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Voltage Drop Calculator

VD = k × I × L × (R cos φ + X sin φ)

Single-phase, three-phase and DC voltage drop in sq mm or AWG under 15 national codes (IEC, NEC, BS 7671, SP 30 and more), with your own cable data if you have it.

Handbooks, apps, calculators and digital tools made by EngiLoop for engineers, electricians, students and curious builders.

Illustration of a dark hardback handbook with a teal circuit trace on its cover.
PDF handbook Coming soon

Electrical Design & Calculation Handbook

A consultant-grade design handbook that works through electrical calculations in a consistent, step-by-step format, from inputs to checked result.

Illustration of a spreadsheet grid with a highlighted cell and a calculator beside it.
Excel workbook Coming soon

Design & Calculation Master: Excel Toolkit

The master Excel workbook for the Design & Calculation Master series: structured calculation sheets that follow the handbook step by step.

Illustration of a house with an electrical panel, a capacity gauge and an EV charger outside.
Android app Coming soon

PanelReady

A home electrical capacity planner that helps homeowners and electricians check whether an existing service can take an EV charger and other new loads.

Price: Price to be announced

View product : PanelReady
Illustration of a phone showing a circular teal timer ring.
Android app Coming soon

Screen On Timer – Keep Awake

A simple Android utility that keeps your screen awake for as long as you choose, then hands control back to your normal screen timeout.