3 Telltale Signs Your Cast Resin Power Transformer Is Deteriorating and Needs Prompt Repairs or Restorations

Posted on: 20 December 2021

Electrical power is an inevitable resource that most businesses can't do without when aiming for efficiency and productivity. However, it relies on power transformers that help increase or reduce its voltage or current. A faulty cast resin or dry-type power transformer can impede critical business functions and result in costly downtime. That's why carrying out comprehensive evaluations, regular maintenance, and timely repairs of your dry-type power transformer are essential. 

Knowing the following signs of a faulty dry-type power transformer can help you prepare for repairs or replacement of the unit. 

Unusual Noises From the Unit

One undeniable sign your power transformer is about to fail is the unusual noises coming from the unit. Once you notice this, consider calling in a professional electrician for diagnosis and prompt repairs. Contrasting tones or pitch on the equipment might also indicate imminent failure. Therefore, consider paying more attention to the unit's sounds to learn whether it needs immediate repairs or maintenance. 

Irregular Vibrations of the Unit

When your dry-type power transformer starts vibrating differently, it might indicate a severe problem. Irregular and prolonged vibrations might mean that the unit is gradually failing. Usually, cast resin transformers are fitted with rubber pads on their runners to help reduce resultant vibrations. 

But these pads can wear down over time, ceasing to offer the required cushioning. As a result, this exposes the unit to excessive vibrations that might damage various parts of the transformer. During the maintenance process, assess the rubber pads and, if worn out, have them replaced to guard against potential transformer damage.

Colour Changes on Its Insulation

Another obvious sign that your dry-type power transformer is headed for a breakdown is its insulation's change in colour. This problem will primarily arise from excessive heat emerging from the unit. Continuously operating power transformers will produce heat over an extended period, which causes the colour of the insulation to change. The insulation material might turn darker than its original colour.  

Try assessing the cast resin power transformer's exterior HV insulation windings at the middle or top sections. Generally, the top insulated sections lose their natural colour faster than the lower sections when hot air rises after heating. There is a significant overheating problem if you find some considerable colour difference between the upper and lower parts of the unit's insulation materials. Therefore, you must contact your electrical contractor to service your power transformer immediately.  


Is your dry-type power transformer showing some or all of these signs? If the answer is yes, contact a transformer repair and restoration professional for prompt fixing or replacement of your unit. Doing this will ensure a smooth electrical power supply and uninterrupted business functions. 

Reach out to a professional if you have any questions about power transformers