What it does
Each tool follows the rules of the standard you pick, so the numbers on screen match the numbers on your paperwork.
Ready when you are — even with no signal
Basements, switch rooms, new estates — the places where the Wi-Fi drops out are exactly where you need the numbers. Toptronic® Assistant runs fully offline on any Windows 10 or 11 laptop.
Download the installer Verify the SHA-256 hashFree to try · no account, no subscription · 67 national wiring standards included.
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.
Power factor correction
Size the capacitor bank in kVAR to hit a 0.95 or 0.98 target — and see the line current fall.
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.
Ghana L.I. 2008 check
New in b058 — dwelling checks per Ghana's Electrical Wiring Regulations 2011: 230/400 V 50 Hz, 30 mA RCD ≤40 ms, ring final 32 A / 2.5 mm² ≤100 m², IEC colours.
Oman 3-phase colours fixed
b058 correction — Oman OES-4 three-phase now shows the IEC set (brown/black/grey) instead of the US-style set.
Nigeria NESIS check
Ring and radial socket rules, black-neutral colour table and ELCB requirements straight from NESIS 2015.
Bahrain EWA Wiring Regulations check
Dwelling checks per Bahrain's EWA Electricity Wiring Regulations (BS 7671:2018 basis): 230/400 V 50 Hz, harmonised colours with 3-phase brown/black/grey, 30 mA RCD on socket circuits, BS 1363/type G sockets.
Brunei PBD IEC 60364 check
New in b061 — dwelling checks per Brunei's PBD IEC 60364: 240/415 V 50 Hz, harmonised colours with 3-phase brown/black/grey, 30 mA RCD on socket-outlet circuits, BS 1363/type G sockets.
Peru CNE-U 2011 check
New in b066 — dwelling checks per Peru's Código Nacional de Electricidad — Utilización (CNE-U 2011, NEC-derived): 220/127 V 60 Hz single-phase and 220/380 V three-phase, red/black/white earthed colours with neutral-bonded earthing, 30 mA RCD on socket circuits, type A & NEMA 5-15 sockets.
Colombia RETIE 2013 check
Recent — installation checks per Colombia's Reglamento Técnico de Instalaciones Eléctricas (RETIE 2013, Resolución 9 0708 MME): 110/220 V 60 Hz, IEC-style colour coding, RCD protection rules and Colombian socket types.
Trinidad & Tobago TTS 171 check
New in b071 — installation checks per Trinidad and Tobago’s TTS 171 Part 1:2015: 115/230 V 60 Hz, 200 V wild-leg delta identified blue, NEMA 5-15/5-20 sockets, 20 A branches on 2.5 mm², voltage drop ≤ 2.5 %, and the earth-leakage breaker rule.
Egypt ECP 101 check
Egypt's ECP 101 (Egyptian Code of Practice for low-voltage installations) joins the standard checks (b070): 230/400 V 50 Hz supply, RCD protection tiers and colour conventions, cited clause by clause.
Jamaica JS 316:2018 check
New in b069 — installation checks per Jamaica’s JS 316:2018 (the NEC application document from the Bureau of Standards Jamaica): 110/220 V 50 Hz, GFCI per §210.8 with the kitchen 1800 mm relaxation, dwelling AFCI not adopted (§210.12(B)), 3 %/5 % voltage drop, range-neutral ≥ 4 mm², and the black neutral (§200.6(A)).
Costa Rica CECR check
New in b068 — installation checks per Costa Rica's Código Eléctrico (CECR = RTCR 458:2011, NEC 2020 Spanish + national Adenda): 120/240 V 60 Hz, NEC GFCI rules, dwelling AFCI derogated by Decreto 43418-MEIC, 220.14(M) social-housing load rules.
RSIUEE Angola check
New in b072+ — dwelling checks per Angola's Decreto-Lei n.º 740/74 (RSIUEE, the legacy Portuguese LV regulation still applicable) with an IEC 60364 / RTIEBT practice layer: 220/380 V 50 Hz, type C/F (Schuko) sockets, IEC 60445 colours, 30 mA RCD practice on socket and wet circuits.
Adiabatic Check calculator
New in b080 — the fault-withstand check: S = I√t / k per IEC 60364-4-43 cl. 43.1. Enter the fault current and clearing time, pick PVC or XLPE and copper or aluminium, and get the minimum cross-section, a pass/fail verdict on the installed size and the margin in percent.
Grouping & derating
New in b081 — IEC 60364-5-52 Table B.52.17 grouping factors and NEC 310.15(C)(1) adjustment, combined with ambient correction: the real derated ampacity Iz×Ca×Cg, per standard.
Croatia HRN HD 60364 check
New in b081 — dwelling checks per Croatia’s HRN HD 60364 series under Technical Regulation NN 5/10: 230/400 V 50 Hz, 30 mA RCD practice, IEC colours.
Earth Resistance calculator
New in b078 — the calculator every TT installation needs: enter the RCD rating (10–500 mA) and the measured Ra, get the IEC 60364-4-41 cl. 411.5.3 verdict, the 50 V touch-voltage limit, and the highest RCD rating that keeps you compliant.
Conduit Fill calculator
New in b077 — the Calculators section grows again: enter cable count and size, choose the conduit diameter, and get the IEC 60364-5-52 space-factor verdict plus the smallest compliant conduit size. Calculators are now ordered by how often each standard calls for them.
Philippines PEC — audited
New in b076 — the Philippines check now follows PEC Art. 2.10.1.8(a)(1)–(8) verbatim, quotes the UL 943 Class A range, adds the bedroom AFCI rule and flags later-edition items as unverified.
Malta S.L. 545.24 check
New in b075 — dwelling checks per Malta’s Electrical Installations Regulations (S.L. 545.24), which pull in BS 7671 by reference: 230/400 V 50 Hz, a 30 mA RCD on every sub-circuit, main double-pole switch-fuse ≤ 60 A, BS 1363 type G sockets, TT earthing practice and the overvoltage-protector rule.
Serbia Pravilnik 53/88 check
New in b065 — dwelling checks per Serbia's Pravilnik o tehničkim normativima za električne instalacije niskog napona (Sl. list SFRJ 53/88, amended SRJ 28/95; IEC 60364-modelled, SRPS HD 60364 standards layer): 230/400 V 50 Hz, art. 11 green-yellow PE / light-blue neutral, 30 mA RCD on socket and wet circuits, type C + F (Schuko) sockets.
Morocco NM C 15-100 check
New in b063 — dwelling checks per Morocco's NM 06.1.100 (NM C 15-100, IMANOR adaptation of IEC 60364): 230/400 V 50 Hz, harmonised IEC 60445 colours, 30 mA RCD on socket and wet circuits, French/Arabic labelling.
Tanzania TZS 3201 IEC 60364 check
New in b062 — dwelling checks per Tanzania's TZS 3201 series (TBS adoption of IEC 60364, compulsory per GN 164/2023), required by the EWURA Electrical Installation Services Rules 2022: 230/415 V 50 Hz, harmonised colours with legacy red/yellow/blue warning, 30 mA RCD, type D & G sockets.
Uganda IEE Regulations 2017 check
New in b059 — dwelling checks per Uganda's IEE Regulations 2017: 240/415 V 50 Hz, legacy UK red/black colours in common use with an IEC-stock warning, 30 mA RCD on socket circuits ≤32 A, BS 546/type G sockets.
Three-phase colour codes
Phase, neutral and protective conductor colours per country — current and older schemes side by side for panel and machine work.
Site in your language
The web site now speaks your language — pick from 14 languages in the top-right Language menu; the choice is remembered. Plus the Angola RSIUEE DL 740/74 dwelling check (b072).
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 ασφάλεια 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 and an otomatik sigorta in Turkey — and the interface follows suit.
Interface languages include: English · Français · Deutsch · Español · Português · Italiano · Nederlands · Ελληνικά · Magyar · Polski · Türkçe · Română · plus more added with every build — pick yours in Settings, no reinstall.
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) · L.I. 2008 (Ghana) · IEE Regulations 2017 (Uganda) · SEPA 3000 (Singapore) · IEC 60364 (International) · PUIL 2011 (Indonesia) · JIS C (Japan) · NOM (Mexico) · IRAM (Argentina) · NBR 5410 (Brazil) · TTBS TTS 171 (Trinidad and Tobago) · RSIUEE DL 740/74 (Angola) · Egyptian Code (Egypt) · SEC (Saudi Arabia) · DEWA (Dubai, UAE) · Sri Lanka SLS (Sri Lanka) · NZS 3000 (New Zealand) · Pravilnik 53/88 (Serbia) · NM C 15-100 (Morocco) · TZS 3201 (Tanzania) · GB standards (China) · IS 732 (India) · MS 1525 / IEC (Malaysia) · 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?
67 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 for the full picture.
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-0.1.79-b081-x86_64.msi SHA256
Build 080 (current): 6bbfaaf0d7997f2cf3f3fa6394778a98d2f1f521413e5cc514c72183e40f7fbf
Build 079 (previous): 23082057f557a4f846b1ca0ee757369e6e98770b8475f897a10fa728e068dbfb
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.
Feedback
Found something that doesn't add up, or wish the app did something it doesn't? Tell us — it's the same channel the app's Help > Send Feedback uses, straight to the development team.
About Toptronic
Toptronic® Assistant is built by Toptronic® Ltd, designing electrical test equipment to standards since 1990. 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 electronics engineer. Toptronic® Assistant aims to be a toolbox that keeps getting better — shaped by your feedback and suggestions, one build at a time.
[email protected] — write directly; mail is read and answered.