top of page

Transformers...more than meets the eye!

When we think of large electrical transformers at Utilities, we don't typically view them as ticking time bombs...but without preventative maintenance that's exactly what they are!

The purpose of a transformer is to drop the voltage coming from power lines. These transformers can be huge; the size of a car or greater. Sealed inside of the transformers is an oil bath surrounding all of the electrical coils. This oil bath acts as both a coolant and an insulator. At the top of the transformer, there is a headspace that has no oil and instead is filled with an inert gas such as Nitrogen...generally under a slight positive pressure to prevent air/moisture ingress.

For a new transformer, this nitrogen blanket will remain “clean” for a long time. As the transformer ages, and the insulation between the wire coils start to break down, the high voltage can arc between two adjacent coils of the transformer. When this occurs, the high voltage passing through the oil blanket causes the oil to break down. This causes small amounts of flammable vapors to form from the oil, and rise to the top of the transformer to mix with the nitrogen blanket. These flammable vapors consist of a variety of gases, but generally hydrogen is predominant.


Periodic testing of the nitrogen blanket for flammable vapors is a good indication of the health of the transformer. If the testing reveals a buildup of flammable vapors, the transformer can be removed from service in a planned manner instead of a catastrophic manner (they can blow up if undetected).

Substation Transformer Fire

KCPL Hawthorn (Pictured Above) 08/11/2016

"So What Should I Do!?!?" - YOU

FIRST....Take a moment NOW to watch this 3-Minute Video below and DISCOVER how EASY it is to prevent a transformer explosion from occurring at your plant or on your next project. Economy Power & Instrument, Inc. to schedule your inspection or to secure your own Portable Eagle Gas Detector!

Best Regards,

Brandon Jamison

Special Accounts Manager Economy Power & Instrument, Inc.

10616 Summit

Lenexa, KS 66215

(913) 469-1111

Featured Posts
Recent Posts
Search By Tags
Follow Us
  • Facebook Classic
  • Twitter Classic
  • Google Classic
bottom of page