Rexel responds to 18th Edition Wiring Regulations DPC

With the draft for the 18th edition of the IET Wiring Regulations recently released for public comment, Mark McCall, Category Manager at Rexel UK, outlines what he believes to be the top five proposed changes set to affect electrical contractors, which, if implemented will come into effect from 1st January 2019.

The changes outlined in the 18th edition aim to unify with CENELEC and IEC 60364 standards, incorporate new technology and methodology, and provide further clarification on existing regulations.

Until 23rd August 2017, the IET is sharing the proposed changes with members of the IET and inviting their feedback through the draft for public comment (DPC). Whilst at this stage the amendments are very much proposed and subject to change, or even cancellation, it is important that electrical contractors now begin to familiarise themselves with the impact any potential changes may have on their businesses.

Surge protection

Playing a vital role in protecting sensitive electrical equipment from damage caused by overvoltages, surge protection is a key consideration for electrical contractors. As part of the anticipated changes Section 443 has been redrafted and now proposes surge protection must be provided where consequence affects human life, public services, cultural heritage and commercial or industrial activity, clarifying existing regulations in relation to the reference of risk of lighting in relation to thunderstorms. This tightening of regulations means that it will no longer be sufficient for contractors to simply provide a risk assessment in these cases and protection against transient overvoltage must be provided.

Energy Efficiency

Energy efficiency has been considered for the first time as part of the new regulations. Part 8, which is an entirely new section, provides requirements, measures and recommendations for the design and erection of types of electrical installation for optimising efficiency.

The new requirements apply to both new and existing installations. In addition, Part 8 also covers the point system that installers can give to energy measures, providing them with overall efficiency class between EIEC 0 (very low) and EIEC 4 (optimised efficiency installation). In short, this will mean that contractors are able to meet demands of their clients, which are increasingly focused on having energy efficient electrical installations.

Electric vehicle charging

Changes have also been proposed to section 722, stipulating that each EV charging point must be protected by its own RCD of at least type A, unless the circuit uses the protective measure of electrical separation. Significant changes have also been made to the allowances of the use of the PME earthing facility and the requirements for socket-outlets and connectors. These changes, if accepted, will reduce a potential system fault developing between the conductive parts connected to the PME earth terminal and the general mass of Earth, significantly increasing the safety of these devices.

Precautions against fire

Another of the new additions to the 18th edition comes from Regulations 421.7, concerning the installation of arc fault detection devices in order to mitigate the risk of a fire in final circuits of a fixed installation due to arc fault currents. Regulation 422.21 has also been redrafted to take into account the requirements of the European Constructions Regulations as to when AFDD’s should be used. Should this regulation go ahead, contractors must start to further familiarise themselves with AFDD’s and their usage.

Floor heating systems

A complete revision, has seen Section 753 extended to potentially apply to embedded electric heating systems for surface heating and covers both indoor and outdoor systems, this includes, but is not limited to, heating systems for walls, ceilings, floors, roofs, drainpipes, gutters, pipes, stairs, roadways and non-hardened compacted areas.

Throughout the DPC, and into the finalisation of the 18th edition of the IET Wiring Regulations, Rexel’s team of experts will be on hand to provide electrical contractors with industry insight and compliant products to help them to navigate through the transition to the IET 18th Edition Wiring Regulations seamlessly.

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