EDS 08-2100 LV Customer Supplieslibrary.ukpowernetworks.co.uk/library/asset/26dcfd0d-e8ef-46e9-a155... · DNO Distribution Network Operator EHV Voltages above 11kV. These may be both

Document Number: EDS 08-2100

Version: 7.0

Date: 11/12/2018

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ENGINEERING DESIGN STANDARD

EDS 08-2100

LV CUSTOMER SUPPLIES

Network(s): EPN, LPN, SPN

Summary: This standard provides guidance on the provision of LV supplies between 100A and 2165A (23kVA to 1.5MVA).

Author: Stephen Cuddihey Date: 11/12/2018

Approver: Paul Williams Date: 14/12/2018

This document forms part of the Company's Integrated Business System and its requirements are mandatory throughout UK Power Networks. Departure from these requirements may only be taken with the written approval of the Director of Asset Management. If you have any queries about this document please contact the author or owner of the current version.

Circulation

UK Power Networks External

☒ Asset Management ☒ UK Power Networks Services

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LV Customer Supplies Document Number: EDS 08-2100

Version: 7.0

Date: 11/12/2018

© UK Power Networks 2018 All rights reserved 2 of 45

Revision Record

Version 7.0 Review Date 20/12/2022

Date 11/12/2018 Author Stephen Cuddihey

Reason for update: Document reviewed and updated to provide further clarification on the provision of large LV supplies.

What has changed:

Flow chart moved to Section 5.

Clarification of the use of 630A fuses in Sections 8 and 10.

Additional guidance for existing LV supplies in Section 13.

Clarification of the maximum service length for 100A supplies in Sections 6 and 12.

Guidance on generator connection expanded in Section 14.15.

Service intake positions clarified in Section 14.9.



Reason for change: Re-alignment of LV design standards.

What has changed:

Correction of kVA figures in Table 5-1 (Section 5) and Table 7-1 (Section 7).

Introduction of 1500kVA services (Section 11).

Three-phase SNE services from substation/pillar added (Section 12).

Introduction of LV supplies flowchart

References to LV design standards updated throughout.

Document renumbered from EDS 08-0143 to EDS 08-2100.



Reason for change: Response to internal consultation

What has changed: Table 5-1 and Table 8-1 have been updated to remove copper waveform cables and amend the fuse sizes used in 200A and 400A cut-outs. Pup busbar comment in section 7 now removed.



Reason for change: Periodic review and to ensure consistency with other standards.

What has changed:

Reference to 1600A replaced with 1440A throughout.

New Section 6 added for 100A Single phase supplies to metal framework buildings and guidance added to Sections 7 and 8.

ESQCR requirements now added to Sections 7 and 8.

New LV board supplies without boundary metering point now covered in Section 11.

Metal Framework guidance added to Section 12.3.

Fuse downgrades addressed in Section 12.4.

EDS 08-0118 addendum incorporated into Section 12.7.

New existing supply arrangements now covered in Section 13.

New disconnection guidance covered in Section 14.

Document title amended.


Version: 7.0

Date: 11/12/2018


Contents

1 Introduction ............................................................................................................. 5

2 Scope ....................................................................................................................... 5

3 Guidance on BS7671 (IET Requirements for Electrical Installation) .................... 5

4 Glossary and Abbreviations ................................................................................... 6

5 New Supply Arrangements ..................................................................................... 7

6 100A Three-phase and Neutral Supplies ............................................................... 9

7 200A to 400A Three-phase and Neutral Supplies ................................................ 11

8 400A to 800A Three-phase and Neutral Supplies ................................................ 14

9 800A to 1440A Three-phase and Neutral Supplies .............................................. 17

10 315A to 1440A Three-phase and Neutral Supplies – Unmetered LV Way .......... 21

11 1440A to 2165A Three-phase and Neutral Supplies ............................................ 23

12 SNE Supplies ......................................................................................................... 27

13 Existing Supply Arrangements – Modifications .................................................. 30

14 General Requirements .......................................................................................... 31

15 Disconnections ...................................................................................................... 43

16 References ............................................................................................................. 44

17 Dependent Documents.......................................................................................... 45

Tables

Table 5-1 – Standard Supply Sizes for Customer Loads ....................................................... 8

Table 6-1 – 100A Three-phase Supply Arrangement ............................................................ 9

Table 7-1 – 200A to 400A Three-phase Supply Arrangements ........................................... 11

Table 8-1 – 400A to 800A Three-phase Supply Arrangements ........................................... 14

Table 9-1 – 800A to 1440A Three-phase Supply Arrangements ......................................... 17

Table 10-1 – 400A to 800A Three-phase Supply Arrangements ......................................... 21

Table 11-1 – 1440A to 2165A Three-phase Supply Arrangements...................................... 23

Table 12-1 – 100A Single Phase to 100A Three-phase SNE Supply Arrangements ........... 28

Table 12-2 – 200A to 400A Three-phase SNE Supply Arrangements ................................. 29


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Date: 11/12/2018


Figures

Figure 5-1 – LV Supplies Flowchart ...................................................................................... 7

Figure 6-1 – New Service from an Existing LV Main with Whole Current Metering .............. 10

Figure 7-1 – New service from an Existing LV Main with CT, Private and Settlement Metering ............................................................................................................ 12

Figure 7-2 - A New Service from a Dedicated LV Way with CT Metering, Private Metering and Settlement Metering .................................................................................... 13

Figure 7-3 - A New Service from a Dedicated LV Way with Full Settlement Metering.......... 13

Figure 8-1 - A New Service from a CT Metered TMFC with Private Metering and Settlement Metering ............................................................................................................ 16

Figure 8-2 - A New Service from a CT Metered TMFC with Full Settlement metering, CT Metering Disconnected ...................................................................................... 16

Figure 9-1 - A New Service from a CT Metered ACB with Private Metering and Settlement Metering ............................................................................................................ 19

Figure 9-2 - A New Service from a CT Metered ACB with Private Metering and both Whole Current and CT Metered Settlement Metering (Exit Point CT Chamber is Not Owned by UK Power Networks) ......................................................................... 19

Figure 9-3 - A New Service from a CT Metered ACB with Full Settlement Metering CT Metering Disconnected ...................................................................................... 20

Figure 10-1 - New Service from a TMFC or LV Board with Full Settlement Metering........... 22

Figure 11-1 - A New Service from a CT Metered ACB with Private Metering and Settlement Metering ............................................................................................................ 25

Figure 11-2 - A New Service from a CT Metered ACB with Private Metering and both Whole Current and CT Metered Settlement Metering (Exit Point CT Chamber is Not Owned by UK Power Networks) ......................................................................... 25

Figure 11-3 - A New Service from a CT Metered ACB with Full Settlement Metering CT Metering Disconnected ...................................................................................... 26

Figure 12-1 – 100A SNE Services to Commercial and Industrial Units ................................ 27

Figure 12-2 – 200A to 400A SNE Services to Commercial and Industrial Units................... 27

Figure 13-1 – Typical conversions for 100A Single Phase Customers ................................ 30

Figure 14-1 – LV Generator Earthing for Parallel Operation Only ........................................ 38

Figure 14-2 – LV Generator Earthing for Standby Operation ............................................... 39

Figure 14-3 – LV Generator Earthing for Parallel Operation ................................................ 39

Figure 14-4 - LV Generator Earthing for Standby Operation Only – Mains Supply .............. 40

Figure 14-5 - LV Generator Earthing for Standby Operation Only – Generator Supply ........ 40


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Date: 11/12/2018


1 Introduction

This standard provides guidance on the provision of LV supplies between 100A and 2165A (23kVA to 1.5MVA). It also provides guidance for 100A single-phase and three-phase large LV supplies to shared metal framework buildings.

A range of LV service arrangements and different types of cable may be encountered across UK Power networks three licence areas. This standard defines the installation of new large LV services and alterations to existing services.

2 Scope

This standard applies to new and increased capacity LV supplies (except IDNOs), where a capacity of more than 100A per phase is required in EPN, LPN and SPN.

Supplies of more than 1500kVA to a single customer shall be provided at HV (refer to EDS 08-3100).

For supplies to properties with no shared metallic framework up to 100A single-phase refer to EDS 08-2101.

For guidance on multi-occupied buildings refer to EDS 08-1103.

The LV supply arrangements to a licensed distribution system i.e. Inset Network (IDNOs) are detailed in EDS 08-0113 and should be read in conjunction with this standard.

3 Guidance on BS7671 (IET Requirements for Electrical Installation)

UK Power Networks is not an enforcing or advisory body for BS 7671. Where questions of the adequacy of the customer’s installation need to be resolved the electrical contractor should seek advice from the trade body providing his accreditation e.g. Electrical Contractors Association (ECA), National Inspection Council for Electrical Installation Contracting (NICEIC) etc.

Arrangement of the customer installation is entirely at the discretion of the customer. Legislation requires that the customer installation shall be provided, installed and maintained in accordance with BS 7671 by the customer’s electrical contractor.


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4 Glossary and Abbreviations

Term Definition

ACB Air Circuit Breaker

BNO Building Network Operator

CHLDZ Central High Load Density Zone, for example the City of London.

CT/CT metering Current Transformer / Current Transformer metering

DNO Distribution Network Operator

EHV Voltages above 11kV. These may be both transmission and distribution networks depending on location and requirement

Full Settlements Metering

A method of metering provision; metering is applied to the exit points within a building network.

GRP Glass Reinforced Plastic

HV Voltages above 1000V; generally used to describe 11kV or 6.6kV distribution systems but may include higher or other legacy voltages.

ICP Independent Connection Provider

IDNO Independent Distribution Network Operator who holds a Distribution License

LV Voltages up to 1000V; generally used to describe 230/400V or 230/460V distribution systems

MPAN Metering Point Administration Number. A unique number for each Metering Point, issued by the relevant licensed distributor for use in the settlement system

MPR Maximum Power Requirement

MSDB Multi-Service Distribution Board

Partial Settlements Metering

A method of metering provision; formally known as “difference metering”, this is metering is applied to both the boundary point of supply and to exit points within a building network, though not all points. Exit point meter readings are subtracted from the boundary meter and customers billed accordingly

PLTU Parasitic Load Tripping Unit: A device at HV supply points that senses the presence of a back-fed HV earth fault condition and trips the parasitic load connected to the feeder

PME Protective Multiple Earthing. PME is the most common form of earthing provided at new installations. A single conductor for neutral and earthing functions is utilised and an earth terminal is provided at the customer’s installation.

TMFC Transformer Mounted Fused Cabinet

TN-S Terre Neutral Separated

TPN Three-phase and Neutral

Whole Current Metering

Whole current metering: normally reserved for smaller loads and cables where load can be safely passed through a metering device; the device is installed in line with the incoming supply and takes a direct measurement of the incoming supply


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5 New Supply Arrangements

The following flow chart and table provides a summary of the supply arrangements appropriate for the varying levels of customer demand.

LV Supply Request

New building or complete refurb?

Yes BNO?

Yes

No

Industrial units or terrace houses?

No YesSteel-frame

or shared metallic services?

YesNo

No

Single-phase supplies?

Individual PME services

(EDS 08-2101 or EDS 08-2100)

Yes

No

Individual SNE services from on-site

substation (EDS 08-2100)

or individual CNE services with TT

earthing(EDS 08-2101 or

EDS 08-2100)

PME to kiosk and individual SNE

services (EDS )8-2100)

or individual CNE services with TT

earthing(EDS 08-2100)

Multi-ocupplied building?

No

Yes

Single PME service(EDS 08-2101)

No

Customer to appoint BNO

(EDS 08-1103)

Unmetered supply?

No

25A PME service(EDS 08-2102)

Yes

Single service upgrade?

Replace existing service with new

service on a like-for-like basis

(EDS 08-2100)

Yes

Yes

Single-phase supply?

Single PME service(EDS 08-2100)

No

Yes

Single intake position with a single PME service or multiple

bonded three-phase PME services

(EDS 08-2101 orEDS 08-2100)

Single intake position

possible?No

Yes

Steel-frame or shared metallic

services?

Yes

Replace existing single-phase service with new three-phase

service(EDS 08-2100)

Single-phase existing service?

Yes

NoNo

Retain existing service and add a new PME service(EDS 08-2101 or

EDS 08-2100)

New intake position within 5 metres for new single PME

service bonded to existing PME service

(EDS 08-2100)

Communal or landlord supply

required?

Single service to single intake position or kiosk

(EDS 08-2100)

Flats with individual entrances

(no communal area)?

Yes

Modification to existing building?

Yes

No

Existing service to be moved or

multiple services requested?

NoNo

No

Separate building cores?

YesSingle SNE service

to single intake position in each

core(EDS 08-2100)

Customer to appoint BNO

(EDS 08-1103)

Yes

Single service to single intake position

or kiosk(EDS 08-2100)

Separate building cores?

Yes

Single SNE service to single intake

position in each core(EDS 08-2100)

No

No

Figure 5-1 – LV Supplies Flowchart


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Table 5-1 – Standard Supply Sizes for Customer Loads

MPR (kVA) Service Cable Rating and Termination

Max. Fuse Rating (A)

Section

1 - 23 35mm² Single-phase Al Split Concentric† or Concentric

100A Single-phase cut-out

100 EDS 08-2101

24 - 69 35mm² Three-phase Al Concentric

100A Three-phase cut-out

100 6

70 - 138 95mm² Three-phase Al Waveform


200 7



315 7



400 7

24 - 69 35mm² Three-phase Al Split Concentric†


100 12

70 - 138 95mm² Four Core (SNE) Three-phase Aluminium Waveform†


200 12



315 12



400 12

278 - 315 Customer Cables*† 800A LV Way 630 8

316 - 555 800A LV Way 800 8

400A LV Ways 2 x 400‡ 10

556 - 1000 1600A ACB n/a 9

400A LV Ways 4 x 400‡ 10

1001 - 1500 Customer Cables*‡† 2500A ACB n/a 11

1500+ Supplies of greater than 1500kVA shall not be provided at LV. Refer to EDS 08-3100 and EDS 08-4100

* Cables to be specified and provided by the Customer. Refer to ECS 03-0054 for typical cable sizes and terminations. Customer cable supplies may be provided to shared metallic framework buildings.

‡ Full settlements metering required, 630A fuse also available, refer to section 10.

† Indicates a supply suitable for steel framed buildings

For further guidance on the provision of LV supplies, please refer to the LV flowchart in Figure 5-1


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6 100A Three-phase and Neutral Supplies

6.1 Supply Termination

A 100A three-phase and neutral (TPN) supply shall be provided via 35mm2 three-phase service cable terminated into a three-phase 100A cut-out (refer to EAS 13-0000) as detailed in Table 6-1.

Table 6-1 – 100A Three-phase Supply Arrangement

MPR (kVA)

Service Cable Rating and Termination


24 - 69 35mm² Three-phase Aluminium Concentric


100

CT metering is not available for 100A TPN supplies; these shall be whole current, full settlements metered.

The service length shall be limited to 43m to ensure a maximum voltage drop of 6% at the end customer supply terminals. This may require consultation with other network operators to ensure ESQCR compliance.

6.2 Ownership Boundary

As full settlements metering is required, the ownership boundary shall be at the outgoing terminals of the cut-out.

The ownership boundary shall be indicated on site by the use of the approved boundary label EDS 07-0009.147 (refer to EAS 07-0021).

6.3 Customer Cables

The customer shall provide, install and maintain the LV tails with suitable trunking as per BS 7671 from either the metering points of isolation or a single point of isolation from the outgoing terminals of the cut-out.

The point of isolation may be an isolating switch, a fuse or link in a cut-out, either integral to the intake position, distribution equipment or a standalone device.

Armoured and Tri-rated cables shall not be terminated into a 100A TPN cut-out.


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6.4 Metering Diagram

An indicative metering diagram is shown in Figure 6-1.

Ownership boundary

UK Power

Networks

Customer

New UK Power Networks 35 mm2 service cable

Customer point of isolation

100A TPN cut-out

SM SM SM SMSM: Settlements meter i.e.

MPAN and supplier meter

Existing LV main

Meter operator

Figure 6-1 – New Service from an Existing LV Main with Whole Current Metering


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7 200A to 400A Three-phase and Neutral Supplies


A 200A to 400A three-phase and neutral (TPN) supply shall be provided via the appropriate service cable as detailed in Table 7-1 and terminated into a heavy duty cut-out (refer to EAS 13-0000) connected to a CT chamber (refer to EAS 13-0000) if required (refer to Section 14.7).

Table 7-1 – 200A to 400A Three-phase Supply Arrangements

MPR (kVA)



70 - 138 95mm² Three-phase Aluminium Waveform


200



315



400

The incoming duct, cable, earth-wire and cut-out standard arrangement for a basement intake are shown in EDS 08-2110.

All cut-outs shall use bottom entry as standard. New supplies shall not be provided with a top entry cut-out.

The service length shall be limited to ensure a maximum voltage drop of 6% at the end customer supply terminals. This may require consultation with other network operators to ensure ESQCR compliance.


The ownership boundary shall be at either:

Partial settlements: the outgoing terminals of the CT cabinet.

Full settlements: the outgoing terminals of the cut-out.



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7.3 Customer Cables

The customer shall provide, install and maintain the LV tails with suitable trunking as per BS 7671 from the customer’s point of isolation to the outgoing terminals of the cut-out or CT chamber if one is required.


Armoured and Tri-rated cables shall not be terminated into a 200A to 400A TPN cut-out.

7.4 Metering Diagrams

Indicative metering diagrams are shown in Figure 7-1 to Figure 7-3.

Ownership boundary

CTs

UK Power

Networks

Customer

New UK Power Networks service cable up to 300 mm2


200A to 400A

TPN cut-out

Existing LV Main cable

SM: Settlements meter i.e. MPAN

and supplier meter

PM: Private meter i.e. no MPAN

and private network operator

PM PM PM SM

Partial settlements metering

Test block or

front of CT

panel

Meter operator

SM

Figure 7-1 – New service from an Existing LV Main with CT, Private and Settlement Metering


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New UK Power Networks

dedicated LV way

630A LV ways

Distribution substation

Ownership boundary

UK Power

Networks

Customer Customer point of isolation

SM: Settlements meter i.e.

MPAN and supplier meter

PM: Private meter i.e. no MPAN

and private network operator

PM PM PM SM


200A to 400A TPN cut-out

CTs

Test block or

front of CT

panel

Meter

operator

SM

Figure 7-2 - A New Service from a Dedicated LV Way with CT Metering, Private Metering and Settlement Metering

630A LV ways


Ownership boundary

UK Power

Networks

Customer


SM SM SM SM

Full settlements metering

New UK Power Networks

dedicated LV way

200A to 400A TPN cut-out

Meter

operator

Figure 7-3 - A New Service from a Dedicated LV Way with Full Settlement Metering


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A 400A to 800A three-phase and neutral (TPN) supply shall be provided from an on-site substation with a minimum 800kVA transformer via either an 800A 5-way TMFC or an 800A LV board extension as detailed in Table 8-1.


MPR (kVA)



278 - 315 Cables to be specified and provided by the Customer. Refer to ECS 03-0054 for typical cable sizes and terminations

800A LV Way 630

316 - 555 800A LV Way 800

Note: The 800kVA transformer is required as it is not possible to equip a substation of less than 800kVA with an

800A way due to network protection discrimination.

Both TMFC and LV board extension are equipped with integral metering CTs on the outgoing (load) side (refer to ECS 03-0054).

This supply arrangement requires an on-site substation. The substation shall be directly adjacent to the customer’s supply intake position and where practicable at a boundary location with access from the public highway.

Note: The 800A way occupies two LV ways, leaving three LV ways for LV network use on a 5-way TMFC.


The ownership boundary shall be at the outgoing terminals of the TMFC or LV board extension.


8.3 Customer Cables

The customer shall provide, install, own and maintain the cable from the TMFC or LV board.

The cables shall be of a type suitable for termination in the TMFC or LV board (refer to ECS 03-0054). Customer cables shall be selected and installed in accordance with BS 7671.

Armoured cables are acceptable for TMFC or LV board terminations. The armour shall be terminated at the customer side only and shall be secured in a plastic gland within the substation.

The minimum cross sectional size of the neutral conductor shall be the same size as phase conductors. Alternatively the cross sectional size can be determined in accordance with BS 7671 Regulation 524.2.


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The minimum cross sectional size of a copper earth conductor shall be half the size of the phase conductors in accordance with BS 7671 Regulation 543.1.4. Alternatively the cross sectional size can be calculated in accordance with BS 7671 Regulation 543.1.3.

The customer shall:

Advise UK Power Networks of the number and size of LV tails to be installed so that the civil works can be designed accordingly.

Fit suitable termination lugs onto their cables. These shall be provided by UK Power Networks – refer to ECS 03-0054.

Provide appropriate physical protection for the cables between the ownership boundary and the customer’s point of isolation in accordance with BS7671.

The customer cables shall be terminated in the LV equipment within the substation by UK Power Networks or suitably authorised ICP staff.



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Indicative metering diagrams are shown in Figure 8-1 and Figure 8-2.


directly adjacent to

supply intake position 600A or

800A

fuse way TMFC


PM PM PM SM


Ownership boundary

UK Power

Networks

Customer

SM

CTs

Test

block

Meter operator

Figure 8-1 - A New Service from a CT Metered TMFC with Private Metering and Settlement Metering



supply intake position

600A or 800A

fuse way TMFC

Ownership boundary

UK Power

Networks

Customer


SM SM SM SM


Meter operator

Figure 8-2 - A New Service from a CT Metered TMFC with Full Settlement metering, CT Metering Disconnected


Version: 7.0

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An 800 to 1440A three-phase and neutral (TPN) supply shall be provided via an ACB in a 5-way TMFC with a spare 630A way and equipped with integral metering CTs on the outgoing (load) side (refer to ECS 03-0054) as detailed in Table 9-1.


MPR (kVA)




1600A ACB n/a

This supply arrangement requires a dedicated on-site substation. The substation shall be directly adjacent to the customer’s supply intake position and where practicable at a boundary location with access from the public highway. Refer to Section 14.2.

Note: The single spare 630A LV way may be used for limited LV backfeed to the customer property where feasible.


The ownership boundary shall be at the outgoing terminals of the ACB.


9.3 Customer’s Cables

The customer shall provide, install, own and maintain the cable from the ACB.

The cables shall be of a type suitable for termination in the ACB (refer to ECS 03-0054). Customer cables shall be selected and installed in accordance with BS 7671.

Armoured cables are acceptable for the ACB terminations. The armour shall be terminated at the customer side only and shall be secured in a plastic gland within the substation.



The maximum length of the cables will be determined by the need to ensure that the ACB provides the required protection for the cables in the event of an earth fault.


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The customer shall:



Provide an appropriate sized earthing conductor from the main earth bar of the customer LV installation to a UK Power Networks LV earth terminal.



The point of isolation may be an isolating switch, a fuse or link in a cut-out, either integral to the intake position, distribution equipment, circuit breaker or a standalone device.

9.4 Control and Protection

It is the customer’s responsibility to ensure that the characteristics of the ACB provide effective short circuit protection for the size of LV tails selected.

The customer shall ensure that an LV fault at any point up to the customer’s first circuit breaker or fuse will trip the ACB within five seconds.

Standard protection settings for the ACB are specified in EDS 05-2011 in order to provide the maximum grading margins for customer’s protection, while ensuring discrimination with the HV protection.

UK Power Networks shall provide a copy of the applicable ACB protection settings and the maximum earth loop impedance value at the ACB terminals to the customer.

9.5 Emergency Tripping

ACB emergency trip facilities may be provided in accordance with EDS 05-0002 at customer request.




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TMFCACB

Customer

point of

isolation

PM PM PM SM


CTs

Ownership boundary

UK Power Networks

Customer

Meter operatorSM

Test

block

Figure 9-1 - A New Service from a CT Metered ACB with Private Metering and Settlement Metering




TMFC

Customer provided CT chamber to be arranged with meter operator

ACB

Customer

point of

isolation

PM PMSM


CTs

Ownership boundary

UK Power Networks

Customer

Meter operatorSM

Test

block

SM

Test

BlockCTs

Figure 9-2 - A New Service from a CT Metered ACB with Private Metering and both Whole Current and CT Metered Settlement Metering (Exit Point CT Chamber is Not Owned by UK Power Networks)


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TMFCACB

Customer

point of

isolation

SM SM SM SM


Ownership boundary

UK Power Networks

Customer

Meter operator

Figure 9-3 - A New Service from a CT Metered ACB with Full Settlement Metering CT Metering Disconnected


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10 315A to 1440A Three-phase and Neutral Supplies – Unmetered LV Way


As an alternative to the supply arrangements in the previous sections a 315A to 1440A three-phase and neutral (TPN) supply may be provided from an on-site substation via either a 5-way or 7-way TMFC or LV board.

The LV ways shall be fused in accordance to EDS 05-4001, as detailed in Table 10-1.


MPR (kVA)




Single 400A LV Way 315

219 - 277 Single 400A LV Way 400

278 - 555 Dual 400A LV Ways 400

556 - 1000 Four 400A LV Ways 400

Note: 630A LV ways may be used for up to 436kVA per LV way where hardware and network fuse discrimination

allows.

Full settlements metering by the customer shall be required, refer to Section 14.7.

Multiple supplies from a TMFC or LV board shall be installed and suitably protected to preclude any possibility of parallels across UK Power Networks’ network, to prevent the passage of fault current through a customer’s equipment, overload of incoming supplies, and the inadvertent electrification of a network deemed to be isolated.

This supply arrangement requires an on-site substation. The substation shall be immediately adjacent to the customer’s supply intake position and where practicable at a boundary location with access from the public highway. Refer to Section 14.2.


The ownership boundary shall be at the outgoing terminals of the TMFC or LV board.


10.3 Customer Cables

The customer shall provide, install, own and maintain the cable from the TMFC or LV Board.

The cables shall be of a type suitable for termination in the TMFC or LV board (refer to ECS 03-0054). Customer cables shall be selected and installed in accordance with BS 7671.

Armoured cables are acceptable for TMFC or LV board terminations. The armour shall be terminated at the customer side only and shall be secured in a plastic gland within the substation.


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The customer shall:






10.4 Metering Diagram

An indicative metering diagram is shown in Figure 10-1.




400A fuse way TMFC

or LV

Board Ownership boundary

UK Power

Networks

Customer


SM SM SM SM


Meter operator

Figure 10-1 - New Service from a TMFC or LV Board with Full Settlement Metering


Version: 7.0

Date: 11/12/2018




A 1440 to 2165A three-phase and neutral (TPN) supply shall be provided via an ACB in a 5-way TMFC (refer to ECS 03-0054) as detailed in Table 11-1.


MPR (kVA)



1001 - 1500

Cables to be specified and provided by the Customer. Refer to ECS 03-0054 for typical cable sizes and terminations

2500A ACB n/a

This supply shall only be used for a single customer (e.g. BNO, TBS etc.) and be provided from a ringed connection via a dedicated on-site substation. The substation shall be free-standing brick-built or integral type and immediately adjacent to the customer’s supply intake position with direct access from the public highway. Refer to Section 14.2.

Note 1: GRP and basement substations are not suitable to house a 1500kVA transformer.

Note 2: It is not be possible to provide a 30% outage capacity in accordance with EDS 08-3000 for 1440A - 2165A

supplies.


The ownership boundary shall be at the outgoing terminals of the ACB.


11.3 Customer’s Cables

The customer shall provide, install, own and maintain the cable from the ACB.

The cables shall be of a type suitable for termination in the ACB (refer to ECS 03-0054). Customer cables shall be selected and installed in accordance with BS 7671.

Armoured cables are acceptable for the ACB terminations. The armour shall be terminated at the customer side only and shall be secured in a plastic gland within the substation.

The minimum cross sectional size of the neutral conductor shall be the same size as phase conductors.


The maximum length of the cables will be determined by the need to ensure that the ACB provides the required protection for the cables in the event of an earth fault.


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The customer shall:



Provide an appropriate sized earthing conductor from the main earth bar of the customer LV installation to a UK Power Networks LV earth terminal.



The point of isolation may be an isolating switch, a fuse or link in a cut-out, either integral to the intake position, distribution equipment, circuit breaker or a standalone device.

11.4 Control and Protection

It is the customer’s responsibility to ensure that the characteristics of the ACB provide effective short circuit protection for the size of LV tails selected.

The customer shall ensure that an LV fault at any point up to the customer’s first circuit breaker or fuse will trip the ACB within five seconds.

Standard protection settings for the ACB are specified in EDS 05-2011 in order to provide the maximum grading margins for customer’s protection, while ensuring discrimination with the HV protection.

UK Power Networks shall provide a copy of the applicable ACB protection settings and the maximum earth loop impedance value at the ACB terminals to the customer.

11.5 Emergency Tripping

ACB emergency trip facilities may be provided in accordance with EDS 05-0002 at customer request.




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immediately adjacent to


TMFCACB

Customer

point of

isolation

PM PM PM SM


CTs

Ownership boundary

UK Power Networks

Customer

Meter operator

SM

Test block

Figure 11-1 - A New Service from a CT Metered ACB with Private Metering and Settlement Metering


immediately adjacent to

supply intake position TMFC

Customer provided CT chamber to be arranged with meter operator

ACB

Customer

point of

isolation

PM PMSM


CTs

Ownership boundary

UK Power Networks

Customer

Meter operatorSM

Test block

SM

Test Block

CTs

Figure 11-2 - A New Service from a CT Metered ACB with Private Metering and both Whole Current and CT Metered Settlement Metering (Exit Point CT Chamber is Not Owned by UK Power Networks)


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immediately adjacent

to supply intake

position

TMFCACB

Customer

point of

isolation

SM SM SM SM


Ownership boundary

UK Power Networks

Customer

Meter operator

Figure 11-3 - A New Service from a CT Metered ACB with Full Settlement Metering CT Metering Disconnected


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12 SNE Supplies

12.1 Overview

SNE supplies may be provided to industrial and commercial units that share a common steel frame or have common metallic services, where they are to be supplied directly by UK Power Networks (with no building network operator – refer to EDS 08-1103) and the supply arrangements in the previous sections are not suitable.

These supply arrangements are shown in Figure 12-1 and Figure 12-2.

UK Power Networks main

CNE cable terminating into cut-out

within intake pillar PME earth electrode

External SNE cables

Each customer responsible

for their own installation

UK Power Networks

PME earth electrode

Private Land Boundary

Figure 12-1 – 100A SNE Services to Commercial and Industrial Units

Dedicated Substation

External SNE Cables

Each Customer

Responsible for their

own Installation

UK Power Networks

Private Land Boundary

Figure 12-2 – 200A to 400A SNE Services to Commercial and Industrial Units


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12.2 100A Single Phase and TPN SNE Supply Termination

A 100A single-phase or 100A three-phase and neutral (TPN) and separate earth supply shall be provided using the appropriate service cable from Table 12-1. The SNE service shall be supplied from a 10-way MSDB with incoming fuse links (refer to EAS 13-0000) and be terminated into a single-phase red head cut-out (refer to EAS 13-0000) in an approved external meter box (refer to EDS 08-2101).

Table 12-1 – 100A Single Phase to 100A Three-phase SNE Supply Arrangements

MPR (kVA)

Service Cable Rating and Termination Max. Fuse Rating (A)

1 - 23 Max. 10 x 35mm² Single-phase Al Split Concentric or Concentric

100A Single-phase cut-out 100

24 - 69 Max. 3 x 35mm² Three-phase Al Split Concentric

100A Three-phase cut-out 100

The MSDB shall be installed within an approved pillar provided by the site developer in accordance with EDS 08-2110.

The MSDB can provide a maximum of ten direct supplies to customers. The incoming CNE cable and incoming fuse shall be sized in accordance with the total diversified load of the supplied properties (refer to EDS 08-2000 for further guidance).

A PME earth electrode shall be installed at the MSDB.

Note: SNE services shall only be provided externally on private land and shall not be used in the public highway.

SNE services shall not be used for unmetered supplies from a metered connection. SNE services shall be identified on all operational LV diagrams and maps.

The service length shall be limited to 43m to ensure a maximum voltage drop of 6% at the customer supply terminals. This may require consultation with other network operators to ensure ESQCR compliance.

12.3 200A-400A TPN SNE Supply Termination

A 200A to 400A three-phase and neutral (TPN) and separate earth supply shall be provided using the appropriate service cable from Table 12-2. The service shall be provided directly from an TMFC, LV board or LV pillar and terminated into a heavy duty cut-out (refer to EAS 13-0000) connected to a CT chamber (refer to EAS 13-0000) if required (refer to Section 14.7).

The supplies shall be provided from an on-site substation via either a 5-way or 7-way TMFC or LV board or an LV pillar located adjacent to the substation. The on-site substation shall be located centrally to the customer supply intake positions and where practicable at a boundary location with access from the public highway.


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Table 12-2 – 200A to 400A Three-phase SNE Supply Arrangements

MPR (kVA)

Service Cable Rating and Termination Max. Fuse Rating (A)

70 - 138 95mm² Four Core Three-phase Aluminium Waveform






The incoming duct, cable, earth-wire and cut-out standard intake arrangements are shown in EDS 08-2110.

All cut-outs shall use bottom entry as standard. New supplies shall not be provided with a top entry cut-out.

The service length shall be limited to ensure a maximum voltage drop of 6% at the end customer supply terminals. This may require consultation with other network operators to ensure ESQCR compliance.

Note: SNE services shall only be provided externally on private land and shall not be used in the public highway.

SNE services shall not be used for unmetered supplies from a metered connection. SNE services shall be identified on all operational LV diagrams and maps.


As full settlements metering is required, the ownership boundary shall be at the outgoing terminals of the red head cut-out (100A supplies) or the cut-out (200A to 400A supplies).


12.5 Customer Cables

The customer shall provide, install and maintain the LV tails with suitable trunking as per BS 7671 from the customer’s point of isolation to the outgoing terminals of the cut-out or CT chamber if one is required.


Armoured and Tri-rated cables shall not be terminated into a TPN cut-outs.


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13 Existing Supply Arrangements – Modifications

It is not intended that the provisions of this standard are applied retrospectively to existing installations.

Where an existing building is to be modified and no increase or decrease of the maximum power requirement is necessary, the opportunity to apply the principles described in this design standard should be taken if possible.

Where an existing building requires an increase or decrease of the maximum power requirement beyond the capability of the existing supply equipment (including service cable and cut-out) but within the scope of this design standard, the existing supply equipment shall be removed and the appropriate supply from Sections 6 to 10 shall be used.

Where additional LV supplies from Sections 6 and 7 are to be provided to an existing building, refer to Section 14.9. Where 100A single phase supplies from EDS 08-2101 are to be augmented and a supply from Section 6 is not appropriate then an additional single phase supply shall be considered. Typical variations to existing arrangements are demonstrated below in Figure 13-1:

SM

SM

SM SM SM

Flat Flat B Flat B

Shop Flat AFlat A

SM

Full settlements

metering

UK Power

Networks

Meter Operator

Ownership Boundary

Figure 13-1 – Typical conversions for 100A Single Phase Customers


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14 General Requirements

These requirements apply to all types of connection governed by this standard

14.1 Construction, Design and Management

The current CDM Regulations remain paramount at all stages of the design process, including requirements to identify, remove or reduce risk at the design stage and the need to liaise with other designers to develop safe designs. This will require a detailed assessment of access/egress arrangements and the safe use of the site as a place of work (refer to EDS 07-3101).

14.2 Substation

For supplies covered within Sections 8, 9, 10 and 11 UK Power Networks or an ICP shall ensure at the point of first contact with the customer that the need for a substation on site is recognised by the customer.

Where a new substation is required to provide the supplies detailed in this standard it shall be provided in accordance with EDS 08-2000. Any remote control and PLTU functionality shall be provided and commissioned at the same time as the substation.

Dedicated substations without LV interconnection which supply customers in the CHLDZ shall be fitted with a PLTU.

LV networks within National Grid sites shall always be supplied by a dedicated substation, refer to EDS 08-2108.

14.2.1 Substation Design

The type, location and access arrangements of the new customer substation shall comply with EDS 07-3101. 24 hour access requirements for personnel and plant shall be available. The substation shall be suitably located at ground level. There shall be adequate provision for installation and maintenance of cables. The proposed site shall be a safe place of work.

The substation design shall comply with EDS 07-3102.

14.2.2 Access Requirements

14.2.2.1 UK Power Networks and/or ICP Entry

As outlined in Section 14.2.1 UK Power Networks staff, representatives or ICPs with appropriate authorisation shall be provided with full access to the UK Power Networks substation. Expected activities are:

To lay incoming cables into the substation.

To install plant and equipment in the substation.

To install the metering termination box and the multicore cable from the substation.

To operate in an emergency.

14.2.2.2 Customer Entry

No customer operational access to UK Power Networks substations shall be provided.


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14.2.2.3 Meter Operator Entry

The customer shall provide access for the meter operator to the metering termination box to install the meter and for routine reading and inspection of the meter.

No access to the substation shall be provided by UK Power Networks for the meter operator.

14.3 Cable Entry Ducts and Trays

UK Power Networks cable entry to the building or cabinet shall be via 125mm or 150mm inside diameter rigid duct(s) (refer to EAS 02-0000).

The provision of a 150mm duct will facilitate up to a 300mm Service upgrade in the future and is at the discretion of the customer.

The ducts shall extend to a position clear of the building and any concreted area. The ducts shall be buried to a minimum depth of 450mm.

Approved 125mm or 150mm entry ducts with a non-corrosive draw cord shall be provided by the developer or customer (refer to EDS 08-2110).

Ducts to be provided by the developer under hard standings on route shall be 125mm minimum inside diameter. If ducts are used over a 40 metre or greater run the ducts shall be 150mm inside diameter. If the route is not straight then draw pits (refer to EDS 08-2110) shall be provided to enable the cables to be installed. Ducts shall be sealed against the ingress of water and gas.

LV cable minimum duct sizes and bending radii are shown in EDS 08-2110 and ECS 02-0019.

For BNO cables refer to EDS 08-1103.

14.4 Earthing

The earthing arrangements on the LV network and at the ownership boundary are detailed in the earthing standards EDS 06-0016 and EDS 06-0017 respectively.

The earthing system for all LV way and ACB fed supplies shall be TN-S (refer to EDS 06-0016).

An end-of-main earth shall be provided at all three-phase cut-outs above (but not including) 100A.

14.5 Metallic Framework Buildings

A metallic framework may consist of:

Steel frame construction.

Continuous metal service (waste or supply) pipes within a property.

Communal metal ducting, such as steel ducts.

Reinforced concrete constructions, where the rebar is exposed or bonded to.

External metal cladding.

Earth bonding between properties.


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This list above gives an indication of the issues involved when identifying a building with common framework.

A new metallic framework building shall only be supplied at LV using the approved designs from Sections 6 to 10. EDS 08-2101 and EDS 08-2102 shall not be used for supplies to metallic framework buildings.

A new metallic framework building requiring a single supply from Sections 6 and 7 shall be provided with a PME supply in accordance with EDS 06-0017 where feasible.

A new metallic framework building requiring multiple supplies from Sections 6 and 7 shall adhere to Section 14.9.

For additional supplies for an existing building of shared metallic framework or shared metallic services from Sections 6 and 7 refer to Section 14.9.


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14.6 Fuse Downgrades

The introduction of smart metering has introduced a new requirement for customers supplied by heavy duty cut-outs.

Smart metering at the time of publication requires whole current metering and cannot be offered from a CT metered supply; therefore customers are requesting a downgrade of supply fusing to enable whole current metering.

This is particularly observed where a commercial customer has inherited a property with a 200A cut-out though has an MPR of less than 69kVA.

If the customer acknowledges that a move to smart metering will limit their MPR requirement to 69kVA, 100A fuses are available for 200A heavy duty cut-outs; refer to EDS 05-4001 for the appropriate fuses.

The 200A cut-out must be able to accept the appropriate meter tails.

Fuse downgrades are not available for 400A to 1440A supplies.

14.7 Metering

The application of whole current or CT metering is an essential element of the Gas and Electricity (Internal Markets) Regulations 2011. The following sub-sections are an attempt to address each scenario that has arisen in the application of these new regulations.

Where all exit points within a building network are equipped with full settlements metering issued from UK Power Networks MPANs, a CT chamber shall not be installed nor any integral CTs connected.

Where some but not all exit points within a building network are equipped with full settlements metering issued from UK Power Networks MPANs, a CT chamber shall be installed or integral CTs connected as appropriate.

Where the development is of a speculative nature or the final arrangements for a building network are not finalised then a CT chamber shall be installed or integral CTs connected as appropriate at the intake by UK Power Networks. It is acceptable for a CT chamber or integral CTs to remain connected when all exit points of a building network have received metering and the boundary metering function is no longer required.

Metering CTs, CT chambers or provisions for whole current meters within a building network shall not be installed or owned by UK Power Networks. Refer to EDS 08-1103.

In relation to a connection to a licensed distribution system, i.e. IDNO Inset Network, the intake connection shall not be metered and therefore no metering CT connection or metering CT chamber is required. Refer to EDS 08-0113.


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Where metering of the intake is required the customer shall provide:

Accommodation for a metering termination box to be located no further than 20m from the CT position.

The metering accommodation shall be weather protected and be provided with adequate light.

The accommodation shall allow the metering termination box to be mounted at a height of between 1m and 1.8m, with a free working space of not less than 1m.

A duct for the multicore cable from the CT position to the meter box.

An external meter cabinet of a type approved by UK Power Networks.

UK Power Networks shall provide and install a 12 or 19 multicore armoured cable which shall be installed within the provided duct.

Duplicate metering CT ratio name plates are provided by the supplier of the CT chamber/integral CTs. These CT ratio name plates shall be fitted inside the metering termination box when this is installed.

14.8 MPANs

MPANs shall be registered by:

UK Power Networks where the building network is owned by an unlicensed BNO.

The BNO where building network is owned by a licensed BNO.

14.9 Service Intake Location and Requirements

14.9.1 Domestic Installations

It is not intended for supplies covered within this standard to be provided to domestic properties, however where these supplies are required for domestic properties:

100A TPN supplies covered in Section 6 shall be externally mounted within an approved three-phase meter box (refer to EAS 13-0000) or free-standing kiosk.

200A and above TPN supplies, shall be mounted at an external supply position in an approved free standing kiosk.

Refer to EDS 08-2110 for additional guidance on physical dimensions and arrangement.

14.9.2 Non-domestic Installations (including Multi-occupied)

For supplies covered in Sections 6 and 7, the proposed location of the service intake position shall be agreed at the design stage and approved by UK Power Networks.

The location of the intake position shall ensure continuous and unrestricted access for UK Power Networks staff. Every opportunity shall be taken to ensure that the intake service position can be accessed independently from the main building.

A building shall have a single intake position per block; multiple intake positions shall not be used for any LV supplies within a single block and each block may not supply another block. A supply from Sections 6 and 7 may have multiple services within the single intake position provided that:


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Any protective earth and neutral bonding shall not exceed 5m in length

Each intake includes appropriate labelling to ensure an operative can easily identify all supplies in an emergency.

Each intake is installed with the appropriate, identical method of earthing, including bonding where necessary (refer to EDS 06-0017).

All intakes are installed and suitably protected to preclude any possibility of parallels across UK Power Networks’ network, to prevent the passage of fault current through a customer’s equipment, overload of incoming supplies, and the inadvertent electrification of a network deemed to be isolated.

For additional supplies for segregated networks within an existing building of shared metallic framework or shared metallic services refer to Section 14.5.

The intake position shall not be located in inappropriate or insecure locations without the installation of segregation or safeguards, for example:

In an area which constitutes a hostile environment e.g. where steam, water vapour or chemical fumes are present.

In an area where it may be subjected to mechanical damage i.e. behind a door which when opened could strike the unit, in an open area where vehicular access/use of mobile equipment could cause damage by impact. It is particularly important for a free standing supply intake position (building, cubicle or cupboard) that it is located in a safe and secure location inaccessible to impact from vehicles.

Directly beneath, within, or immediately adjacent to the bottom of a vertical service duct containing a water pipe where a leak could result in water ingress to the electrical equipment.

In a location with insufficient headroom, clear access and egress or working space where there is a risk of personal injury.

In a location that may be particularly susceptible to fire damage e.g. a communal bin store or public area.

Refer to EDS 08-2110 for additional information.

The intake position shall be segregated from the gas and water pipes, with a minimum separation of 0.5m and shall not be installed adjacent to a gas intake/regulator nor water pipes.

As a result of these conditions it is extremely unlikely that a basement intake room will be acceptable for a new development, therefore every effort shall be made at the design stage to allocate sufficient space for a UK Power Networks service position at ground level. Mitigating circumstances shall be considered by UK Power Networks on a case by case basis.

Where an internal service position is unavoidable the incoming cable route shall be designed to give the shortest possible length of incoming cable inside the building. The service shall be located on or as close as possible to an outside wall nearest to the direction of cable entry into the building.

The customer or developer will be required to provide sufficient space and lighting to accommodate the service and metering equipment as shown in EDS 08-2110. A minimum of 1m clear space in front of the metering equipment door is required. As an alternative the use of an brick built kiosk, approved GRP kiosk (refer to EAS 07-0003) or the approved three-phase meter box (for 100A TPN, Section 6 only, refer to EAS 13-0000). Refer to EDS 08-2110 for additional guidance on physical dimensions and arrangement.


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14.10 Fire Fighting Supply Arrangements

UK Power Networks is unable to provide firefighting supplies that comply with the requirements of BS 9999:2008.

Should a customer require an additional supply as part of the design, this shall be offered in line with the guidance in sections 6 and 7. Please note that additional supplies must be matched; a secondary supply must be of the same size as the primary supply.

14.11 Switchroom Security

Where a dedicated electrical switch room, cubicle or cupboard is provided, a dual locking facility shall be provided. Where the security risk is high the customer or BNO may, by agreement with UK Power Networks, deem it necessary to provide a more secure arrangement, retaining control and responsibility to enable quick entry to the Supply Intake in an emergency. A high security arrangement shall be recognised within the site responsibility schedule and specifically listed in the connection agreement.

14.12 Load Growth considerations

For LV connections covered in Section 8 where anticipated load growth is greater than 550kVA the customer shall be advised to consider other supply arrangements, for example the ACB option or an HV supply.

14.13 Disturbing Loads

UK Power Networks, ICPs and the customer shall refer to EDS 08-1901 for the consideration of disturbing loads.

14.14 Power Factor

Unless otherwise agreed the customer shall ensure that the import and export power factor is maintained between 0.95 lagging and unity.


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14.15 Generator Connections

14.15.1 General

In addition to the provisions of this standard, connections involving generation shall also comply with ENA EREC G99 with particular consideration given toward the earthing provision.

14.15.2 LV Generation for Parallel Operation Only

Earthing for an LV generator designed for parallel operation only shall be installed in accordance with ENA EREC G99 noting that independent neutral earthing for the generator is not a requirement where there is no application for standby generation. A typical arrangement is shown in Figure 14-1.

L

N

E

DNO Supply

and Equipment

Metering Equipment

Customer Isolation

Generator and Isolation

Customer LoadEarth link not for

TT earthing

Customer Earth Terminal

Customer Earth Provision

Figure 14-1 – LV Generator Earthing for Parallel Operation Only


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14.15.3 LV Generation for Parallel and Standby Operation

Earthing for an LV generator designed for both parallel and standby operation shall be installed in accordance with G99. A typical arrangement is shown in Figure 14-2 and Figure 14-3.

Interlocking shall comply with EDS 05-0002.


L

N

E

DNO Supply

and Equipment

Metering Equipment

Customer Isolation

Customer Secondary LoadEarth link not for

TT earthing



Customer TP&N Isolation

Customer Primary Load

Interlocking

Figure 14-2 – LV Generator Earthing for Standby Operation


L

N

E

DNO Supply

and Equipment

Metering Equipment

Customer Isolation


TT earthing



Customer TP&N Isolation


Interlocking

Figure 14-3 – LV Generator Earthing for Parallel Operation


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14.15.4 LV Generation Standby Operation Only

Earthing for an LV generator designed for standby (or independent operation) shall be installed in accordance with G99. A typical arrangement is shown in Figure 14-4 and Figure 14-5.


L

N

E

DNO Supply

and Equipment

Metering Equipment

Customer Isolation


TT earthing



Customer TP&N Changeover


Figure 14-4 - LV Generator Earthing for Standby Operation Only – Mains Supply


L

N

E

DNO Supply

and Equipment

Metering Equipment

Customer Isolation


TT earthing



Customer TP&N Changeover


Figure 14-5 - LV Generator Earthing for Standby Operation Only – Generator Supply

Note: The disconnection of the generator star point from earth is not a requirement for short term parallel

generators.


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14.16 Increased Security of Supply Arrangements

LV networks are not monitored for continuity of supply and are subject to alteration without notice; it is therefore generally not possible to provide LV supplies with additional security arrangements.

Supplies within the CHLDZ may be less prone to fault outage than other LV networks; however the customer cannot be given a guarantee of supply availability from such networks.

Multiple LV supplies shall not be installed at the request of a customer to provide additional security of supply.

A supply with an agreed increase of security can only be provided from supply voltages of HV and above, as detailed in EDS 08-3100 for HV and EDS 08-4100 for EHV.

14.17 Approved Equipment and Materials

All equipment and materials shall be approved by UK Power Networks, as detailed in the following equipment approval standards:

EAS 02-0000 Cables and Joints

EAS 07-0000 Substations and Service Designs

EAS 13-0000 LV Plant and Metering Equipment

14.18 Legal Requirements

All necessary consents relating to the substation, switchroom, cables and access arrangements shall be provided by the customer. If the substation or switchroom is to provide a strategic purpose additional to the function of a supply point for the large LV supply customer, UK Power Networks shall ensure that its interests are adequately protected by the agreed tenancy arrangements.

The rights for the cable route from the point of connection on the UK Power Networks distribution network to the boundary equipment shall be obtained by UK Power Networks or by the customer/IDNO on behalf of UK Power Networks, as these circuits form part of its network.

Necessary land rights shall be secured before starting construction as detailed in EDS 07-3101.


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14.19 Commissioning and Energisation

14.19.1 Single Customers or Building Networks with Partial Settlement Metering

The customer shall appoint an energy supplier and a meter operator before the supply can be energised.

In accordance with ESQCR the following shall be provided before testing and energisation of the incoming supply by UK Power Networks up to the first point of isolation:

A formal confirmation of work completed including customer tails/cables.

A request for energisation in writing together with a statement of testing/compliance with BS7671 (and any other applicable legislation) for the building network, signed by an appropriately authorised person.

A point of isolation on the customers’ network, which shall be secured in an ‘open’ position.


These tests shall include tests for continuity, insulation, polarity and earth fault loop impedance values.

Failure to comply with the above requirements may prevent connection and energisation. Energisation beyond the first point of isolation on the customers’ network is not the responsibility of UK Power Networks.

A ‘Notification of Energised Apparatus Certificate’ shall be issued to the customer or site manager responsible for works on the site, as detailed in HSS 40 052.

14.19.2 Building Networks with Full Settlements Metering

Where the customer network is not settlements metered at the intake connection, the customer network shall be commissioned with the liaison of UK Power Networks or its chosen contractor so that the following aspects are addressed:

Securing and sealing, where required, of all circuitry and exit points of connections to reasonably prevent interference and illegal abstraction of electricity.

Application of MPAN labels at the intake connection and on the relevant exit points of connection within the private network.

Ensure that no exit points exist or are made at the time of commissioning for which MPANs are intended to be registered that haven’t had MPANs registered. In the scenario of Full Settlements all exit points should have an MPAN generated and no exit points should exist for which an MPAN has not been registered.


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15 Disconnections

This section refers to the removal of service cables and associated equipment. In all instances of permanent disconnection, the appropriate LV mains record shall be updated with the alteration.

Refer to HSS 40 052 for additional information.

15.1 100A to 400A Supplies

A temporary de-energisation may be provided for customers supplied by a UK Power Networks owned service cable and cut-out by the removal of fuses at the cut-out where no service alteration or work in the vicinity of the service equipment is required. This may be undertaken by either UK Power Networks or the electricity supplier appointed meter operator.

If temporary de-energisation by fuse removal is insufficient and the customer has requested a permanent disconnection, UK Power Networks shall:

Disconnect the UK Power Networks owned service cable, by pot ending in public land and, if possible, removing the dead section from any private land.

Remove the UK Power Networks owned cut-out, CT chamber and multi-core cable (if present).

Note: UK Power Networks staff shall not undertake the relocation or removal of any supplier or customer owned

metering equipment.

If the pot ended and live service cable is within 2m of the LV main and it is safe and practical to strap the service cable to the main without damaging the service joint, the LV main shall be exposed and the pot ended service cable shall be strapped to the mains cable with cable ties.

If the remaining service cable is greater than 2m from the LV main, a risk assessment shall be undertaken to assess if full exposure of the service cable will not impact the public highway or to assess if another approved means of tracing the service cable is available.

In the rare event that that the original service joint cannot be located or it is impractical to expose the service joint (for example it is obstructed by other services or encased in concrete) the existing service shall be cut and pot ended as near as possible to the mains cable and the position of this pot end marked and identified on the LV mains record.

15.2 400A to 2165A TPN Supplies

Temporary de-energisation for TMFC or LV board customer terminated customer owned cables requires fuse removal within a UK Power Networks substation. These temporary de-energisation shall be discussed with UK Power Networks and resolved on a case by case basis.

If permanent disconnection is required, customer owned cables shall be removed from the UK Power Networks substation by UK Power Networks and, once the cables are in a safe operational area, removed from the site by the customer under supervision of UK Power Networks.

Where disconnection also requires the removal of integral substations, the HV distribution network shall remain compliant with EDS 08-3000.


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16 References

16.1 UK Power Networks Standards

EAS 02-0000 Approved Equipment List – Cables and Joints

EAS 07-0000 Approved Equipment List - Substation

EAS 07-0003 Approved Glass Fibre (GRP) Housing

EAS 07-0021 Signs and Labels for Operational Sites & Equipment

EAS 13-0000 Approved Equipment List - LV Plant and Metering

ECS 02-0019 Cable Installation LV to 132kV

ECS 03-0054 Connection of Large LV Services to Secondary Distribution Substations

EDS 05-0002 Protection and Control Schemes for Customer Demand and Generation Connections

EDS 05-2011 ACB Protection Settings

EDS 05-4001 Fuse Ratings at Distribution Substations

EDS 06-0017 Customer Installation Earthing Design

EDS 07-3101 Pre-Design Requirements for Secondary Substations (internal only)

EDS 07-3102 Secondary Substation Civil Designs

EDS 08-2102 LV Customer Unmetered Supplies

EDS 08-2110 LV Electrical Service Drawings

EDS 08-3000 11(6.6)kV Secondary Network Design

EDS 08-3100 Customer HV Supplies

EDS 08-4100 EHV Customer Demand and Generation Supplies

EDS 08-1901 Guidance for the Connection of Customer's Disturbing Loads

HSS 40 052 Energisation and Disconnection of Electrical Apparatus and Plant Including All Cables

16.2 National and International Standards

BS 7671:2018 Requirements for Electrical Installations (IET Wiring Regulations 18th Edition)

BS 9991 Fire Safety in the Design, Management and use of Residential Buildings Code of Practice 2011

BS 9999 Code of Practice for Fire Safety in the Design, Management and use of Buildings 2008

CDM Regulations Construction Design and Management Regulations 2015

ESQCR Electricity Safety Quality and Continuity Regulations 2002 (as amended)

ENA EREC G99 Recommendations for the Connection of Generating Plant to the Distribution Systems of Licensed Distribution Network Operators

Note: ENA EREC G99 is not mandatory until 27 April 2019. Prior to this it is

recommended that ENA EREC G99 is followed. If this is not feasible compliance with ENA EREC G59/3 shall be accepted for projects commissioned, witnessed and energised before 27 April 2019.


Version: 7.0

Date: 11/12/2018


17 Dependent Documents

This document is referenced in the following documents, any of which may be affected by changes.

EAS 13-0052 LV Equipment for Large LV Services

ECS 03-0054 Connection of LV Large Services to Secondary Distribution Substations

EDS 05-2011 Air Circuit Breaker Protection Settings

EDS 06-0117 Customer LV Installation Earthing Design

EDS 07-3101 Pre-Design Requirements for Secondary Substations

EDS 08-1100 Appendices to ENA ER G81

EDS 08-1101 Inset Networks

EDS 08-1103 Supplies to Multi Occupies Buildings

EDS 08-2000 LV Network Design

EDS 08-2101 LV Customer Supplies up to 100A Single-phase

EDS 08-2108 Supplies to HOT Sites and National Grid Sites

EDS 08-2110 LV Electrical Service Drawings

EDS 08-3000 11/6.6kV Secondary Network Design

CON 05 003b Harmonised Quote Letter

CON 08 114 ICP Fast Track and Approved Designer Scheme

CON 08 116 ICP Self Determination of Point of Connection