Steps for Troubleshooting EMI Levels

Compare the spectrum that generated the alarm with a previous “baseline.”

Contact the plant site (if possible) to determine any changes in plant condition (rain, power level, voltage level, plant modification, etc.) that could have contributed to the increase in EMI.

The plant conditions can help determine if an increase in magnetic or electric fields contribute to the EMI increase. An increase in magnetic fields can lead to more movement of components while an increase in electric fields can indicate a weakness in the insulation structure.

Determine which frequencies have increased over the baselines and the possible plant conditions that could have contributed to the EMI increase. Label these frequencies as “Areas of Interest.”

The Areas of Interest can help determine the subcomponent of the generator or motor that may be causing the EMI increase.

Determine how much the level has increased and whether it is over multiple frequencies ranges or localized in nature. Label these as “Levels of Concern.”