Why does a breaker trip? What to know without panicking

When a breaker trips, the first instinct is to flip it straight back. But it cut the circuit to protect it; switching it on again and again without knowing why can make things worse.

The usual causes

• Overload: too many powerful appliances (oven, heater, washing machine) running on one circuit at once.
• A faulty appliance: a leak or short circuit inside an appliance trips the breaker.
• A wiring fault: a loose connection, or a crushed or aged cable.
• Damp: water getting into sockets and fittings in bathrooms, balconies or outdoors.

What you can safely do

1. Unplug the appliances on that circuit.
2. Switch the breaker back on once.
3. If it won't stay on, or trips again straight away, don't force it; call an electrician.

What not to do

• Don't tape the breaker or hold it on any other way.
• Don't have a bigger breaker fitted "so it stops tripping"; the cable overheats and becomes a fire risk.
• If there's a burning smell, smoke or a hot socket, touch nothing; if there's smoke, call 112.

A breaker that trips often is a sign of a problem that needs to be found with proper testing.