loop-in). Each card has a clear explanation and, where relevant, a worked example.
6 Practice & Quiz
Practice mode mixes calculation problems (find the load current, pick the cable, size the fuse) with wiring-choice questions. Type or choose your answer, press Check, and read the worked solution. Your score is tracked.
Quiz mode presents 5 questions on cable sizing, colours, switching and protection, then gives a score with a star rating and a per-question breakdown.
7 Key Formula & Safety Note
Every current in the tool comes from I = P / V. Example: a 2000 W heater at 230 V draws 2000 / 230 ≈ 8.7 A, so a 1.5 mm² flex (16 A) with a 13 A plug fuse is safe. The same heater on a US 120 V supply would draw 16.7 A — nearly double — which is why the 120 V toggle recomputes every current.
Safety: all current ratings here are teaching nominals. Real installations must be sized and derated per BS 7671 / local code. This simulator is an educational aid, not a substitute for a qualified electrician.
A Realistic House Wiring Simulator for Electrical Training
This electrical wiring simulator lets you build real domestic circuits the way an electrician does: with recognisable switches, sockets, lamps and a consumer unit, joined by genuine multicore cables rather than abstract lines. You choose the cable's core configuration and size, wire each coloured conductor to a terminal, switch on the supply, and watch the installation behave — lamps light, appliances draw current, breakers trip and undersized cables overheat.
Sizing Cable by SWG Number and Amp Load
The heart of safe wiring is matching the cable to the load. Every current follows I = P / V, so a 3 kW kettle on a 230 V supply draws about 13 A. You then pick a cable whose current rating exceeds that value. The Cable Builder shows both the metric mm² size and the equivalent SWG (Standard Wire Gauge) number with its amp rating, so you can size a conductor by gauge and loading exactly as required in the field.
| Cable | Typical use | Rating (approx.) |
|---|---|---|
| 1.0 / 1.5 mm² T&E | Lighting circuits (6–10 A MCB) | ~16–20 A |
| 2.5 mm² T&E | Socket circuits (radial / ring) | ~20–27 A |
| 6 / 10 mm² T&E | Cooker, shower, water heater | ~40–64 A |
| 0.75 mm² flex | TV, lamp, small appliance | ~6 A (≈1400 W) |
| 1.25 mm² flex | Kettle, iron, microwave | ~13 A (≈3000 W) |
True Multicore Cables, Not Line-by-Line Wires
Unlike a schematic drawing tool, this trainer models cables the way they exist in a wall: a single insulated sheath containing several conductors. Pick a 2-core cable for a double-insulated (Class II) fitting, twin-and-earth for fixed lighting and sockets, or 3-core + earth for two-way switching. Each cable end shows its conductors as separate coloured nodes — brown Line, blue Neutral, green-yellow Earth — and the simulation engine energises each conductor independently, so a swapped or missing core behaves exactly as it would in reality.
Switching, Sockets and the Consumer Unit
Wire a simple one-way light switch that breaks only the line, build a two-way staircase circuit with COM/L1/L2 terminals and a 3-core strapper, or lay out a ring or radial socket circuit. The consumer unit models a main switch, a busbar and individual MCBs (6–40 A) with RCD protection, so you can see which breaker protects which circuit and how a 30 mA RCD guards against electric shock.
Learning From Faults
Getting it wrong is where the learning happens. Overload a cable and it glows with heat; leave the protective device oversized and it catches fire instead of tripping. Forget the earth on a metal-bodied water heater and the tool flags a shock hazard. Fit a 13 A fuse on a lamp flex and it warns that the fuse can no longer protect the cable. The rule you internalise is Iload ≤ Idevice ≤ Icable.
Who Uses This Simulator?
This tool is used by electrical and vocational students learning domestic installation, apprentices preparing for wiring assessments, and instructors demonstrating switching, cable selection and circuit protection without the risk of live conductors. It suits UK/IEC-style 230 V practice (as used across the UAE) with a US 120 V comparison built in.
Explore Related Simulators
If this Electrical Wiring Simulator helped, try our Ohm's Law Simulator, Resistor Colour Code tool, Logic Gates Simulator, and PLC Ladder Logic Simulator for more hands-on electrical practice.