Burnt or faulty fuse board: emergency fuse box repair in Seville, Spain

Signs that your fuse board is faulty

The fuse board is the heart of your installation: it receives the line coming up from the meter and splits it into circuits, each with its own protection. Spaniards call it the cuadro eléctrico; most British residents just say “fuse box”, even though modern ones have no fuses. When it fails, it usually warns you with one of these symptoms:

• A smell of burning or melted plastic when you open the cover.
• Blackened terminals or cables with deformed insulation at the connections.
• A circuit breaker or the RCD that will not reset, even with the appliances unplugged.
• Buzzing, crackling or clicking inside the board.
• The cover or a breaker feels hot to the touch.
• The whole home without power although the main switch is up.

If there is also smoke, switch off the main switch if you can do so safely and read burning smell.

What is not a fuse board fault

Before assuming the worst, check what has actually dropped. If a single breaker trips on its own, it is an overload or short circuit on that circuit: see MCB keeps tripping. If the lever with the TEST button drops, it is an earth leakage: see RCD keeps tripping. And if nothing in the board moves but the whole home goes dark for a few seconds, it is the smart meter cutting you off for exceeding your contracted power, explained in power limiter tripping. This page is for when the board itself is damaged.

Most common causes

• Loose terminals. Temperature changes loosen the screws, contact gets worse and the connection heats up. It is the number one cause of burnt fuse boards.
• Protections working at their limit. Breakers or a main switch that carry, day after day, loads they were never sized for, typical after adding air conditioning or an induction hob (cooktop).
• Ageing components. Breakers and RCDs with many years of service lose precision or stop resetting.
• Surges. A storm or a network fault can damage RCDs, surge protectors and electronic components. We cover it in storm damage.
• Damp. Fuse boards in garages, storerooms or patios where water gets in or condensation builds up.

How we repair the fuse board

1. We cut the supply and confirm there is no voltage before working.
2. We inspect every connection: main switch, RCDs, circuit breakers, busbars and incoming and outgoing cables.
3. We replace what is damaged: burnt terminals, faulty breakers, damaged lengths of internal cable.
4. We retighten every connection, not just the one that failed, because if one has worked loose there are probably others.
5. We test the RCDs and breakers and check that each protection matches the cross-section of its cable.
6. If the board justifies it, we inspect it with a thermal imaging camera to spot hot points that cannot be seen yet.

The fuse board of a home is governed by ITC-BT-17 of the Spanish Low Voltage Electrotechnical Regulation (REBT), which sets out the main control and protection devices.

Repair or replace?

Repairing makes sense when the board is fairly recent and the fault is isolated. Replacing it is the sensible choice when:

• It has no RCD, or only one for the whole home.
• Its breakers are very old or no compatible spares exist.
• It has overheated generally and several components are affected.
• You want to add circuits for air conditioning, an induction hob or an EV charger.

A new fuse board includes a main switch, RCDs shared out by area, a breaker per circuit and, if you need it, a surge protector. We explain it in detail on fuse board replacement, and the protection upgrades on electrical safety.

Burnt fuse boards in Seville homes

In the 1960s and 1970s flats of Nervión, Los Remedios or Heliópolis, many fuse boards have been extended bit by bit: one breaker added for the air conditioning, another for the water heater (termo), cables joined inside the box. With 40 degrees in summer and the air conditioning running all afternoon, the terminals of the main switch heat up day after day until they turn black. It is a fault we see often at the end of summer. In Parque Alcosa homes or the villas of the Aljarafe, the weak point is usually different: fuse boards in garages or porches where damp corrodes the busbar.

Guide prices

You get the fixed price before we start. If the fuse board has left you without power, also read power cut at home and call our 24-hour emergency electrician service. Other faults are on the emergency electrician page.