Electrical
Why your fuse board keeps tripping
A trip is not the fault. It is the fault being caught. What the different switches are telling you, and how far to go before you stop resetting.
Written by the ARA Services engineering team · Updated August 2026
The short answer
A breaker for one circuit tripping means an overload or a short on that circuit. The wider switch that takes out half the house is an RCD, and it trips because current is leaking to earth. Unplug everything on the affected circuit, reset, then add appliances back one at a time. If it trips with nothing plugged in, trips instantly every time, or trips with all the breakers off, stop resetting and get it tested.
First, see which switch moved
The board tells you a lot before you touch anything. Look at what is down and what is still on.
A single small breaker (MCB)
Protects one circuit against too much current — an overload or a short. If it is the kitchen, something on that ring has failed or you are asking too much of it.
The wide switch (RCD)
Watches for current leaking to earth across a bank of circuits and cuts in milliseconds. This is the one that takes out lights and sockets together in older boards.
One breaker with a test button (RCBO)
Does both jobs for a single circuit. Modern boards use these, which is why a fault takes out one room rather than the whole floor.
The main switch
If the board is dead with the main switch up, the problem is upstream of you — the supply, the meter or the tails. That is not a reset job.
Not sure what you are looking at? Describe the board on the phone and we will talk you through it.
077 2715 4746The appliance test
Most repeated tripping comes from one item, and finding it is methodical rather than clever. Unplug everything on the affected circuit, reset the switch, then plug items back in one at a time and use each one properly — a washing machine heater or a kettle element often only leaks once it heats up.
Kettles, toasters, washing machines, dishwashers and immersion heaters are the usual culprits, in that order.
Anything outdoors — garden lighting, an outbuilding socket, an EV charger — is the first suspect if trips follow wet weather.
Extension leads and phone chargers fail more often than people expect, and so do damaged appliance flexes.
If it trips the moment you switch a specific socket or light on, tell us which one. That halves the fault finding.
Found the appliance but it is the only one you own? We test the circuit rather than replace the kettle.
Electrical fault findingWhen nothing is plugged in and it still trips
Then the leakage is in the fixed wiring or in the board itself, and this is where DIY stops. Water in an outdoor circuit, a nail or screw through a cable from a previous job, cable overheated by recessed spotlights, rodent damage in a loft, and perished rubber insulation in properties last wired in the sixties all produce exactly this symptom.
There is also a quieter cause: every appliance leaks a tiny amount to earth in normal use, and on an older split-load board where one device protects half the house, that standing leakage adds up until the board sits on the edge of tripping. Splitting the circuits onto individual RCBOs cures it properly.
Nuisance tripping on an old split-load board is usually solved by the board, not the appliances.
Fuse board upgradesWhen to stop resetting
An RCD is a safety device doing its job. Repeatedly forcing it back on leaves a live fault in the wall.
Any burning smell, scorch marks, buzzing or warmth at the board or at a socket — stop and call immediately.
It trips again within seconds, every time, with nothing plugged in.
It trips with every breaker switched off, which points at the device or the tails feeding it.
It trips whenever it rains, which means water is getting into a circuit that will not dry out on its own.
Smell of burning or a hot socket? Leave the circuit off and call us now.
Call 077 2715 4746What the visit involves
The electrician isolates and tests each circuit — insulation resistance, earth loop impedance, RCD trip times — to find where the leakage is rather than guessing at it. You get the fault, the fix and the price before work starts, and the repair is certified. Where the board itself is the problem, we set out what an upgrade involves and what it costs.
NICEIC approved electricians across every London borough, with the work certified on completion.
Book an electricianElectrical questions
Is it safe to leave the circuit switched off?
Yes, and it is safer than repeatedly resetting it. Leave the breaker for that circuit off, use other circuits normally, and get it tested.
Can an RCD be added to an old fuse box?
Sometimes, but on a board old enough to have no RCD at all, replacing the consumer unit is usually the better answer and brings the installation up to current regulations.
Why does it only trip in the morning?
Because that is when the immersion, the shower or the washing machine runs. Trips that follow a routine are usually an appliance element breaking down as it heats.
Do I need an EICR after a fault like this?
Not automatically, but repeated tripping in an older installation is a good reason to have one. Landlords need a satisfactory report in any case.
Book an electrician
Tell us the postcode and which switch is tripping. We test the circuit, fix the fault and certify the work.