Verifying Suitability for Service With EMI Diagnostics

This paper provides examples of conditions found with nuclear plant electrical equipment by the application of EMI (electromagnetic interference) Diagnostics. This is an on-line test that can detect a wide variety of defects in motors, generators, power cables transformers and isolated phase bus. There is no interruption to service and no risk to the system while data is collected. Photo 1 shows the temporary placement location of a RFCT (radio frequency current transformer) to collect EMI data from this CWP motor. Photo 2 shows the RFCT application on the generator stator grounding transformer. This is the preferred location to collect generator system data.