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Beginner🧭 Matches an in-app guided circuit

Two-Bulb Parallel Circuit

Wire two bulbs in parallel so each receives full voltage independently. This is how all household lighting and sockets are wired — one bulb failing or being removed has no effect on the other.

Guide review
Standards context
BS 7671:2018+A4:2026 · IEC 60364

Components Needed

Text Wiring Path

Live → MCB → Switch → Junction Box → Bulb A
                                        → Bulb B → Neutral

Schematic

L N MCB SW JB LAMP A LAMP B
Live (line) Neutral Current flow (simulated)

Steps

  1. 1Build the single-lamp circuit from Circuit 1.
  2. 2Add a Junction Box after the Switch.
  3. 3Place a second Bulb below the first.
  4. 4Wire the Junction Box output to both bulbs.
  5. 5Connect both Bulb Neutral ports back to the Neutral terminal.
  6. 6Press Run — both bulbs light at full brightness.
  7. 7Disconnect one bulb wire — the other stays on. That's parallel wiring.
Key insight

In a parallel circuit, every branch receives the full supply voltage. Adding more branches increases total current drawn — the MCB protects against overload if too many loads are connected.

⚠ Safety practice

These walkthroughs teach wiring logic in a simulator. Real installation work must be isolated, tested dead, and carried out by a competent person — in the UK, notified under Part P or done by a registered electrician.

Terms used here

Defined in the glossary — each one opens at its own entry.

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Build this circuit in the browser, inject a fault, and watch the protection respond.

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