The Importance of Temporary Instrumentation in ASME Performance Testing

Due to the economics associated with power generation equipment, accurate data is of paramount importance for the demonstration of thermal performance for the primary power plant components. Since performance measurements and field acceptance tests are also used to base line a plant’s performance, inaccurate data might result in millions in financial loss over a plants life span. Therefore, having low measurement uncertainty associated with test instrumentation is a fundamental requirement. With advancement in (digital) instrumentation and control (I&C) systems for power plants, there has been a growing trend to utilize plant instrumentation in the execution of the American Society of Mechanical Engineers (“ASME”) performance tests. This paper will exhibit the issues with utilizing station instrumentation and provide guidance on the evaluation of these instruments. This paper will also discuss the importance of using instrumentation for the explicit use during testing (“Temporary Instrumentation”) in the conductance of ASME code level testing. Cases will be presented that demonstrate how Temporary Test Instrumentation has identified problems that would have otherwise been overlooked if station instrumentation had been used during thermal performance testing.