Circuit Problem

Fuse Board Keeps Tripping?

There's a fault somewhere on your circuit. We can find it and fix it - usually the same day.

Same-Day Callouts
CHAS Approved
Expert Diagnosis

Understanding Your Fuse Board

Your consumer unit contains two types of protection. MCBs (the narrow switches) protect individual circuits from overloads and short circuits – they trip when too much current flows through the cable. RCDs (the wider switches) detect earth faults – they trip when current leaks to earth, which could mean someone is getting a shock or insulation has broken down somewhere on the circuit.

When we attend a tripping callout, the first thing we do is identify which device has tripped and test it systematically. For RCD trips, we disconnect circuits one at a time and reset – the one that causes the trip is the faulty circuit. We then perform insulation resistance testing on that circuit to pinpoint the fault, whether it's degraded cabling, a waterlogged junction box, or a failing appliance. Most tripping faults are resolved within 1–2 hours.

MCB Tripped (one switch down)

Usually indicates an overload or short circuit on that specific circuit. Only that circuit loses power.

RCD Tripped (larger switch)

Indicates an earth fault. Multiple circuits may lose power as one RCD typically protects several circuits.

Common Causes of Tripping

Here's what might be causing your fuse board to trip repeatedly.

Overloaded Circuit

Too many appliances drawing power from one circuit, exceeding the MCB's rated capacity.

Try: Reduce the load by unplugging some appliances, especially high-power ones like heaters.

Short Circuit

Live and neutral wires touching, causing a surge of current that trips the MCB instantly.

Try: This needs professional investigation - there may be damaged wiring.

Faulty Appliance

An appliance with an internal fault drawing excessive current or causing a short.

Try: Unplug appliances one by one to identify the faulty item.

Water Damage

Moisture entering sockets or junction boxes causing short circuits or earth faults.

Try: Check for signs of water ingress, especially after heavy rain or leaks.

Worn MCB

The circuit breaker itself may be old and tripping at lower currents than designed.

Try: An electrician can test the MCB and replace if faulty.

When to Call an Electrician

Call Us If:

  • The board trips immediately when reset
  • You can't identify which appliance is causing it
  • There's a burning smell or visible damage
  • It trips with nothing plugged in
  • Your fuse board looks old or has rewirable fuses

What We'll Do:

  • Test each circuit systematically
  • Use specialist equipment to locate faults
  • Explain what's wrong in plain English
  • Provide a clear quote before any work
  • Fix the problem and certify the work

Frequently Asked Questions

Need Help With Your Fuse Board?

Same-day callouts available across Devon. We'll find the fault and fix it properly.