Accuracy Key to Testing Meters

Abstract

This article discusses when to replace residential water meters and refers to the 1998 Optimum Meter Age Study. The study indicated that not only the accuracy and performance of meters needs to be tested, but also the accuracy of the testing methods and devices used needs to be measured. It states that the accuracy of positive displacement meters deteriorates over time because of accumulated registration, and disk nutations or piston oscillations in the measuring chamber of the meter create wear and tear that has a negative effect on accuracy and indicated consumption. Criteria for analyzing the method used to bench‐test meters after removal from the distribution system are given, along with criteria for analyzing the test results. The effect of meter change notices left at customers' property when meter changes were performed is discussed, and a graph showing the most cost‐effective time frame for residential meter replacement is given.