On Load Tap Changer Service

On Load Tap Changer Service


An On Load Tap Changer (OLTC) failure can be catastrophic to the rest of the system. Documented surveys have proved that about 40% of the OLTC- equipped transformer failures are caused by the failure of the OLTC. The moving parts of an OLTC are far more prone to routine wear and tear than the fixed components. When an OLTC fails, it takes the transformer with it. Protecting this vulnerable component of your transformer with regular inspection and testing is non-negligible.

So with regular oil testing and overhauling, you'll know when it is time to replace wear parts & schedule the maintenance before they become a major threat to the operations of your plant.

What Does An OLTC Inspection Reveal? :

Mechanical faults,
  • such as worn springs and bearings, can cause substandard operation of the OLTC, shortening the life of the equipment as it experiences prolonged pitting & arcing under heavy loads. At such occasions, contacts can fall at the tank bottom or even loosen.
Electrical faults,
  • such as excessively worn or heavily tattered contacts, can lead to burned or welded components and potential failure of the unit.
Insulation oil deterioration,
  • Can seriously hinder the insulating effect of the oil and lead to overheating.
Faulty gaskets,
  • Can cause contamination of OLTC and transformer oil. This condition can sometimes be seen in ratios of combustible gases.
Asian Electrotech Industries LLP

Since 1996, Asian Electrotech Industries LLP has been serving the Indian Power Sector. With more than 25 years in the industry, AEIL has the technical expertise in erection, testing, commissioning & maintenance of electrical substation up to 66KV.

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