Project Nexus Workgroup

Primes & Subs

7th October 2014

Background

• Action NEX09/03 from 9th September Workgroup:

– To provide an example of how a Class 4 Prime with a Class 3 Sub meter would actually work with regards to reconciliation.

• The next slide provides an example of a Prime with two Subs.

Prime & Sub Reconciliation – Co-Terminus Reads

Prime – any class

Sub 1 – any class

Sub 2 – any class

Read 1

Read 1

Read 2

Read 2

Read 3

Read 3

Read 4

Read 1

Read 4

Read 5

Read 3Read 2

Co-Terminus reads

Sub 1 has been subject to 4 reconciliations over the period, Sub 2, 3 reconciliations and the Prime 1 reconciliation.

Prime & Sub reconciliation

• Sub reconciliation:- Sub reconciliation is at meter point level. Each time a valid read is

received the Sub will be reconciled

• Prime reconciliation- Prime reconciliation requires reads at the same time for the Prime

meter and all its Sub meters (co-terminus reads)- When co-terminus reads are received the Subs can be reconciled

and the Prime can be reconciled (the Prime consumption is calculated, all the Sub consumptions are deducted, what is left is the gas consumed by the appliances fed directly by the Prime).