What it does
Each tool follows the rules of the standard you pick, so the numbers on screen match the numbers on your paperwork.
All the tools
Wire sizing
Ampacity with correction factors, per your national standard's tables.
Breaker sizing
Continuous-load rules and standard ratings, with circuit-level checks.
Voltage drop
Per-standard limits for single-phase and three-phase runs.
Power & current
Single- and three-phase current, kVA, and transformer secondary current.
Motor full-load current
NEC 430.250 tables plus overload and short-circuit protection guidance.
Lighting & energy
Lumen and fixture counts, with daily and monthly energy cost estimates.
Wiring colour codes
Conductor colours by country — single-phase, three-phase and DC views.
National standard checks
Dwelling-branch compliance with cited clause numbers for every standard.
Reference
Formulas, code sections and quick-reference cards for every supported standard.
Works offline
No account, no telemetry, no external services. Everything runs on your machine.
Kuwait MEW R-1 check
Dwelling-branch compliance against Kuwait's MEW Regulation R-1, with cited clauses.
Sri Lanka Wiring Regulations
Standard checks per Sri Lanka's wiring regulations (b055).
Romania I7-2011 check
New in b056 — dwelling checks per I7-2011 (2023 amendments): RCD tier incl. lighting, AFDD.
Oman OES-4 check
New in b057 — circuit checks per Oman's OES-4 (2019): 240/415 V supply, 30 mA RCD on socket circuits, BS 1363 practice.
Nigeria NESIS check
Ring and radial socket rules, black-neutral colour table and ELCB requirements straight from NESIS 2015.
Three-phase colour codes
Phase, neutral and protective conductor colours per country — current and older schemes side by side for panel and machine work.
Send Feedback
Help > Send Feedback in the app — routes your message to the right reviewer with useful context.
Countries and languages
The app works in your language and applies the wiring rules of your country — one switch in Settings, no reinstall. Countries covered include:
The app uses the terms you know: a circuit breaker is a disjoncteur in France, a Sicherungsautomat in Germany and Austria, an ασφάλειας in Greece, a megszakító in Hungary, an automaat in the Netherlands, an interruttore in Italy, a disjuntor in Brazil and Portugal, a wyłącznik nadprądowy in Poland, an otomatik sigorta in Turkey — and the interface follows suit.
Supported standards include
NEC (USA) · CE Code (Canada) · SANS 10142 (South Africa) · BS 7671 (UK) · I.S. 10101 (Ireland) · NF C 15-100 (France) · DIN VDE 0100 (Germany) · NEN 1010 (Netherlands) · RGIE/AREI (Belgium) · MSZ HD 60364 (Hungary) · OVE E 8101 (Austria) · ČSN 33 2000 (Czechia) · AS/NZS 3000 · SFS 6000 (Finland) · BEK 1082 (Denmark) · SS 436 40 00 (Sweden) · NEK 400 (Norway) · NIN (Switzerland) · REBT (Spain) · RTIEBT (Portugal) · I7-2011 (Romania) · NESIS 2015 (Nigeria) · OES-4 (Oman) — plus standards across Asia-Pacific, the Middle East and Latin America.
Frequently asked questions
Does the app need an internet connection?
No. Everything runs locally on your Windows machine — calculators, colour-code charts and standard checks included. The only online step is downloading the installer itself.
Which countries and standards are covered?
50 countries across Europe, the Americas, Asia-Pacific, Africa and the Middle East, each with its own national wiring standard — NEC, BS 7671, NF C 15-100, I.S. 10101, AS/NZS 3000 and many more. See the lists above.
Do I need an account or subscription?
No. One download, no sign-up, no recurring fees. Installing a new build replaces the previous one and keeps your settings.
What languages does the interface support?
The app works in your language and uses local trade terminology — pick both in Settings, no reinstall needed.
Windows shows a SmartScreen warning when I run the installer. Is that normal?
Yes, for now. The installer isn't code-signed yet, so Windows shows a reputation warning for first-time downloads. Verify the file's SHA-256 hash on our Security page, then click "More info" and "Run anyway".
Does it collect any of my data?
It doesn't. No telemetry, no analytics, nothing leaves your machine. This website sets no tracking cookies either — the footer's IP line is fetched on demand and never stored.
Security & verifying your download
After downloading, run this in Command Prompt or PowerShell and compare the output with the value below:
certutil -hashfile toptronic_assistant-0.1.57-b057-x86_64.msi SHA256
Build 057 (current): 9f275cb0eeeab0c5c6f370fbc96c5041586c4067e17bf6bf664ca8e685d8994b
Build 056 (previous): a661b5f1294ab51d75bbd1ee3ad10ffa6ca1fee4dd8be0629c0567dddb838d1e
Build 055 (previous): b9740ebc8fcd73b34d160809397ff4485ce67a3e6edb59989170cb13234385cb
About the SmartScreen warning. The installer is not yet code-signed, so Windows may show a blue "Windows protected your PC" dialog on first run. That is a reputation warning for small-vendor software, not a virus detection. Verify the hash above, then click "More info" and "Run anyway". Once a code-signing certificate is in place, the dialog stops appearing. The app itself makes no network connections at runtime — if it ever tries to, that's not our build.
About Toptronic
Toptronic® Assistant is built by Toptronic® Ltd, a small software company that works alongside practising electricians rather than at arm's length from them. Every calculator and standard check starts from a real job — a panel to size, a cable run to justify, an installation to sign off — and ships only when it matches the national standard it claims to follow.
The company was founded by Jacques, an electrical engineer who spent years on sites and in switch rooms before writing a line of code. Toptronic® Ltd remains independent and self-funded: no investors, no subscription treadmill — just a toolbox that keeps getting better, one build at a time.
jacques@toptronic.com — write directly; mail is read and answered.