Transformers are critical components in power distribution networks, transferring electrical energy between circuits. Ensuring their optimal performance is vital for maintaining a reliable power supply, and regular servicing of transformers can prevent costly breakdowns and extend their lifespan.
We consider ourselves experts when it comes to our transformer services, and below are the most common signs that indicate your transformer needs servicing.
1. Unusual Noises
Transformers typically emit a low-level hum due to the magnetostriction effect in the core.
However, if this “hum” becomes louder or if you notice unusual buzzing, it could indicate issues such as loose laminations in the core, electrical discharges, or mechanical vibrations. These sounds are often early warning signs of internal faults that require immediate attention to avoid further complications.
2. Overheating
Transformers are designed to operate within specific temperature ranges, but if they begin to overheat, various factors can cause this, including overloading, poor ventilation, or insulation failure.
High-temperature alarms or physical signs of overheating, such as discolouration or burning smells, necessitate prompt servicing to prevent insulation breakdown and potential fire hazards.
3. Increased Energy Consumption
If your energy bills increase without corresponding usage, your transformer might be operating inefficiently and need attention. Issues such as winding short circuits, core saturation, or load imbalances can cause transformers to consume more power. Therefore, it’s advised that you carry out regular transformer efficiency testing and load analysis to identify these problems, allowing for timely servicing.
4. Frequent Tripping
Frequent tripping of circuit breakers or protection relays is a clear indication of underlying electrical faults. These could be caused by issues such as insulation failure, winding faults, or external short circuits. At Johnson & Phillips, we see this quite often, but with continuous monitoring and diagnostics, we can pinpoint the exact cause and undertake necessary transformer repairs and maintenance.
5. Visual Inspection Signs
Regular visual inspections can reveal a lot about the condition of your transformer. Signs such as oil leaks, rust, cracks, or other physical damage are clear signs that something is wrong. Oil leaks, in particular, can lead to a drop in insulation performance and should be addressed immediately.
Below is a photo of a transformer we recently repaired. As you can see, it was clear that it had been overdue for a service for quite some time.
6. Oil Quality Degradation
Transformer oil plays a critical role in insulation and cooling, and over ver time, contaminants such as moisture, acids, and sludge can degrade the oil quality. Therefore, regular oil testing and analysis can reveal the need for oil purification or replacement, ensuring the transformer continues to function efficiently.
7. Age of the Transformer
From our experience, transformers have a finite lifespan, typically ranging from 20 to 30 years, and as they age, the likelihood of faults and failures increases. However, regular assessments of ageing transformers can help determine when it’s time for refurbishment or replacement.
Is It Best To Replace or Refurbish?
Deciding whether to replace or refurbish a transformer depends on several factors, including its age and condition and the specific requirements of your power distribution system.
Refurbishment is often more cost-effective and can extend the transformer’s life, especially if the issues are minor or moderate, such as worn-out insulation, oil degradation, or minor mechanical faults. Refurbishing a transformer involves replacing or repairing components, cleaning, and testing the transformer to restore it to optimal working condition. Of course, the main benefit of refurbing instead of replacing is that it’s quicker and minimises downtime.
Replacement, on the other hand, may be the better option if the transformer is very old, extensively damaged, or if newer technology offers significant advantages in efficiency and reliability. Replacing an outdated transformer can provide improved performance, reduced energy losses, and lower maintenance costs in the long run. It’s also necessary if the load requirements have significantly increased beyond the existing transformer’s capacity.
As a specialist transformer manufacturer, we can offer both replacement and refurbishment of your old transformer. If you are unsure which would be the best option for you, please get in touch with our team.
Conclusion
Regular servicing and maintenance of transformers are essential for ensuring their longevity and reliable performance. The signs we mentioned above are the most common signs our high-voltage engineers come across, but due to the complexities of some transformers, they may provide further telltale signs.
At Johnson & Phillips, we offer a comprehensive range of services tailored to your transformers’ needs. From testing to emergency backup power, our expert team is here to ensure your transformers operate at their best.