Knowing a bit about your new home’s electrics will help to keep you and your family safe, and minimise inconvenience if things go wrong.
What is the consumer unit?
Commonly referred to as a fuse box, this is where the electricity for your entire home is controlled. The position of consumer units and electric meters differs between different types of houses and apartments. You should have been shown the location of these for your own home during the handover.
Your consumer unit and electricity meter will often be found near the front door of your house, often in the hallway cupboard. In an apartment, the electricity meter may be in a service cupboard outside your door, but your consumer unit will be inside your home, normally near the front door.
Under the hinged front cover there’s a row of switches, each controlling a different aspect of the electricity in your home. Each switch will be labelled to show which area of the home it controls. These are known as miniature circuit breakers, or MCBs. You can use them to cut power to a particular appliance or part of your home. It’s good practice to turn off power to your lighting circuit when changing a bulb.
The large ‘main switch’ on the far right can be used to completely isolate the electricity to your home. You may notice the row of switches is split into two groups, each ending with a slightly different looking switch and a small button. These are RCDs, devices that immediately cut off the electricity supply if a person comes into contact with a live electrical connection. Knowing what these different switches are for will help you to know what to do in the event of an electrical fault.
Dealing with electrical faults
Losing the electrical supply to your home can be frustrating and even alarming if you’re suddenly left in the dark. Normally, though, it’s nothing serious. Follow our step-by-step guide to know what to do in this situation.
Finding the fault
If you lose electricity in your home, the first thing to do is check your consumer unit to see if any of the switches are in the ‘off’ position.
- If the main switch and RCDs are all switched on, the most likely cause is a power cut. Check whether your neighbours have power and, if necessary, call your local supplier for more information.
- If some switches are off, start by turning on the main switch (on the far right). Then turn on any RCDs that have flipped to the off position.
- You may find that one of the RCD switches immediately flips back to the off position. This indicates a fault in one of the circuits controlled by the switches to the left of that RCD. If this happens, switch off all of the labelled switches (MCBs) to the left of the RCD that continues to switch itself off (or ‘trip’).
- Now switch on the RCD in question and, one at a time, turn on the MCB switches until the RCD trips again, or until you encounter a switch that flips itself off as soon as you turn it on. You now know which circuit is causing the problem.
- You can now re-enable all of the switches in your consumer unit, apart from the one you have identified to be at fault.
Finding the cause
Now that you’ve found the fault you can investigate what’s behind it. If it’s a lighting circuit causing the problem, or a circuit for any built-in appliance such as a hob or electric shower, you will need the help of an electrician.
If the switch controls a room circuit (ie one that supplies power to wall sockets), you can take the same approach again to finding the cause of the problem. Unplug all electrical equipment from the room or rooms controlled by that circuit breaker, then switch it back on and plug your equipment back in as it was before, one device at a time, until the power trips again. You now know which device is causing your circuit breakers to trip.