Dynamic rod worth measurement (DRWM) a revolutionary rod worth measurement method

A new method for the measurement of control rod worths, the Dynamic Rod Worth Measurement (DRWM) technique, was developed by Westinghouse to measure rod worths faster and more accurately than existing techniques. The measurements to prove the validity of the technique were performed at a two loop plant. These results indicated that DRWM was easier to perform, more accurate and faster than the rod swap measurement technique being used at the two loop plant. The measured rod worths were obtained in less than two hours. The US Nuclear Regulatory Commission (USNRC) subsequently approved DRWM as a valid technique for measuring rod worths during the startup of nuclear power plants. The author presents the results for the first application of DRWM at four loop plants where DRWM was employed as the measurement of record for the Low Power Physics Test (LPPT) program. For these plants, DRWM was completed in less than two hours and was cited as a major contributor to a record breaking short outage for one of the plants