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Low Voltage

Find an array of resources related to low voltage including editable certificates, risk assessments, guidance notes and technical bulletins. All provided to help your business grow and build business resilience. 

Low voltage predominately covers design and installation activities associated with:

  • BS 7671 – Requirements for Electrical Installations
  • BS 7909 - Code of practice for temporary electrical systems for entertainment and related purposes
  • BS 5266 - Code of practice for the emergency escape lighting of premises

Have a specific question? 

Contact the Technical team directly via phone or email and a qualified expert will be in touch!

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ECA Resources:


Guidance notes produced by ECA's qualified technical experts offer concise advice on specific areas of interest in Low Voltage.                                                                                                 

BS 7671:2018+A2:2022 
BS 7671:2018 Amendment 3 Draft for Public Comment (DPC)
Requirements for Cable Separation
Installing LV supplies from HV transformers to consumer installations
Corrigendum to BS 7671:2018+A2:2022 
Changes to Section 710 in BS 7671 Amendment 2
A Brief Guide to Installations in Medical Locations
When is TN-C-S PME or PNB?
Self-Calibration of Test Instruments
Top 10 Changes in Amendment 2
Precautions where particular risks of fire exist
Changes to Electrical Testing (and Paperwork)
Different Types of RCDs (and other considerations)
BS 7671:2018 
A guide to work on or near live LV electrical systems
Safe Isolation 
Single and solid point bonding of single-core cables
BIM - the transition from PAS 1192 to BS EN ISO 19650
ERA 69-30 series of guides
Arc Flash Risk Assessments in the UK
IET CoP In-service Inspection & Testing of Electrical Equipment – 5th Edition

Electrotechnical Assessment Specification 

EICR coding consideration 
Adequacy of Existing DNO Fused Cut-Outs
Use of non typical socket outlets
Raised Access Floor Systems - Earthing & Bonding
TT Earthing Systems - Guidance Note 
Using Armouring as a Protective Conductor
Fault Currents in Generator Fed Installations
Guidance Note - Documentation Identification Notices v1.2
Transient over-voltage protection
The Employer’s Legal Duties to maintain Safe Electrical Installations

Cross-sectional Area of Neutral Conductors

Best practice advice based on one of the most frequent technical enquiries.

Does Metallic Cable Tray / Ladder Require Bonding?
Guide to Electrical Maintenance

Technical Bulletins are designed to offer good advice on specific technical questions received through our technical  helpline or via our network of branch and regional meetings.                                

BS 7671:2018+A2:2022
Reporting of Possible Neutral Current Diversion
Installing Surge Protective Devices retrospectively
Additional requirements for outside lighting
Verbal forms for expression of provisions
Table 3A has been removed from BS 7671:2018+A2:2022
Clarifications made to the requirements for RCD testing
Protection Against Overvoltage
Precautions where particular risks of fire exist
Installing and additional earth electrode in TN earthing systems
Bonding of Outbuildings
Date of Inception for BS 7671:2018+A2:2022
The use of BS 7288-type socket-RCDs and Regulations 531.3.4.1 and 531.3.4.2
Arc Fault Detection Devices (AFDDs)
HMO, care homes and purpose-built student accommodation definition
Functional Earthing
Installing an additional earth electrode in TN earthing system
BS 7671:2018 
Bonding of commercial kitchens
Correct selection of telecommunications cabling
Installing domestic AC voltage optimisers
Continuing professional development and requirements for ECA Members
Naming conventions for electrical installations 
Increased awareness of manufacture instructions and recommendations
Use of consumers electrical cabinet for additional equipment
Halogen and fluorescent lamp sale ban
Domestic consumer units not supplied by BS 88-3 fuses
EICR observation writing
Electrical Safety in the private rented sector
BIM
BS 7671: 2018 Amendment 1
LED lights and circuit breaker selection
Technical Bulletin - Working in the Republic of Ireland
AFDD and Sleeping Accomodation
Explanation of definitions related to sleeping accommodation.
Responsibilities for Passive Fire Stopping of Building Services Structural Openings
This bulletin reminds members of the vital importance of establishing contractual responsibilities for passive fire stopping around building services installations.
Use of YY CY SY Cables
Supplementary equipotential bonding
Voltage Drop

Voltage drop in electrical designs and the requirements within BS 7671      

IP Rating of Trunking

The trunking currently being used in electrical installations typically has an International Protection (IP) rating (otherwise known as Ingress Protection Rating) of IP3X where joints have been fabricated on site.

Departures from BS 7671
Cable Supports
RCDs and Socket Outlets
Selectivity & Desk Studies

Wiring Accessory Replacement

This technical bulletin addresses the questions about wiring accessory replacement and provides best practice guidance which can be applied to both commercial and domestic locations.​

Joining Dissimilar Metals

This technical bulletin is designed to offer advice and guidance when working on and with electrical equipment of dissimilar metals that are to be connected, or joined together.

Electrical Installations After a Flood or Fire

Floods and fires of any magnitude can have detrimental effects on any electrical nstallation. This bulletin provides property professionals with clear advice on recognising these potential dangers.      

Access authoritative Application Guides compiled and published by our technical experts, addressing best practice engineering in low voltage.                                                                            

The Employer’s Legal Duties to maintain Safe Electrical Installations

Electricity is a hugely versatile and convenient source of energy, but it can be dangerous if the electrical system has not been properly designed, installed, operated and maintained. This guide aims to help employers (building and other premises owners, landlords or managing agents) understand their legal duties to ensure adequate inspection, testing and maintenance of electrical systems.

New Generation of Electrical Installations Remote Powering: “Power Over Ethernet”

Reducing global consumption, improving energy efficiency, exploring the universe of data, managing devices are a necessity for all types of buildings or infrastructure. The transition from traditional installations to Power over Ethernet has started in all European countries. With PoE, installers can better meet their clients’ need and demand for efficient, connected and “next generation” buildings. European electrical contractors must adapt NOW. This technical reference guide is a common standard for all European electrical installers and may also be useful for designers, architects and controllers.

Cables and CPR

New European regulations take effect from 1st July 2017, regarding the testing and classification of cables by manufacturers, concerning  how they behave during fire conditions.

This guide has been updated in accordance of BS 7671:2018.

This will bring in a requirement that the majority of cables for permanent installation within a building will have to be suitably  classified, and selected to be the appropriate category by designers, specifiers and installers alike.

This ECA Application Guide has been prepared detailing all that is needed to be known, giving practical guidance on the subject for designers and installers.

Electrical Heating Design

The following application guide is designed to give readers additional information about electric heating systems in relation to the design and build of different projects. This guide is intended to offer practical guidance to all, although due to the nature of the subject must make reference to other guidance documents and standards.

Download 'Heating Loss Calculation' table >

Regulations and Requirements for Inspection and Testing

This application guide is intended to offer advice on the legal requirements for common electrical systems that contractors work upon. Due to the huge variety of electrical systems, this guide is following on six specific standards.

Selection of LV Switchgear and Protective Devices

This application guidance is intended to provide readers with information regarding the design, selection and installation of LV switchgear and protective devices and to offer practical guidance to all, though due to the nature of the subject must make reference to other guidance documents and standards.

Application Guidance on Arc Flash Risk Assessment and Arc Flash Protection

Arc Flash Risk Assessment and Arc Flash Protection, are topics of North-American (USA) origin and concern the assessment and mitigation of Arc Flash Hazard(s) to personnel working on, or in reasonably close proximity to, energised electrical plant and equipment. The topic is very much coming to the fore in the UK via manufacturers and suppliers of PPE (Personal Protective Equipment) and their efforts are focussed on...

ECA offers a variety of Member-only editable certificates and risk assessments to support Members with their certification requirements and day-to-day work. Please utilise the latest version of Adobe Acrobat Reader to ensure that certificate functionality is optimised - click on 'How to edit the ECA branded certificates' for more information.                                                                                                                                                                                                                                                                            

All the ECA technical editable certificates are provided in a pdf file format. 

In order to save your changes to the editable certificate, please make sure you download each certificate to your device, before making the edits. If you do not download the certificate and make changes on the web browser or via online pdf viewer (i.e. Google Chrome), your changes may be lost once you reopen the certificate.

View our guidance on how to save your technical documents in a non-editable PDF format once completed > ​

ECA recommends using the latest version of Adobe Acrobat Reader software to view and edit all certificates. Adobe Reader is free software and can be downloaded from Adobe website, iTunes or Google Play.

Please also note that 'Adobe Fill and Sign' software has a limit of 200 fields to a page, and may therefore not be suitable for use with certain certificates.

Some ECA certificates allow adding your business logo to the form. Please note, due to pdf file restrictions, the logo uploaded must be in a pdf file format. 

If you should experience any problems with the ECA editable certificates, please contact Member Services on 020 7313 4800 (option 1).

We need your help! 

ECA Technical Manager Darren Crannis asks ECA Members to share their experiences with Low Voltage supplies to buildings. We are working with industry partners to standardise the information provided across Distribution Network Operators, or DNOs. Watch the video to find out more...



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