Operational Control of the UKPN Low Voltage Distribution Network for EPN and LPN Regions

Operational Control of the UKPN Low Voltage Distribution Network for EPN and LPN Regions Owner Name Title Signature Steve White Head of Network Control and Operations Date 16 February 2016 Authoriser Name Title Signature Adrian Windley LV Control and Dispatch Manager Date 26 January 2016 This document forms part of the UK Power Networks Integrated Management System and compliance with its requirements is mandatory. Departure from these requirements may only be taken with the written approval of the above authoriser. Revision Record Version number 2.0 What has changed? Section 10 planned work requirements. a v5.0 Instruction sheet Date published 18/02/2016 added, Example sheet added for switching operations and Front sheet reformatted and includes LVJ number and contact numbers for LV Control. Next review date 26/01/2017 b v10.0 (now v11.0) and c v3.0 (now v4.0) reviewed no changes. Prepared by Adrian Windley Why has it changed? Requirement to call Control at start of planned work to confirm network is running as expected. Requirement to call Control when making/breaking possible grid parallels a Feedback from operational staff and Subsequent pages to be used by field staff for sequence of switching required Version number 1.2 What has changed? Selected the tick box for circulation to the G81 website. Date published 21/01/2016 Why has it changed? Next review date 17/09/2016 This document needs to be published on G81. Prepared by Clive Everitt Version number 1.1 What has changed? Reference section updated. Date published 17/09/2015 Why has it changed? Next review date 17/09/2016 NOP 73 001a and NOP 73 001b renumbered to b and NOP 50 021c Prepared by N. Ali-Riza Page 1 of 13

Who needs to know? All UK Power Networks Staff Asset Management Capital Programme Connections Contractors Customer Services Finance Legal G81 External website HR & Communications HSS&TT In Business HSS Safety Reps ICPs (Independent Connection Providers) IDNOs (Independent Distribution Network Operators) Information Systems Meter Operators Network Operations EPN LPN SPN Distribution Capital Delivery Logistics Network Control Network Operations Connections Transport Services Strategy and Regulation UK Power Networks Services Airports Rail HS1, DLR & Commercial buildings MUJV / Allenby Business Development Others (specify) Contents 1.0 Introduction and Purpose... 3 2.0 Scope... 3 3.0 Objective... 3 4.0 References... 3 5.0 Definitions... 4 6.0 Responsibilities... 4 7.0 Records... 5 8.0 Process Detail... 5 9.0 Faults... 5 9.1 Fault Switching... 6 10.0 Planned Work on Radial networks... 8 11.0 Planned Work on interconnected networks... 10 12.0 Live Jointing by Independent Connection Providers (ICPs)... 10 13.0 Newly Commissioned / Decommissioned Plant and / or Cable... 11 14.0 Information required for fault reporting purposes... 11 15.0 LV Control Contact Details... 13 EPN LV Control... 13 E-mail address for bookings- EPN LV Control (epnlvcontrol@ukpowernetworks.co.uk) 13 LPN LV Control... 13 Page 2 of 13

1.0 Introduction and Purpose LV Control is established to operate in parallel with the HV and EHV Control functions where the following procedures will apply to operations on the LV network. This procedure replaces NOP 73 001 and NOP 63 001 which have been withdrawn. 2.0 Scope This document covers the control of the LV distribution network within the EPN and LPN Regions and covers both planned and fault work. The primary function of LV Control is to provide guidance and instructions to field operatives working on the LV Network when a fault occurs. The co-ordination of operations on the LV network for fault restoration work and ensure no planned or ICP works clash To manage routine operations and running arrangements on the London Interconnected network. The accurate completion and audits of Fault reports and planned interruption reports ensuring full Rig compliance. Maintain an LV operational diagram showing the current running arrangements with annotations covering known and suspected faults and any abnormalities or defects. 3.0 Objective This document defines the responsibility and procedure for operating on the LV distribution system for Real-time Fault Management and Planned Work in each Region. 4.0 References COP 01 001 COP 01 006 NOP 50 002 NOP 50 018 NOP 72 001 a b c NOP 73 002 EGS 01 004 CON 00 027 Fault Management Process System Alteration Notice Procedure Repeat Supply Interruptions Pre-Arranged Interruption Procedure LPN LV Network Sweeps Procedure LV Switching Operations Schedule Whereabouts Shutdown and Fusing Sheet ICP Live LV Jointing Form Ultra-High Speed Safety Fuses for Excavation Repair Work on the LV Network Electricity Guaranteed Standard 4 (Regulation 12) Notice of Planned supply interruption ICP Jointing to Existing Mains Standard Page 3 of 13

NOC 04 006 HSS 40 017 HSS 40 017a Independent Connections Provider (ICP) Linking and Fusing Service Enquiry Procedure Low Voltage Re-energising devices Low Voltage Re-energising devices LV Ops handbook Regulatory Instructions and Guidance (RIGs) 5.0 Definitions For the purpose of defining control responsibilities with respect to the boundary between LV and HV/EHV networks, LV control shall have jurisdiction over operations on all equipment connected to the LV network beyond, but not including, the LV Transformer Links or Service ACB s. Control of PC400 s will have a shared responsibility between LV and HV Control. For LV PC400 Fuse operations LV Control has the authority to instruct replacement and for isolation for work on the LV network. For isolation of PC400 s for work on the HV network HV Control will instruct and receive confirmation of operations 6.0 Responsibilities LV Control Engineer Maintain an LV operational diagram showing the normal running arrangements with annotations covering known and suspected faults and any planned work where fusing and linking on the network is to remain for longer than 24 hours. The co-ordination of operations on the LV network for fault restoration work and ensure no planned or ICP works clash. The LV Control Engineer will give consent to Authorised operators to switch and link on the network following notification of a fault, these sources can include; o Customer calls advising of no supply or supply voltage variations. o Staff working on site identifying a fault on the network. o Alarm received from the Bidoyng System. o Alarm received from the LV Fuse Monitoring Equipment. o Alarm received from LV Remote Control and Automation System. The accurate completion of Fault Reports and Pre-arranged Interruption (PAI) Reports in line with current RIG guidelines. Provide guidance and assistance to field staff if the network is found to be running abnormally and provide any information that may affect restoration or repair such as reports of cable damage For checking the network running conditions when an ICP Live LV Jointing Form (c) is received, and confirming to the ICP whether their work can proceed. The authorisation of switching schedules for PAIs in any Interconnected network only Page 4 of 13

Field Engineer For all planned work that requires linking and fusing, it is the responsibility of the relevant supervisor to ensure a LV linking and fusing schedule is emailed to LV control for reference if required. LV Control are not required to authorise the schedule All linking and fusing operations should be prepared with reference to the live operational diagram. The relevant supervisor will be responsible for establishing that network loading and security is not placed at risk. Staff who are organising pre-arranged interruption jobs are responsible for completing the necessary documentation, and providing adequate notice of planned works to the Control Centre. All documentation as detailed in NOP 50 018 will be provided via email to the Control Support team at Fore Hamlet. 7.0 Records All records will be held electronically in the Trouble Fault Management system and Fault Reporting system and linking and fusing schedules held in the email system for a minimum of 2 years. 8.0 Process Detail Work on the LV network falls into two broad categories; 9.0 Faults Faults (this includes failure of LV apparatus, overhead lines, cables and third party damage). Planned Work. Unplanned operations shall only be carried out by an Appropriately Authorised Person and with the consent of the appropriate LV Control Engineer as detailed below, except: a) In an emergency to avoid Danger, when an Operator may make a circuit dead without prior consent of an LV Control Engineer. Such action and the circumstances giving rise to the need shall be reported to the LV Control Engineer immediately afterwards. b) Under fault switching where an Operator may replace a fuse once as detailed in section 9.1 The LV Control Engineer Instructs Operations. The LV Control Engineer records the general purpose of the Operations and the Unscheduled Switching number in the appropriate incident log. The LV Control Engineer then instructs the Operator to carry out the Operations and agrees at what stage progress shall be reported. The Operator repeats back the instructions. The Operator records the time that each Operation is complete and informs the LV Control Engineer who records the Restoration Times and dresses the LV Operational Diagram accordingly. Page 5 of 13

The LV Control Engineer Nominates an LV Site Controller. The LV Site Controller is an Appropriately Authorised Person nominated by the LV Control Engineer to control an agreed section of the LV System. The LV Site Controller is given permission to carry out unspecified Operations on a defined section of the LV network. The LV Control Engineer records the general purpose of the Operations which are to be carried out, e.g. back feed substation, repair LV fault etc., the agreed extent and boundaries of the network under LV Site Control and the Unscheduled Switching schedule number. A statement shall be made on whether permission is granted to operate at open points at the boundaries, e.g. LV network from High St Substation up to and including NOPs. The LV Control Engineer and LV Site Controller shall agree at what stage progress shall be reported. The LV Site Controller records each Operation and the time of completion on an Unscheduled Switching Log. At the agreed stage, the LV Control Engineer shall be advised of the LV network running conditions and shall dress the LV operational diagram accordingly. Upon completion of the work, LV site control will be relinquished and control of the network formally handed back to LV Control. 9.1 Fault Switching Where a fuse operation has occurred at a substation or pole mounted transformer and there has been no report of possible damage to the network reported, the following procedures shall apply. The field operative attending will be informed of any report of possible damage relating to the network as soon as it is available. In the following procedures, the use of an approved Fault Re-energising device (HSS 40 017) should be used prior to replacing a fuse to energise a section of network which may have a fault. Alternatively, a Potential Current Indicator may be used to determine if the feeder is likely to be faulty. Consent for restoration Consent is given for the field operative to carry out the required network checks and attempt restoration from either the substation feed or link-box if no fuses have operated at source, except where: The LV Control Engineer revokes consent by either adding comments to the incident log prior to staff being dispatched or via a telephone call thereafter. The LV Control Engineer will note within the incident log why consent is not given and where appropriate add; Any known abnormalities in running conditions Any known restrictions (i.e. inoperable link-box) Any reports of damage received Overhead Services from Pole-Mounted Transformers Trace route of service to check for abnormalities. Replace fuse if route is found to be clear. Contact LV Control Engineer to confirm state of network. Page 6 of 13

Overhead Mains Trace route of overhead main including services from Supply point to the NOP(s) to check for abnormalities. Where underground services are connected to overhead mains it is acceptable to check the route for the presence of excavations. Replace fuse if route is found to be clear. Contact LV Control Engineer to confirm state of network. Mixed Overhead and Underground Mains Trace route of the overhead line from Supply point to the NOP(s) to check for abnormalities. Walk route of cable from Supply point to the NOP(s) to check for 3 rd parties working or any evidence of possible damage If clear, apply an approved Fault re-energising device. If successful replace fuse. Contact LV Control Engineer to confirm restoration or discuss further operations on the network to enable supply restoration. Underground Mains Walk route of cable from Supply point to the NOP(s) to check for 3 rd parties working or any evidence of possible damage. If clear, apply an approved Fault re-energising device. If successful replace fuse. Contact LV Control Engineer to confirm the time of restoration or discuss what actions are required to enable supply restoration. The LV Control Engineer shall discuss the incident details with the field staff and shall instruct the field staff to carry out any further network alterations to maintain or restore supplies: Note: 1. Investigate on site what protection has operated and the extent of any supply failure. 2. Isolate any faulty section of LV network that cannot be restored to service. 3. Restore to service all sections of healthy LV network including operations at Normal Open Points on agreed boundary edge. 4. Report back and update the LV Control Engineer then agree a repair strategy. In the event of loss of supply and there is no access to the feeding substation and testing proves all three phases are dead on the LV network, no attempt must be made to restore the network from a NOP to the LV termination until it can be proven that the HV network will not be energised from a back-feed. If access is not available to test at the substation the LV cable(s) must be split at the first link box or pillar leaving the first leg(s) isolated allowing the remainder of the network to be restored. If there is another circuit to a Normal Open Point (NOP) from the same feeding substation tests should be made to check if there is continuity of supply thus confirming whether the substation s HV supply has been lost or not. If the supply is healthy then the integrity of the HV supply has been proven; therefore the dead LV circuit can be tested using an approved re-energising device. If there is no access to the local substation and at least 1 phase is found healthy at the circuits NOP or the first link-box/pillar from source then the integrity of the HV supply has been proven; therefore the LV circuit can be tested using an approved re-energising device. Page 7 of 13

Generators When connecting a generator to a single premise or LV main (including LV Bus bars if the TX links have been removed) no authorisation is required from LV Control. Once connected the LV Control Engineer needs to be informed of the time the generator(s) were started and supplies restored. When removing a generator from a single premise or LV main (including LV Bus bars where the TX links have been removed) no authorisation is required from LV Control. Once the generator is dis-connected the LV Control Engineer needs to be informed of the time the generator(s) were disconnected and at what time the customers were put back onto normal supply. If a generator needs to be synchronised to the live LV network authorisation must be gained from the LV Control Engineer prior to any works taking place. Use of Ultra High Speed Safety Fuses The application of UHS Safety Fuses must be in accordance with NOP 73-002. To reduce the risk of injury to UK Power Networks staff and contractors whilst excavating or working in the vicinity of faulted or defective low voltage electricity cables and plant Ultra High Speed Safety Fuses may be temporarily inserted during the course of fault location, excavation and repair. Emergency isolations For all fault repair work on the LV network when a section of LV network needs to be made dead and more than 50 customers will be affected, the LV Control Engineer will contact the Supply Restoration Manager (SRM) or Dispatch Shift Manager (DSM) in their absence before giving consent to make the network dead unless there is immediate danger to the public in which case contact with the SRM or DSM will be made after the network has been made dead. It is essential that the network is always sectionalised to only isolate the minimum amount of customers necessary to carry out repairs in a safe manner. 10.0 Planned Work on Radial networks There are two types of planned work on the LV network; Outages that affect customer supplies, Work that involves linking and fusing on the LV network to maintain supplies. For all planned work, a copy of the LV switching schedule (a) shall be completed and sent by e-mail to the respective LV Control Team prior to the work taking place, with at least two working days notice. For any work that permanently changes the network running arrangement a System Alteration Notice (SAN) will be submitted to Network Records to permanently amend the LV operational diagram. The email addresses for each network are as listed in last section of this document. The use of email enables electronic filing of requests to be achieved. If customers supplies will be affected by a planned job, a Pre-Arranged Interruption (PAI) request form will be submitted to the Control Support team in line with NOP 50 018. A Work Proposed (WP) dressing pin will be placed on the LV diagram by the LV Control Engineer on receipt of schedule or PAI request to indicate that a planned job is proposed. If Page 8 of 13

more than one secondary site is being affected by the works then the LV Control Engineer will place a WP dressing pin on all sites involved. The WP dressing will contain; The reference number for the planned work (WP job). Name of the person in charge of the job and a contact phone number. Proposed date of work and the interruption times if applicable. The person in charge of the job will be notified of the LVJ number which indicates the work can go ahead When the WP pin has been placed on the diagram an automated text message will be sent to the person who submitted the booking confirming the LVJ number, planned date, Location and short description of work being carried out. The WP pin will be activated and changed to a Work In Progress (WIP) pin once it has been confirmed that work has commenced. Once work has commenced and changed to WIP an automated text message will be sent to the person who submitted the booking confirming planned work has commenced. A daily planned works list will be produced for LV Control to use as a whereabouts for all planned works scheduled for that day. For jobs which are completed on the same day, the operational diagram will not be dressed to show the LV linking and fusing. On the day of the proposed work, a call will be made to LV Control to confirm the running conditions are as expected prior to commencing with work. A second call will be made on completion of the work and a message left to confirm what time the work has finished, and that the network has been restored to normal. The message must include the person s name, contact details of person on site, the LVJ number and the PAI incident number (if applicable). Once it has been confirmed work is complete and the network has been restored to normal the WIP pin will be closed and an automated text message will be sent to the person who submitted the schedule confirming works are complete. Where there is a possibility of making/breaking open points across a grid parallel during any switching schedule then a call must be made to LV Control prior to the operation being carried out to enable the running conditions of the HV network to be checked. All known grid parallels have been marked on the LV Diagram with an embargo symbol If no supplies are received once planned works has commenced LV Control must contact the operative on site to inform them to stop work and discuss what operations have taken place. The LV Control Engineer will pin the diagram with the full extent of the planned works and give instruction/authorisation to restore the customers and agree any further works. For all jobs with duration of greater than one day, the appropriately authorised person in charge of the work will contact LV Control to confirm the LV running conditions at the end of each day. The LV Control Engineer will dress the network diagram appropriately. For all LV isolations which form part of an HV job, confirmation of isolation of the LV will be made to the HV Control Engineer who will dress the HV diagram to confirm the isolation of the LV network and any back-feed applied as appropriate. A call to LV Control is not required. For LV PAI jobs affecting customer supplies, LV Control must be informed of the time of isolation and the time customer s supplies were restored. The LV Control Engineer will record these times in the incident and complete the associated PAI fault report. Page 9 of 13

For PAI jobs where the actual restoration time is expected to be beyond the time the customer was notified that supplies would be restored, the person in charge of the PAI will telephone Dispatch as soon as they are aware that the job is running late to confirm the anticipated restoration time. If field staff establish that the network is not running as expected or a fault is discovered whilst carrying out the planned switching then LV Control must be contacted immediately. If supplies are lost unexpectedly supplies must be restored immediately followed by a call to LV Control. For example a set of fuse/links is removed which should not affect supplies but does, replace the fuse/link then contact LV Control to discuss. On completion of any work that permanently alters the LV running arrangement; the LV Control Engineer must be notified who will update the LV operational diagram with temporary Information Pin to show the changes as detailed on the associated SAN. Once the diagram has been updated by Network Records, the LV control engineer will remove the temporary Information Pin. If a PAI job is to be postponed or cancelled prior to the planned start date, Control Support must be notified who will re-date the PAI Troublecall incident or cancel from the system. If it is necessary to cancel a planned job, a call will be made to the LV Control Engineer to confirm cancellation of the work. The LV Control Engineer will complete the WP pin and cancel the incident. If a job is postponed prior to the start date, the WP pin and PAI incident can be re-dated if required. Any PAI job that has gone live cannot be re-dated and will need to be re-submitted and the original PAI incident cancelled. If LV Control are not provided with the information required by the person in charge of the works no further bookings will be processed until the information is received. 11.0 Planned Work on interconnected networks For all planned work on the interconnected network, a copy of the LV switching schedule shall be completed and sent by e-mail to the respective LV Control Team for authorisation prior to the work taking place. Two clear working days notice of any job which involves working, fusing or linking on the LV Interconnected Network must be provided to ensure the Control Engineer has sufficient time to check and authorise. Upon authorisation the Control Engineer will return the switching schedule to the person who has submitted. Following receipt of the approved LV switching schedule the process is the same as indicated in section 10 Planned Work on Radial Networks 12.0 Live Jointing by Independent Connection Providers (ICPs) When Live Jointing by an ICP is to be carried out, the form c, shall be completed and sent by email to Control by the ICP giving a minimum notice period of two working days. The Electrical Network Connection column on the form will not be completed by the ICP. The Control Engineer shall check the running conditions as indicated by the dressing on the LV diagram and inform the ICP of the network running condition. ICPs are permitted to work on Radial Networks with fusing which does not exceed 400Amps or in accordance with CON 03 062 Independent Connections Provider (ICP) Linking and Fusing Service Enquiry (Connections Services) Procedure will be used. In the event that the Control Engineer identifies one of the following situations, where CON 03 062 has not been used then an email shall be sent to the ICP informing them. Page 10 of 13

Issue The proposed jointing is in an Interconnected Area. The proposed jointing is in a Radial Area with fusing in excess of 400 Amps. The proposed jointing is in an Area which requires Operational Checks to be carried out by Network Operations Field Staff. Text of Email This work is planned to be in an Interconnected Area. This procedure may not be used for this network. This work is planned to be in a Radial Area with fusing in excess of 400 Amps. This procedure may not be used for this network. This work is planned to be in an Area which requires Operational Checks to be carried out by Network Operations Field Staff. Please arrange for the checks to be completed and re-submit this request, together with the confirmation that the checks have been completed. On the day of the planned jointing work, the ICP shall contact the Control Engineer by telephone to request confirmation that the LV diagram dressing has not changed in a way that would prevent the works proceeding. If no material change is indicated then work can commence. The ICP will then complete the work. In the event that a material change to running conditions of the network is identified when the Control Engineer checks the LV diagram dressing, then work shall not commence. 13.0 Newly Commissioned / Decommissioned Plant and / or Cable A System Alteration Notice (SAN) must be submitted to Network Records within 24 hours (one-working day) of completion of works affecting the LV network. 14.0 Information required for fault reporting purposes Reason for the loss of supply; Network conditions upon arrival; Substation name / TC Number or F/P / L/B Number where the supplies have been lost from; Feeder way or destination of the LV feeder; Phases affected; Fuse size operated; Fuse size replaced; For O/H line faults the pole number where the incident occurred; Pole number / Tx name where circuit was isolated; Load picked up after supply restored; Times for each stage of restoration with detail of which section was restored; Times for each stage of isolation and details of which circuit was isolated; For open circuit faults the number of phases affected and details of where the open circuit is, i.e. first customer affected etc.; Page 11 of 13

Where a generator or temp loop is installed, the time the customer(s) were restored and which customers were restored; Where the generator or loop is removed the time of disconnection and reconnection. Page 12 of 13

15.0 LV Control Contact Details EPN LV Control E-mail address for bookings- EPN LV Control (epnlvcontrol@ukpowernetworks.co.uk) LV Control Faults Internal Local rate Bedford/Cambridge 03301591744 779-2608 01473 266608 Borehamwood/Pinner 03301591749 779-2632 01473 266632 Bury/Ipswich 03301591760 779-2682 01473 266682 Chelmsford/Clacton 03301591754 779-2645 01473 266645 Enfield/Harlow 03301591758 779-2676 01473 266676 Harold Hill/Rayleigh 03301591750 779-2662 01473 266662 Kings Lynn 03301591752 779-2639 01473 266639 Hemel/Luton/Stevenage/St Albans 03301591747 779-2622 01473 266622 Broadland 03301591751 779-2637 01473 266637 Peterborough 03301594915 Norwich 03301594917 LV Control Planned Internal Local rate Chelmsford/Clacton 03301591755 779-2652 01473 266652 Bedford/Cambridge 03301591746 779-2615 01473 266615 Enfield/Harlow 03301591759 779-2678 01473 266678 Harold Hill/Rayleigh 03301591757 779-2669 01473 266669 Hemel/Luton/Stevenage/St Albans 03301591756 779-2635 01473 266635 Kings Lynn/ 03301591745 779-2612 01473 266612 Bury/Ipswich 03301591773 779-2649 01473 266649 Broadland 03301591761 779-2688 01473 266688 Borehamwood/Pinner 03301591748 779-2629 01473 266629 Peterborough 03301594916 Norwich 03301594918 LPN LV Control E-mail address for bookings - LV Control (lvcontrol@ukpowernetworks.co.uk) LV Control (General) 03301 591 814 (T/C Access, completed works, non-urgent, etc) LV Control (Planned) 03310 591 813 (Planned Supply Interruptions) LV Faults (North) 03301 591 815 LV Faults (South) 03301 591 818 LV ICP Line 03301 591 817 Page 13 of 13