Section L: Metering

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Section L: Metering

Simple Guide


Section L of the BSC covers:

    1. the requirements for Metering Equipment

    2. the requirements to install, commission, operate and maintain Metering Equipment for measuring Active Energy and Reactive Energy; and

    3. the role of the Technical Assurance Agent (TAA) in relation to Metering Equipment.

Quantities of Active Energy and Reactive Energy Exported or Imported by any Party at a Boundary Point, or flowing between Systems at Systems Connection Points must be measured and recorded through Metering Equipment that complies with the requirements of Section L of the BSC. However there is no requirement to have in place Metering Equipment in respect of any Import relating to an Unmetered Supply.

Broadly speaking, a Metering System is commissioned Metering Equipment installed to measure Imports and Exports of energy at a Site.

Those obligations of a Registrant of a Metering System that are specified in Party Service Line 100 and the Retail Energy Code Metering Operations (REC MO) Schedule (for Supplier Volume Allocation (SVA) Metering Systems) have to be undertaken by a SVA Meter Operator Agent (SVA MOA1). The principal functions of a MOA are to install, commission, test, maintain and rectify faults on Metering Equipment (including associated Communications Equipment). Registrants of Metering Systems are required to have a MOA in place for each of their Metering Systems at all times and are required to ensure that the MOA complies with the requirements of Party Service Line 100 andthe REC MO Schedule (for SVA Metering Systems). The appointment of MOAs is covered in Section J of the BSC.

Metering Equipment

Basic Requirements

Each Registrant of a Metering System is required to ensure that the Metering Equipment is installed, commissioned, maintained and operated in accordance with the requirements of Section L and the applicable Codes of Practice.

The applicable Code of Practice is the version that was in force and applicable to that Metering Equipment at the time that it was first registered for the purposes of Settlement2 . (It should be noted that the transfer of a Metering System from one registration system to another does not constitute a new registration for these purposes and the Metering Equipment is not considered to be a new installation of Metering Equipment.) However where any 'material change' is made to Metering Equipment, the relevant Code of Practice is the version applicable at the time that the material change occurred.

Different types of Metering Equipment are installed depending on the purpose in Settlements. Half Hourly Metering Equipment must be installed for Central Volume Allocation (CVA) Metering Systems, SVA Metering Systems at 100kW Metering Systems and SVA Metering Systems associated with any Third Party Generating Plant (except in the case of 'Small Scale Third Party Generating Plant'3 ). SVA Metering Systems in Profile Classes 5 to 8 with advanced Meters installed must be settled as Half Hourly Metering Systems by 1 April 2017. The Change of Measurement Class process for these Metering Systems will be phased from 3 August 2015. For other SVA Metering Systems the Registrant can choose whether to install Half Hourly or Non-Half Hourly Metering Equipment.

For new CVA Metering Systems, as well as installing and commissioning the Metering Equipment, a proving test (as specified in BSCP02) must be successfully completed before the registration of that Metering System can become effective and (as per the rules in Section K) the relevant connection will not be energised until (amongst other things) the Metering Equipment has been installed and commissioned.

For new SVA Metering Systems the Registrant must use all reasonable endeavours to ensure that the Metering Equipment is installed and commissioned before the registration of the Metering System becomes effective. If the Registrant of a new SVA Half-Hourly Metering System (that is at 100kW Metering Systems Premises4 or associated with Third Party Generating Plant) fails to ensure that the Metering Equipment is installed and commissioned prior to the Metering System registration becoming effective, he will be liable for a charge (details of which can be found in Section S, Annex S-1 of the BSC).

Where the same Metering Equipment at an Exemptable Generating Plant is comprised of both a SVA Metering System and a CVA Metering System, the Registrant of each Metering System will provide to Elexon details of such Metering Systems. Elexon will maintain a record of such Metering Systems and the identities of the Registrants. Each Registrant of a Metering System must establish and maintain Meter Technical Details in respect of the Metering Equipment that are true, complete and accurate and provide those Meter Technical Details to the Central Data Collection Agent (CDCA) or Data Collector as appropriate.

Registrants of Metering Systems must also collect and provide certain information and records relating to the Metering Equipment to certain people (including the BSC Auditor and the CDCA). This includes providing records required by the applicable Code of Practice for that Metering Equipment and by the Electricity Act 1989 (the Act). If another Party becomes the Registrant for the Metering System, the details of these records must be passed on to the successor Registrant's MOA. Further details on information requirements are contained in Party Service Line 100 (for CVA Metering Systems) and the REC MO Schedule(for SVA Metering Systems).

Registrants of Metering Systems must let the BSC Auditor have unrestricted access (subject to any operational or safety requirements) to the Metering Equipment and data, information and records kept in relation to that Metering Equipment.

Detailed Requirements

Levels of accuracy are specified for Metering Equipment and are contained in the applicable Code of Practice or in the Electricity Act 1989 (the Act). It is the responsibility of the Registrant of the Metering System to ensure that these levels of accuracy are met. Where the ability of the Registrant to meet such levels of accuracy is dependent upon associated current and voltage transformers that are not owned or controlled by the Registrant, such as a customer for example, then the Registrant must obtain the assistance of the Equipment Owner in meeting these levels of accuracy. If the Equipment Owner is a Party to the BSC, the BSC requires them to provide such assistance. Where current and voltage transformers which are to be used for Settlement purposes are owned by a BSC Party then in respect of the calibration, commissioning and testing of these items of Metering Equipment the Equipment Owner must comply with any requirements in CoP4.

All Metering Equipment must comply with or exceed the requirements set out in the applicable Code of Practice. Where no applicable Code of Practice exists, then the requirements of the Act apply. A Metering Dispensation can relieve any or all of these requirements. A Registrant can apply to the BSC Panel for a Metering Dispensation if, for financial reasons or reasons of practicality, any or all of these requirements will not be met. The Panel will consult with specified Parties in deciding whether to grant a Metering Dispensation. The Panel can also, of its own initiative (and after consultation with Parties), establish Metering Dispensations from the requirements of a Code of Practice. BSCP32 sets out detailed processes covering Metering Dispensations.

Routine testing must be undertaken by the Registrant to confirm the accuracy of Metering Equipment. The minimum frequency for such testing is specified in the applicable Code of Practice (or may be required by statute). In addition where defective or inaccurate Metering Equipment is replaced, the Registrant must commission the replacement Metering Equipment as soon as possible after its installation.

The Registrant must provide Elexon (or the CDCA) with reasonable advance notice of the date, time, location and nature of tests of CVA Metering Systems. The Panel can also request that notice is provided to Elexon for the testing of specified SVA Metering Systems. Elexon is entitled to attend any tests for which it has to be notified.

If the Registrant of a Metering System or any other Party or the CDCA believes that Metering Equipment is not meeting required levels of accuracy or is incorrectly recording data, they must notify Elexon, the Registrant (in the case of another Party or the CDCA) and the relevant Distribution System Operator and/or National Electricity Transmission System Operator (NETSO) as appropriate.

If Elexon is notified or has reason to believe that Metering Equipment is not meeting the required levels of accuracy or is incorrectly recording data, Elexon can require that the Registrant inspects and tests the accuracy of the Metering Equipment and the tests must be carried out in the presence of an Elexon representative. Alternatively Elexon can arrange for the inspection and, if necessary, testing of that Metering Equipment by someone that is suitably qualified in the operation of Metering Equipment.

Metering Equipment must be sealed and secured and it is the responsibility of the Registrant to ensure that this is the case. If Metering Equipment is found to be defective the Registrant must repair or replace the defective component as soon as possible.


Testing of Metering Equipment might be required in order to support a Trading Dispute (Section W) contains the rules covering Trading Disputes). If this is the case, the test will be undertaken on the relevant Metering Equipment in its operational position and, if requested by Elexon, shall be in the presence of a representative of Elexon or (for CVA Metering Equipment) the CDCA. The test will also be in the presence of the relevant Distribution System Operator and/or NETSO as appropriate. The Panel can also decide to allow up to two Parties, nominated by Elexon and representing Parties who have an interest in the Trading Dispute, to witness the test. Section L contains further details on the way in which such tests will be conducted.

Metering Data

The Registrant of the Metering System owns the metering data. The Customer (at any premises) or Third Party Generator in relation to a Metering System at their premises or plant is entitled to access metering data relating to that Metering System without charge.

The Registrant must provide access to and authorises the use of metering data by the Panel, any Panel Committee, Elexon, each BSC Agent and, in the case of an Interconnector, the relevant Interconnector Administrator, Interconnector Error Administrators and Interconnector Users without charge where access is required in order to give effect to the BSC. These data recipients can only release the metering data to another person if the BSC provides for that other person to have access to the data or the BSC explicitly provides for the release of the data or where the Registrant has given his express permission.

In addition the Registrant must provide metering data to each other Party and any other person that is entitled to receive such data under the BSC.

Furthermore the Registrant (or the Supplier Volume Allocation Agent (SVAA) or the CDCA, as specified elsewhere in the BSC) must provide without charge metering data to the relevant Distribution System Operator and NETSO for the purposes of operating their respective systems and the calculation of charges for connection to and use of their systems.

Access to Property

The Registrant of each Metering System must provide rights of access to property upon which Metering Equipment is located and the right to perform tasks (including testing of and reading of Metering Equipment) for any Invitee, the BSC Auditor, the CDCA and the Technical Assurance Agent (TAA) as appropriate, in order that they can undertake activities or exercise rights assigned to them under the BSC. An Invitee is the Panel, any Panel Committee, Elexon, the TAA, the CDCA, the BSC Auditor, NETSO, any CfD Counterparty, any CFD Settlement Services Provider, the CM Settlement Body and/or any CM Settlement Services Provider. If the Registrant is unable to procure such access rights, he must notify the Panel and the Authority.

The Registrant is also required to make arrangements and provisions to ensure that safe access is provided. In doing so, the Registrant can, where reasonable, make arrangements to limit or restrict the rights of access and/or provide direction or regulations to do so, such as: the identification of relevant Metering Equipment; the access routes applicable to the land in question; any limitations on the times that access can be provided; and disclosure of any known hazards on the site.

Such rights of access are free but Elexon must do what it reasonably can to ensure that each Invitee avoids or minimises damage to the property and causes as little disturbance or inconvenience as possible to others at the property. If any damage is caused, Elexon must make good that damage.

Special provisions apply to any area where the owner or occupier is the holder of or is subject to a licence granted under the Nuclear Installations Act 1985 (a 'Nuclear Site Licence').

Technical Assurance of Metering Systems

The TAA monitors compliance by Parties with the requirements of Section L of the BSC, Codes of Practice and BSC Procedures (BSCPs) in relation to Half Hourly Metering Systems, and identifies cases of non-compliance in relation to those Metering Systems. To do this, the TAA carries out on-site Inspection Visits and Desktop Audits of sites where Metering Equipment is installed.

The CDCA and Supplier Meter Registration Agent (SMRA) submit details of registered Half Hourly Metering Systems and the associated Registrants to Elexon. Elexon periodically submits a list of the Metering Systems and the associated Registrants from which sample on-site Inspection Visits and Desktop Audits must be selected. BSCP27 sets down further information in relation to the Technical Assurance of CVA and SVA Metering Systems.

Elexon (consistent with any guidance or instructions from the Panel) tells the TAA the total number of Metering Systems to be audited by each method in a BSC Year, and the criteria for assessing which Metering Systems shall be selected for on-site Inspection Visits and which Metering Systems shall be selected for Desktop Audits. The TAA selects a sample of Metering Systems to be audited in accordance with the requirements of Section L and BSCP27. The sample selected must be consistent with the following principles:

    1. it must allow for targeted audit of a number of Metering Systems where non-compliance is suspected (as notified by Elexon to the TAA on the basis of information provided by other people) and re-audit of a number of Metering Systems where non-compliance was previously identified and has since been reported as rectified;

    2. it must be representative of the Metering Systems respectively registered in Central Meter Registration Service (CMRS) and Supplier Meter Registration Service (SMRS);

    3. it must be representative of MOAs, types of Metering Equipment, Codes of Practice, Registrants, GSP Groups (for SVA Metering Systems) and previous audits and must not be biased towards any one type of Registrant, MOA, GSP Group or type of Metering Equipment.

The TAA provides advance notice to the Registrant whose Metering Systems have been selected for audit. The TAA invites the Registrant or a nominated representative to attend on-site Inspection Visits, and the Registrant ensures that the MOA attends and confirms their attendance to the TAA. The TAA also notifies the Registrant whose Metering Systems are selected for Desktop Audit, giving prior notice as specified in BSCP27. The format and timescales for submission of documentation required for a Desktop Audit are specified in BSCP27.

The TAA will decide that a Metering System is non-compliant if the requirements of the BSC and the relevant Code(s) of Practice are not being adhered to and if configurable Meter parameters are not consistent with the Meter Technical Details supplied by the Registrant. The Registrant of a Metering System can refer question of non-compliance to the Panel if the TAA determines a Metering System to be non-compliant.

In the event of non-compliance, the Registrant must ensure that the Metering System is rectified, following which (if the Metering System was found to be materially non-compliant), Elexon can require the Registrant to carry out the relevant Code of Practice Four tests and validation testing.

The TAA issues notices of compliance or non-compliance following an audit (as per the timetables specified in BSCP27). The TAA submits a monthly report to Elexon summarising all audits failing due within that month and submits the report (as amended by Elexon’s comments on it) to the Performance Assurance Board.

Need more information?

For more information please contact the BSC Service Desk at or call 0370 010 6950.

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1 “MOA” applies to both SVA MOAs and CVA MOAs.

2 In relation to the calibration, testing and commissioning of any Metering Equipment at any time, the relevant Code of Practice is the latest version of the CoP4 which is prevailing at the time.

3 Small Scale Generating Plant comprises distribution connected generating where the aggregate maximum generation capacity does exceed a defined limit.