The multi-technology approach to motor diagnostics means you are utilizing different testing technologies that will complement and validate each other. One example is your vibration technician suspects a possible rotor problem in a critical application, but the cost to replace means a shutdown of production, where the motor’s cost is small compared to the incurred costs of the shutdown.
In a situation like this, many people would be reluctant to make the call for replacement, or if the diagnosis is wrong, the cost is very high. Therefore, this motor may be run to failure, due to the uncertainty of the diagnosis. In this case, to put the multi-technology approach in practice, use Electrical Signature Analysis (energized testing) to confirm or rule out the preliminary findings (bad rotor). If the shaft of the installed motor can be turned or the load quickly disconnected, then a Motor Circuit Analysis test (de-energized) can be performed to assess the condition of the rotor, stator, and connections. By utilizing the multi-technology approach you will have more confidence in your findings and hence, a greater degree of certainty that you have determined the real fault(s).
About the Author
Howard PenrosePresident, MotorDoc LLC
Howard is the President of MotorDoc® LLC and the 2018 Chair of SMRP. He has over 35 years of electric motor testing, repair and design experience, starting with a US Navy motor repair job to advanced electric machinery design. Howard is also involved in legislation with the US Government regarding Cyber Security, Infrastructure, Energy, SmartGrid Education and Safety.