What is the most common cause of transformer failures?

The most common cause of transformer failures is overloads or shorted loads. When a transformer is subjected to conditions beyond its design specifications, such as excessive load demands, it can lead to overheating. This overheating can degrade the insulation within the transformer, resulting in failures. If a transformer is consistently loaded beyond its capacity, it may not have enough time to cool down, causing the insulating materials to break down and, ultimately, leading to a short circuit or complete failure.

Additionally, shorted loads can create substantial current flow through the transformer that exceeds its capabilities. In such cases, the increased current generates more heat and can quickly cause damage if protective measures, such as circuit breakers or fuses, are not in place or cannot effectively mitigate the surge.

Understanding load characteristics and ensuring that transformers are correctly sized and protected is essential in maintaining their reliability and preventing such failures.