Abstract :
After setting out some of the problems of metering, such as choosing the best meter rating for the job. determining the optimum period at which meters are removed for cleaning and recalibration, etc., it is emphasized that, wherever possible, the approach should be on the basis of economics. Since no rational solutions can be found without adequate information about consumers´ load characteristics, including the spread of the actual consumption over the load range of meters, a pilot investigation on operational-research lines has been arranged. Under the aegis of the Utilization Research Committee of the British Electricity Authority and Area Boards, a sample of 110 domestic consumers was drawn from a large urban area, and a novel load-analysing meter and a demand indicator were installed with each of them for a year concurrently. From the data obtained, supplemented by previous E.R.A. work, it is suggested that for installed loads of up to 40 amp, a meter of nearest (but not lower) maximum continuous rating should be chosen, whereas for all higher loads encountered so far, a meter of 40-amp m.c.r. would be sufficient. With the particular meter sizes used in the area concerned, just under 13% of the total consumption was found to have been taken while the individual consumers´ loads did not exceed 10% of the normal ratings of the meters, and only 8% while these ratings were exceeded. Analysis by meter size showed the load sub-ranges in which the highest concentrations of consumption might be expected. From a composite picture of the distribution of consumption at various loads it emerges that as much as one-third of the total annual consumption was taken while the individual consumers´ loads did not exceed 5 amp, and well over one-half while they were below 10 amp, whereas less than one-tenth was taken at loads exceeding 20 amp. These findings apply only to conditions similar to those in the area sampled. It is hoped that many more sample tests will be conducted,- enabling comprehensive load/consumption characteristics to be derived on which to base rational decisions on future meter policy.
