Electrician/Calculators

Work it out.

Calculators tailored to electrical work: understand the fundamentals, size the cable, work out power and load, and see the economics. Enter your own values — the result updates live.

AStep

The basis

Start here: Ohm's law and power — the relationship between voltage, resistance, current and power.

Ohm's law & power

Voltage, resistance, current and power

Transformer ratio

Voltage, current, and transformation ratio

BStep

Cable & voltage drop

Size the cable: calculate the voltage drop and find the smallest cross-section that stays within the limit.

Voltage drop

Voltage drop over a cable run

Cable cross-section

Minimum cross-section based on the permitted voltage drop

CStep

Power & load

Calculate power in single-/three-phase systems and add several circuits together with a diversity factor.

Three-phase power

Active, apparent and reactive power

Group load & simultaneity

Design power and current for multiple groups

Load current IB

Current for a known power — 1-phase, 3-phase or motor

Motor starting current

Inrush factor and peak current at start

DStep

Protection & verification

Kontrollér sikkerheden: tåler lederen kortslutningen (K²S² ≥ IK²·t), og vælg RCD/HPFI så berøringsspændingen holder i TT-systemet.

Short-circuit check

Thermal capacity K²S² ≥ IK²·t

RCD / HPFI in TT system

Rated tripping current from earth resistance

EStep

Finances

Convert power and run time into kWh and cost using your own electricity price.

Energy consumption & cost

kWh and cost for a load over time

FStep

Lighting design

Dimension lighting systems according to EN 12464-1: find lux on the work surface or number of lamps to reach your target lux.

Lighting — lux on the work surface

Design of lighting systems according to EN 12464-1

VStep