Reinhibiting Oil-Filled Transformers

Maintaining Optimal Performance and Longevity

At RESA Power, we understand the importance of maintaining optimal performance and longevity when it comes to oil-filled transformers. That’s why we offer a comprehensive range of transformer services, including transformer reinhibiting. Our experienced team of technicians is equipped with the knowledge and expertise necessary to provide effective solutions for transformer inhibitor maintenance, ensuring you maintain the longevity of your transformers and maximum performance.

Whether you need routine oil-filled transformer maintenance or a transformer reinhibiting service, RESA Power is your go-to source for all your power transformer service needs. Trust in our expertise and experience to keep your transformers running smoothly for years to come.

Get a Quote for Reinhibiting Oil-Filled Transformers


Get a Quote for Reinhibiting Oil-Filled Transformers

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Benefits of Using Oxidation Inhibitors in Power Transformers 

Oxidation inhibitors play a crucial role in power transformers by preventing the oxidation of the transformer oil and the formation of harmful byproducts that can hinder performance or lead to even more significant problems. These oxidation inhibitors therefore can help to extend the lifespan of the transformer and improve its overall performance.

Inhibiting the Formation of Sludge and Deposits

The benefits of using oxidation inhibitors in power transformers include increased operational reliability, reduced maintenance costs, and improved energy efficiency. One of the key advantages of using oxidation inhibitors is their ability to inhibit the formation of sludge and deposits in the transformer insulating oil.

Sludge and deposits can lead to insulation breakdown, reduced heat transfer efficiency, and increased risk of equipment failure. By preventing the oxidation process, the inhibitors help to maintain the oil’s stability and cleanliness, ensuring optimal performance of the transformer.

Minimize the Degradation of Insulation

Furthermore, oxidation inhibitors also help to minimize the degradation of cellulose insulation in power transformers. Cellulose insulation is commonly used in oil-filled transformers to provide electrical insulation. However, over time, oxidation can cause the cellulose to deteriorate, leading to reduced insulation properties and an increased risk of electrical faults and potentially an outage and downtime.

By inhibiting oxidation, these inhibitors help to preserve the integrity of the cellulose insulation, thereby extending the lifespan of the power transformer.

Improve Energy Efficiency in Power Transformers

In addition to these benefits, oxidation inhibitors also contribute to improved energy efficiency in power transformers. Oxidation reactions generate heat, which can lead to increased operating temperatures in the transformer.

By preventing oxidation, the inhibitors help to reduce heat generation and maintain lower operating temperatures. This not only improves the energy efficiency of the power transformer but also reduces the need for cooling systems, resulting in cost savings.

Overall, the use of oxidation inhibitors in power transformers offers numerous benefits, including increased operational reliability, reduced maintenance costs, improved energy efficiency, and extended lifespan. These oxidation inhibitors play a vital role in ensuring the optimal performance and longevity of power transformers.

Maximizing Transformer Lifespan through Reinhibiting and Proper Inhibitor Maintenance

The lifespan of a power transformer is heavily dependent on how well it’s taken care of. By prioritizing the reinhibiting process for oil-filled transformers and maintaining proper inhibitor levels, you can significantly increase their lifespan. In analyzing extensive data, it’s clear that those who diligently monitor their power transformers and invest in regular reinhibiting services extract far more operational hours from their transformers compared to those who don’t.

The benefits of this are two-fold: not only do you reduce the need for costly replacements, but you also optimize the efficiency and cost-effectiveness of your transformer assets by reducing chances for downtime. Therefore, proper routine transformer inhibitor maintenance is crucial to ensuring optimal transformer performance and maximizing its longevity.


It is important to assess the type of insulating oil in a unit before determining if an oxidation inhibitor is necessary.

RESA Power Recommends

In the case of type I oil (uninhibited), we won’t always recommend the use of an inhibitor. Instead, we will carefully evaluate the oxygen levels present. This approach ensures that we provide tailored and appropriate solutions for each specific case, optimizing the performance and longevity of the unit. By considering the unique characteristics and requirements of each transformer, RESA Power delivers targeted recommendations that align with the highest standards of quality and effectiveness.

Protect Your Transformers with Oil Inhibitor Services

Managing and maintaining transformers is crucial to ensuring their longevity and productivity. One of the most significant threats to your transformers is sludge build-up caused by oxidation in the insulating fluid. Fortunately, RESA Power’s Oil Inhibitor services offer a solution to this serious problem. Our transformer reinhibiting service utilizes BHT to combat sludge-causing free radicals and protect the molecular structure of the insulating fluid from the harmful effects of oxygen and other contaminants.

Don’t wait until it’s too late to take action. Trust our transformer inhibitor maintenance services to safeguard your vital electrical assets. Let us help you keep your transformers in top condition for years to come.

Understanding Transformer Oxidation Inhibitors

Most mineral oil dielectric fluids contain an added oxidation inhibitor, a chemical additive that acts as a preservative. The primary purpose of the inhibitor is to prevent oxygen from reacting with the oil, thereby slowing down the aging process of the oil and solid insulation. 

Two commonly used oxidation inhibitors in transformer oils are:

  • 2,6-ditertiary-butyl para-cresol (DBPC)
  • 2,6-ditertiary-butyl phenol (DBP), the latter also known as butylated hydroxytoluene (BHT)

Maintaining Optimal Inhibitor Concentration

At RESA Power, we recognize the importance of maintaining an adequate inhibitor concentration in power transformer oil. Through Fourier Transform Infrared (FTIR) spectroscopy, we determine the total concentration of oxidation inhibitors in the transformer oil.


An inhibitor concentration of less than 0.1% (by weight) is considered unacceptable as it provides insufficient protection against oxidation.

RESA Power Recommends

Should the inhibitor level drop below 0.1%, we recommend re-inhibiting the oil and adding inhibitors to bring the concentration back up to 0.3%.

Our Transformer Reinhibiting Process

Reinhibiting is a critical step in ensuring the continued protection of your oil-filled transformers. Our team of experienced technicians specializes in the reinhibiting process, combining technical expertise with state-of-the-art equipment.

Following the purification process (dictated by oil sample results), our technicians add a concentrated solution of 2,6-di-tert-butyl-p-cresol (DBPC) inhibitor to the oil stream returning to the transformer, utilizing our formula to add the correct amount required.


The final concentration of inhibitor in the oil should be 0.3% (by weight). This complies with standards IEC 60296, ASTM D3487, AS1767.

RESA Power Recommends

If the acid number of the oil exceeds 0.06 mg KOH/g or the interfacial tension (IFT) drops below 31.9 mN/m, additional oil reclamation and reinhibiting may be necessary.

Choose RESA Power for Reinhibiting Oil-Filled Transformers 

Maintaining the optimal functionality and reliability of your oil-filled transformers is crucial to ensure continuous optimal performance. This is where RESA Power comes in as a dependable and experienced partner for transformer reinhibiting service. When it comes to reinhibiting transformers, our team of experts utilizes state-of-the-art equipment and techniques to provide transformer inhibitor maintenance tailored to your specific needs.

By choosing RESA power for your transformer maintenance service, you can enhance the efficiency and extend the lifespan of your transformers. Get in touch with us today to learn more about our reinhibiting transformers services and how we can help you optimize your electrical power equipment’s performance.

Get a Quote for Reinhibiting Oil-Filled Transformers

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