Five common mistakes in electrical installations

1. Breakers sized by the socket, not by the cable

A 16 A breaker on a 1.5 mm² cable is a problem waiting to happen. The breaker protects the cable, not the appliance: size it by the conductor cross-section.

2. Earthing that was never measured

A yellow-green conductor is not a guarantee. Continuity and earth resistance are measured and written into a test report — otherwise the RCD may not trip when it must.

3. One circuit for the whole kitchen

Oven, hob, dishwasher and fridge on a single circuit means repeated tripping and a warm cable. A kitchen needs at least two socket circuits, separate from lighting.

4. Junction boxes buried in plaster

Every joint must stay accessible. A plastered-over junction box becomes, at the first fault, a reason to break the wall.

5. No diagram at handover

Without a single-line diagram and labels on the panel, the next intervention starts with an hour of guessing. Ask for the diagram at handover — it is part of the deliverable.