Parts of a Fuse Board

For many Bracknell homeowners, the contents of their fuse board are something of a mystery and here at Thames Valley Electricians we are often asked to explain what each component part is for. We have created this simple guide to the parts of a fuse board to help you gain a clearer understanding of what exactly it is that your fuse board does and why it is so important.

Consumer Unit or Fuse Board? What’s the difference?

When talking about fuse boards you will also come across the term consumer unit and the two terms will often be used interchangeably. So, what is a consumer unit and how is it different to a fuse board? In simple terms a consumer unit is the modern version of a fuse board, and it serves the same purpose. The term fuse board is much more commonly understood and so it has stuck around a consumer unit differs in that it does not have actual fuses, unlike its predecessor. Older style fuse boards were simple devices that featured removable and rewireable fuses that would melt in the event of an electrical fault. They were smaller than a modern consumer unit and far less effective at protecting you and your home. These old-style fuse boards have been phased out since the 1980s, so there are few homes that still have them. If your Bracknell home has this kind of fuse board then it is high time it was upgraded.

Fuse Board Parts

If you take a look at your fuse board, you will see that it is made up of several parts, each with a different purpose. Let’s examine each part in turn:

Main Switch

The main switch is what controls the flow of electricity into your home and will be clearly marked on your fuse board. It is important that you know where to find this switch, as in the event of an emergency, this is what you would use to cut the power.

MCBs

Miniature Circuit Breakers, or MCBs, protect your electrical circuits from damage caused by power surges such as the overloading of sockets (often due to extension cords), or loose wiring. These issues are known as overcurrent events and if undetected can lead to a fire. The MCBs themselves are a small row of switches on your fuse board which toggle on and off. They should be labelled with the individual circuit they protect, such as upstairs lights. If an overcurrent event is detected, the MCB will trip and cut the power to that circuit. Once the issue has been rectified, you simply reset the switch and restore power.

RCDs

An RCD, or Residual Current Device, is a critical safety feature of your fuse board. Your RCD protects you from the dangers of electric shock and is, without a doubt, a lifesaving device. An RCD will switch off the power within milliseconds of detecting an abnormality in the current. This occurs when a live wire is exposed with the most common example being when a wire is accidently cut or damaged during DIY. The RCD will detect the issue immediately, cut the power and save you from a serious shock. If your fuse board does not have an RCD, one should be installed as soon as possible.

RCBO

RCBO stands for Residual Current Breaker with Overcurrent and these can be found in place of MCBs and RCDs on your fuse board. They provide the same high levels of protection as an individual RCD or MCB but combine both functions in one component.

SPD 

A Surge Protection Device (SPD) is the part of your fuse board that protects your electrical equipment against damage caused by a power surge. A power surge is most commonly caused by a lightning strike. As our homes have become filled with more and more electronics, so the amount of damage a power surge could cause has increased - as has the potential bill for the repair and replacement of damaged goods. SPDs are now required for all new installations. If you would like to add SPD protection to your fuse board, Thames Valley Electricians will be happy to advise you.

If you have any further questions about the parts of your fuse board, contact our knowledgeable team at Thames Valley Electricians in Bracknell. Our fully qualified, NICEIC registered electricians will be happy to help with all your fuse board related queries. Contact us today.