Power Cut, Tripping RCD or Electrical Emergency? What to Do Next

In an electrical emergency, your first priority is safety: if there is fire, smoke or someone has had an electric shock, call 999. If your power has gone off, check whether your neighbours are affected. If they are, it is a network power cut and you should call 105. If it is only your property and the trip switch will not reset, or there are signs of burning, you need an emergency electrician.

This guide walks through the safe steps to take in the most common situations, and explains when to call your network operator and when to call us.

Step 1: Make the situation safe

• Fire or smoke from electrical equipment: leave the property and call 999. Never use water on an electrical fire.
• Someone has had an electric shock: don't touch them if they may still be in contact with the source. Switch off at the consumer unit if you can do so safely, then call 999.
• Burning smell, sparking or buzzing: stop using the affected socket or appliance. If it is safe to reach, switch off the main switch on your consumer unit.
• Water near electrics: if water is leaking through a ceiling light or onto sockets, switch off at the main switch if you can reach it without standing in water, and don't touch wet fittings.

Once everyone is safe, you can work out what kind of problem you have.

Power cut: what to do

Is it just you, or the whole street?

Look outside. Are streetlights and neighbouring homes dark? If so, the fault is almost certainly on the electricity network rather than in your home.

Call 105, the free national power cut helpline. In London, the East and the South East of England, this connects you to UK Power Networks, the distribution network operator responsible for the cables and substations that supply your home. They can tell you whether a fault has been reported and when power is expected back. It doesn't matter which energy supplier you pay; your supplier doesn't fix network faults.

While you wait:

• Switch off appliances that could start up unexpectedly when power returns, such as ovens, heaters and irons
• Leave one light switched on so you know when power is back
• Keep fridge and freezer doors closed
• Use torches rather than candles where possible
• Check on vulnerable neighbours, and register for your network operator's Priority Services Register if someone in your home relies on medical equipment

Only your property is affected

If neighbours have power and you don't, go to your consumer unit. Look for a main switch, RCD or circuit breaker that is in the off or down position.

1. If a single circuit breaker has tripped, switch it back on. If it holds, the trip may have been caused by a one-off overload, for example a kettle and heater on at the same time.
2. If an RCD has tripped, see the section below on finding the cause.
3. If nothing has tripped and you have no power at all, check whether you have a prepayment meter that has run out of credit. If not, the fault may be on the supply side of your meter, such as the main fuse. Call 105, as the cut-out and service fuse belong to the network operator and must not be touched.

RCD keeps tripping: how to find the cause

An RCD (residual current device) switches off when it detects current leaking to earth. It is doing its job, so never tape it up or bypass it. Instead, try this:

1. Unplug every appliance on the affected circuits. Don't just switch them off at the wall; remove the plugs.
2. Reset the RCD.
3. If it holds, plug appliances back in one at a time, waiting a moment between each. When the RCD trips again, the last item you connected is likely to be faulty. Common culprits are kettles, washing machines, dishwashers, immersion heaters and outdoor equipment.
4. If it trips with everything unplugged, switch off all the circuit breakers below the RCD, reset the RCD, then switch the breakers back on one at a time. The breaker that causes the trip points to the faulty circuit.

If the RCD trips with no appliances plugged in, or the fault is on a fixed circuit such as lighting, an oven or an outside light, the problem is in the wiring and you need an electrician. Common causes include water getting into outdoor fittings, nails or screws through cables, rodent damage and deteriorating insulation in older homes.

Frequent nuisance tripping can also be a design issue. Older dual RCD boards put many circuits on one device, so small leakages from lots of appliances add up. Upgrading to an RCBO board, where each circuit has its own protection, often solves this. Our guide to consumer unit replacement costs explains the options.

When to call an emergency electrician

Call an electrician straight away if:

• There is a burning smell, scorch marks or melted plastic on sockets, switches or the consumer unit
• A trip switch won't reset, or trips immediately with everything unplugged
• You've lost power to essential circuits such as heating, fridge or medical equipment and the fault is inside your property
• Water has got into lights, sockets or the consumer unit
• Cables have been damaged during DIY or building work
• You get a tingle or shock from a switch, appliance, tap or metal pipe

If you aren't sure, it is always better to switch off and ask. Our 24/7 emergency electricians cover all of London and the Home Counties, with no call-out charge.

What not to do

• Don't keep resetting a breaker or RCD that trips straight away; it is telling you something is wrong
• Don't open up the consumer unit, meter or the sealed cut-out
• Don't use an appliance you suspect is faulty "just to check"
• Don't attempt repairs to fixed wiring yourself; in homes, many electrical jobs are notifiable under Part P and must be carried out by a competent person

Landlords and businesses

For landlords, an electrical fault that leaves tenants without power or heating needs a prompt response, and any repair should be properly certified. If repeated faults are appearing, it may be time for a fresh EICR to identify underlying problems before they become emergencies. Businesses have duties under the Electricity at Work Regulations 1989 to maintain installations to prevent danger, and regular inspection through a commercial EICR is the usual way to show this.

Need help now?

Polarity Electrics' NICEIC-certified engineers are available 24 hours a day, every day of the year. We'll talk you through making things safe over the phone, then get an engineer to you as quickly as possible. Call 0203 908 4790 now, or for non-urgent repairs book online.