Here You Go.


Electric Motor Repair: Observations and Findings


2020-12-Electric motor repair checklistWhen you repair an electric motor, it is critical to organize, observe, and interpret findings properly to make the right decisions about the motor in question. One way to do this is to prepare a set of Observations and Findings based on what was found during the inspection process. Let’s talk about what to expect when reading through this information.

What Are Motor Repair Observations and Findings?

For every motor that comes into our shop, we summarize the repair and test results into observations and findings. This information gives an overview of what we discovered during the testing and inspection process, explains how it relates to issues that the motor had, and also provides potential reasons for the failure so that the client can prevent it from happening again. The test data it’s based on informs the troubleshooting and repair process, and this summary helps the customer make a decision about needed repairs.

Why Not Call it “Cause of Motor Failure”?

In the old days, this used to be called “Cause of Failure” but, when we think about it, is that really what it is? “Observation and Findings” seems to be better terminology for the information contained because we may not know the entire story of what happened to the motor, despite all the data we can gather from inspection and testing. If we want to have a true RCA or (Root Cause Analysis) an investigation is needed - generally more than just looking at the motor itself, which may just be a result of the failure.

How are Observations and Findings Organized?

At HECO, we categorize the observations and findings into four different groups: 

  • Electrical
  • Mechanical
  • Contamination
  • Preventative Maintenance

The electrical category often contains information about motor winding failures. The mechanical category can include issues with bearings, lubrication, or vibration. The contamination category seems rather self-explanatory, but the customer will receive detailed information about the nature of the contamination (water, oil, dust, dirt, carbon) and how it impacted motor performance. Finally, the preventative maintenance category logs items that didn't have actual issues but were sent in for preventative maintenance.

Why are Categories Used?

Categories can help break down the common causes of concern that have the same motor requiring repair or have multiple motors with the same problems. Categorizing issues in this way becomes extremely important when we have customers with a large volume of motors that need inspection and repair

For example, one customer may send in several cooling tower motors with the same issues in the windings or several fan motors that are suffering from severe contamination. This points to a larger problem in the operating environment that the customer may need to address and gives the customer an opportunity to plan for an inspection of similar motors.

What Will I Find in the Observations and Findings?

In the Observations and Findings, the focus will be on the primary issue/cause. There may be several issues discovered that are not related to the main reason the electric motor was sent to our facility for.

Once the primary issue is identified, we provide the customer with a sequence of events that explains how that cause led to a failure. For example, a bearing failure may be the primary cause; when that bearing failed, the rotor began to drag on the stator and eventually damaged the insulation to the point that it grounded the stator. 


At HECO, we find the Observations and Findings section is as important for us as it is for the customer. It allows us to keep track of what is going on with all the motors you send to our facility. From there we can see the forest and the individual trees, allowing us to make recommendations that can have a positive impact on multiple motors in your fleet. And even if you are just sending in a single electric motor for inspection and evaluation, you will receive a summary of what we found in a language you can understand.

Author: Justin Hatfield at 


Subscribe to the HECO blog



Subscribe to Email Updates

Posts by Topic

see all

Recent Posts