| Company | American Utility Service |
| Location | USA |
| Timeline | 2018 |
| Project Overview | This case underscores the importance of continuous online monitoring in preventing catastrophic failures |
| Products | Qualitrol Serveron TM8 |
Detecting Transformer Faults with Serveron TM8 – A Timely Intervention
This is a Qualitrol Case Study. See the original article here
Background
In 2016, a U.S. utility deployed the Qualitrol Serveron TM8 monitor on a transmission transformer to ensure continuous diagnostics. For years, the transformer operated without issues. However, on December 19, 2018, the TM8 raised alarms due to a significant rise in acetylene levels, a clear sign of potential hot metal activity. This detection followed an earlier alert about elevated concentrations of ethylene, methane, and hydrogen, suggesting overheating of the oil.
Critical Detection and Response
The TM8 monitor’s automatic switch to an accelerated sampling rate provided high-resolution data, confirming a rapid increase in hot metal gases within just 24 hours. This real-time information enabled the utility to act swiftly. By December 20, 2018, the transformer was taken offline, merely 28 hours after the initial warning.
Root Cause Analysis
A subsequent inspection revealed that a loose nut on the PA Core Leg of Phase 1 had caused localised overheating. The nut's thread damage, likely stemming from insufficient torque during manufacturing, led to its gradual loosening due to operational vibrations. The PA unit was replaced after a thorough inspection to rectify the issue.
Conclusion
This case underscores the importance of continuous online monitoring in preventing catastrophic failures. The Serveron TM8 monitor not only provided early warnings but also enabled a timely and precise response, minimising downtime and repair costs.