Power Transformers

Retrofitting on transformers with capacity up to 100 MVA and, 230 kV voltage class

Services in the field such as liquid treatment, , replacement of accessories, commissioning and start-up, etc.

Rental of transformers.

Distribution, Vault and Padmount Transformers

We make reforms and retrofitting in transformers of distribution, medium power, corrugated, pedestal, with capacity up to 10 MVA, class of tension up to 35 kV, with services of redesign and repotencialização; We perform maintenance services in the field such as mineral oil treatment, vegetable oil, emergency service, replacement of accessories, etc. Commissioning and Start-up of equipment for entry into operation; Distribution transformer rental, medium power, corrugated, pedestal, in the classes 15kV, 25kV, 35kV in the power up to 10 MVA.

Epoxy encapsulated dry distribution transformers

We specialize in retrofitting and retrofitting in epoxy encapsulated dry distribution transformers with capacity up to 10 MVA, Voltage class up to 35 kV. We carry out maintenance services in the field, emergency service, replacement of accessories, etc. Commissioning and Start-up of equipment for entry into operation; Rental of dry transformers encapsulated in epoxy, in the classes 15kV, 25kV, 35 kV in the power up to 10 MVA.


We apply methods of performing the services with standard routines, according to ABNT technical standards, for each manufacturer. The team is coordinated by supervisors with sufficient qualification and support for all necessary tests, as well as interpretation of the results obtained and indication of the solutions and measures to be taken.

Corrective Maintenance

Execution of repairs and / or replacement of equipment in high and medium voltage detected in the predictive interventions or in emergency situations. Replacement of switchgear, replacement of TPs and protection CTs, repair and / or replacement of high and medium voltage equipment (transformers, circuit breakers, regulators, reclosers, lightning arresters).

Predictive Maintenance

Collection of monitored data and field inspection. We also offer more specific services for more accurate diagnosis, such as Physical Chemical Analysis and Chromatographic Gas in vegetable oil and mineral insulation.

Predictive Maintenance

Preventive Maintenance is done in:

- Distribution transformers,

- Power transformers,

- Circuit breakers and disconnecting switches,

- Rotating panels and cubicles,

- Protection relays.

Eletrical Maintenance

We are specialized in predictive, preventive and corrective maintenance services in high and medium voltage substations and distribution networks. Our team operates from diagnosis to fault rectification.

Project and construction

Medium Voltage Substations and Transformation Stations

COMTRAFO Services ensures agility in carrying out projects and in the construction of medium voltage substations, cubicles and transformation stations. Our specialized team is in all stages, from the elaboration of the technical project and commercial evaluation to the delivery of the enterprise, anywhere in Brazil.

Substation in high voltage

COMTRAFO Serviços applies its know-how in the development of customized solutions in high voltage (15kV to 36kV).

- Technical and financial feasibility studies;

- Elaboration of civil, electrical and electromechanical projects;

- Short-circuit studies and selectivity coordination;

- Civil works, electromechanical assembly and commissioning;

- Final tests, energizing technical and operational training;

- Data Book (supplies of all related documentation).

Renovation of Cabins and Substations

COMTRAFO Services performs retrofit or retrofit of substations with elaboration of revitalization projects and expansion of facilities, with the objective of gaining efficiency and guaranteeing the maintenance of the useful life of the electric assets.


Lines of action:

- Expansion and revitalization projects;

- Electromechanical assembly and installation;

- Reform of panels and equipment;

- Electromechanical tests;

- Automation projects;

- SPDA projects;

- Commissioning and stat-up.


Reform and relocation of circuit breakers.



Breaker location and retrofit


COMTRAFO Services has a logistics company from the COMTRAFO Group, ARIM, which serves the entire national territory.

The Comtrafo also works with companies in international logistics ensuring delivery around the globe.


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