Why are transformer oil trays so important?

For legally compliant and correct storage of hazardous substances, oil collection trays for transformers are a necessary and effective solution. They capture leaking insulating oils directly and thus protect both water resources and the environment. Transformer oil trays are made of plastic or steel, they are available for various transformer sizes and should be inspected regularly. Read more here.

How is transformer oil classified by law?

The Water Resources Act (WHG) in Germany, for example, classifies solid, liquid and gaseous substances as hazardous if they cause permanent or significant damage to the quality of the water.

Oil or used oil is categorised as a particularly severe threat to the environment and to water bodies (WGK = water hazard class 3). Just a few drops of oil pollute many times the amount of water.

Transformer oil - how dangerous is it?

Until today, mainly mineral oil-based transformer oils have been used. They are used for insulation and cooling as well as for heat exchange. Since some components of these insulating oils are harmful to the environment, professional handling with suitable equipment is necessary. This depends on the environmental conditions.

Transformers, which have been filled with mineral oil-based insulating oils before 1989 may contain polychlorinated biphenyls (PCBs). These can be toxic to humans and the environment and are not biodegradable.

The containment of transformers is important to prevent contamination of the environment by the insulating oil. Likewise, safe disposal must be ensured. The hydrocarbons in transformer mineral oils can cause fires if they evaporate or overheat.

Therefore, a containment in the form of a transformer oil tray is necessary to prevent environmental damage.

What are the regulations for transformer oil trays?

Legislation stipulates the storage of hazardous substances in several laws or directives and ordinances. These deal with both the general handling of substances hazardous to water and precise drip tray regulations and are interrelated. 

Trays for transformer oils can be made for example of galvanised or painted steel, or optionally of stainless steel or polyethylene (LLDPE).

It is advisable to have a visual inspection carried out every two years, and a detailed inspection of the oil tray carried out by a specialist company every five years together with the insulating oil analysis. 

Transformer oil trays are usually inspected together with other maintenance work

Long before major damage is apparent in transformers, transformer oil analyses provide important indications of possible weaknesses. That is why the insulating oil in transformers is to be regularly checked. This is a good opportunity to also take a look at the transformer oil trays.

Identify leaks at an early stage and prevent seepage with oil trays

Transformer oil collection trays prevent leaking oil from seeping into the ground and thus protect the environment and water bodies. At the same time, the tray serves as an early warning system for the condition of the transformers. Because even the smallest leaks are quickly visible through the formation of shimmering oil puddles in the collection tray.

Regularly checking the transformer oil trays for leaks is important.  It is best to have this always carried out together with the scheduled insulating oil analysis. A simple visual inspection at shorter intervals is also useful.

Specialist companies regularly inspect oil trays

For specialist companies, the inspection of oil spill trays is a matter of course. As an experienced specialist company and Europe-wide expert in recycled and new insulating oils as well as comprehensive transformer services, Electrical Oil Services (EOS®) offers comprehensive, reliable maintenance and services.

Find out more in these blog articles:

• Transformer maintenance: when should you replace the insulating oil in transformers? 
• Valuable tips if you want to have the insulating oil in the transformer changed 
• Laboratory services for insulating oils: This is what you need to look out for
  
  
  

Stay informed with our EOS Trusted Purity Blog!

Conclusion

When operating transformers and handling insulating oil, oil trays and their regular inspection are mandatory. Make sure that your specialist company, which examines the condition of your transformers, also includes restraint systems such as oil trays in the maintenance work. This also includes checking whether the oil trays are integrated into the earthing system. As a specialised company according to the Water Resources Act (WHG), this work is a matter of course at Electrical Oil Services .

We at EOS work exclusively with trained specialist personnel, strictly adhere to standards and regulations and carry out all work processes professionally and carefully.

Do you have any questions? We will be happy to advise you personally. Contact us directly: