Consumer Unit Regulation Changes

What's Changing?

You may or may not be aware but as of the 1st January 2019 there is a new regulation surrounding Consumer Units under regulation BS7671:2018. Many brands have already got a head start on the new regulations in preparation.  Within this blog we are focussing on the changes that specifically affect circuit protection products.

One of the major changes between the 17th and 18th editions is the change to RCD protection.  The regulation states that additional protection by use of a 30mA RCD is now required for all lighting circuits in domestic household premises – with no exceptions listed.

For socket outlets with ratings up to and including 32A, a 30mA RCD is also now required - this is a change from the previous regulation which only applied to sockets up to 20A rating.

Another new addition to the regulations is the recommendation for Arc Fault Detection Devices (AFDD) to protect against fire caused by arc faults in AC circuits. Arcing is incredibly dangerous because it creates high intensity heating at the point of the arc, resulting in burning particles that may ignite surrounding materials.

Unlike RCDs and MCBs, these AFDDs work by protecting specifically against arc faults as they will automatically trip a circuit when they detect dangerous electric arcs. Locations in which AFDDs are particularly important would be hotels or apartments, wooden buildings or fire propagating buildings such as high rise towers.  AFDDs are fairly new to the domestic market, but we predict a big increase in interest for these over the coming months.

Within the 17th Edition of the Wiring Regulations, the requirements of surge protection were determined through risk assessment methods. Now, overvoltage protection is required in certain circumstances. For example, where there is risk of serious injury or of loss of life, where many co-located people are affected, where there is an interruption to public services, or commercial / industrial activity.  For circumstances where overvoltage protection is not required, a risk assessment can be carried out. If a risk assessment is not carried out, overvoltage protection must be provided.

While we’ve given guidance here, we always recommend that all installers obtain their own copy of BS7671:2018 and follow the requirements and recommendations in the 18th Edition of the IET Wiring Regulations.