BS 7671 calculations with the working shown.For UK electricians and plant engineers. Free, no account.

Every engine computes transparently from statutory equations with complete step-by-step mathematical working. Zero paywalls, zero ads, plant-room ready.

17Visual labs29Sizing engines (33 total tools)29Field guides24/7Curated news

An actively growing engineering workstation built by a working UK electrical engineer. New 3D models and sizing engines added regularly.

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The Visual Lab

Interactive 3D physics & electromagnetics
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Interactive 3D electromagnetics and machinery. Part of a growing first-principles suite with new industrial modules continuously in development.

Calculators & Sizing Engines

First-principles engineering mathematics
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Every tool computes transparently from BS 7671 equations and shows its step-by-step working. Our calculation deck is continually expanded to cover new industrial and domestic scenarios.

On-Site Field References & Practical Toolkit

Field-ready lookup decks, defect finders & print sheets
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Engineered for rapid site verification on phones and tablets. Fast lookup tables, 1-click clipboard export for inspection software, and print-ready A4 checklists.

Technical Guides & Field Manuals

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Practical engineering workflows, testing procedures, and statutory regulatory breakdowns. 29 field guides live, with new compliance topics published regularly.

Regulatory & Technical Briefing

Live statutory updates, BS 7671 transitions, and technical alerts
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BS 7671:2018+A4Transition periodTransition window active: 4 days remaining in Orange Book transition
EXECUTIVE STATUTORY BRIEFING

Live DNO cut-out on a pre-tender walk-round is still a Regulation 14 event

Mandatory duties under EAWR 1989 Reg 14, cut-out isolation procedures, and 4 days remaining in the BS 7671:2018+A4:2026 Orange Book transition window.

✓Reg 14 Absolute Duty: No live work unless unreasonable in all circumstances.
✓Cut-Out Seal Integrity: DNO equipment isolation requires approved procedure.
✓Transition Window: Dual-certification acceptable until deadline.
Technical - Codebreakers #126: Concealed Kitchen Wiring Behind Tiled Metal Plate
Technical

Codebreakers #126: Concealed Kitchen Wiring Behind Tiled Metal Plate

Key Takeaway: Unenclosed wiring and joint boxes concealed behind metal wall plates require immediate inspection for accessible live conductors and mechanical protection.

NAPIT technical analysis of an installation where electrical wiring was found concealed behind a tiled metal plate in a domestic kitchen. Highlights the requirement for proper enclosures, accessible junctions, and IP protection under BS 7671.

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