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U = R · I·P = √3 · U · I · cos φ·DS/HD 60364 series·RCBO 30 mA · characteristic B/C/D·κ ≈ 56 (Cu) · 35 (Al)·Voltage drop ≤ 3 %/5 %·A reference work in Danish·
U = R · I·P = √3 · U · I · cos φ·DS/HD 60364 series·RCBO 30 mA · characteristic B/C/D·κ ≈ 56 (Cu) · 35 (Al)·Voltage drop ≤ 3 %/5 %·A reference work in Danish·

Electrical
installation,
explained.

A complete Danish reference work on electrical installation — from Ohm's law and voltage drop to cable sizing, circuits and protection against shock and overcurrent. Read the articles. Use the calculators. Ask the assistant. Same account as technical insulation.

13

Calculators

27

Articles

Questions

Fig. 01

5-core cable cross-section (L1·L2·L3·N·PE), a simple circuit U = R·I, an analogue 230 V meter and the lightning bolt for voltage. Copper marks the live conductors.

Read, calculate, choose — or ask.

Otte værktøjer fra opslag til installation — for lærlinge, montører og installatører.

Work it out.

Enter the length, current and conductor material — find the smallest cross-section that keeps the voltage drop below your limit, and the nearest standard cross-section. Then verify the current-carrying capacity and short-circuit performance against DS/HD 60364-5-52.

Open calculators

Example · Cable cross-section by voltage drop

Single-phase · 230 V

DS/HD 60364-5-52
Current20 A
Length (one way)35 m
Conductor materialCopper (κ ≈ 56)
Permitted voltage drop5 %
Calculated ΔU≈ 2,7 % ved 4 mm²
Selected standard cross-section4 mm²

How it looks craftsmanship.

Tre klassiske arbejdsgange fra faget — tegnet som blueprint: transformergruppe, motorstarter og belysningsplan.

  • Transformer group main connections

    The electrician connects the transformer group's primary and secondary windings to the terminal box — with main switch, blue neutral conductor and green-yellow PE conductor to the earth electrode.

  • Motor starter — direct-on-line (DOL)

    The electrician connects a 3-phase motor with contactor: the power circuit carries current from the panel through fuse to the motor winding, while the control circuit with start, stop and thermal relay controls the coil.

  • Lighting plan with isolux curves

    The electrician places luminaires in a grid over the workshop and draws isolux curves so each work surface reaches the desired lighting. Lux levels are indicative — actual lux is calculated separately.

One question
in Danish.

The AI assistant can size cables, explain protection, calculate power and help with real-world cases in electrical installation. Write to it as you would to a colleague.

Find a school nær dig.

Electrician is offered at 24 Places that are particularly assessed: edges, corners, joints, seams, and under furniture in the country. The list is informational — always check the latest and complete offering on the Education Guide's vocational education map.