Reasons for Transformer Failures

Distribution Transformers are being blamed for heavy failures. The Failures are estimated at 20% per year. This amounts to a staggering National loss, considering that Millions of Transformers are installed all over the country. The loss is quite unbearable.

The public suffers because of frequent breakdowns. There are annoying outages in Urban areas. In agriculture area, farmers work suffers. Even industry has suffered huge production cuts. We need to ask why the Transformer fail?

Actually everyone in Discoms knows the answer why Transformers fail! The reasons can be outlined as follows:-

1.Transformers are heavily overloaded
2.Rampant power theft
3.Selection of rating of Transformer is inadequate. Transformer Rating is much lower than what is required.
4.Secondary side protection is bypassed. There are frequent reports of vandalisation and breakage of Meter Protection Box.
5.There are serious earthing problems specially with single phase Transformer.
6.Poor Installation of Transformer, especially improper termination is leading to frequent failures.
7.Usage of transformer being done with unbalanced loads, or unequal load on the Three Phase.

Discoms are unable to obtain political approval for taking stern action against power theft. Discoms are unable to activate civilian support against power theft.

Whilst the failed Transformer can be got rectified against five years warranty from the Manufacturers, the real cause of the problem remains unattended. Hence the actual disease, actual reason why Transformers failed, is neither analyzed nor rectified. Only the symptom i.e. failure of the Transformer, is got rectified under warranty, but the root cause remain and these continue to haunt the Discoms by creating huge AT&C losses.

Consequently Manufacturers are blamed for the failures. They are soft targets. The warranty for Transformers have gone up from one year to two years and to five years. The Manufacturers have been house-trained, or compelled, to work in such a way that they do not question why Transformers have failed. Across the country Manufacturers are repairing Transformers under warranty for 5 years, without questioning cause of failure, but knowing fully well that most failures are occurring for reasons other than manufacturing defect.

It has been established in many studies that there is a DIRECT RELATIONSHIP between FAILURES OF TRANSFORMER and high AT&C losses. This has been found in District after District across the length and breadth of the country. And highAT&C losses are causing huge Financial Losses to the Discoms.

Total monetary loss of the Discoms in the last few years is about Rs. 4,00,000 Crores. It is therefore important to control Transformer failures and thereby reduce AT&C losses. All of us who are a part of the System, whether Manufacturers of, Utilities, Discoms, Testing Houses, Regulatory Agencies etc. should ponder this point, and take urgent action to stop the massive destruction of National wealth.