There are many tools you can use to perform effective condition monitoring
Most notably are Vibration Analysis, Fluid Analysis, Infrared Thermography, Ultrasonic Analysis, Electrical Analysis and Motion Amplification
HECO has lots more information about condition monitoring in Helpful Articles resource and also our blog, Here You Go. Simply go to our Home Page and type in "condition monitoring" in the search field in the middle of the page...where is says, "What are you looking for?"