What to Do When Your Circuit Breaker Keeps Tripping

First: stay safe

If you smell burning, see scorch marks or a breaker is hot to the touch, leave it off and call an electrician. Don't keep resetting it.

Why breakers trip

1. Overload: too many appliances on one circuit (oven + kettle + heater).
2. Contracted power exceeded: in Portugal the main breaker (disjuntor geral) trips when you go over your contracted kVA.
3. Faulty appliance: an element or motor leaking current to earth trips the RCD (diferencial).
4. Moisture: water in outdoor sockets, lights or junction boxes, common after rain.
5. Wiring fault: loose connections or damaged cables.

Step-by-step check

1. Note which switch trips. The main breaker, the RCD or one circuit breaker?
2. Unplug everything on the affected circuit.
3. Reset the switch. If it stays on, plug appliances back in one at a time. The one that trips it is the culprit.
4. If it trips with nothing plugged in, the fault is in the wiring or a fixed appliance (water heater, oven, lights). Call an electrician.
5. If the main breaker trips at peak times, you may be exceeding your contracted power. Spread out usage or ask your energy supplier about increasing it.

When to call an electrician

• It trips repeatedly with nothing plugged in
• It trips after rain
• Any burning smell, buzzing or heat at the panel
• Your panel has old fuses or no RCD

Diagnosis usually costs €60–€150.