The performance of demand meters under varying load conditions

The influence of load variations on the performance of four different types of electricity demand meters was studied using a computer controlled test system capable of reproducing load profile data recorded in the field. Results of the tested meters are compared with computer calculated demand values based on readings of a fast response reference multimeter. Differences in readings in the range of -9.3% to +5.3% were observed during the tests of the four demand meters. For the load profiles considered, demand calculations based on one minute subintervals resulted in values closer to the true peak demand than calculations with five minute subintervals