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Introduction to the Document Catalogue

The Energy Networks Association (ENA) represents the interests of all energy companies in the UK. The Document Catalogue System is an online catalogue of engineering documents available from the ENA.

Documents available from the site include Technical Specifications, Engineering Recommendations and Reports, BEBS Specifications and reports supporting the electricity network process and policies.

Most documents are available to anybody but a small number are confidential to ENA member companies and can only be accessed by those member companies. The system allows clients that are not full ENA members to purchase documents by credit/debit card via secure transactions provided by WorldPay.

For more information, please click here to be routed to the ENA's corporate website or direct your query to:

Energy Networks Association Limited
4 More London Riverside
London SE1 2AU

Tel:  020 7706 5100
Email:  Lauren Fisher

WARNING! Some of the older (pre 2003) documents available on this site were originally published by the now defunct Electricity Association. Please note that the ENA cannot take responsibility for the condition and content of these older documents and you are advised to seek advice before acting upon information held in them.

40 Documents Published Since Jan 2017

Type     Number     Issue No     Title     Published     Revision Due     Status     Price      
Technical Specifications (TS)41-24Issue 2 (Revision)

Guidelines for the design, installation, testing and maintenance of main earthing systems in substations

Nov 2018Q4 2023Current £Free Add to Order
Engineering Recommendations (EREC)S34Issue 2 (Revision)

A guide for assessing the rise of earth potential at electrical installations

Nov 2018Q4 2023Current £Free Add to Order
Engineering Recommendations (EREC)S34Issue 2 (Revision)

A guide for assessing the rise of earth potential at electrical installations

Nov 2018Q4 2022Current £185.00 Not Available
Engineering Recommendations (EREC)G59/3Issue 3 (Revision)

Recommendations for the connection of Generating Plant to the Distribution Systems of Licensed Distribution Network Operators

Jul 2018Q1 2023Current £Free Add to Order
Engineering Technical Reports (ETR)138Issue 3 (Revision)

Resilience to flooding of Grid and Primary Substations

Jun 2018Q1 2023Current £105.00 Add to Order
Engineering Recommendations (EREC)G98Issue 1 (New)

Requirements for the connection of Fully Type Tested Micro-generators (up to and including 16 A per phase) in parallel with public Low Voltage Distribution Networks on or after 17 May 2019

May 2018Q1 2023Current £Free Add to Order
Engineering Recommendations (EREC)G99Issue 1 (New)

Requirements for the connection of generation equipment in parallel with public distribution networks on or after 17 May 2019

May 2018 Current £Free Add to Order
Technical Specifications (TS)43-93Issue 5 (Revision)Line InsulatorsMar 2018Q1 2023Current £65.00 Add to Order
Engineering Recommendations (EREC)C99Issue 1 (New)Guidance for working on cables under induced voltage conditionsMar 2018Q1 2023Current £100.00 Add to Order
Engineering Recommendations (EREC)G102Issue 1 (New)Pressure rise in enclosed substationsFeb 2018Q1 2023Current £55.00 Add to Order
Engineering Recommendations (EREC)G78Issue 4 (Revision)Recommendations for low voltage supplies to mobile phone base stations with antennae on high voltage structuresFeb 2018Q1 2023Current £100.00 Add to Order
Engineering Recommendations (EREC)S40Issue 1 (New)Prefabricated substationsFeb 2018Q1 2023Current £55.00 Add to Order
Technical Specifications (TS)09-23Issue 2 (Revision)LV link boxesJan 2018Q1 2023Current £45.00 Add to Order
Technical Specifications (TS)12-11Issue 5 (Revision)Enclosed unfilled terminations of cables with rated voltages 12, 24 and 36 kVJan 2018Q1 2023Current £55.00 Add to Order
Engineering Reports (EREP)128Issue 2 (Revision)Risk assessment for communication network operatives working in a ROEP zoneJan 2018Q1 2023Current £65.00 Add to Order
Engineering Reports (EREP)129Issue 2 (Revision)ROEP risk assessment for third parties using equipment connected to Communications Network Provider linesJan 2018Q1 2023Current £105.00 Add to Order
Technical Specifications (TS)43-126Issue 2 (Revision)Fittings for overhead line optical cablesJan 2018Q1 2023Current £Free Not Available
Technical Specifications (TS)43-92Issue 5 (Revision)

Overhead line fittings

Jan 2018Q1 2023Current £65.00 Add to Order
Engineering Recommendations (EREC)M30Issue 2 (Revision)Standard Electricity Network Operator electricity smart meter configurationsJan 2018Q1 2023Current £Free Add to Order
Engineering Recommendations (EREC)S36Issue 2 (Revision)Identification and recording of 'hot' sites - joint procedure for Electricity Industry and Communications Network ProvidersJan 2018Q1 2023Current £30.00 Add to Order
Engineering Technical Reports (ETR)138 - AnnexIssue 1 (New)Resilience to Flooding of Grid and Primary Substations2018 Current £Free Not Available
Engineering Recommendations (EREC)P23Issue 2 (Revision)Guidance on Earth Fault Loop Impedance at Customers’ Intake Supply Terminals (Former title: Consumers’ earth fault protection for compliance with the IEE Wiring Regulations for Electrical Installations)2018Q1 2023Current £45.00 Add to Order
Engineering Recommendations (EREC)P25Issue 2 (Revision)The short-circuit characteristics of single-phase and three-phase low voltage distribution networks2018Q1 2023Current £Free Add to Order
Technical Specifications (TS)PO5Issue 5 (Revision)Protection of telecommunication lines from power lines2018Q1 2023Current £55.00 Add to Order
Engineering Recommendations (EREC)S37Issue 3 (Revision)Code of practice for the safe working on pilot, auxiliary and communication cables2018Q1 2023Current £45.00 Add to Order
Technical Specifications (TS)09-16Issue 3 (Revision)Tests on power cables with XLPE insulation and metallic sheath and their accessories, for rated voltages of 66 kV (Um = 72.5 kV), 110 kV (Um = 123 kV) and 132 kV (Um = 145 kV)Dec 2017Q1 2022Current £45.00 Add to Order
Technical Specifications (TS)43-94Issue 6 (Revision)Earth rods and their connectorsDec 2017Q1 2022Current £55.00 Add to Order
Technical Specifications (TS)50-19Issue 2 (Revision)Standard numbering for small wiring (for switchgear and transformers together with their associated relay panels)Dec 2017Q1 2022Current £45.00 Add to Order
Engineering Recommendations (EREC)G44Issue 3 (Revision)Code of practice for the coordination of power line carrier system frequencies in the range 30.0 kHz to 526.5 kHzDec 2017Q1 2022Current £55.00 Add to Order
Engineering Recommendations (EREC)G80Issue 3 (Revision)Recommendations for the safe working of utilities’ staff and other parties near light rapid transit systemsDec 2017Q1 2022Current £55.00 Add to Order
Engineering Recommendations (EREC)G101Issue 1 (New)Voltage Measurements for Assessment of Compliance with Statutory Voltage LimitsAug 2017Q1 2022Current £Free Add to Order
Engineering Recommendations (EREC)G103Issue 1 (New)Generic industry risk assessment and asset management approach for Low Voltage service termination equipmentAug 2017Q1 2022Current £Free Add to Order
Engineering Technical Reports (ETR)140Issue 1 (New)Statutory Voltage Limits at customers’ terminals in the UK and options for future application of wider limits at low voltageJul 2017Q1 2022Current £Free Add to Order
Engineering Recommendations (EREC)P5Issue 6 (Revision)Design methods for LV underground networks for new housing developmentsMar 2017Q1 2022Current £45.00 Add to Order
Technical Specifications (TS)43-125 Part 1Issue 2 (Revision)Design guide and technical specification for overhead lines above 45 kV: Part 1 Design basis and electrical requirementsFeb 2017Q1 2022Current £80.00 Add to Order
Technical Specifications (TS)43-125 Part 2Issue 2 (Revision)Design guide and technical specification for overhead lines above 45 kV: Part 2 Conductor systems, insulators and fittingsFeb 2017Q1 2022Current £125.00 Add to Order
Technical Specifications (TS)43-125 Part 3Issue 2 (Revision)Design guide and technical specification for overhead lines above 45 kV: Part 3 - Vibration dampers and spacersFeb 2017Q1 2022Current £65.00 Add to Order
Technical Specifications (TS)43-125 Part 4Issue 2 (Revision)Design guide and technical specification for overhead lines above 45 kV: Part 4 - Lattice steel tower foundations and site requirementsFeb 2017Q1 2022Current £185.00 Add to Order
Technical Specifications (TS)09-6Issue 9 (Revision)

Auxiliary multicore and multipair cables

2017Q1 2022Current £105.00 Add to Order
Engineering Recommendations (EREC)S39Issue 1 (New)General fire precautions in substations at 132 kV and below and in enclosed cableways2017Q1 2022Current £55.00 Add to Order

28 Documents Under Revision

Type     Number     Issue No     Title     Published     Revision Due     Status     Price      
Engineering Recommendations (EREC)G57Issue 1 (New)Cable Laying on Agricultural Land1983Q4 2018Current (Under Revision) £30.00 Add to Order
Engineering Recommendations (EREC)P18Issue 1 (New)Complexity of 132 kV circuits1978Q4 2018Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)G18Issue 3 (Revision)Air Break Switch Disconnectors: RecommendationsNov 2013Q1 2019Current (Under Revision) £45.00 Add to Order
Engineering Recommendations (EREC)G39Issue 2 (Revision)Model code of practice covering electrical safety in the planning, installation, commissioning and maintenance of public lighting and other street furniture2013Q1 2019Current (Under Revision) £55.00 Add to Order
Technical Specifications (TS)43-8Issue 4 (Revision)

Overhead Line Clearances

2015 Current (Under Revision) £80.00 Add to Order
Engineering Recommendations (EREC)G88Issue 2 (Revision)Principles For The Planning, Connection And Operation Of Electricity Distribution Networks At The Interface Between Distribution Network Operators (DNOs) And Independent Distribution Network Operators (IDNOs)2014 Current (Under Revision) £65.00 Add to Order
Engineering Recommendations (EREC)G55Issue 3 (Revision)Safe tree working in proximity to overhead electric lines.Nov 2013 Current (Under Revision) £55.00 Add to Order
Technical Specifications (TS)12-23Issue 3 (Revision)Polyethylene Warning Tape, Polyethylene Protection Tape and Polyethylene Protection Tiles for Buried Electricity Supply Cable2013 Current (Under Revision) £30.00 Add to Order
Engineering Recommendations (EREC)G92Issue 1 (New)Guidelines for industry best practice in relation to Electric and Magnetic Fields (EMFs) in the design and management of low-voltage distribution networks2013 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)G79 Part 2dIssue 2 (Revision)Procedure for the Conformity Assessment of Plant & Products for use by the Energy Networks Association Member Companies Part 2d: General Description and Information for Suppliers of Products and SystemsMar 2012 Current (Under Revision) £65.00 Add to Order
Engineering Recommendations (EREC)G79 Part 1Issue 2 (Revision)Procedure for the Conformity Assessment of Plant & Products for use by the Energy Networks Association Member CompaniesMar 2012 Current (Under Revision) £45.00 Add to Order
Engineering Recommendations (EREC)G79 Part 2aIssue 2 (Revision)Procedure for the Conformity Assessment of Plant & Products for use by the Energy Networks Association Member Companies Part 2a: Procedure for the Conformity Assessment of Switchgear.Mar 2012 Current (Under Revision) £45.00 Add to Order
Technical Specifications (TS)41-36Issue 3 (Revision)Switchgear for service up to 36 kV (Cable and Overhead conductor connected)2012 Current (Under Revision) £285.00 Add to Order
Engineering Recommendations (EREC)P2/6Issue 1 (New)Security of SupplyJul 2006 Current (Under Revision) £Free Add to Order
Technical Specifications (TS)43-40Issue 2 (Revision)Specification for single circuit overhead lines on wood poles for use at high voltage up to and including 33 kV Feb 2004 Current (Under Revision) £125.00 Add to Order
Technical Specifications (TS)48-06-01Issue 1 (New)ENA Protection Assessment - Functional Test Requirements - Distance Protection2004 Current (Under Revision) £45.00 Add to Order
Technical Specifications (TS)48-06-02Issue 1 (New)ENA Protection Assessment - Functional Test Requirements - Feeder Unit Protection2004 Current (Under Revision) £45.00 Add to Order
Technical Specifications (TS)48-06-03Issue 1 (New)ENA Protection Assessment Functional Test Requirements - Transformer Protection2004 Current (Under Revision) £45.00 Add to Order
Engineering Recommendations (EREC)G5/4-1Issue 4 (Revision)Planning Levels for harmonic Voltage Distortion and the Connection of Non-Linear Equipment to Transmission Systems and Distribution Networks in the United KingdomMar 2001 Current (Under Revision) £Free Add to Order
Technical Specifications (TS)09-07Issue 5 (Revision)PVC and XLPE Insulated Concentric service cables with stranded copper or solid aluminium phase conductors and copper concentric neutral conductors1999 Current (Under Revision) £30.00 Add to Order
Technical Specifications (TS)09-22Issue 1 (New)Protection of cable installations against the effects of fire1997 Current (Under Revision) £45.00 Add to Order
Engineering Recommendations (EREC)G74Issue 1 (New)Procedure to meet the requirements of IEC 909 for the calculation of short-circuit currents in three-phase AC power systems1992 Current (Under Revision) £55.00 Add to Order
Engineering Recommendations (EREC)P29Issue 1 (New)Planning limits for voltage unbalance in the UK for 132 kV and below1990 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)P28Issue 1 (New)Planning limits for voltage fluctuations caused by industrial, commercial and domestic equipment in the United Kingdom1989 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)S34Issue 1 (New)

A guide for assessing the rise of earth potential at substation sites

1986 Current (Under Revision) £Free Add to Order
Technical Specifications (TS)41-21Issue 1 (New)Portable earthing equipment for open type HV apparatus in substations1985 Current (Under Revision) £65.00 Add to Order
Technical Specifications (TS)43-81Issue 1 (New)Portable earthing equipment for high voltage overhead lines up to and including 66 kV1984 Current (Under Revision) £30.00 Add to Order
Engineering Recommendations (EREC)P24Issue 1 (New)AC traction supplies to British Rail1984 Current (Under Revision) £Free Add to Order

22 Distribution Code Documents

Type     Number     Issue No     Title     Published     Revision Due     Status     Price      
Technical Specifications (TS)41-24Issue 2 (Revision)

Guidelines for the design, installation, testing and maintenance of main earthing systems in substations

Nov 2018Q4 2023Current £Free Add to Order
Engineering Recommendations (EREC)S34Issue 2 (Revision)

A guide for assessing the rise of earth potential at electrical installations

Nov 2018Q4 2023Current £Free Add to Order
Engineering Recommendations (EREC)G59/3Issue 3 (Revision)

Recommendations for the connection of Generating Plant to the Distribution Systems of Licensed Distribution Network Operators

Jul 2018Q1 2023Current £Free Add to Order
Engineering Recommendations (EREC)P25Issue 2 (Revision)The short-circuit characteristics of single-phase and three-phase low voltage distribution networks2018Q1 2023Current £Free Add to Order
Engineering Recommendations (EREC)G81 Part 1Issue 3 (Revision)Framework for new low voltage housing development installations - Part 1 Design and planning2016Q1 2021Current £Free Add to Order
Engineering Recommendations (EREC)G81 Part 2Issue 2 (Revision)Framework for new low voltage housing development installations - Part 2 Materials specification2016Q1 2021Current £Free Add to Order
Engineering Recommendations (EREC)G81 Part 3Issue 2 (Revision)Framework for new low voltage housing development installations - Part 3 Installation and records2016Q1 2021Current £Free Add to Order
Engineering Recommendations (EREC)G81 Part 4Issue 3 (Revision)Framework for new industrial and commercial underground connections - Part 4 Design and planning2016Q1 2021Current £Free Add to Order
Engineering Recommendations (EREC)G81 Part 5Issue 2 (Revision)Framework for new industrial and commercial underground connections - Part 5 Materials specification2016Q1 2021Current £Free Add to Order
Engineering Recommendations (EREC)G81 Part 6Issue 2 (Revision)Framework for new industrial and commercial underground connections - Part 6 Installation and records2016Q1 2021Current £Free Add to Order
Engineering Recommendations (EREC)G81 Part 7Issue 2 (Revision)Framework for contestable diversionary and reinforcement works not exceeding 33 kV - Part 7 Contestable diversionary and reinforcement works2016Q1 2021Current £Free Add to Order
Engineering Recommendations (EREC)G87Issue 2 (Revision)

Guidelines for the Provision of Low Voltage Connections to Multiple Occupancy Buildings

Jul 2015Q1 2020Current £80.00 Add to Order
Engineering Reports (EREP)130Issue 2 (Revision)Application guide for assessing the capacity of networks containing distributed generationDec 2014Q1 2019Current £Free Add to Order
Engineering Recommendations (EREC)G12Issue 4 (Revision)Requirements for the Application of Protective Multiple Earthing to Low Voltage NetworksNov 2013Q1 2020Current £Free Add to Order
Engineering Reports (EREP)131Issue 2 (Revision)Analysis package for assessing generation security capability - Users' guideDec 2012 Current £Free Add to Order
Engineering Recommendations (EREC)P2/6Issue 1 (New)Security of SupplyJul 2006 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)G5/4-1Issue 4 (Revision)Planning Levels for harmonic Voltage Distortion and the Connection of Non-Linear Equipment to Transmission Systems and Distribution Networks in the United KingdomMar 2001 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)P29Issue 1 (New)Planning limits for voltage unbalance in the UK for 132 kV and below1990 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)P28Issue 1 (New)Planning limits for voltage fluctuations caused by industrial, commercial and domestic equipment in the United Kingdom1989 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)S34Issue 1 (New)

A guide for assessing the rise of earth potential at substation sites

1986 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)P24Issue 1 (New)AC traction supplies to British Rail1984 Current (Under Revision) £Free Add to Order
Engineering Recommendations (EREC)P18Issue 1 (New)Complexity of 132 kV circuits1978Q4 2018Current (Under Revision) £Free Add to Order