Transformer Maintenance Service

Transformer Installation, Assembly & Testing

Transformers are the critical energy bridge that ensures the power you need keeps flowing to energize our work and lives. Transformers are the most important component in the electrical grid. They transform voltage by stepping it up or stepping it down through magnetic induction within the transformer’s windings. They provide the essential link between two circuits or systems operating at different voltages.

The way a transformer is handled and the procedures that are used to receive, assemble, process and test the transformer are of fundamental importance to the long life of the transformer. The installation and testing of the transformer verify its condition at the time it is ready for service, as well as forming the baseline or signature tests for all future maintenance and later condition assessment or analysis.

Our services include:

  • RECEIVING a transformer after transport to a substation site.
  • ASSEMBLY and PROCESSING of a transformer at the site.
  • TESTING a transformer to verify its suitability for service.
  • INTEGRATING the transformer into the power system.

Preventative maintenance of transformers and upkeep are significant to the reliability and safety of your business and facility. When you’re searching for transformer maintenance companies, it’s important that you choose a partner you can rely on when you need it most. Trust RESA Power to be your one-stop shop for onsite transformer repair and maintenance.

Transformers Services

Liquid-filled transformers are more often found in the electrical circuit than dry-type transformers. These transformers are normally more efficient, have a better overload capability, and usually have a longer life expectancy. Liquid-filled transformers are filled with insulating fluid that performs dual roles: cooling and arc quenching.

A liquid-filled transformer has many parts and pieces. From the bushings (which insulate the energized conductor and have gaskets to keep the fluid in) to radiators, to all the accessories on a transformer, gaskets are a key part of maintenance.

Services include:

  • Assembling all of the parts on a new transformer.
  • Replacing all the old gaskets on a transformer that may be leaking.
  • Replacing parts, painting, and regasketing.
  • Disassemble and move to a new location.
  • LTC (Load Tap Changer) services.

As a transformer ages or as the load increases, the insulating fluid is exposed to high temperatures, often causing sparking, arcing, or even moisture which degrades the fluid’s ability to protect the transformer. Periodic fluid samples are used to determine the quality of the insulating fluid. The fluid analysis also gives us clues as to the health of the transformer, exposes faulty combustible gasses, and identifies potential winding or component failures.

Our oil testing and oil analysis can be done on your site or at our lab in Sacramento, California to conduct proper transformer oil maintenance.

Convenient Transformer Service Locations Nationwide

RESA Power has one of the largest and most comprehensive fleets of transformer-insulating fluid processing components in the country. RESA Power is headquartered in Houston, TX with capabilities across the entire country. Our two transformer services locations in Visalia, CA (Transformer Services West) and Canton, OH & Wilson, NC/Raleigh-Durham (Transformer Services East) are both well equipped to handle all sizes of oil-filled transformers, from large substation power transformers to smaller distribution pad-mounted transformers. Our variety of transformer maintenance service offerings can be combined to exponentially increase the life expectancy of your liquid-filled transformers. Contact RESA Power today for all your transformer repair and maintenance needs.

Electrical Transformer Maintenance Services

Transformers age over time. The biggest factor in the life of a transformer is the quality of the paper that insulates the windings. If not properly maintained, this will lead to failure.

Failure of a transformer can be catastrophic and take literally months to replace (with that portion of the plant it was feeding without power). In order to manage this, we recommend annual fluid analysis and periodic electrical testing of the transformer.

Electrical testing is a series of tests that are performed on the bushings and on the windings of a transformer. Common applications for this service include:

  • When a new transformer is delivered (make sure it is ok).
  • Annual to track the condition.
  • When there are suspected internal problems (from DGA).
  • After major service.

Preventive maintenance of transformers can be the difference between a failed and a successful business. By prioritizing transformer testing and maintenance, you’re making an investment that can save you a massive headache down the line. RESA Power can help you implement an electrical transformer maintenance plan to ensure that your facility avoids unplanned downtime, so your operations can continue running smoothly. Get a quote for RESA Power’s transformer maintenance service today.

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Transformer Installation

At our service centers and repair facilities, We specialize in on-site installations and field assembly, during which our field technicians are able to install either pad mount or substation power transformers, depending on the needs of your facility. Our NETA-certified technicians will safely install the transformer following all ANSI/IEEE and NEMA-approved guidelines and regulations.

Transformer Inspection

The primary purpose of preventative maintenance of transformers and inspection is to ensure the life expectancy of your assets. The external and internal parts of the transformer must be robust and exhibit proper functionality in order to operate safely and efficiently. At RESA Power, we not only perform the maintenance but help you track and keep a historical record of the condition of every transformer through the RESA Transformer Assessment Portal (RESA TAP)!

Transformer Dehydration and Reclamation

Transformer Dehydration and Reclamation are supported with the required oil heating system, regardless of the challenge. RESA Power treatment units generate more heat than most contractors’ equipment, which enables the most effective internal cleansing of sludge and retained moisture in the same number of circulation passes.

Transformer Fluid Maintenance

Each liquid-filled transformer will need to be sampled. To accomplish this, a technician Inspects the transformer looking for problems such as leaks. The tech records the gauge readings (liquid level, temperature, pressure on the tank, nameplate data) and then carefully draws a sample from the transformer. It is pulled by a very careful procedure and packaged to be sent into the lab.

If the results of the test show a problem, the frequency of testing may change. This service can be provided from many of the RESA Power locations and is universally accepted as a required key step in maintaining your transformers.

Transformer oil maintenance services would include:

  • Dehydration and filtration of smaller indoor transformers
  • Mineral Oil Services including:
    • Dehydration
    • Degas
    • Vacuum fill for transformers 69kV or larger
    • Reclaim (using earth)

The transformer oil lab receives the samples and analysis in a couple of key ways. They typically perform a standard screen test which includes:

  • Testing for ppm of dissolved moisture.
  • Testing the dielectric or insulating strength.
  • Testing for the level of acidity.
  • Looking at the color.
  • Testing the Interfacial tension of the oil to detect contaminants.
  • Testing the power factor to identify contaminants.
  • Testing the level of oxidation inhibitor.

There is also the key test of Dissolved Gas Analysis (DGA). This test determines the level and ratio of gasses that the transformer is generating and can determine how the transformer is operating. The DGA will detect any significant problem(s) that a transformer or other liquid-filled apparatus may have.

Routine and Specialized Testing

The maintenance records in the Transformer Assessment Portal (TAP) allow for consistent monitoring of your electrical assets in one convenient location that is available on-demand 24 hours a day, 7 days a week. By accessing TAP you can track your assets, monitor trends, and plan for maintenance of transformer and circuit breaker. RESA Power’s certified technicians and engineers will be available to assist you in the interpretation of the data, monitoring of the equipment, electrical transformer maintenance planning, and execution of transformer testing and maintenance. Scheduling benchmark acceptance tests as well as periodic transformer oil maintenance tests, at regular intervals, will ensure transformer stability and reduce unplanned outages. All tests conducted by RESA Power follow ANSI/IEEE- and NEMA-approved standards.

Click here to log into your account to access RESA Power resources today. Don’t have an account? Click here to register today.

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Transformers are everywhere and every transformer needs some form of service. RESA Power provides full transformer and long-term care (LTC) services, including fluid, mechanical, and electrical repairs and maintenance. We do installation and assembly, complete field regasketing, and full fluid services including dehydration, reinhibit, reclaim and degas processing, including:

  • Minor and Major Repairs
  • Assembly
  • Vacuum Fill
  • Oil Processing Sample Analysis
  • Electrical Testing
  • LTC Services

Our transformer technicians are excellent at pulling samples and inspecting the transformer for required services. We may recommend the best programs that fit the needs of our customers and have transformer experts across the country and an engineering group to solve simple and complex problems.

Avoid Equipment Downtime with RESA Power

RESA Power establishes a comprehensive repair and maintenance schedule to prevent unplanned or service interruptions and immediate major equipment overhauls. In the event that repairs must be made to transformers, switchgear, regulators, reclosers, or controls, our field experts analyze your transformer and identify any required electrical or mechanical repairs. Whether a structural leak, a malfunctioning component, or an electrical test failure, the team at RESA Power has what it takes to make it right.

Quality Replacement Transformer Parts

Need to find a replacement part for that aging electrical asset or equipment? RESA Power offers refurbished components and accessories for vintage transformers and systems. Our transformer repair and maintenance professionals are able to find a number of different types of like-new quality replacement parts: bushings and gaskets; controls and gauges; radiators and valves; and fit and finish supplies. RESA Power supplies many components for late-model equipment as well as discontinued or obsolete systems from all major manufacturers to eliminate equipment downtime at your facility.

Redesigned Like New

When it’s time for a transformer upgrade – RESA Power’s knowledge base of engineers and transformer maintenance service professionals will identify power equipment solutions to fit your budget and maximize your spending dollars. We’ll analyze your needs and specify recommended equipment additions or retrofits that will increase efficiencies and provide a positive impact on your bottom line! Upgrade examples include: tank repairs and modifications; cooling system repairs and improvements, insulating fluid reclamations or retro-fills, fusing additions and upgrades; smart controls and gauge retrofits or repairs (including remote installations); and coil repairs and rewinds, up to 35 kV / 10 MVA.

Learn More about Transformer Retrofill Services

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The Power of Us

Reliable and Safe. It’s not just a catchphrase. It’s how we do business, how we go about our daily activities, and how we work together. Similar to an electrical system, RESA Power is a marriage of many components working together, including employees, equipment, methods, materials, and our environment. RESA Power strives to ensure all of our components, whether mechanical, electrical, or human are quality, fit for use, and always improving. Together we will work toward our mutual benefit (customer and supplier), ensuring the longevity of our clients’ assets and electrical equipment. Whether a simple power transformer repair service such as descaling mineral deposits from transformer cooling panels for improved cooling efficiency or the intricacies of overhauling a power transformer’s on-load tap changer, contact RESA Power, your local expert. The Power of Us.


RESA Power has more than 40 service locations across the United States and Canada, including a transformer oil testing laboratory and specialty distribution centers to ensure our customers’ critical power systems are safe, reliable, and operating at peak efficiency. Click on the service center nearest to you for more information.