A furan test is a type of dissolved gas analysis (DGA) test that is used to measure the levels of furan compounds in transformer oil. Furan compounds are produced by the breakdown of cellulose, which is the main component of transformer insulation. High levels of furan compounds in transformer oil can indicate that the insulation is degrading and that the transformer is at risk of failure.
Why is a furan test important?
Furan tests are important because they can help to detect problems with the transformer’s insulation early on, before they cause transformer failure. Transformer failure can be a costly and disruptive event, so it is important to identify potential problems as soon as possible.
What are the limits for furan test results?
The limits for furan test results will vary depending on the type of transformer, the operating conditions, and the age of the transformer. However, in general, the following limits are used:
- Furfural: 2.0 ppm (typical limit) or 5.0 ppm (high limit)
- 5-Methylfurfural: 1.0 ppm (typical limit) or 3.0 ppm (high limit)
- 2-Furylfuran: 0.5 ppm (typical limit) or 1.5 ppm (high limit)
What to do if furan test results exceed the limits?
If the furan test results exceed the limits, then it is important to investigate the cause of the problem and take corrective action to prevent transformer failure. This may involve:
- Increasing the frequency of transformer oil testing
- Performing additional diagnostic tests
- Taking steps to repair or replace the transformer insulation
How to prevent high furan levels in transformer oil
There are a number of things that can be done to prevent high furan levels in transformer oil, including:
- Avoiding overloading the transformer
- Operating the transformer at low temperatures
- Using high-quality transformer oil
- Keeping the transformer oil clean and free of contaminants
- Regularly testing the transformer oil for moisture and other impurities
By following these tips, you can help to extend the lifespan of your transformer and reduce the risk of transformer failure.