How is transformer oil filtered?

How is transformer oil filtered?

The process filters fine contaminated particles with the help of a filtering device. The Purification with Drying Process heats the oil to a maximum temperature of 90 degree Celsius and removes acidic & polar components from the transformer oil. A process of degassing under vacuum follows.

What is the frequency of BDV testing of transformer?

Routine testing of transformer oil should be done every 2 years on a regular schedule.

How do you purify a transformer oil?

First step is to raise oil temperature up to 65°C to give latent heat which separates moisture and gases. Heating the oil will make it easier to filter because of the decrease in oil viscosity. Second step is to remove sludge and dirt from the insulating oil.

How often do transformers need to be replaced?

TEPCO decommissioned 20 transformers with a service life of between 30 years and 50 years to evaluate the level of deterioration as a result of aging. Transformers are designed with an expected life span of 30 years, though some in Japan have been in service for more than for 50 years.

What is transformer maintenance schedule?

Transformer Maintenance on a Half Yearly Basis Your electrical transformer needs to be checked every 6 months for IFT, DDA, flash point, sludge content, acidity, water content and dielectric strength along with how resistant it is to transformer oil.

How do you maintain a transformer?

Annual Transformer Maintenance Schedule

1. Make sure that you clean all the bushings of your electrical transformer with only soft cotton cloth annually.
2. Oil condition of OLTC should be carefully examined on an annual basis.
3. Make sure to clean out the inside of all of the marshalling boxes annually.

How do you test a BDV?

For measuring BDV of transformer oil, portable BDV measuring kit is generally available at site. In this kit, oil is kept in a pot in which one pair of electrodes are fixed with a gap of 2.5 mm (in some kit it 4 mm) between them. Now slowly rising voltage is applied between the electrodes.

Is BDV of transformer oil used in 11kv substation?

As per IEC, the minimum breakdown voltage of transformer oil should be not less than 30 KV. The BDV of transformer oil does not depend on the voltage rating of the transformer. Minimum transformer BDV value for either 11 KV, 22 KV, 132 KV is the same. The minimum transformer oil BDV is 30 KV.

How long can a transformer last?

In the U.S. alone, analysts say the average age of a transformer on the grid is 35 years old, near the end of its typical lifecycle. Under ideal conditions, transformers are expected to operate for 30 to 40 years, while industrial transformers have a life expectancy of just 20 to 25 years.