Many of our customers - transformer retrofillers and transformer service companies, as well as utilities, generators and industrial clients - all want to know if they should be considering ester fluids when they have a transformer that is going to be retrofilled.
It’s a big conversation - there are always different reasons for the retrofill, each transformer is unique and each company has their own decision making process.
Additionally, there are so many advantages to ester fluids to take into consideration, and there is the question of whether synthetic ester or natural ester is the right product for the retrofill in question.
In an attempt to give companies a simpler starting point for their decision making, we reviewed the many materials, resources and experience we have in transformer fluids and put together a list of the top 4 reasons to retrofill a transformer with an ester fluid instead of mineral oil.
Over 1,000,000 installations worldwide with MIDEL esters. Not one single reported ester fire.
High Fire Point > 300°C (K Class fluid)
Synthetic ester will self-extinguish when heat source is removed.
No pool fires
Readily biodegradability (CIGRE Brochure 436)
Lower clean-up costs compared to mineral oil
Lower environmental impact
Can allow transformers to be located closer together and next to buildings without the need for blast walls.
Compliance with AS2067 can be met and insurance premiums can potentially be lowered.
MIDEL esters are FM Global approved
MIDEL synthetic and natural esters absorb moisture from the insulating paper. This slows the rate of degradation, hence increasing the transformer life.
They allow transformers to run hotter without any reduction in transformer life. Alternatively they can be run at the same temperature as mineral oil with increased paper life.
MIDEL 7131 synthetic ester is oxygen stable which makes it suitable for free breathing transformers.
If you have more questions on the suitability of a natural ester of synthetic ester fluid for a transformer retrofill, don’t hesitate to get in touch with our Customer Service team. We’ll help work through the problem so you are better informed and can make the best decision for the future of your business.