We all know that things in the electrical industry never stand still, and that includes the regulations. The most recent, Amendment 3 of BS 7671 Requirements for Electrical Installations, was published in July 2024.
If you're working as an electrician, staying up to date with the latest changes in the 18th Edition of Wiring Regulation isn’t just good practice – it's essential for safety, compliance, and winning work for your business.
So, what's changed in the latest Amendment 3, and how can you make sure you’re up to speed?
Here’s what you need to know, straight from the team at BED Electrical.
What Is The 18th Edition?
The 18th Edition of the IET Wiring Regulation sets the standards for electrical installations in the UK. It’s the rulebook for ensuring work is done safely, efficiently and to a legally compliant standard.
Amendments are released to reflect new technologies, improve safety, or respond to industry developments. And the latest update is no exception.
Key Updates in Amendment 3:2024
Amendment 3 BS 7671 addresses a key issue regarding the selection and installation of protective devices, particularly where installed with an additional source of power, such as battery storage, or solar PV. It also introduces a new regulation (530.3.201) for the use of bidirectional and unidirectional devices, and two new definitions.
Unidirectional vs Bidirectional Devices
A new UK specific clause clarifies that when installing protective devices (RCDs, RCBOs, circuit-brakers, AFDDs), contractors must now explicitly consider whether a unidirectional or bidirectional device is needed, based on power flow direction.
Definitions Added
Bidirectional protective device: Can accept power flow in either direction.
Unidirectional protective device: Designed for power in only one direction.
Product Marking Requirements:
Affected devices (RCDs, RCBOs, circuit-brakers, AFDDs) must now have clear labelling (e.g.: “In/Out”, “Line/Load”, or directional arrows) to avoid misconnection.
Renewable Energy & Battery Systems:
These changes respond to installers increasingly working on renewable-energy circuits (like solar PV, battery storage, EV-to-grid), where power may flow in both directions, warranting correct protective device selection.
What The Changes Mean for Contractors and Businesses.
Installation Design Must Adapt:
You must consider power-flow direction when specifying protective devices, especially in systems with renewables or battery storage.
Product Selection Checks:
Orders should specify whether you need uni- or bi- directional devices and make sure they are properly marked.
Inspection and Testing Guidance:
EICRs and periodic checks will now include verifying that devices are correctly marked and installed per the new regulation.
Retrofits may be needed:
Existing installations with PV or batteries might require updating protective devices to comply during inspections.
How BED Can Help You Stay Compliant.
BED Stocks Compliant Products.
BED Electrical stocks a wide range of compliant products, including AFDDs, SPDs, and RCD units, to help you meet the latest regulatory requirements. Our team can help you select the correct item for your installation.
Expert Technical Guidance
Our trade counter experts and area sales managers stay up to date with BS 7671 updates and can advise on device selection, installation best practices, and marking requirements.
Training Opportunities:
BED Electrical is proud to offer multiple training courses throughout the year, offering upskilling sessions for contractors who want to keep their knowledge and work compliant.
Ask us in your local branch about any upcoming training course dates.
Your Next Steps:
- Download the free Amendment 3 PDF from the IET/BSI websites and store it with your 18th Edition Brown Book.
- Make sure your teams are aware of the regulations and are selecting the right protective devices.
- Visit any of our 6 branches in the East Midlands or contact your local area manager for support, training and product advice.
IET Website: https://electrical.theiet.org/bs-7671/updates-to-18th-edition/
In summary, Amendment 3 brings important clarity around protective device usage in the renewable energy field. With BED Electricals’ stocked solutions and expert guidance, you can stay compliant, confident and ready for any installation challenge.
Staying on top of regulation changes isn’t just about ticking a box. It's about staying competitive, staying legal, and most importantly, staying safe.
BED Electrical is here to help you navigate these updates with confidence.
Sign up for a trade account with BED today!