scope:

PURPOSE AND SCOPE

This document details the initial commissioning tests for Settlement metering performed in accordance with Technical Guidance Note TGN(E) 56. In instances where the metering differs from the requirements of the TGN, appropriate account of the differences should be taken in determining commissioning requirements. Adequate notice of testing shall be given to enable National Grid Transco (NGT) to witness and authorise tests as it may require.

The tests given in sections E2, E3 and F2 provide the data required to determine the meter compensation requirements within the time constraints set out by BSCP20.

This SCT applies to new installations and to extensions/alterations where parts of the metering (e.g. VT, CT, cabling) are moved or altered. For these latter cases the appropriate sections of the SCT shall be applied.

All the tests and records required by this SCT are identified as Stage 1 Commissioning. (i.e. All tests are carried out isolated from other parts of the National Grid system including in this case the Primary or Measured circuit.)

Some of the information required by this SCT is specifically needed for the Registration of the metering into Settlement.

Where for project reasons it is not possible to measure the VT and CT cable resistances (clauses E2, E3 and F2) at the initial commissioning stage then estimated values using the method described in TGN(E) 56 shall be produced