Today, many companies are adjusting their costs and expenses, and are changing internal policies that help in reducing maintenance tasks and operations in electrical equipment. This obviously brings minimized costs, but only for a short period of time. In fact, this also results in increased risks in the long term because less maintenance means amplified threats. Also, such modifications and reductions result in making such transformers work above their normal load to get the expected performance. And, ultimately this results in making it difficult to obtain maximum profit from their normal work. Therefore, reduction in maintenance operations results in negative impacts like lack of efficiency and premature ageing.
Because of all the above reasons and more, it is advisable that a minimum preventive maintenance program is carried out to detect risky situations so that defined corrective actions can be undertaken. Such maintenance programs when taken up can avoid mid-term breakdowns, electric failures, and non-programmed stops; ultimately avoiding inconveniences in the end customers’ service. A preventive maintenance schedule comprises of regular inspections and component replacements as per the product maintenance schedule. The organic products within transformers degrade over time and ultimately lose the capability to withstand stresses that they might see in their daily usage, like vibration, short circuits, energizing, etc. All of these stresses and faults must be detected as soon as possible to avoid further damage and repairing costs.
In order to choose the most appropriate maintenance program, you first need to know the status and evolution of the transformer. Also, you must make sure to purchase your transformer from a manufacturer that utilizes the best quality raw materials, and standard procedures to construct its transformers. One such name you can rely upon is Miracle Electronics who manufactures power transformers in India that are RoHS Compliant, Reach Compliant, and available with CE and UL marks. Other elements that need to be considered for faults include transformer accessories like isolators, oil cooling pumps, and tap changers.
The most important efforts acting on a power transformer include mechanical efforts, thermal efforts, and dielectric efforts. Similarly, there are various diagnosis techniques used for analyzing power transformer faults. These include –
- Mechanical analysis – excitation current, capacitance, short-circuit impedance, polarity, transformer ratio, frequency response analysis, and winding resistance.
- Thermal analysis – infrared thermographs, dissolved gas chromatography, hydrogen equivalence method, and furanics analysis.
- Dielectric analysis – dielectric rigidity, humidity, isolation resistance, capacity, dielectric frequency response, and ultrasonic method.
Today, it is even more important than ever before to use high qualification measurement equipment that allows making the tests as automatic as possible and having a data base to optimize diagnosis tasks, due to the reduced stop times available. As transformer manufacturers, it is important to carry out tests that are under applicable norms to ensure that the transformer will work perfectly under every environmental condition.
To sum it all up, we can say that it is really important to make preventive maintenance plans to keep active the optimal service conditions, and foresee faults to avoid unexpected high costs.