Choosing a Consumer Unit / Fuse Box
Updated: Nov 14, 2022
The Heart of Your Electrical Installation
The consumer unit is the most important and critical part part of your elctrical installation.
It contains the devices that cut the electricity off when something goes wrong to save lives.
It's probably also the most likely part of your fixed electrical installation to cause a fire.
It's important to choose a unit that maximizes the protection for you and your family whilst minimising the inconvenience when an electrical fault in your house causes a circuit to trip.
Modern consumer units contain RCD's (Residual current devices), they are intended to trip very quickly when there are very small fault currents. The intention is that the current required to trip them is significantly less than the current required to cause serious injury or death to someone. There is still a chance that someone could still die from electric shock but it is significantly reduced by RCD's.
The sensitivity of RCD's causes challenges because they can trip with simple things like a bulb failing and if your RCD is protecting multiple circuits a bulb failure can result is loosing power to many devices including fridges and freezers.
Consumer units have many electrical connections in them, some like connection to the electricity meter, shower and cooker carry quite large currents. If the connections become slightly loose the circuits will still work but the lose connection will have increased resistance. The increased resistance causes the connection to heat up, eventually to the point of melting the device and causing a fire.
In the past RCD's were expensive, this lead to consumer units being designed with just one or two RCD's protecting all the circuits, meaning that one fault would disconnect half or all of your circuits. Today we can look at solutions using RCBO's which combine the RCD and circuit breaker function in to a single device, at the time of writing type A RCBO's add between about £10 and £40 per circuit to the cost of a con
sumer unit depending on brand and specific requirements.
At Newcroft electrics we believe all or at least some circuits should be protected by independent RCBO's to improve reliability, for example putting the kitchen on an RCBO would prevent a fault on another circuit switching the fridge and freezer off. It's probably also a good idea to protect the cooker and heating circuits so that a single fault does not become a major problem requiring an expensive emergency call out.
We also believe in fitting quality equipment, especially with consumer units as faults in the worst case can cause fires.
Hager could be considered as the BMW of the consumer unit world, offering extremely high quality good looking consumer units and if you have the budget are highly recommended.