Are split-load fuse boards compliant ?

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Many homes and businesses in Bristol has a split-load fuse board already installed, but do they still comply ?

A split-load fuse board is typically made up of 1 main switch, an RCD protecting several circuits followed by another RCD protecting several more circuits.You can still find split-load consumer units (fuse boards) available to purchase in DIY stores.A repituble electrician will now only install RCBO consumer units as standard these days.

Why an RCBO fuse board and what are they?

RCBO fuse boards are made up of a main switch and each individual circuit is protected by its own RCBO , RCBOs are similar to an RCD but also incorporating a MCB.

As a professional electrician when we carry out an installation , rewire or a fuse board upgrade , we want to minimise the potential for unwanted tripping.

What is unwanted tripping and what causes it ?

Modern electrical equipment leaks a small amount of current to earth, such as induction hobs, fridges, dishwashers and computers, each appliance could leak 5mA or even more.

If multiple circuits share 1 x 30mA RCD (found on a split-load fuse board) all these earth leakages can add up and go over the 30% allowance of fault current for the RCD, so for instance if we have 2 circuits protected by 1 x RCD the combined earth leakage from the appliances could potentially have over 10mA of leakage which could cause nuisance tripping / unwanted tripping. If you find your RCD trips at random times and every now and again, that could mean there is not a fault with the wiring , but an earth leakage issue.

So what can we do to minimise unwanted tripping ?

We install RCBOs for each individual circuit.By installing an RCBO fuse board we are minimising unwanted tripping, new circuits can be easily added to the fuse board with out the need of installing additional fuse boards (if there is enough spare ways that is) and we are potentially future proofing the installation.

So can we still install split load fuse boards ?

Some electricians may still install them if they are the high integrity type, and depending on the properties earthing arrangement

They can install an RCD to protect many circuits that has low earth leakage such as lighting and then install RCBOs for high leakage circuits such as socket outlets, cookers, hobs and appliances.

At Burridge Electrical we only install RCBO consumer units with a built in SPD (Surge Protection Device) as standard

We are registered electricians in Bristol and have the relevant insurances and qualifications,all our work is backed by a 6 year NAPIT guarantee.

Call today on 0117 321 6406 for a free, no obligation quotation.