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Size it, spec it, check your work

Twenty calculators that show their method, eighteen guides that answer one question each, and open boards for practising one-lines, power PODs and rack elevations.

Equipment models
Interactive equipment models 32 procedural 3D models across the practice tools
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Three ways in

Most people arrive with one of three questions. Each of these opens onto the rest.

Work it out

Twenty calculators — voltage drop, transformer sizing, arc-flash incident energy, cable ampacity, fault current — each showing the method, not just the answer.

Understand it

Eighteen guides, each written to answer a single question — how a nameplate reads, what an arc-flash boundary is, why PUE lies to you — plus a plain-language glossary.

Practise it

Open boards for laying out real equipment — a one-line, a packaged power module, a rack elevation — with the result checked against sizing, load and code rules as you build.

Reference by sector

Five sectors of power equipment

Each opens onto the guides, reference specifications and standards for that sector.

Start somewhere

Not sure what you need yet?

The tools hub lists everything on the site in one place — every calculator, every practice board, the glossary quiz and the PCB builder. Nothing needs an account.

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How this is made

Where the numbers come from

Every figure on the site carries a basis, and the methodology page sets out how each is derived, what it is good for, and where it should not be relied on.

Read the methodology